The polarity of impulse voltage and the polarity of insulator surface electric charge can affect the corona initial time of insulator, the change time - interval and the corona current.
Interval: This type lets you search for two successive edges of the same polarity that are separated by a specified interval of time.
间隔触发：这种类型让你去搜寻两个相同极性、被一指定时间间隔分离的连续边界。
3
The parameters such as frequency, width of each pulse and the interval between successive pulses with inverse polarity can be changed easily in program.