The document describes the construction of a solenoid electric engine made by students as a class project. It includes 6 steps to construct the engine using 4 AC solenoid coils connected to a DC motor that controls the power supply to the coils. The components used are listed along with details of the solenoid coils and applications of electromechanical solenoids.
The document discusses DC motors and their construction and operation. It provides three key points:
1) It describes the basic construction of a DC motor, including its stator, rotor, commutator, and brushes. The stator contains poles that generate a magnetic field, while the rotor contains coils connected by the commutator.
2) It explains how a DC motor operates, with the interaction between the magnetic field and current in the rotor coils generating a torque that causes rotation. The commutator switches the current direction to maintain rotation.
3) It presents the equivalent circuit of a DC motor/generator, modeling the magnetic flux generated by the field coils, the back EMF induced in
A practical guide to free energy devices pages 23 32 - patrick j. kellyMrinal Pal
This document discusses permanent magnet motors and generators. It begins by explaining how permanent magnets work and debunking the idea that they cannot do work. It then summarizes several designs for permanent magnet motors and generators, including ones that use rotating magnetic shields to produce power without resistance. Key designs discussed include those by John Bedini, Wang Shum Ho, John Ecklin, and Howard Johnson. The document emphasizes that permanent magnets can power generators indefinitely without external fuel.
An AC generator converts mechanical energy to electrical energy using Faraday's law of electromagnetic induction. It contains a coil called an armature that rotates inside a magnetic field produced by magnets. As the armature spins, the changing magnetic flux induces an alternating current (AC) in the coils. Slip rings and carbon brushes allow the current to be conducted from the moving armature to an external circuit. The amount and direction of the induced current depends on the speed of rotation and position of the armature plane relative to the magnetic field.
The document discusses DC motors, DC generators, AC motors, and AC generators.
1. A DC motor converts direct current into mechanical energy using the Lorentz force principle. It has an armature and stator. A DC generator converts mechanical energy into direct current using electromagnetic induction.
2. The key differences between AC and DC machines are that AC motors have rotating magnetic fields and multiple phases while DC motors have a rotating armature. AC generators have fixed coils and rotating magnets, making construction simpler, while DC generators have commutators.
3. The document provides definitions, construction details, working principles, and comparison of the different motor and generator types.
This document provides information about understanding AC/DC motors and generators theory. It outlines the objectives, safety requirements, risk level, and evaluation criteria for a block of instruction. The instruction will cover fundamentals of rotating machines, different types of DC motors and generators, induction motors, and motor theory concepts. Students will be evaluated on an examination and must score 80% or higher to pass. Lab exercises will use Labvolt trainers to cover the topics.
The document provides information on solenoids, including:
1. Solenoids produce a magnetic field when electric current flows through a coil wound around an iron core.
2. They are used to convert electrical energy to mechanical energy and can be used to engage or disengage components.
3. Common applications of solenoids include starters in vehicles, locks, and devices that control engine functions.
This document provides information about basic AC electrical generators. It discusses different types of generators including rotating armature generators, rotating field generators, and polyphase generators. It also covers topics like air cooled generators, temperature rise, reliability, construction details, stator and rotor design for both air cooled and hydrogen/water cooled generators. The document includes sections on generator isolation, seal oil systems, stator cooling water systems, and excitation systems. It concludes with sample review questions and a final examination.
DC generators convert mechanical energy into direct current electricity through the principle of dynamically induced electromotive force (emf). They have a rotor with coils that spin inside a stationary magnetic field produced by poles. Commutation is needed to change the alternating current induced in the coils to direct current, which involves using brushes and commutator segments. Methods to improve commutation include using resistance or interpoles to neutralize reactance voltage. DC generators are now less common but still used to provide excitation to alternators or in locomotives for regenerative braking. DC motors are used where variable speed or high starting torque is required, such as in cranes, compressors or tractions systems.
The document discusses DC motors and their construction and operation. It provides three key points:
1) It describes the basic construction of a DC motor, including its stator, rotor, commutator, and brushes. The stator contains poles that generate a magnetic field, while the rotor contains coils connected by the commutator.
2) It explains how a DC motor operates, with the interaction between the magnetic field and current in the rotor coils generating a torque that causes rotation. The commutator switches the current direction to maintain rotation.
3) It presents the equivalent circuit of a DC motor/generator, modeling the magnetic flux generated by the field coils, the back EMF induced in
A practical guide to free energy devices pages 23 32 - patrick j. kellyMrinal Pal
This document discusses permanent magnet motors and generators. It begins by explaining how permanent magnets work and debunking the idea that they cannot do work. It then summarizes several designs for permanent magnet motors and generators, including ones that use rotating magnetic shields to produce power without resistance. Key designs discussed include those by John Bedini, Wang Shum Ho, John Ecklin, and Howard Johnson. The document emphasizes that permanent magnets can power generators indefinitely without external fuel.
An AC generator converts mechanical energy to electrical energy using Faraday's law of electromagnetic induction. It contains a coil called an armature that rotates inside a magnetic field produced by magnets. As the armature spins, the changing magnetic flux induces an alternating current (AC) in the coils. Slip rings and carbon brushes allow the current to be conducted from the moving armature to an external circuit. The amount and direction of the induced current depends on the speed of rotation and position of the armature plane relative to the magnetic field.
The document discusses DC motors, DC generators, AC motors, and AC generators.
1. A DC motor converts direct current into mechanical energy using the Lorentz force principle. It has an armature and stator. A DC generator converts mechanical energy into direct current using electromagnetic induction.
2. The key differences between AC and DC machines are that AC motors have rotating magnetic fields and multiple phases while DC motors have a rotating armature. AC generators have fixed coils and rotating magnets, making construction simpler, while DC generators have commutators.
3. The document provides definitions, construction details, working principles, and comparison of the different motor and generator types.
This document provides information about understanding AC/DC motors and generators theory. It outlines the objectives, safety requirements, risk level, and evaluation criteria for a block of instruction. The instruction will cover fundamentals of rotating machines, different types of DC motors and generators, induction motors, and motor theory concepts. Students will be evaluated on an examination and must score 80% or higher to pass. Lab exercises will use Labvolt trainers to cover the topics.
The document provides information on solenoids, including:
1. Solenoids produce a magnetic field when electric current flows through a coil wound around an iron core.
2. They are used to convert electrical energy to mechanical energy and can be used to engage or disengage components.
3. Common applications of solenoids include starters in vehicles, locks, and devices that control engine functions.
This document provides information about basic AC electrical generators. It discusses different types of generators including rotating armature generators, rotating field generators, and polyphase generators. It also covers topics like air cooled generators, temperature rise, reliability, construction details, stator and rotor design for both air cooled and hydrogen/water cooled generators. The document includes sections on generator isolation, seal oil systems, stator cooling water systems, and excitation systems. It concludes with sample review questions and a final examination.
DC generators convert mechanical energy into direct current electricity through the principle of dynamically induced electromotive force (emf). They have a rotor with coils that spin inside a stationary magnetic field produced by poles. Commutation is needed to change the alternating current induced in the coils to direct current, which involves using brushes and commutator segments. Methods to improve commutation include using resistance or interpoles to neutralize reactance voltage. DC generators are now less common but still used to provide excitation to alternators or in locomotives for regenerative braking. DC motors are used where variable speed or high starting torque is required, such as in cranes, compressors or tractions systems.
The document describes the design and construction of an electromagnetic actuator that converts electrical energy into linear reciprocating motion. It consists of two magnets - an electromagnet and a permanent magnet. The electromagnet is powered by a battery and its polarity is switched to alternately repel and attract the permanent magnet piston, causing it to move back and forth. This linear motion is then converted into rotational motion using connecting rods and a crankshaft.
A DC generator converts mechanical energy into direct current electrical energy. It consists of a magnetic field and conductors that move within the field. As the conductors cut through the magnetic flux, an electromotive force is induced according to Faraday's law of induction. Early commercial uses of electricity relied on batteries, but generators provided a more efficient means of power generation. Elihu Thomson developed an early DC generator design that maintained a constant voltage, representing an improvement over prior models. DC generators can operate as motors and vice versa, and find applications that require direct current power sources.
A Project made for my School in the 10th Grade explaining the differences and working of AC and DC Generators.
Contents:
-Introduction
-Electromagnetic induction
-EMF- Electromotive Force
-Fleming’s Right Hand Rule
-Components of a Generator
*Rotor
*Armature
*Coil
*Stator
*Field electromagnets
*Brushes
-A.C. generators
-Commercial A.C generators
-DC generators
-Principle
-Working
-Differences between AC and DC
The document discusses synchronous generators and their operation. It covers:
- The two reaction theory which separates the armature mmf into direct and quadrature axis components.
