Improved voltage regulation for current source inverters

Voltage regulation schemes for current source inverters commonly use a simple PI stationary frame controller but this approach is known to suffer from significant steady state error. In contrast, the more advanced schemes that are routinely used for current regulation of voltage source inverters avoid these problems. This paper presents an approach to directly utilise VSI current regulation strategies to control the voltage for a CSI, without requiring significant modification or development. The approach uses a space vector mapping technique to convert VSI modulation signals to CSI gate drive signals, which allows VSI closed loop current control strategies to be directly applied to CSI voltage regulation. Three new voltage regulation CSI controllers based on hysteresis, synchronous frame PI and stationary frame P+resonant control principles are presented based on this concept