Digital Signal Processor Based Shunt Active Filter Controller for Customer-generated Harmonics and Reactive Power Compensation

Abstract

This article proposes a digital signal processor based simplified current controller for shunt active power filter to compensate customer-generated current harmonics and reactive power. The compensated source current contains the same level of harmonic distortion as present in the source voltage with equal I/V ratios at all frequencies. This separates the contribution of the customer non-linear load and, thereby, forces this load to behave as a linear load at a unity power factor. The current-controlled voltage source inverter used in active filter configuration is regulated to emulate the combination of load and active filters as an equivalent conductance across the source voltage. An innovative feature of the proposed controller is to achieve conduction emulation without sensing the source voltage. The proposed controller is first realized in a MATLAB/Simulink (The MathWorks, Natick, Massachusetts, USA) environment under sinusoidal and distorted supply voltages condition with varying loads. The simulated results are validated experimentally by developing a laboratory prototype using a low-cost, fixed-point eZdsp to show the effectiveness of the controller.

Keywords:

• customer-generated current harmonics
• digital signal processor
• DC-link capacitor voltage
• reactive power compensation
• shunt active power filter