- How phasor diagrams can be used to represent the direct and quadrature axis reactances (Xd and Xq).
- The slip test method to measure Xd and Xq by taking voltage-to-current ratios with the armature mmf aligned to each axis.
- Important cautions for the slip test including keeping slip extremely low to avoid errors from damper windings or open circuit voltages reaching dangerous levels.
This document discusses the key components and operating principles of DC generators. It describes the essential parts of a practical generator including the magnetic frame, pole cores, field coils, armature core, armature windings, commutator, brushes and bearings. It also covers different types of armature windings such as lap and wave windings. Finally, it discusses losses that occur in DC generators and conditions for maximum efficiency.
This document discusses a study on the application of eddy current brakes in automobiles. It begins with an introduction to eddy current brakes, explaining that they slow objects by dissipating kinetic energy as heat using opposing eddy currents induced by a magnetic field. It then covers the principles and types of eddy current brakes, how they work using electromagnetic induction, their advantages like being non-mechanical and fully resettable, and their disadvantages like diminished braking force at low speeds. It concludes by discussing applications of eddy current brakes for additional safety on long mountain descents and for high-speed vehicles.
This document provides an overview of eddy current brakes, including their introduction, types, working principle, advantages, disadvantages, applications, and future aspects. Eddy current brakes use electromagnetic induction to generate closed loops of eddy currents in a conductive material, like a metal disc attached to a vehicle's wheel. This creates counter magnetic fields that oppose the motion of the conductor to generate braking force without contact. The document discusses two main types - linear brakes that induce eddy currents in rails, and circular brakes that use a conductive disc. Applications include trains, roller coasters, and other machinery where contact-based braking could wear out.
The document discusses the key components of AC generators, including the field, armature, prime mover, rotor, and stator. It explains that the field produces a magnetic flux, the armature produces voltage as this flux cuts through it, and the prime mover provides rotational power. There are two main types of AC generators - those with a stationary field and rotating armature, and those with a rotating field and stationary armature. The rotating field, stationary armature type is commonly used for large power generation.
Electric motors and generators both use the principle of electromagnetic induction to convert between electrical and mechanical energy. Electric motors convert electrical energy into mechanical motion by using a rotating electromagnet within a magnetic field, while electric generators convert mechanical energy into electrical current by rotating a coil of wire within a magnetic field. The key components needed for both are an electrical coil, a magnetic field, and a way to transfer the induced current such as slip rings or a commutator.
This document discusses different types of motors, including DC motors, AC motors, and servo motors. It describes the key components and characteristics of series, shunt, and compound DC motors. It also explains induction motors, synchronous motors, and the differences between squirrel cage and wound rotors. AC motors are divided into synchronous and induction types. Servo motors are described as incorporating a DC motor, gear train, potentiometer, and control circuit to enable precise angular positioning. Common applications of different motor types are also mentioned.
Construction and components of DC Machine – Principle of operation – Lap and wave windings-EMF equations– circuit model – armature reaction –methods of excitationcommutation – interpoles compensating winding –characteristics of DC generators.
A solenoid is a coil of wire that produces a magnetic field when electric current passes through it. Inside the solenoid, the magnetic field lines are parallel and uniform. Outside the solenoid, the magnetic field is non-uniform and weak due to cancellation of opposing field lines between coil turns. Solenoids can operate using direct current (DC) or alternating current (AC). DC solenoids consist of a coil, field/helix, and plunger that moves in one direction when energized. Solenoids have many applications including locking mechanisms, automotive systems, medical devices, railways, and industrial machinery.
An AC generator converts mechanical energy to electrical energy by rotating a coil within a magnetic field or rotating the magnetic field around a stationary coil. It produces alternating current unlike a DC generator. The main components of an AC generator are the field, armature, prime mover, rotor, and stator. The rotor is driven by the prime mover and either the rotor or stator contains the field coils. Losses in the AC generator occur due to resistance in the armature windings, hysteresis in the iron cores, and mechanical friction from bearings and windage. The efficiency of an AC generator is the ratio of its output power to input power.
A DC generator converts mechanical energy into electrical energy through electromagnetic induction according to Faraday's Laws. It has two main parts: a magnetic field and conductors. When the conductors move within the magnetic field, a voltage is induced across the conductors and electrical energy is generated.
This document discusses the components and operation of an AC generator. It describes the key parts including the field, armature, prime mover, rotor, stator and slip rings. The field and magnetic flux produce voltage in the armature. The rotor is driven by the prime mover and its rotation through the magnetic field induces current in the armature coils. Slip rings allow current to flow in and out of the rotating component. AC generators have advantages over DC generators for applications such as power generation.
This document provides a summary of a project report on industrial automation in 2015 focusing on AC and DC motors and transformers. It includes sections on acknowledging those who provided guidance, the contents which discuss principles and construction of DC motors, AC motors, and transformers. For DC motors, it explains types including series, shunt, and compound, as well as construction details and speed control methods. For transformers, it discusses working principles, types by construction, voltage transformation ratios, and equivalent circuits. It also provides overviews of induction motors and synchronous motors as types of AC machines.
Eddy current brakes work by generating eddy currents in a conductor when it moves through a changing magnetic field. This induces an opposing magnetic field that creates a braking force based on Lenz's law. There are two main types - circular brakes with a disc between electromagnet poles, and linear brakes using a rail and magnetic yoke. Advantages include no wear, adjustable braking, and being lightweight; disadvantages are reduced braking at low speeds and difficulty designing and simulating the system. Applications include high speed trains and roller coasters.
The document provides information about solenoids and DC motors. It defines a solenoid as a coil that produces a magnetic field when electric current passes through it. Solenoids are used to create controlled magnetic fields and can act as electromagnets. The document also describes various applications of solenoids such as in valves, switches, starters, and linear actuators. It then discusses DC motors and how they work using electromagnetic principles and a commutator to reverse polarity and keep the motor rotating. A fan regulator circuit is also shown that uses a variable resistor to control current and dim a lamp.
Mrs. Dharani Venkatesh provided guidance and support to help the student successfully complete their physics project. The Principal, Vice Principal, and Correspondent also supported the student by giving them the opportunity to do this mini project. Finally, the student's parents and friends helped finalize the project within the limited time frame.
The document describes the design and construction of an electromagnetic actuator that converts electrical energy into linear reciprocating motion. It consists of two magnets - an electromagnet and a permanent magnet. The electromagnet is powered by a battery and its polarity is switched to alternately repel and attract the permanent magnet piston, causing it to move back and forth. This linear motion is then converted into rotational motion using connecting rods and a crankshaft.
A DC generator converts mechanical energy into direct current electrical energy. It consists of a magnetic field and conductors that move within the field. As the conductors cut through the magnetic flux, an electromotive force is induced according to Faraday's law of induction. Early commercial uses of electricity relied on batteries, but generators provided a more efficient means of power generation. Elihu Thomson developed an early DC generator design that maintained a constant voltage, representing an improvement over prior models. DC generators can operate as motors and vice versa, and find applications that require direct current power sources.
A Project made for my School in the 10th Grade explaining the differences and working of AC and DC Generators.
Contents:
-Introduction
-Electromagnetic induction
-EMF- Electromotive Force
-Fleming’s Right Hand Rule
-Components of a Generator
*Rotor
*Armature
*Coil
*Stator
*Field electromagnets
*Brushes
-A.C. generators
-Commercial A.C generators
-DC generators
-Principle
-Working
-Differences between AC and DC
The document discusses synchronous generators and their operation. It covers:
- The two reaction theory which separates the armature mmf into direct and quadrature axis components.
- How phasor diagrams can be used to represent the direct and quadrature axis reactances (Xd and Xq).
- The slip test method to measure Xd and Xq by taking voltage-to-current ratios with the armature mmf aligned to each axis.
- Important cautions for the slip test including keeping slip extremely low to avoid errors from damper windings or open circuit voltages reaching dangerous levels.
This document discusses the key components and operating principles of DC generators. It describes the essential parts of a practical generator including the magnetic frame, pole cores, field coils, armature core, armature windings, commutator, brushes and bearings. It also covers different types of armature windings such as lap and wave windings. Finally, it discusses losses that occur in DC generators and conditions for maximum efficiency.
This document discusses a study on the application of eddy current brakes in automobiles. It begins with an introduction to eddy current brakes, explaining that they slow objects by dissipating kinetic energy as heat using opposing eddy currents induced by a magnetic field. It then covers the principles and types of eddy current brakes, how they work using electromagnetic induction, their advantages like being non-mechanical and fully resettable, and their disadvantages like diminished braking force at low speeds. It concludes by discussing applications of eddy current brakes for additional safety on long mountain descents and for high-speed vehicles.
