Research Of High Power Constant Current Source Based On DsPIC Control

The circuit breaker as an important equipment in low-voltage electrical, often used in low voltage distribution systems, transmission systems or other electrical devices, is responsible for breaking, carrying normal or abnormal current(such as short-circuit). In the reliability test of the circuit breaker, test current quality is the key to the success of the test, so the constant current source device is essential. In the domestic low-power and stable current source products have matured, but intelligent big power and high stability constant current source products grow rapidly.To produce the power AC current source equipment used in the circuit breaker overload test, this paper focuses on working principle and control algorithms of the three-level Cuk regulator’s AC current source-based IGBT switching device, and uses Saber simulation to simulate circuit topology, then verifies the ability of the three-level regulator’s Cuk circuit. Design IGBT drive circuit design, triac trigger circuit, voltage and current acquisition circuit and zero-crossing detection circuit and communications hardware circuits, etc. Taking high-performance 16-bit dsPIC digital signal controller as core, controller controls the driving signal of the constant current source device, and achieves fuzzy PID closed-loop control through real-time acquisition of voltage and current datas. Finally, by using the Modbus fieldbus communication technology the paper achieves real-time detection of the host computer to the lower machine and human-machine interaction.