Boost efficiency and reduce heat in your PMSM

IEEE Paper presentation at 25th COMPEL workshop - Lahore, Pakistan

Implementation and Validation of a Simplified Dead Time Compensation Scheme for a High-Power Space Vector Controlled SiC Inverter PMSM Drive

At the 25th IEEE Workshop on Control and Modelling for Power Electronics, to be held at the Lahore University of Management Sciences, our engineers will present a simplified method for dead time compensation when driving Permanent Magnet Synchronous Motors. 

Less computationally intensive, this scheme allows up to 4% reduction in Total Harmonic Distortion (THD), by suppressing voltage errors and low-order harmonics, reducing heat build-up due to eddy currents in the motor.

Abstract— Implementing dead time is mandatory to avoid shoot-throughs across the same phase leg switches of a 3-phase half-bridge voltage source inverter. However, it causes distortions in voltage and current waveforms with higher-order harmonics, resulting in torque ripples in permanent magnet synchronous (PMSM) drives. Due to higher switching speed, and sharp dV/dt

and dI/dt characteristics, this effect is further pronounced in SiC-based PMSM drives. In this paper, a detailed investigation of the deadtime effect on the output voltage and current waveforms is carried out, and subsequently, the hardware and software implementation of a simplified deadtime compensation scheme based on the current polarity detection method is presented. The implementation involves the integration of a commercially available state-of-the-art high-power SiC intelligent power module and an automotive-grade software and hardware control system to drive a PMSM. LTspice® is used for system simulations and a dyno-test bench is used for hardware verification of the deadtime compensation scheme. Results show that the scheme is simple and effective for high-power PMSM drives with considerable improvements in voltage and current waveforms along with a THD reduction of up to 4% in output phase currents for a typical operation.

Authors for CISSOID - Teddy Bonnin, Mashood Nasir, Pierre Delatte
Author for Silicon Mobility - Mostafa El Mokadem

CISSOID ingenuity facilitates faster inverter development