Low Order Current Harmonic Compensated LCL Filter Based High-Performance PMSM Drive for High Speed Applications

High-speed permanent magnet synchronous motor (PMSM) drives are popular for high power density and efficiency. Generally, these motor drives have fundamental frequency
$(f_{1})$
ranging up to a few kHz. Thus, the switching frequency
$(f_{sw})$
of motor drive is desired to be high
$(\geqslant 20\ \mathbf{kHz})$
for attaining reasonable performance. Due to the limited availability of SiC devices for moderate power levels
$(\geqslant 50\ \mathbf{kW})$
, Si IGBT-based converters are preferred.
$f_{sw}$
is restricted to 8 kHz for such converters because of constraints on switching energy losses. This paper deals with the design of a high-performance motor drive for a three-phase high-speed PMSM rated at 50 kW and 916 Hz (5500 rpm). Typically, an asynchronous sine-triangle (AST) pulse width modulation (PWM) technique with
$f_{sw}= 8000$
Hz is deployed in these drives which results into poor thermal performance. Deploying synchronous sine-triangle (SST) PWM improves thermal performance but deteriorates total harmonic distortion in line current (i.e
$I_{TND})$
and peak-peak torque ripple
$(\tilde{\tau})$
. This paper proposes LCL filter-based PMSM drive with active damping to improve the performance of PMSM drive over low
$(f_{1}\ \leq\ 500\ \mathbf{Hz})$
and high
$(f_{1}\ \geq\ 700\ \mathbf{Hz})$
ranges of speed. Further, low order current harmonic compensation (LHC) is proposed and incorporated in LCL filter based drive to improve the performance over complete range of speed. MATLAB/Simulink based simulation results are presented for the proposed PMSM drive.