This document provides an overview of eddy current brakes, including their introduction, types, working principle, advantages, disadvantages, applications, and future aspects. Eddy current brakes use electromagnetic induction to generate closed loops of eddy currents in a conductive material, like a metal disc attached to a vehicle's wheel. This creates counter magnetic fields that oppose the motion of the conductor to generate braking force without contact. The document discusses two main types - linear brakes that induce eddy currents in rails, and circular brakes that use a conductive disc. Applications include trains, roller coasters, and other machinery where contact-based braking could wear out.
The document discusses the key components of AC generators, including the field, armature, prime mover, rotor, and stator. It explains that the field produces a magnetic flux, the armature produces voltage as this flux cuts through it, and the prime mover provides rotational power. There are two main types of AC generators - those with a stationary field and rotating armature, and those with a rotating field and stationary armature. The rotating field, stationary armature type is commonly used for large power generation.
Electric motors and generators both use the principle of electromagnetic induction to convert between electrical and mechanical energy. Electric motors convert electrical energy into mechanical motion by using a rotating electromagnet within a magnetic field, while electric generators convert mechanical energy into electrical current by rotating a coil of wire within a magnetic field. The key components needed for both are an electrical coil, a magnetic field, and a way to transfer the induced current such as slip rings or a commutator.
This document discusses different types of motors, including DC motors, AC motors, and servo motors. It describes the key components and characteristics of series, shunt, and compound DC motors. It also explains induction motors, synchronous motors, and the differences between squirrel cage and wound rotors. AC motors are divided into synchronous and induction types. Servo motors are described as incorporating a DC motor, gear train, potentiometer, and control circuit to enable precise angular positioning. Common applications of different motor types are also mentioned.
Construction and components of DC Machine – Principle of operation – Lap and wave windings-EMF equations– circuit model – armature reaction –methods of excitationcommutation – interpoles compensating winding –characteristics of DC generators.
A solenoid is a coil of wire that produces a magnetic field when electric current passes through it. Inside the solenoid, the magnetic field lines are parallel and uniform. Outside the solenoid, the magnetic field is non-uniform and weak due to cancellation of opposing field lines between coil turns. Solenoids can operate using direct current (DC) or alternating current (AC). DC solenoids consist of a coil, field/helix, and plunger that moves in one direction when energized. Solenoids have many applications including locking mechanisms, automotive systems, medical devices, railways, and industrial machinery.
An AC generator converts mechanical energy to electrical energy by rotating a coil within a magnetic field or rotating the magnetic field around a stationary coil. It produces alternating current unlike a DC generator. The main components of an AC generator are the field, armature, prime mover, rotor, and stator. The rotor is driven by the prime mover and either the rotor or stator contains the field coils. Losses in the AC generator occur due to resistance in the armature windings, hysteresis in the iron cores, and mechanical friction from bearings and windage. The efficiency of an AC generator is the ratio of its output power to input power.
A DC generator converts mechanical energy into electrical energy through electromagnetic induction according to Faraday's Laws. It has two main parts: a magnetic field and conductors. When the conductors move within the magnetic field, a voltage is induced across the conductors and electrical energy is generated.
This document discusses the components and operation of an AC generator. It describes the key parts including the field, armature, prime mover, rotor, stator and slip rings. The field and magnetic flux produce voltage in the armature. The rotor is driven by the prime mover and its rotation through the magnetic field induces current in the armature coils. Slip rings allow current to flow in and out of the rotating component. AC generators have advantages over DC generators for applications such as power generation.
This document provides a summary of a project report on industrial automation in 2015 focusing on AC and DC motors and transformers. It includes sections on acknowledging those who provided guidance, the contents which discuss principles and construction of DC motors, AC motors, and transformers. For DC motors, it explains types including series, shunt, and compound, as well as construction details and speed control methods. For transformers, it discusses working principles, types by construction, voltage transformation ratios, and equivalent circuits. It also provides overviews of induction motors and synchronous motors as types of AC machines.
Eddy current brakes work by generating eddy currents in a conductor when it moves through a changing magnetic field. This induces an opposing magnetic field that creates a braking force based on Lenz's law. There are two main types - circular brakes with a disc between electromagnet poles, and linear brakes using a rail and magnetic yoke. Advantages include no wear, adjustable braking, and being lightweight; disadvantages are reduced braking at low speeds and difficulty designing and simulating the system. Applications include high speed trains and roller coasters.
The document provides information about solenoids and DC motors. It defines a solenoid as a coil that produces a magnetic field when electric current passes through it. Solenoids are used to create controlled magnetic fields and can act as electromagnets. The document also describes various applications of solenoids such as in valves, switches, starters, and linear actuators. It then discusses DC motors and how they work using electromagnetic principles and a commutator to reverse polarity and keep the motor rotating. A fan regulator circuit is also shown that uses a variable resistor to control current and dim a lamp.
Mrs. Dharani Venkatesh provided guidance and support to help the student successfully complete their physics project. The Principal, Vice Principal, and Correspondent also supported the student by giving them the opportunity to do this mini project. Finally, the student's parents and friends helped finalize the project within the limited time frame.
We have designed a Wind Generator as our final year Engineering project. For information please go through the presentation or else you can contact me. Feel free to give your valued suggestions
The document discusses alternating current, how it is generated using electromagnetic induction from rotating coils in magnetic fields, and the working principles of AC generators used widely in power plants and vehicles to convert mechanical energy into electrical energy for power grids and other applications. Major topics covered include the differences between AC and DC, methods for changing magnetic flux to generate AC, components and efficiency of AC generators, and their predominant uses.
Anushika Kapoor submitted a physics project report on AC generators to her teacher Mr. Vipin Mishra. The report describes the key components of an AC generator including the coil, magnetic field, slip rings, and brushes. It explains the working principle of electromagnetic induction and how an alternating current is produced as the coil rotates perpendicularly to the magnetic field. Applications of AC generators include bicycles, electric scooters, microwaves, and sailboats.
IRJET- Implementation of Lenz Law for the Application of Electromagnetic ...IRJET Journal
The document summarizes the implementation of Lenz's law for an electromagnetic disk braking system. It discusses how an electromagnet produces a magnetic field when powered by a current, inducing eddy currents in a rotating disk that generate a drag force opposing the disk's motion. The system is designed to slow rotation without friction by converting kinetic energy to heat in the disk. A prototype is constructed and tested, showing it can reduce the disk's speed from 340 to 31 RPM within 4-6 seconds using a 24V power supply. While heating is not a problem in the disk, the electromagnets' coils do heat up. Further optimization is needed to apply braking more quickly while preventing overheating.
The document summarizes the Searl Effect Generator (SEG), a device invented by John Searl in 1946 that aims to provide unlimited clean energy. The SEG consists of concentric rings and magnetic rollers that spin perpetually due to interactions between the materials, including magnets, neodymium, and copper. When constructed correctly, these materials create a cycle of electron movement that produces more power than the device uses. The SEG works by using ambient temperature changes to power the rotation of magnetic rollers around concentric rings, inducing electric currents that can power external loads. The document describes the experimental setup of a one-ring SEG device constructed and tested based on Searl's theories.
Searl-Effect Generator Design and Manufacturing Procedure
In this article, the design and manufacturing procedure for a Searl-Effect Generator (SEG) will be described. The SEG is a device that generates electricity using principles of magnetism and rotation. The generator consists of three main parts: the rotor, the stator, and the housing. The rotor is a metal disc that rotates around a stationary stator. The stator is made up of two electromagnets that create a rotating magnetic field. The housing holds everything together and provides a place for the wiring to connect to the generator.
The first step in building the SEG is to create the rotor. The rotor is made from a metal disc that is about 12 inches in diameter. A hole must be drilled in the center of the disc so that it can fit over the axle of the motor.
This document discusses the development of a multi-purpose machine using a Scotch yoke mechanism. It begins with an introduction to multi-operation machines and the Scotch yoke mechanism. It then discusses the construction and working principle of the Scotch yoke, including how rotational motion is converted to reciprocating motion. The document continues with sections on the apparatus used, including DC motors, principles of DC motor operation, brushed DC motors, brushless DC motors, and DC servo motors. It concludes with a discussion of DC motor behavior and factors such as high speed output, back EMF, and noise on power lines.
DESIGN AND FABRICATION OF PLANETARY DRIVE MAGNET PEDAL POWER HUB-DYNAMOmsejjournal
This paper presents a low speed permanent magnetic based generator which is suitable for supplying
generating power from bicycle motion and application in providing energy for bicycle front and rear lights
or electronics devices.The dynamo have a hub axel, a hub housing rotatable mounted around the hub axel
with bearing, a planetary drive that increases the rotational speed of the permanent magnet, and the
power generating mechanism with coil fitted to hub axel that has connected to the output connector. In
such a hub dynamo, the magnet rotates faster than the bicycle wheel so that power output is high even at
the normal bicycle speeds.
