基于MOS控制晶闸管的高压电容放电特性

摘要

为了研究国产金属氧化物半导体（MOS）控制晶闸管（Metal?Oxide?Semiconductor controlled thyristor, MCT）与高压陶瓷电容组成的电容放电单元（Capacitor Discharge Unit, CDU）的放电特性，设计制备出体积为40 mm（L）×25 mm（W）×8 mm（H）的CDU，其回路电感约10 nH，电阻约100 mΩ。首先分析了CDU回路的R?L?C零输入响应方程，采用CDU负载短路放电实验进行验证，研究发现随着电容值的增大，CDU的峰值电流、峰值电流上升时间、高压电容的放电时间等关键参数均增大；随着放电电压的升高，峰值电流增大，峰值电流上升时间不变。采用微型爆炸箔芯片（Cu桥箔35 mΩ）和硼/硝酸钾（Boron?Potassium Nitrate, BPN）点火药（硼粉/1.50 μm，压药密度/1.57 g·cm-3）验证了CDU的作用效能，在0.36 μF/1.20 kV下，测得回路峰值电流2.032 kA，桥箔两端电压0.9273 kV，峰值电流、电压延迟时间32.4 ns，爆发点时刻168.2 ns，爆发点功率1.490 MW，且CDU能可靠进行BPN的飞片冲击点火。结果表明，基于国产MCT和高压陶瓷电容的CDU基本适用于爆炸箔起爆器等脉冲大电流激发火工品，但其综合性能仍需改进。%A capacitor discharge unit (CDU), consisting of domestic Metal?Oxide?Semiconductor（MOS） controlled thyristor (MCT) and high?voltage ceramic capacitor, was designed and prepared in order to study the discharge characteristics of CDU. The volume of the CDU is 40 mm(L)×25 mm (W)×8 mm(H). The CDU circuit inductance is about 10 nH, and the resistance is about 100 mΩ. The R?L?C zero input response equation of CDU circuit was analyzed, and was verified by the experiment of short?circuit discharge of CDU load. It is found that the key parameters of CDU, such as the peak current, rise time of peak current and discharge time of high?voltage capacitor all increase with the increase in capacitance value; the peak current increases with the increase of discharge voltage, and the peak current rise time remains constant. The function efficiency of CDU was verified by micro?chip exploding foil initiator(Cu bridge foil 35 mΩ) and boron?potassium nitrate pellet(B/1.50 μm, pressing density/1.57 g·cm-3), under the condition of 0.36 μF/1.20 kV, the measured peak current of circuit is 2.032 kA, the voltage at both ends of the bridge foil is 0.9273 kV, the delay time between peak current and voltage is 32.4 ns, the burst time is 168.2 ns, and the burst point power is 1.490 MW, and the CDU can reliably ignite BPN pellet by flyer impact. Results show that the CDU based on the domestic MCT and high voltage ceramic capacitors is basically suitable for high?current pulsed initiating devices such as exploding foil initiator, but its comprehensive performance still needs to be improved.