Abstract: A mixed signal controller for a power quality compensator includes an analog circuit, an analog-to-digital converter (ADC), and a digital circuit. The analog circuit amplifies an input signal from the power quality compensator by a gain factor and outputs an analog signal, which is converted to a digital signal by the ADC. The digital circuit receives the digital signal, calculates the reference compensating current of each phase and then generates a trigger signal via hysteresis PWM to the power quality compensator. The digital circuit includes an evaluation circuit that calculates a value of the system total harmonic distortion after the power quality compensator compensates power and adjusts the gain factor when the value of the system total harmonic distortion reaches a predetermined threshold.

Abstract: A mixed signal controller for a power quality compensator includes an analog circuit, an analog-to-digital converter (ADC), and a digital circuit. The analog circuit amplifies an input signal from the power quality compensator by a gain factor and outputs an analog signal, which is converted to a digital signal by the ADC. The digital circuit receives the digital signal, calculates the reference compensating current of each phase and then generates a trigger signal via hysteresis PWM to the power quality compensator. The digital circuit includes an evaluation circuit that calculates a value of the system total harmonic distortion after the power quality compensator compensates power and adjusts the gain factor when the value of the system total harmonic distortion reaches a predetermined threshold.

Abstract: An adaptive dc-link voltage controlled LC coupling hybrid active power filter (LC-HAPF) for reactive power compensation includes: two dc capacitors to provide dc-link voltage; a three-phase voltage source inverter to convert dc-link voltage into compensating voltages; three coupling LC circuits to convert compensating voltages into currents; and an adaptive dc voltage controller with reactive power compensation control algorithm. The control algorithm includes: first, calculating required minimum dc-link voltage in each phase with respect to loading reactive power; three-phase required minimum dc-link voltage will be maximum one among their minimum values; compare it with predetermined voltage levels to determine final reference dc-link voltage. A dc-link voltage feedback P/PI controller outputs dc voltage reference compensating currents. An instantaneous power compensation controller outputs reactive reference compensating currents. The final reference compensating currents will be sum of them.

Abstract: An adaptive dc-link voltage controlled LC coupling hybrid active power filter (LC-HAPF) for reactive power compensation includes: two dc capacitors to provide dc-link voltage; a three-phase voltage source inverter to convert dc-link voltage into compensating voltages; three coupling LC circuits to convert compensating voltages into currents; and an adaptive dc voltage controller with reactive power compensation control algorithm. The control algorithm includes: first, calculating required minimum dc-link voltage in each phase with respect to loading reactive power; three-phase required minimum dc-link voltage will be maximum one among their minimum values; compare it with predetermined voltage levels to determine final reference dc-link voltage. A dc-link voltage feedback P/PI controller outputs dc voltage reference compensating currents. An instantaneous power compensation controller outputs reactive reference compensating currents. The final reference compensating currents will be sum of them.