Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco R. Griñó, R. Costa-Castelló and E. Fossas Instituto de Organización y Control (IOC) Universitat Politècnica de Catalunya Barcelona, Spain Digital Control of a Single-Phase Shunt Active Filter

34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Introduction Proliferation of nonlinear loads ->This fact has deteriorated the power quality of electrical power systems. More stringent requirements proposals IEC {2,4} and IEEE-519.

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Basic Concepts Linear Load Nonlinear Load Active Filter

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Complete Picture Full Bridge Boost Converter

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Boost Converter r L C r L C

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Boost Converter II The averaged model

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Control Goals Constant average value of the voltage at the DC bus capacitor: Current in phase with the voltage waveform:

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Proposed Control Scheme Two control loops : –Current loop : Digital Repetitive Control –Voltage loop : Classical PI Control Boost Converter Repetitive Controller PI Controller

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Current Control loop ZOH, T

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Repetitive Control Basics +

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Repetitive Control Scheme Repetitive Controller

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Repetitive Stability Conditions 1.First stability Condition : The System without the Repetitive Controller must be stable. 2.Second stability Condition 3.Third stability Condition :

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Voltage Loop Current loop in steady state r=0

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Voltage Loop PI

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Setup : General view

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Setup : IGBT drivers

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Setup : Control hardware

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Setup Active filter parameters: –Capacitor: 6600 uF, 450 V DC –Inductor: 0.8 mH –parasitic resistance: 0.04 Ohm –IGBT: 1200 V, 100 A Feedback paths (sensors): –Network voltage: voltage transformer (220V/15V) –Network current: Hall-effect sensor (TECSA-HA ) (50A) –DC bus voltage: AD-215BY isolation amplifier Control hardware: –ADSP floating-point DSP –ADMC-200 coprocessor: A/D channels and PWM generation

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: Nonlinear Load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: No-Load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: Full NL load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: Full NL load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: Full load to No-load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Experimental Results: No-load to full load

Digital Control of a Single-Phase Shunt Active Filter 34th IEEE Power Electronics Specialists Conference June 15-19, Acapulco Conclusions The paper shows the design of an all digital multirate controller for a single-phase parallel active filter. The inner current control loop is designed using a repetitive control approach that. The outer slow sampling rate voltage control loop presents a good dynamic behavior in front of sudden changes of the load.