换路后两个连接电容电场能量变化分析

Analysis of Electrostatic Energy Transformation in Two Connection Capacitances after Switching

在"电路理论"课程暂态分析中,换路后两个电容直接并联,或两个电感直接串联,电容电压和电感电流不再服从换路定律,当电荷与磁链重新分配后满足电荷、磁链守恒,但静电场能量与磁场能量均有损失,看似系统能量不守恒。本文将从串联暂态电量、串联稳态电压整体、并联稳态电压分体和功率密度等角度分析了能量变化,最终从线损耗和电磁辐射两方面解释了静电能的损失。

During transient state analysis of Circuit Theory course,after switching if two capacitances are in parallel or two inductances are in series,neither the capacitor voltage nor the inductance current will obey the switching law.Capacitive charge conservation and magnetism chain conservation still stand after redistribution,however,both the electrostatic energy and magnetic energy have losses which seems the system is non-conservation.This paper mainly concentrates on the energy analysis of the circuit which has only two capacitances after switching from the point of view of series transient signal,whole series steady-state voltage,individual parallel steady-state voltage and power density and then analyze the loss of the electrostatic energy in terms of line losses and electromagnetic radiation.