{DC-bus voltage control of three-phase AC/DC PWM converters using feedback linearization}

Title{DC-bus voltage control of three-phase AC/DC PWM converters using feedback linearization}
Publication TypeMiscellaneous
Year of Publication2000
AuthorsLee D-C, Lee G-M, Lee K-D
ISBN Number0093-9994 VO - 36
Keywords1.5 kVA, AC input currents, AC-DC power convertors, Analog-digital conversion, capacitor current, Capacitors, Control systems, DC electrolytic capacitor size reduction, DC output voltage, DC-bus voltage control, Electric variables control, fast voltage control, fast voltage control strategy, feedback linearization, input current regulation, input-output feedback linearization, insulated gate bipolar transistor, Insulated gate bipolar transistors, integrators, linearisation techniques, Linearization techniques, Modeling, nonlinear model, output voltage responses, pole assignment, pole placement, power balance, power factor, Pulse width modulation, Pulse width modulation converters, PWM power convertors, Robust control, size reduction, source power factor control, State feedback, state feedback control law, system modeling, three-phase AC/DC PWM converters, unity power factor, Voltage control
AbstractIn this paper, a fast voltage control strategy of three-phase AC/DC pulsewidth modulation (PWM) converters applying a feedback linearization technique is proposed. First, incorporating the power balance of the input and output sides in system modeling, a nonlinear model of the PWM converter is derived with state variables such as AC input currents and DC output voltage. Then, by input-output feedback linearization, the system is linearized and a state feedback control law is obtained by pole placement. With this control scheme, output voltage responses become faster than those in a conventional cascade control structure. For robust control to parameter variations, integrators are added to the exact feedback control law. Since the fast voltage control is feasible for load changes, it is shown that the DC electrolytic capacitor size can be reduced. In addition, the capacitor current is analyzed for size reduction of the capacitor. As is usual with PWM converters, the input current is regulated to be sinusoidal and the source power factor can be controlled at unity. The experimental results are provided to verify the validity of the proposed control algorithm for a 1.5 kVA insulated gate bipolar transistor PWM converter system