Research On Controllable Pulse Power Of High Speed And Voltage

High-voltage pulse power has been applied in many fields, such as laser technology, electrical discharge machining, plating, and welding. In order to obtain high peak and narrow width laser pulse, the method of Q-Switching is used constantly. High-voltage of kV is added on the Q-switched crystal. Repid pulse is required in Q-Switching power. For the rare application and the less research, the price of the Hith-voltage power is expensive. A high-voltage pulse power supply based on MOSFET and with adjustable amplitude, frequency and duty was designed to support electro-optic Q-swtiching.After the analyzing to the charactors of the MOSFET, two kinds of driving and switching circuit were designed based on H-bridge and push-pull circuit. The trigger signal generated by FPGA with counter is adjustable. The trigger frequency ranged in 100 kHz and pulse width ranged from 200ns to 2000ns. Switching circuits based on MOSFET were cascaded to increase the amplitude of pulse. Transformer was designed to achieve electrical isolation and synchronize trigger signal.In consideration of the drive circuit requirements, some separated low-voltage powers were designed to supply the system. Models of high-voltage were applied to generate 1000V DC. The volume of the experimental system was greatly reduced.The waveforms of pulse in different condition were obtained. When the load is 1k (?), and voltage of high-voltage DC is 1000V, the pulse width can be adjustable from 500ns to2000ns, while pulse rising and falling was about 150ns. The pulse power can be adjusted to meet the design requirements of Q-switched CO₂ laser.The experimental results proved that the design of the pulse power supply is feasible. It can meet the requirement of experiment. In addition, this power supply has the advantages of simple structure and low cost.