This document describes the design and development of an electromagnetic and automatic braking system. It provides an introduction to the project, lists the main components used including discs, DC motors, electromagnets and sensors. It discusses the working principle of eddy currents in electromagnetic braking. The document reviews previous literature on related braking systems and outlines the types of brakes. It also includes the construction, advantages and applications of the system as well as a proposed methodology and references.
This document is a seminar report submitted by Dipendra Singh to partially fulfill the requirements for a Bachelor of Technology degree. It discusses eddy current brakes, which use electromagnetic induction to generate opposing eddy currents in a conductor to produce a braking force. The report covers the basic principles of operation, construction details involving a stationary magnetic field system and rotating part, working mechanisms where cutting the magnetic field induces eddy currents, types including electrically excited and permanent magnet varieties, requirements, advantages, and applications such as in trains.
The document provides details on the motor/generator designed by Robert Adams that is capable of exceeding 100% efficiency. It describes the basic operating principles and specific configurations that allow it to achieve high performance, including the use of power collection coils, magnet and electromagnet proportions, switching mechanisms, and construction methods. The motor utilizes pulsed electromagnets and permanent magnets on the rotor to generate power through clever timing of the electrical pulses and harvesting of back EMF effects.
This document provides information on pulsed energy devices described by Patrick J. Kelly, specifically focusing on the motor/generator designed by Robert Adams. The summary is:
1) Robert Adams designed an electric motor that uses permanent magnets on the rotor and pulsed electromagnets on the stator. When configured correctly, the output power exceeds the input power by a large margin, such as 800%.
2) The device operates by using power collection coils positioned and timed to contribute back EMF to drive the rotor. Additional electromagnets are pulsed on and off to further boost efficiency beyond 100%.
3) Practical details are provided on components like magnet shape and size, coil dimensions, switching methods and
This Project was directed at creating an integrated electric motor and eddy current brake. This combination is designed to be used in the automotive industry as an electric all-wheel drive system that can be managed by available traction and stability control technology. This project addresses the physical concept of using an induced electromagnetic field to slow the proposed vehicle speed. The main goal is lessening the lifetime maintenance of a vehicle and eliminating several high maintenance items. This system is designed as a “frictionless” system and although it is not completely frictionless it eliminates the need for standard hydraulic brake pads and rotors which wear and fail due to friction material loss. This saves the consumer's time and money in maintenance.
Trackers direct solar panels or modules towards sun. These devices change their orientation throughout the day to follow the sun's path to maximize energy capture.In photovoltaic systems, trackers help minimize the angle of incidence (the angle that a ray of light makes with a line perpendicular to the surface) between the incoming light and the panel, which increases the amount of energy the installation produces. Concentrated solar photovoltaics and concentrated solar thermal have optics that directly accepts sunlight, so solar trackers must be angled correctly to collect energy
Transducer for Tension Force Measurement and Control of Fine-Winding MaterialsIDES Editor
In this paper has been designed a facility
(electromechanical system) for regulation the tension force
of winding fine materials. In winding fine strip material such
a thread it is important to get homogeneous density of the
wound package, to get high quality material in next processing
of this package. In order to achieve this goal, the designed
facility controls the thread tension force during winding
process and the driving motor speed. And it allows adjusting
the tension force of the winding thread to the desired value,
which is variable and depends on the radius of the package.
This gives the required homogeneous density of the wound
package material. The suggested facility consists of simple
electronic circuit, lever, pulley, electromagnetic coils and other
simple components. The suggested system is provided by an
adjusting element in order to set the tension force of winding
material at the required reference value.
This document discusses several types of electric motors: AC series motors, universal motors, stepper motors, and shaded pole motors. It provides details on the construction and operation of universal motors and stepper motors. Universal motors can operate on either AC or DC power because the rotor and stator windings are connected in series. Stepper motors rotate in precise angular increments in response to applied digital pulses, making them well-suited for applications requiring precise positional control like printers and CNC machines. The document compares advantages and disadvantages of stepper motors.
The document describes the fabrication of an electromagnetic braking system for a diploma in automobile engineering. It discusses the construction of the system including an MS fabricated stand, DC power supply with switch, electromagnetic coil unit, and braking unit. The system uses a 12V DC power supply and electromagnetic coil to pull a brake lever and apply the brake to a rotating wheel when the switch is engaged. It was submitted by 6 students under the guidance of their project guide for their diploma requirement.
The document outlines the course content for EECE-259, which covers electrical and electronics technology. The course covers principles and characteristics of DC generators, DC motors, AC generators/alternators, induction motors, synchronous motors, and transformers. It also discusses losses in generators and motor characteristics. Key references on electrical machinery fundamentals and AC/DC machines are provided.
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In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
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Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
There are 4 phases of wound healing: hemostasis, inflammation, proliferation, and remodeling. This document also describes the mechanism of wound healing. Factors that affect healing include infection, uncontrolled diabetes, poor nutrition, age, anemia, the presence of foreign bodies, etc.
Complications of wound healing like infection, hyperpigmentation of scar, contractures, and keloid formation.
🔥🔥🔥🔥🔥🔥🔥🔥🔥
إضغ بين إيديكم من أقوى الملازم التي صممتها
ملزمة تشريح الجهاز الهيكلي (نظري 3)
💀💀💀💀💀💀💀💀💀💀
تتميز هذهِ الملزمة بعِدة مُميزات :
1- مُترجمة ترجمة تُناسب جميع المستويات
2- تحتوي على 78 رسم توضيحي لكل كلمة موجودة بالملزمة (لكل كلمة !!!!)
#فهم_ماكو_درخ
3- دقة الكتابة والصور عالية جداً جداً جداً
4- هُنالك بعض المعلومات تم توضيحها بشكل تفصيلي جداً (تُعتبر لدى الطالب أو الطالبة بإنها معلومات مُبهمة ومع ذلك تم توضيح هذهِ المعلومات المُبهمة بشكل تفصيلي جداً
5- الملزمة تشرح نفسها ب نفسها بس تكلك تعال اقراني
6- تحتوي الملزمة في اول سلايد على خارطة تتضمن جميع تفرُعات معلومات الجهاز الهيكلي المذكورة في هذهِ الملزمة
واخيراً هذهِ الملزمة حلالٌ عليكم وإتمنى منكم إن تدعولي بالخير والصحة والعافية فقط
كل التوفيق زملائي وزميلاتي ، زميلكم محمد الذهبي 💊💊
🔥🔥🔥🔥🔥🔥🔥🔥🔥
Traditional Musical Instruments of Arunachal Pradesh and Uttar Pradesh - RAYH...
Summer Training Report on Maintenance of the Electric Loco's
1. GALAXY GLOBAL GROUP OF
INSTITUTIONS, DINARPUR (AMBALA)
To wards partial fulfillment of the requirement of K.U.K. for bachelor of
technology in Mechanical Engineering
REPORT ON
SOLENOID ELECTRIC ENGINE
SUBMITTED TO
ER. DEEPAK GUPTA
(PROJECT INCHARGE)
MR. N. GUPTA
H.O.D. (MECH.-ENGG.)
PROJECT GUIDE
ER. KRISHAN KANT
ER. MOHIT ASHRI
(ASSISTANT PROFESOR IN MECH. ENGG.)
SUBMITTED BY
ROHIT KUMAR 7309461
GURMEET SINGH 7309455
GURMAIL SINGH 7309456
SANJEEV KUMAR 7309454
AMIT KUMAR 7309449
1
2. CONSTRUCTION
Step-1
We are using ac solenoid coil in our project to give angular motion to our crank shaft.
Coil detail:
Brand: IDEAL -2.0kg/15mm rat,cont, a.c 220v
When we provide current to the coil it core.
2
3. Step-2
We design special crank shaft according to the solenoid coil. We use three iron dicks and
pass iron rode from it as shown below diagram.
Use bearing (608) on both side of crank shaft for support it on base and we use chain and
sprocket for transmit power to gear box.
3
7. Step-5
We design our project as 4 stork solenoid engine. For distribution different four stork
power we using simple technique, we use metal sheet and cut it in circular form then we
divide that circle in to 4 different portions as shown below and paste on wooden circular
piece.
7
8. Step-6
We make one hole in centre of that wooden piece and insert one dc gear motor in it. We
provide ac current to the motor shaft with help of insulator and attach one iron foil with
that shaft this foil is connected with on the other side as shown below diagram.
