Title |
DC Voltage Balancing Control of Half-Bridge PWM Inverter for Liniear Compressor of Refrigerator |
Authors |
Ho-Jin Kim ; Hyeong-Jin Kim ; Dong-Youn Kim ; Jang-Mok Kim |
DOI |
https://doi.org/10.6113/TKPE/2017.22.3.256 |
Keywords |
Linear compressor ; Unbalanced voltage ; IP controller ; Single-phase inverter ; Half-bridge inverter |
Abstract |
This paper presents the control algorithm of a single-phase AC/DC/AC PWM converter for the linear compressor of a refrigerator. The AC/DC/AC converter consists of a full-bridge PWM converter for the control of the input power factor and a half-bridge PWM inverter for the control of the single-phase linear compressor. At the DC-link of this topology, two capacitors are connected in series. These DC-link voltages must be balanced for safe operation. Thus, a new control method of DC voltage balancing for the half-bridge PWM inverter is proposed. The balancing algorithm uses the Integral-Proportional controller and inserts the DC-offset current at the Proportional-Resonant current controller of the inverter to solve the DC-link unbalanced voltages between the two capacitors. The proposed algorithm can be easily implemented without much computation and additional hardware circuit. The usefulness of the proposed algorithm is verified through several experiments. |