Measurement of capacitor current as control variable for voltage source inverter

Several control strategies have been proposed to deal with the problems of UPS feeding nonlinear loads. To ensure stability and fast response, current components on the LC filter are often used as control variables. Theses currents can be very noisy and unacceptable to work as an stabilization schema. A procedure to deal with measurement problem is developed and shown to be effective. Both simulations and experimental results show the validity of using capacitor current as control variable.