A space vector modulated CSI-based AC drive for multimotor applications

A space vector controlled channel state information (CSI) drive for multimotor applications is investigated. The multimotor operation of the drive is achieved by integrating the proposed active damping control, inverter-side DC link voltage feedforward control and pulse width modulation (PWM) index control into the conventional V/f control. The main function of the active damping control is to suppress possible LC resonances caused by the inverter filter capacitor and motor inductances. This function is essential in achieving stable operation of the drive, especially in the multimotor drive where multiple LC resonant modes exist. An additional advantage provided by the active damping control is that it makes the control system less sensitive to motor parameters. The inverter-side DC link voltage feedforward control and the adjustable PWM modulation index control are developed to improve the dynamic performance of the drive system. In addition, the proposed space vector PWM pattern features a low switching frequency (500 Hz), which makes the proposed drive system suitable for high power applications. The system stability is investigated by means of eigenvalue analysis. The theoretic analysis is verified by experiments on a digital signal processing (DSP) controlled CSI multimotor drive.