The document discusses the characteristics and advantages of interior permanent magnet motors (IPM) and sensorless vector control for permanent magnet synchronous motors (PMSM). It outlines the benefits of self-sensing technology and various mathematical models to enhance performance and efficiency, including improvements for low-speed operation and position control. Additionally, it highlights the expertise of ControlTrix in implementing advanced algorithms and hardware solutions for optimized motor drive applications.

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IPM motor drive

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What is IPM?
• Interior permanent magnet motor
• Magnets are buried inside the rotor
• Permanent magnet synchronous motor
and switched reluctance motor together
• Reduces magnet size (rare earth
/expensive)
• Some portion comes from reluctance
torque

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• Inductance varies with rotor position
• Allows self sensing (encoder less)
• Gets efficiency comparable to PMSM at much lower cost
What is IPM?.
Fig: Interior permanent
magnet motor

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Sensor less Vector control of PMSM
• Required for best efficiency (meeting green norms etc)
• Complex math/DSP operations
• Only velocity control is possible
• Rotor position is required for vector control
• Sliding mode controller (SMC) estimates position (in absence of
encoder)

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Sensor less Vector drive system diagram

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• Low speed operation is not possible
• Field weakening allows operation beyond rated speed
• Field trading torque limit for speed
• Systematic analytical field weakening algorithms still required
Sensor less Vector control of PMSM.

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Sensor less Vector control of PMSM control
block diagram

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SL Vector Control of IPM (Mods.)
• More mathematically involved (trigonometric functions)
• Id and Iq references need to optimally generated
• Field weakening
• SMC may be modified for IPM but there are 2 more options

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SL Vector Control of IPM (Mods.).
Option 1.
Better performance :
• Gopinath observer
• Lower speed (than SMC) performance is possible
• Smoother operation
• Calculable gains without trial and error

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SL Vector Control of IPM (Mods.)..
Option 2.
Best performance :
• Self sensing technology
(using inductance variation dependence of position )
to sense rotor position + Kalman filtering
• Fixed point MIPS optimization required
• Near zero speed operation possible
• Position control is possible
• Nearly comparable to encoder based vector control servo drive

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Summary
• Demonstrably Better performance
(efficiency, low speed performance, position control, system cost
and DSP capability demonstration)
• Next generation motor drives (compressors, air conditioning,
refrigeration)

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How our expertise can help
• Proprietary algorithms allow 16 bit fixed point MIPs
optimized implementation of self sensing + Kalman filter
• Simulation and analysis
• Implementation on MCHV board or other custom hardware
• Performance Testing (test case generation and result analysis)
• Hardware design consulting
• Research and development

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How our expertise can help
• Guaranteed Best possible performance and support
• Competitive prices
• Proto development using 3rd party EMS/EDS

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Thank You
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