We are running dc motor with help of dc supply and dc motor shaft is controlling ac
current with help of insulator and transmit power supply to solenoid coil for crank shaft
movement.
Power supply of dc motor: we are using fan regulator for increase and decrease of
power supply which transmit to the 12v step down transformer. Now we receive 12 v ac
supply and we need 12dc supply so, we use bridge rectifier to convert ac to dc. As we
increase fan regulator speed our dc motor move fast, if we decrease its speed it move
slow. According to this our dick transmits power supply to solenoid coil and coil rotate to
crank shaft.
Step-6
8
9. Final look of model
CONPONENT USED
1. 4- Solenoid coil (ac coil)
2. Dc motor
9
10. 3. Power transmitting dick
4. Bearing
5. Crank shaft (design)
6. Washer
7. Gearbox
8. Chain and sprocket
9. Wheel
10. Wheel shaft
11. Wire
12. Body frame
Many more as per requirement…….
CONPONENT DETAIL
Used DC solenoid coil
10
11. Solenoid
A solenoid is a coil wound into a tightly packed helix. In physics, the term solenoid
refers to a long, thin loop of wire, often wrapped around a metallic core, which produces
a magnetic field when an electric current is passed through it. Solenoids are important
because they can create controlled magnetic fields and can be used as electromagnets.
The term solenoid refers specifically to a magnet designed to produce a uniform magnetic
field in a volume of space (where some experiment might be carried out).
11
12. In engineering, the term solenoid may also refer to a variety of transducer devices that
convert energy into linear motion. The term is also often used to refer to a solenoid
valve, which is an integrated device containing an electromechanical solenoid which
actuates either a pneumatic or hydraulic valve, or a solenoid switch, which is a specific
type of relay that internally uses an electromechanical solenoid to operate an electrical
switch; for example, an automobile starter solenoid, or a linear solenoid, which is an
electromechanical solenoid.
Magnetic field of a solenoid
Inside
This is a derivation of the magnetic field around a solenoid that is long enough so that
fringe effects can be ignored. In the diagram to the right, we immediately know that the
field points in the positive z direction inside the solenoid, and in the negative z direction
outside the solenoid.
A solenoid with 3 Ampèrian loops
We see this by applying the right hand grip rule for the field around a wire. If we wrap
our right hand around a wire with the thumb pointing in the direction of the current, the
curl of the fingers shows how the field behaves. Since we are dealing with a long
solenoid, all of the components of the magnetic field not pointing upwards cancel out by
symmetry. Outside, a similar cancellation occurs, and the field is only pointing
downwards.
Now consider imaginary the loop c that is located inside the solenoid. By Ampère's law,
we know that the line integral of B (the magnetic field vector) around this loop is zero,
since it encloses no electrical currents (it can be also assumed that the circuital electric
12
13. field passing through the loop is constant under such conditions: a constant or constantly
changing current through the solenoid). We have shown above that the field is pointing
upwards inside the solenoid, so the horizontal portions of loop c doesn't contribute
anything to the integral. Thus the integral of the up side 1 is equal to the integral of the
down side 2. Since we can arbitrarily change the dimensions of the loop and get the same
result, the only physical explanation is that the integrands are actually equal, that is, the
magnetic field inside the solenoid is radially uniform. Note, though, that nothing
prohibits it from varying longitudinally which in fact it does.
Applications
Electromechanical solenoids
A 1920 explanation of a commercial solenoid used as an electromechanical actuator
Electromechanical solenoids consist of an electromagnetically inductive coil, wound
around a movable steel or iron slug (termed the armature). The coil is shaped such that
the armature can be moved in and out of the center, altering the coil's inductance and
thereby becoming an electromagnet. The armature is used to provide a mechanical force
to some mechanism (such as controlling a pneumatic valve). Although typically weak
over anything but very short distances, solenoids may be controlled directly by a
controller circuit, and thus have very low reaction times.
13
14. The force applied to the armature is proportional to the change in inductance of the coil
with respect to the change in position of the armature, and the current flowing through the
coil (see Faraday's law of induction). The force applied to the armature will always
move the armature in a direction that increases the coil's inductance.
Electromechanical solenoids are commonly seen in electronic paintball markers,
pinball machines, dot matrix printers and fuel injectors.
Rotary solenoid
The rotary solenoid is an electromechanical device used to rotate a ratcheting mechanism
when power is applied. These were used in the 1950s for rotary snap-switch automation
in electromechanical controls. Repeated actuation of the rotary solenoid advances the
snap-switch forward one position. Two rotary actuators on opposite ends of the rotary
snap-switch shaft, can advance or reverse the switch position.
The rotary solenoid has a similar appearance to a linear solenoid, except that the core is
mounted in the center of a large flat disk, with two or three inclined grooves cut into the
underside of the disk. These grooves align with slots on the solenoid body, with ball
bearings in the grooves.
When the solenoid is activated, the core is drawn into the coil, and the disk rotates on the
ball bearings in the grooves as it moves towards the coil body. When power is removed, a
spring on the disk rotates it back to its starting position, also pulling the core out of the
coil.
Rotary voice coil
This is a rotational version of a solenoid. Typically the fixed magnet is on the outside,
and the coil part moves in an arc controlled by the current flow through the coils. Rotary
voice coils are widely employed in devices such as disk drives.
Pneumatic solenoid valves
A pneumatic solenoid valve is a switch for routing air to any pneumatic device, usually
an actuator, allowing a relatively small signal to control a large device. It is also the
interface between electronic controllers and pneumatic systems.
Hydraulic solenoid valves
Hydraulic solenoid valves are in general similar to pneumatic solenoid valves except
that they control the flow of hydraulic fluid (oil), often at around 3000 psi (210 bar, 21
MPa, 21 MN/m²). Hydraulic machinery uses solenoids to control the flow of oil to rams
or actuators to (for instance) bend sheets of titanium in aerospace manufacturing.
Solenoid-controlled valves are often used in irrigation systems, where a relatively weak
solenoid opens and closes a small pilot valve, which in turn activates the main valve by
14
15. applying fluid pressure to a piston or diaphragm that is mechanically coupled to the main
valve. Solenoids are also in everyday household items such as washing machines to
control the flow and amount of water into the drum.
Transmission solenoids control fluid flow through an automatic transmission and are
typically installed in the transmission valve body.
Automobile starter solenoid
In a car or truck, the starter solenoid is part of an automobile starting system. The starter
solenoid receives a large electric current from the car battery and a small electric
current from the ignition switch. When the ignition switch is turned on (i.e. when the key
is turned to start the car), the small electric current forces the starter solenoid to close a
pair of heavy contacts, thus relaying the large electric current to the starter motor.
Starter solenoids can also be built into the starter itself, often visible on the outside of the
starter. If a starter solenoid receives insufficient power from the battery, it will fail to start
the motor, and may produce a rapid 'clicking' or 'clacking' sound. This can be caused by
a low or dead battery, by corroded or loose connections in the cable, or by a broken or
damaged positive (red) cable from the battery. Any of these will result in some power to
the solenoid, but not enough to hold the heavy contacts closed, so the starter motor itself
never spins, and the engine does not start.
Gear box
Used gear box
15
16. Transmission (mechanics)
A Transmission or gearbox provides speed and torque conversions from a rotating power
source to another device using gear ratios. In British English the term transmission refers
to the whole drive train, including gearbox, clutch, prop shaft (for rear-wheel drive),
differential and final drive shafts. The most common use is in motor vehicles, where the
transmission adapts the output of the internal combustion engine to the drive wheels.
Such engines need to operate at a relatively high rotational speed, which is inappropriate
for starting, stopping, and slower travel. The transmission reduces the higher engine
speed to the slower wheel speed, increasing torque in the process. Transmissions are also
used on pedal bicycles, fixed machines, and anywhere else rotational speed and torque
needs to be adapted.
Often, a transmission will have multiple gear ratios (or simply "gears"), with the ability to
switch between them as speed varies. This switching may be done manually (by the
operator), or automatically. Directional (forward and reverse) control may also be
provided. Single-ratio transmissions also exist, which simply change the speed and torque
(and sometimes direction) of motor output.
In motor vehicle applications, the transmission will generally be connected to the
crankshaft of the engine. The output of the transmission is transmitted via driveshaft to
one or more differentials, which in turn drive the wheels. While a differential may also
provide gear reduction, its primary purpose is to change the direction of rotation.
Conventional gear/belt transmissions are not the only mechanism for speed/torque
adaptation. Alternative mechanisms include torque converters and power transformation.
Uses
16
17. Gearboxes have found use in a wide variety of different—often stationary—applications,
such as wind turbines.
