This document presents information on cycloconverters. It begins by defining a cycloconverter as a type of AC-AC converter that converts alternating current (AC) from one frequency to another without an intermediate direct current (DC) link. It then describes the two main modes of operation for cycloconverters: blocking mode and circulating current mode. The document goes on to discuss different types of cycloconverters including matrix, single-phase-to-single-phase, and three-phase-to-three-phase cycloconverters. It concludes by listing some applications and advantages of cycloconverters, along with limitations.

1. WELCOME TO
A presentation on
CYCLOCONVERTER
 Presented By:
Md. Rezvi Hossain
Student ID: 110920
Year : 4th ; Term: I
ECE Discipline,
Khulna University

2. WHAT IS CYCLOCONVERTER?

3. DC LINK AC-AC CONVERTER:
Vdc
3-Phase
Supply
Converter Inverter
Load
3-phase
Output

4. MODES OF CYCLOCONVERTER:
Blocking Mode:
 Depends on the polarity, one
of the converters is enabled at
a time.
Circulating Current Mode:
 Both the converters operate
at all time in this case.
 An intergroup reactor (IGR) is
needed.

5. TYPES OF CYCLOCONVERTER
 Matrix cycloconverter
 Single –phase-to –single-phase cycloconverter.
 Three –phase-to-three-phase cycloconverter.
 Single-phase-to-three-phase cycloconverter.

6. MATRIX CYCLOCONVERTERS:
It consists of a matrix of 9
switches connecting the three
input phases to the three output
phases .
No two switches from the
same phase should be ON at the
same time.

7. SINGLE-PHASE TO SINGLE-PHASE CYCLOCONVERTER:
 It has the positive Centre-tap
thyristor converter connected
in anti-parallel with a
negative converter.
 The voltage and current of
either polarity can be
controlled in the load.

8. THREE-PHASE TO THREE-PHASE CYCLOCONVERTERS:
 Contains about 18 thyristors
[switches]. The circuit comprises of
three identical half-wave anti-
parallel phase groups.
 The output voltage contains
complex harmonics which may be
filtered by the machines effective
leakage inductance.

9. APPLICATIONS
 Cement mill drives
 Ship propulsion drives
 Rolling mill drives
 Ore grinding mills
 Mine winders
 Synchronous Motors
 Variable- speed, constant-
frequency{VSCF} power
generation for aircraft 400 Hz
power supplies.

10. ADVANTAGES
 No intermediate DC state is required for AC-AC conversion.
 Extremely attractive for large power, low speed drives.
 Capable of power transfer in either direction between source
and load.

11. LIMITATIONS
 Large number of thyristors are required.
 The output frequency is limited to one-third of the input frequency.

12. THANK YOU

13. QUESTIONS???