Model And Experimental Study And Characteristics Evaluation For Semiconductor Pulsed Power Devices

In the field of microsecond and sub-microsecond pulsed power technology, pulsed power semiconductor device has great advantages over the traditional pulsed gas switch, such as shorter recovery period, higher reliability, less losses and longer life. According to the principle of controllable plasma layer commutation, reversely switched dynistor(RSD), a kind of semiconductor switch, specially applied in the pulsed power area, is designed. As a result, its blocking voltage can reach as high as several k V and its current rising rate can get to hundreds of k A/?s. In addition, during the switching process, all devices can conduct simultaneously and uniformly. Meanwhile, the traditional power semiconductor devices, IGBT, and certain thyristor device, can also be used in the pulsed power system.RSD is a two-electrode device between thyristor section and transistor section, with thyristor and IGBT being representatives of current control and voltage control power semiconductor devices triggered by gate respectively. On the basis of carrier mobility, carriers generation-recombination and electro-thermal coupling effect, on the basis of typical device parameters, this thesis will construct a two-dimensional electro-thermal coupling model concerning RSD, thyristor and IGBT by means of finite difference method, Newton iteration method and Runge-Kutta method.Ensuring that the simulation blocking voltage is about 1000 V, this research aims at optimizing the researched and optimized the width and doping concentration of the RSD, thyristor and IGBT. This research also investigates the turn-on performances and thermoelectric coupling characteristics of each one at low and high current density to compare and research the turn-on and thermoelectric coupling characteristics of the three devices. The results show that the pulsed power device RSD acquires the lowest turn-on voltage and power dissipation. This advantage is more obvious under the high current density. Besides, within the same circumstance, the maximum lattice temperature of RSD is much lower than thyristor and IGBT.In accordance to the DC application FOM(Figure of merit) of IGBT and thyristor, the application environment of the combined devices put forward the FOM analytic formula of the quantized semiconductor pulse power devices. The experiment tests the simulation results of the critical triggering characteristics under different current density conditions. It also measures the switching characteristics of contrast devices under the critical triggering condition. In the end, the switching process of the three devices is researched by experiments. It gets the results of the turn-on voltage and current for single device. It also utilizes the high bandwidth and precision low voltage probe voltage division method to perfect the measuring result. The results also indicate that RSD has much lower turn-on voltage and power dissipation than thyristor and IGBT. At the same time, it figures out that the turn-on dissipation of RSD accounts for about 3.04% of the total energy stored in the capacitance. Compared with thyristor, RSD possesses better serial characteristics.