Transmissions are also used in agricultural, industrial, construction, mining and
automotive equipment. In addition to ordinary transmission equipped with gears, such
equipment makes extensive use of the hydrostatic drive and electrical adjustable-speed
drives.
BEARINGS
Have you ever wondered how things like inline skate wheels and electric motors spin so
smoothly and quietly? The answer can be found in a neat little machine called a bearing.
A tapered roller bearing from a manual transmission
The bearing makes many of the machines we use every day possible. Without bearings,
we would be constantly replacing parts that wore out from friction. In this article, we'll
learn how bearings work, look at some different kinds of bearings and explain their
common uses, and explore some other interesting uses of bearings.
THE BASICS
The concept behind a bearing is very simple: Things roll better than they slide. The
wheels on your car are like big bearings. If you had something like skis instead of wheels,
your car would be a lot more difficult to push down the road.
17
18. That is because when things slide, the friction between them causes a force that tends to
slow them down. But if the two surfaces can roll over each other, the friction is greatly
reduced.
Bearings reduce friction by providing smooth metal balls or rollers, and a smooth inner
and outer metal surface for the balls to roll against. These balls or rollers "bear" the load,
allowing the device to spin smoothly.
Bearing Loads
Bearings typically have to deal with two kinds of loading, radial and thrust. Depending
on where the bearing is being used, it may see all radial loading, all thrust loading or a
combination of both.
The bearings that support the shafts of motors and pulleys are subject to a radial load.
The bearings in the electric motor and the pulley pictured above face only a radial load.
In this case, most of the load comes from the tension in the belt connecting the two
pulleys.
18
19. The bearings in this stool are subject to a thrust load.
The bearing above is like the one in a barstool. It is loaded purely in thrust, and the entire
load comes from the weight of the person sitting on the stool.
The bearings in a car wheel are subject to both thrust and
radial loads.
The bearing above is like the one in the hub of your car wheel. This bearing has to
support both a radial load and a thrust load. The radial load comes from the weight of the
car, the thrust load comes from the cornering forces when you go around a turn.
Types of Bearings
There are many types of bearings, each used for different purposes. These include ball
bearings, roller bearings, ball thrust bearings, roller thrust bearings and tapered roller
thrust bearings.
19
20. Ball Bearings
Ball bearings, as shown below, are probably the most common type of bearing. They are
found in everything from inline skates to hard drives. These bearings can handle both
radial and thrust loads, and is usually found in applications where the load is relatively
small.
Cutaway view of a ball bearing
In a ball bearing, the load is transmitted from the outer race to the ball and from the ball
to the inner race. Since the ball is a sphere, it only contacts the inner and outer race at a
very small point, which helps it spin very smoothly. But it also means that there is not
very much contact area holding that load, so if the bearing is overloaded, the balls can
deform or squish, ruining the bearing.
20
21. DC MOTORS
DC GEAR MOTOR
Brand HOSIDEN motors (Japan)
R.P.M: 75-100
VOLT: 12-18V. DC
One of the first electromagnetic rotary motors was invented by Michael Faraday in 1821
and consisted of a free-hanging wire dipping into a pool of mercury. A permanent magnet
was placed in the middle of the pool of mercury. When a current was passed through the
wire, the wire rotated around the magnet, showing that the current gave rise to a circular
magnetic field around the wire. This motor is often demonstrated in school physics
classes, but brine (salt water) is sometimes used in place of the toxic mercury. This is the
simplest form of a class of electric motors called homopolar motors. A later refinement is
the Barlow's Wheel.
Another early electric motor design used a reciprocating plunger inside a switched
solenoid; conceptually it could be viewed as an electromagnetic version of a two stroke
internal combustion engine.
The modern DC motor was invented by accident in 1873, when Zénobe Gramme
connected a spinning dynamo to a second similar unit, driving it as a motor.
The classic DC motor has a rotating armature in the form of an electromagnet. A rotary
switch called a commutator reverses the direction of the electric current twice every
cycle, to flow through the armature so that the poles of the electromagnet push and pull
against the permanent magnets on the outside of the motor. As the poles of the armature
electromagnet pass the poles of the permanent magnets, the commutator reverses the
21
22. polarity of the armature electromagnet. During that instant of switching polarity, inertia
keeps the classical motor going in the proper direction. (See the diagrams below.)
A simple DC electric motor. When the coil is powered, a magnetic field is generated
around the armature. The left side of the armature is pushed away from the left magnet
and drawn toward the right, causing rotation.
The armature continues to rotate.
22
23. When the armature becomes horizontally aligned, the commutator reverses the direction
of current through the coil, reversing the magnetic field. The process then repeats.
Fan Regulator
Description .
This is the circuit diagram of the simplest lamp dimmer or fan regulator. The circuit is
based on the principle of power control using a Triac. The circuit works by varying the
firing angle of the Triac . Resistors R1, R2 and capacitor C2 are associated with this. The
firing angle can be varied by varying the value of any of these components. Here R1 is
selected as the variable element .By varying the value of R1 the firing angle of Triac
changes (in simple words, how much time should Triac conduct) changes. This directly
varies the load power, since load is driven by Triac. The firing pulses are given to the
gate of Triac T1 using Diac D1.
Notes
Assemble the circuit on a good quality PCB or common board. The load whether lamp
,fan or any thing ,should be less than 200 Watts. To connect higher loads replace the
Triac BT 136 with a higher Watt capacity Triac. All parts of the circuit are active with
potential shock hazard. So be careful.
I advice to test the circuit with a low voltage supply (say 12V or 24V AC) and a
small load (a same volt bulb) ,before connecting the circuit to mains.
Parts List
23
24. R1 1o K 1 Watt Resistor
R2 1o0 K Potentiometer (Variable Resistance)
C1 0.1 uF (500V or above) Polyester Capacitor
T1 BT 136 Triac
D1 DB2 Diac
24
25. POWER SUPPLY
In alternating current the electron flow is alternate, i.e. the electron flow increases
to maximum in one direction, decreases back to zero. It then increases in the other
direction and then decreases to zero again. Direct current flows in one direction only.
Rectifier converts alternating current to flow in one direction only. When the anode of the
diode is positive with respect to its cathode, it is forward biased, allowing current to flow.
But when its anode is negative with respect to the cathode, it is reverse biased and does
not allow current to flow. This unidirectional property of the diode is useful for
rectification. A single diode arranged back-to-back might allow the electrons to flow
during positive half cycles only and suppress the negative half cycles. Double diodes
arranged back-to-back might act as full wave rectifiers as they may allow the electron
flow during both positive and negative half cycles. Four diodes can be arranged to make a
full wave bridge rectifier. Different types of filter circuits are used to smooth out the
pulsations in amplitude of the output voltage from a rectifier. The property of capacitor to
oppose any change in the voltage applied across them by storing energy in the electric
field of the capacitor and of inductors to oppose any change in the current flowing
25
26. through them by storing energy in the magnetic field of coil may be utilized. To remove
pulsation of the direct current obtained from the rectifier, different types of combination
of capacitor, inductors and resistors may be also be used to increase to action of filtering.
NEED OF POWER SUPPLY
Perhaps all of you are aware that a ‘power supply’ is a primary requirement for
the ‘Test Bench’ of a home experimenter’s mini lab. A battery eliminator can eliminate
or replace the batteries of solid-state electronic equipment and the equipment thus can be
operated by 230v A.C. mains instead of the batteries or dry cells. Nowadays, the use of
commercial battery eliminator or power supply unit has become increasingly popular as
power source for household appliances like transreceivers, record player, cassette players,
digital clock etc.
THEORY
USE OF DIODES IN RECTIFIERS:
Electric energy is available in homes and industries in India, in the form of
alternating voltage. The supply has a voltage of 220V (rms) at a frequency of 50 Hz. In
the USA, it is 110V at 60 Hz. For the operation of most of the devices in electronic
equipment, a dc voltage is needed. For instance, a transistor radio requires a dc supply for
its operation. Usually, this supply is provided by dry cells. But sometime we use a battery
eliminator in place of dry cells. The battery eliminator converts the ac voltage into dc
voltage and thus eliminates the need for dry cells. Nowadays, almost all-electronic
equipment includes a circuit that converts ac voltage of mains supply into dc voltage.
This part of the equipment is called Power Supply. In general, at the input of the power
supply, there is a power transformer. It is followed by a diode circuit called Rectifier. The
output of the rectifier goes to a smoothing filter, and then to a voltage regulator circuit.
The rectifier circuit is the heart of a power supply.
Rectification
Rectification is a process of rendering an alternating current or voltage into a
unidirectional one. The component used for rectification is called ‘Rectifier’. A rectifier
permits current to flow only during the positive half cycles of the applied AC voltage by
eliminating the negative half cycles or alternations of the applied AC voltage. Thus
26
27. pulsating DC is obtained. To obtain smooth DC power, additional filter circuits are
required.
