Voltage Controlled Shunt Active Power Filter with Grid Impedance Estimation

Inhalt:
Active power filters are used for the compensation of distortion power. For this, the grid current or the load current is measured, by what sensors have to be installed. This is causing additional costs and sources of errors regarding the correct wiring. By determining the grid impedance, the distortion current can be estimated using the voltage at the point of common coupling, which is measured anyway for the control of the APF. This paper presents a possible method for determining the grid impedance and the integration in the control loop.