Influence of filter parameters/topologies on stability of matrix converter-fed permanent magnet brushless motor drive systems

This paper analyses the stability of matrix converter-fed permanent-magnet brushless AC motor drive systems. The dynamic interaction between the input filter and the motor drive system are fully represented and the characteristics of the matrix converter are derived based on the commonly adopted modulation strategies by neglecting the effect of switching harmonics and taking average voltage and current over a switching period. The state-space equations governing the dynamics of the complete system can be established based on the input filter and motor drive sub-system together with the characteristics of the matrix converter. The stability of the system is analyzed by evaluating the eigenvalues of the Jacobian matrix of the system state-space equations. The influence of filter topologies and modulation strategy on the drive system stability is quantified. It is shown that filter parameters/topologies, the drive control bandwidth and its direction of power flows have a significant influence on the system stability. Time domain simulations have validated the results of eigenvalue analysis.