电气工程及其自动化专业英语第三章翻译

电气工程及其自动化专业英语第三章翻译内容摘要：

实际的开关装置限制了电压变换率和电流变化率。 非突 变引起了开关装置的功率损耗。 我们测试开关损耗时分两种情况：感性负载和容性负载。 Switching with Inductive Load 接感性负载的开关 ： The indutor is assumed to be large so that the current through it in steady state is nearly constant that initially the switch is inductor current is +Io and freewheels through diode the switch is turned on,the current through the switch begins to build up linearly(an assumption)to+Io while the diode V1 is still on diode has zero voltage across it(an ideal diode),hence,the voltage on the switch is held constant at+ the current buildup is over,the diode V1 ceases to conduct and the voltage on the switch ramps linearly(again an assumption)down to zero. 假设电感无穷大，即在稳定时流经电感的电流是恒定的 Io，假定开始时开关处于关断状态。 电感电流为 +Io 惯性流过二极管 V1。 当开关闭合后，电流流经开关开始建立线性上升 +Io 此时二极管扔导通。 二极管压降为 0，此时开关两端电压维持在 +Us 当电流建立完成后，二极管 V1 截止，开关两端电压线性下降为 0。 When the switch is turned off ,the voltage begins to build up linearly to +us while the diode V1 is off. while the diode is off the current through the switch equals the inductor current,which is constant I0 After the switch voltage reaches aero, the current through the switch begins to decrease below I0,as the remaining current is now steered through the diode V1 which has now turned on The current through。