Performance improvement speed control of IPMSM drive based on nonlinear current control


Abstract: Recently model predictive control (MPC) scheme emerges as an efficient current control technique for dynamic performance of motor drives. For excellent dynamic performance, maximum torque per ampere (MTPA) control technique is utilized to achieve maximum torque while using minimum current constrain in contrast to conventional qaxis current control. Model predictive current control (MPCC) scheme alongside MTPA control is employed to replace the traditional constant gain proportional-integral (PI) current control and a nonlinear hysteresis current (HC) control schemes. The PI and hysteresis current controller offers satisfactory performance at ideal conditions but, with variable speed and load conditions, these control schemes cause high current harmonics, high torque ripples, and reduces the speed tracking performance. Therefore, MPCC is proposed to increase the performance of motor drive and reduces the current harmonics and torque ripple at varying load conditions. The proposed design is modeled in Matlab (MathWorks, Inc., Natick, MA, USA), and the results are compared with the traditional speed control schemes to verify the effectiveness. The simulation result shows that the MPCC for IPMSM offers high dynamic performance with reduced steady-state error under variable load conditions compared to conventional control scheme. With MPCC, the overall performance of IPMSM is improved and show robustness.

Keywords: Interior permanent magnet synchronous motors, maximum torque per ampere, nonlinear control, speed control, torque response, stability analysis

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