Circular space vector modulation (CSVM) method and its performance analysis

An original circular space vector modulation (CSVM) strategy for AC motor drive control invertors is developed. The CSVM aims to bring the actual stator flux space vector trajectory nearer to the circular path of a reference flux vector, and keep a small phase error between the actual and reference flux vectors. The strategy is compared with other pulse width modulation (PWM) methods in terms of produced Joule losses and ripple torque components. The obtained results show that the CSVM method is very effective, especially in the upper range of the modulation index. The changes of the rotor resistance and leakage inductance of an induction motor (IM), which are due to the skin-effect, are taken into consideration within the analysis of CSVM method properties. The proposed CSVM is also experimentally verified