A diode can be used as rectifier. There are various types of diodes. But,
semiconductor diodes are very popularly used as rectifiers. A semiconductor diode is a
solid-state device consisting of two elements is being an electron emitter or cathode, the
other an electron collector or anode. Since electrons in a semiconductor diode can flow in
one direction only-from emitter to collector- the diode provides the unilateral conduction
necessary for rectification. Out of the semiconductor diodes, copper oxide and selenium
rectifier are also commonly used.
FULL WAVE RECTIFIER
It is possible to rectify both alternations of the input voltage by using two diodes
in the circuit arrangement. Assume 6.3 V rms (18 V p-p) is applied to the circuit. Assume
further that two equal-valued series-connected resistors R are placed in parallel with the
ac source. The 18 V p-p appears across the two resistors connected between points AC
and CB, and point C is the electrical midpoint between A and B. Hence 9 V p-p appears
across each resistor. At any moment during a cycle of v in, if point A is positive relative
to C, point B is negative relative to C. When A is negative to C, point B is positive
relative to C. The effective voltage in proper time phase which each diode "sees" is in
Fig. The voltage applied to the anode of each diode is equal but opposite in polarity at
any given instant.
When A is positive relative to C, the anode of D 1 is positive with respect to its
cathode. Hence D1 will conduct but D2 will not. During the second alternation, B is
positive relative to C. The anode of D2 is therefore positive with respect to its cathode,
and D2 conducts while D1 is cut off.
There is conduction then by either D1 or D2 during the entire input-voltage cycle.
Since the two diodes have a common-cathode load resistor R L, the output voltage
across RL will result from the alternate conduction of D1 and D2. The output waveform
vout across RL, therefore has no gaps as in the case of the half-wave rectifier.
The output of a full-wave rectifier is also pulsating direct current. In the diagram,
the two equal resistors R across the input voltage are necessary to provide a voltage
midpoint C for circuit connection and zero reference. Note that the load resistor R L is
connected from the cathodes to this center reference point C.
An interesting fact about the output waveform vout is that its peak amplitude is
not 9 V as in the case of the half-wave rectifier using the same power source, but is less
27
28. than 4½ V. The reason, of course, is that the peak positive voltage of A relative to C is
4½ V, not 9 V, and part of the 4½ V is lost across R.
Though the full wave rectifier fills in the conduction gaps, it delivers less than
half the peak output voltage that results from half-wave rectification.
BRIDGE RECTIFIER
A more widely used full-wave rectifier circuit is the bridge rectifier. It requires
four diodes instead of two, but avoids the need for a centre-tapped transformer. During
the positive half-cycle of the secondary voltage, diodes D2 and D4 are conducting and
diodes D1 and D3 are non-conducting. Therefore, current flows through the secondary
winding, diode D2, load resistor RL and diode D4. During negative half-cycles of the
secondary voltage, diodes D1 and D3 conduct, and the diodes D2 and D4 do not conduct.
The current therefore flows through the secondary winding, diode D1, load resistor RL
and diode D3. In both cases, the current passes through the load resistor in the same
direction. Therefore, a fluctuating, unidirectional voltage is developed across the load.
FILTRATION
The rectifier circuits we have discussed above deliver an output voltage that
always has the same polarity: but however, this output is not suitable as DC power supply
for solid-state circuits. This is due to the pulsation or ripples of the output voltage. This
should be removed out before the output voltage can be supplied to any circuit. This
smoothing is done by incorporating filter networks. The filter network consists of
inductors and capacitors. The inductors or choke coils are generally connected in series
with the rectifier output and the load. The inductors oppose any change in the magnitude
of a current flowing through them by storing up energy in a magnetic field. An inductor
offers very low resistance for DC whereas; it offers very high resistance to AC. Thus, a
series connected choke coil in a rectifier circuit helps to reduce the pulsations or ripples
to a great extent in the output voltage. The fitter capacitors are usually connected in
parallel with the rectifier output and the load. As AC can pass through a capacitor but DC
cannot, the ripples are thus limited and the output becomes smoothed. When the voltage
across its plates tends to rise, it stores up energy back into voltage and current. Thus, the
fluctuations in the output voltage are reduced considerable. Filter network circuits may be
of two types in general:
CHOKE INPUT FILTER
If a choke coil or an inductor is used as the ‘first- components’ in the filter
network, the filter is called ‘choke input filter’. The D.C. along with AC pulsation from
the rectifier circuit at first passes through the choke (L). It opposes the AC pulsations but
allows the DC to pass through it freely. Thus AC pulsations are largely reduced. The
further ripples are by passed through the parallel capacitor C. But, however, a little nipple
28
29. remains unaffected, which are considered negligible. This little ripple may be reduced by
incorporating a series a choke input filters.
CAPACITOR INPUT FILTER
If a capacitor is placed before the inductors of a choke-input filter network, the
filter is called capacitor input filter. The D.C. along with AC ripples from the rectifier
circuit starts charging the capacitor C. to about peak value. The AC ripples are then
diminished slightly. Now the capacitor C, discharges through the inductor or choke coil,
which opposes the AC ripples, except the DC. The second capacitor C by passes the
further AC ripples. A small ripple is still present in the output of DC, which may be
reduced by adding additional filter network in series.
CIRCUIT DIAGRAM
29
30. Transformer
A transformer is an electrical device that transfers energy from one circuit to another by
magnetic coupling with no moving parts. A transformer comprises two or more coupled
windings, or a single tapped winding and, in most cases, a magnetic core to concentrate
magnetic flux. A changing current in one winding creates a time-varying magnetic flux in
the core, which induces a voltage in the other windings. Michael Faraday built the first
transformer, although he used it only to demonstrate the principle of electromagnetic
induction and did not foresee the use to which it would eventually be put.
30
31. Three-phase pole-mounted step-down transformer.
A historical Stanley transformer.
• Lucien Gaulard and John Dixon Gibbs, who first exhibited a device called a
'secondary generator' in London in 1881 and then sold the idea to American
company Westinghouse. This may have been the first practical power
transformer. They also exhibited the invention in Turin in 1884, where it was
adopted for an electric lighting system. Their early devices used an open iron
core, which was soon abandoned in favour of a more efficient circular core with a
closed magnetic path.
• William Stanley, an engineer for Westinghouse, who built the first practical
device in 1885 after George Westinghouse bought Gaulard and Gibbs' patents.
31
32. The core was made from interlocking E-shaped iron plates. This design was first
used commercially in 1886.
• Hungarian engineers Károly Zipernowsky, Ottó Bláthy and Miksa Déri at the
Ganz company in Budapest in 1885, who created the efficient "ZBD" model
based on the design by Gaulard and Gibbs.
• Nikola Tesla in 1891 invented the Tesla coil, which is a high-voltage, air-core,
dual-tuned resonant transformer for generating very high voltages at high
frequency.
OVERVIEW
The transformer is one of the simplest of electrical devices, yet transformer designs and
materials continue to be improved. Transformers are essential for high voltage power
transmission, which makes long distance transmission economically practical. This
advantage was the principal factor in the selection of alternating current power
transmission in the "War of Currents" in the late 1880s.
Audio frequency transformers (at the time called repeating coils) were used by the
earliest experimenters in the development of the telephone. While some electronics
applications of the transformer have been made obsolete by new technologies,
transformers are still found in many electronic devices.
Transformers come in a range of sizes from a thumbnail-sized coupling transformer
hidden inside a stage microphone to huge giga watt units used to interconnect large
portions of national power grids. All operate with the same basic principles and with
many similarities in their parts.
Single phase pole-mounted step-down transformer
32
33. Transformers alone cannot do the following:
• Convert DC to AC or vice versa
• Change the voltage or current of DC
• Change the AC supply frequency.
However, transformers are components of the systems that perform all these functions.
AN ANALOGY
The transformer may be considered as a simple two-wheel 'gearbox' for electrical voltage
and current. The primary winding is analogous to the input shaft and the secondary
winding to the output shaft. In this analogy, current is equivalent to shaft speed, voltage
to shaft torque. In a gearbox, mechanical power (torque multiplied by speed) is constant
(neglecting losses) and is equivalent to electrical power (voltage multiplied by current)
which is also constant.
The gear ratio is equivalent to the transformer step-up or step-down ratio. A step-up
transformer acts analogously to a reduction gear (in which mechanical power is
transferred from a small, rapidly rotating gear to a large, slowly rotating gear): it trades
current (speed) for voltage (torque), by transferring power from a primary coil to a
secondary coil having more turns. A step-down transformer acts analogously to a
multiplier gear (in which mechanical power is transferred from a large gear to a small
gear): it trades voltage (torque) for current (speed), by transferring power from a primary
coil to a secondary coil having fewer turns.
