The design of a DSP-based PFN trigger timing control system and the experimental study

At the present, most of the electromagnetic gun in the research use multilevel capacitance energy storage power as incentive. The electromagnetic gun uses the PFN discharge network to form the expected discharge waveform and reach the purpose of controlling the emitting muzzle velocity of the electromagnetic gun. So it´s important to control all the power modules discharge timing precisely before the launch. This paper puts forward a trigger timing control system based on TMS320F2812. The main circuit includes four parts which are timing controlling, pulse generation, high voltage trigger and energy free-wheeling. In the circuit, the anti-interference measures have been taken. The system can output multiple control pulse signal and the delay time of the pulse signals can be changed through the computer directly. In the paper, the hardware design method and the software implementation of the DSP control system are given out. The control circuit with the TVS, spark switch and SCR as the switches is presented and the best switch is chosen by comparison. The feasibility and reliability of the system are verified through the experiment. The paper also gives the PFN discharge current figures under the simulation and experiment with different discharge timings. The optimal PFN discharge timing is drawn when the discharge waveform is suitable. In the end, it analyzes the influence of the high voltage pulse on the crowbar diode during the discharge process with different discharge timings and different positions of the switch.