Development of high voltage DC power supplies for electrostatic precipitator

This paper describes the development of high-voltage DC power supply (HVDCPS) for electrostatic precipitator (ESP). Compared with power supplies using low frequency transformer, high frequency power supplies have advantage of reduced size and small output voltage ripple. In this paper, the HVDCPSs are designed and implemented based on LCC resonant converter operating at continuous conduction mode (CCM). LCC resonant converter can achieve high frequency operation and efficiency because of its soft switching characteristic. The high frequency operation contributes to compactness of the converter by reducing sizes of resonant tanks and transformer. And a low output voltage ripple can be also achieved. LCC resonant converter is advantageous for using a voltage multiplier and a high step-up transformer by utilizing the parasitic component of the transformer as its resonant component. In this study, two HVDCPS are designed and implemented for ESP. For safe and stable operation, protection circuits for over voltage and arc current, and auto-restart function are included. The experimental results are introduced.