COUPLING BY MUTUAL INDUCTION
A simple transformer consists of two electrical conductors called the primary winding
and the secondary winding. Energy is coupled between the windings by the time-varying
magnetic flux that passes through (links) both primary and secondary windings. When
the current in a coil is switched on or off or changed, a voltage is induced in a
neighboring coil. The effect, called mutual inductance, is an example of electromagnetic
induction.
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34. SIMPLIFIED ANALYSIS
A practical step-down transformer showing magnetising flux in the core
If a time-varying voltage is applied to the primary winding of turns, a current will
flow in it producing a magnetomotive force (MMF). Just as an electromotive force
(EMF) drives current around an electric circuit, so MMF tries to drive magnetic flux
through a magnetic circuit. The primary MMF produces a varying magnetic flux in
the core, and, with an open circuit secondary winding, induces a back electromotive
force (EMF) in opposition to . In accordance with Faraday's law of induction, the
voltage induced across the primary winding is proportional to the rate of change of flux:
and
where
• vP and vS are the voltages across the primary winding and secondary winding,
• NP and NS are the numbers of turns in the primary winding and secondary
winding,
• dΦP / dt and dΦS / dt are the derivatives of the flux with respect to time of the
primary and secondary windings.
Saying that the primary and secondary windings are perfectly coupled is equivalent to
saying that . Substituting and solving for the voltages shows that:
where
34
35. • vp and vs are voltages across primary and secondary,
• Np and Ns are the numbers of turns in the primary and secondary, respectively.
Hence in an ideal transformer, the ratio of the primary and secondary voltages is equal to
the ratio of the number of turns in their windings, or alternatively, the voltage per turn is
the same for both windings. The ratio of the currents in the primary and secondary
circuits is inversely proportional to the turns ratio. This leads to the most common use of
the transformer: to convert electrical energy at one voltage to energy at a different voltage
by means of windings with different numbers of turns. In a practical transformer, the
higher-voltage winding will have more turns, of smaller conductor cross-section, than the
lower-voltage windings.
The EMF in the secondary winding, if connected to an electrical circuit, will cause
current to flow in the secondary circuit. The MMF produced by current in the secondary
opposes the MMF of the primary and so tends to cancel the flux in the core. Since the
reduced flux reduces the EMF induced in the primary winding, increased current flows in
the primary circuit. The resulting increase in MMF due to the primary current offsets the
effect of the opposing secondary MMF. In this way, the electrical energy fed into the
primary winding is delivered to the secondary winding. Also because of this, the flux
density will always stay the same as long as the primary voltage is steady.
For example, suppose a power of 50 watts is supplied to a resistive load from a
transformer with a turns ratio of 25:2.
• P = EI (power = electromotive force × current)
50 W = 2 V × 25 A in the primary circuit if the load is a resistive load. (See note
1)
• Now with transformer change:
50 W = 25 V × 2 A in the secondary circuit.
ANALYSIS OF THE IDEAL TRANSFORMER
This treats the windings as a pair of mutually coupled coils with both primary and
secondary windings passing currents and with each coil linked with the same magnetic
flux. In an ideal transformer the core requires no MMF. The primary and secondary
MMFs, acting in opposite directions, are exactly balancing each other and hence, there is
no overall resultant MMF acting on the core. There is, however, no need for any MMF
acting on the core of an ideal transformer to create a magnetic flux. The flux in the core is
unambiguously determined by the applied primary voltage in accordance with Faraday's
law of induction, or rather by an integration of the aforesaid law.
In the ideal transformer at no load, i.e. with the secondary load removed, the voltage
applied to the primary winding is opposed by an induced EMF in the winding equal to the
applied voltage in accordance with Faraday's law of induction. No current will flow in
35
36. the winding since no MMF is required by the core. One might also say that the
inductance of the primary winding at no load is infinitely large.
Further on, the balance of the primary and secondary MMFs i.e. NPiP = NSiS , gives the
ratio of the secondary and primary currents as:
That is, the ratio between the primary and secondary currents is the inverse of the ratio
between the corresponding voltages.
DC VOLTAGES AND CURRENTS
A DC voltage applied to a winding of an ideal transformer will cause a DC voltage to be
induced in the other winding. This is because any voltage applied will create a changing
flux. However, using a transformer with DC voltages would require the magnetic flux in
the core (and current supplied by the DC voltage source) to increase without bound. If
there is resistance in the winding, the final current and final flux will be limited by that.
Once the flux stops changing, no voltage is induced in the other winding. If the core is
made of anything other than air (e.g. iron) it will also saturate. Saturation will drastically
reduce the amount of power that can be transferred, as well as causing the current to rise
even more steeply. For these reasons it is very important to avoid having any DC
component in the voltages being applied to a transformer. The amount of power being
dissipated in the winding will be limited solely by the winding resistance.
It is possible to draw DC current from a transformer, as a DC current merely represents a
constant offset to the flux in the core. DC currents are caused by some non-linear loads
(e.g. a half-wave rectifier). Most transformers are designed to be driven to near
saturation without any DC current components, so having a DC current will make the
transformer saturate more easily. Full-wave rectifiers do not have this issue, since the
current they draw has no DC component.
THE UNIVERSAL EMF EQUATION
If the flux in the core is sinusoidal, the relationship for either winding between its
number of turns, voltage, magnetic flux density and core cross-sectional area is given by
the universal emf equation (from Faraday's law):
36
37. where
• E is the sinusoidal rms or root mean square voltage of the winding,
• f is the frequency in hertz,
• N is the number of turns of wire on the winding,
• a is the cross-sectional area of the core in square metres
• B is the peak magnetic flux density in teslas,
Other consistent systems of units can be used with the appropriate conversions in the
equation.
Practical considerations
CLASSIFICATIONS
Transformers are adapted to numerous engineering applications and may be classified in
many ways:
• By power level (from fraction of a volt-ampere(VA) to over a thousand MVA),
• By application (power supply, impedance matching, circuit isolation),
• By frequency range (power, audio, radio frequency(RF))
• By voltage class (a few volts to about 750 kilovolts)
• By cooling type (air cooled, oil filled, fan cooled, water cooled, etc.)
• By purpose (distribution, rectifier, arc furnace, amplifier output, etc.).
• By ratio of the number of turns in the coils
• Step-up
The secondary has more turns than the primary.
• Step-down
The secondary has fewer turns than the primary.
• Isolating
Intended to transform from one voltage to the same voltage. The two coils have
approximately equal numbers of turns, although often there is a slight difference
in the number of turns, in order to compensate for losses (otherwise the output
voltage would be a little less than, rather than the same as, the input voltage).
• Variable
The primary and secondary have an adjustable number of turns which can be
selected without reconnecting the transformer.
37
38. CIRCUIT SYMBOLS
Standard symbols
Transformer with two windings and iron core.
Transformer with three windings.
The dots show the relative winding configuration of the windings.
Step-down or step-up transformer.
The symbol shows which winding has more turns,
but does not usually show the exact ratio.
Transformer with electrostatic screen,
which prevents capacitive coupling between the windings.
BIKE TIMING CHAIN
38
39. DIAMENSION:
LENTH: 560MM
GROOVE: 84
BIKE TIMING GEAR
DIAMENSION:
TEETH: 28
LENTH: 60MM
Two of the three books mentioned in the lead-up to this page, "Model Making for Young
Physicists" by A.D.Bulman and "The Boy Electrician" by Alfred P. Morgan, each
presented a model which could be described as a "Solenoid Engine". The most obvious
difference between them is that one of them (Bulman's) had only one solenoid, while
Morgan's had two. The most obvious thing that they had in common is that they both
relied on moving contacts.
39
40. Having built my two-pole electric motor, and thus knowing the hassles moving contacts
can cause, I decided in 2010 to build a solenoid engine built on very different principles.
The fact is, my …. and I did build a four-solenoid engine in the late 1960's, based
somewhat along the lines of Bulman's model, using an old solenoid my ………… had
lying around (goodness only knows where he got it from, or what its original function
was!). The model did work, although not very well; eventually it was dismantled, and
some of the parts found other uses. As you've probably guessed, the moving contacts
were the main cause of its ultimate demise.
Reduced to its bare essentials, a solenoid engine of the moving-contact type can be
represented as in the following diagram:
At the right is the solenoid - a coil of wire wound on a tube of suitable non-ferrous
material with a movable soft-iron core. This is attached to a crankshaft (at left) which
bears a slip-ring and a cam, both made from some suitable metal (eg. brass) and
electrically connected together.
40