Research On The Pulse Power Supply For High-power Semiconductor Laser Diode Arrays

Semiconductor laser has small volume,high efficiency,good reliability,long working life,and it has been widely used in the national defense,scientific research,medical treatment,processing,and other fields.Therefore,research on its driving power supply is important.In this paper,the research on pulse power supply of high power semiconductor laser is carried out.It is required that the pulse power supply outputs a nearly rectangular pulse current with rapid and no overshoot on the rising and falling edges.The output pulse current is smooth and stable without overshoot during pulse discharge.In this paper,the working principle and power characteristics of semiconductor lasers are analyzed,and the requirements of pulse power supply for high power semiconductor lasers are determined.A large current and a wide range of voltage are required.Therefore,the topology of multi-module cascade with the way of switch linear region control is chosen in the paper.That is to say,the topology of multi-module cascade is adopted to meet the requirement of wide range of voltage,and the switch operating in the linear state can control the pulse current to be smooth and stable without overshoot.In the pulse power supply,a combination of a pre-stage LCC charging unit and a post-stage pulse current generating unit is employed.The LCC resonant circuit has the characteristics of soft switching and resistance to load short-circuit and open-circuit,and it can realize the function of constant current charging of the storage capacitor;the latter-stage pulse current generating circuit selects a high-power MOSFET as a master control device,utilizes the drain current controllability of the saturation region of the MOSFET,and generates a pulse current through the gate voltage control.The control part adopts a combination of analog and digital control methods to make the pulse power supply control more flexible.A given integrator in the pulse current given step is add,which can effectively control the rising process of pulse current,and improve the control accuracy.The micro-current pre-start control method is proposed because of the problem of overshoot and oscillation in the pulse power supply.The main purpose of this method is to solve the nonlinear problem caused by the switching threshold voltage of MOSFET,thus eliminating the oscillation and overshoot that occurs during the rising process of pulse current.A experimental platform was built to complete the single module 14.7kW pulse discharge experiment and the multi-module 132.3kW pulse discharge experiment,and the micro-current pre-start control method was analyzed.Finally,the output performance of the semiconductor laser pulse power supply was reflected,and the feasibility and effectiveness of the micro current pre-start control method is proved by the experimental results.