Active Clamp Forward Converter Combined with Dither Voltage Generator for Poultry Stunning Applications

This paper presents an intelligent poultry stunner for improving carcass quality and animal welfare. In the stunner system, an active clamp circuit is used in a forward converter to reset the magnetizing energy and to recover leakage energy trapped in the transformer, increasing its conversion efficiency. In addition, a dither generator realized with a half-bridge inverter is adopted to fast breakdown the skin impedance of the poultry with which can reduce poultry stress and improve carcass quality during stunning interval. To simplify the circuit of the proposed stunner system, switches in the forward converter and the half-bridge inverter are integrated with the synchronous switch technique. With this approach, the proposed stunner system can achieve a higher conversion efficiency, less component counts, lighter weight and smaller size. Compared with the one without switch integration, the proposed one can raise efficiency of 5% under mil load condition. Under a fixed frequency of 400 Hz, its output voltage can vary from 60 V to 140 V and its duty ratio is from 0.3 to 0.7. Performance measurements from a prototype have verified the feasibility of the overall system design. The designed system has contributed a lot to improve animal welfare and has attracted much attention