A novel hysteresis current control switching method for torque ripple minimization in multi-phase motors

Current control techniques are a key issue in the field of motor drives and power converter system operation. Motor drives apply current to the correct windings in the proper direction at the appropriate time in a process referred to as “commutation.” Various techniques are used to regulate the winding current. Hysteresis current control is widely employed in voltage source inverters because of its dynamic response capabilities and robustness. This paper presents a novel hysteresis current regulation switching method that controls the On-Off state of switches in a system of 12 full-bridge single-phase inverters used to supply a 60kW 12-phase SPMSM (Surface Mounted Permanent Magnet Synchronous Motor). The switching methods are analyzed using an inverter simulation model with an equivalent motor load. A novel hysteresis current control switching method is proposed for the independent full-bridge single-phase system and the simulated current waveforms are compared to the experimental data which was collected from the system using a Texas Instruments TMS320F28335 DSP. The torque waveforms generated by the motor when controlled with the proposed switching method were analyzed using electromagnetic FEA (Finite Element Analysis) simulations and the results are compared to those obtained using the conventional switching method.