零输入响应初始条件的处理  

Processing the Initial Condition of Zero-input-response

作　　者：张小虹[1] 王丽娟[1] 

机构地区：[1]解放军理工大学

出　　处：《电气电子教学学报》2008年第1期33-35,70,共4页Journal of Electrical and Electronic Education

摘　　要：经典"信号与系统"教科书中,在时域部分为了强调零输入响应是由换路前0-瞬间系统储能产生的,大都将初始条件给定为y(k)(0-),并表明因为激励为零时,系统的状态不会发生变化,所以有y(k)(0-)=y(k)(0+)。因此可用y(k)(0-)直接求解零输入响应。在不涉及具体电路问题时,上述方法简洁明了。本文举例说明在激励为零时,求解具体电路零输入响应时,会有y(k)(0-)≠y(k)(0+),从而导致双解情况的出现。为此笔者建议将y(k)(0-)改为y(k)(0+),既可使求解具有物理意义或工程背景问题与一般数学问题一致,又有利于学生掌握零输入响应求解方法。In the part of time zone in classical Signal and System textbooks,in order to emphasize that zero-input-response is caused by stored energy of 0-before switching,y（k）（0-） is intended to be initial condition.Because of the excitation being zero,the system state can not be changed,so y（k）（0-）=y（k）（0＋） and y（k）（0-） can be directly used to solve the zero-input-response.This method is concise if not be used in specific circuit.This article cites examples to indicate that y（k）（0-）≠y（k）（0＋） when solving the zero-input-response in specific circuit at the time that the excitation being zero,which leads to two results.Changing y（k）（0-） to y（k）（0＋） will make the result have sense of physics or unify the question of engineering back-ground and general question of mathematics,and also make the students master the method of solving zero-input-response.

关 键 词：y(k)(0-) y(k)(0+) 零输入响应 初始条件 

分 类 号：TN911.7[电子电信—通信与信息系统]