低压交流电弧电流零区电压波形特征分析与应用

Characteristic Analysis and Application Research of Low Voltage AC Arc Voltage Waveform at the Current Zero

交流电弧的电压和电流波形包含丰富的电弧特征信息。电弧是否熄灭取决于电流过零后的极短时间内介质恢复强度与电压恢复强度的竞争,电流零区的电压波形可能含有反映燃弧趋势特征的有用信息。该文对交流电弧电流零区的电压波形进行分析,利用小波能量谱变换研究不同条件下电压波形的特征及其与电弧燃弧趋势的联系。研究结果表明,电流零区电弧电压的高尺度小波能量谱特征值与电弧燃弧趋势存在相关性。以第四尺度小波能量谱特征值作为反馈控制判据,提出智能交流接触器自适应分断控制策略,并设计控制样机进行实验验证,为交流电弧特征分析和低压开关智能控制研究提供了一种新的思路。

The voltage and current waveforms of the AC arc contain rich arc characteristic information.In a very short time after the arc current zero-crossing,the competition between dielectric recovery strength and voltage recovery strength determines the arc state.Voltage waveform at the current zero can reflect the characteristics of AC arcing trend to some extent.Based on the wavelet energy spectrum,this paper studies the relation between the voltage waveform characteristics and arcing trend under different conditions.Simulation and experimental results show that the high-scale wavelet energy spectrum eigenvalue of the arc voltage is related to the arcing trend in the current zero.Using the fourth-scale wavelet energy spectrum eigenvalue as the arc re-striking criterion,an adaptive breaking control strategy for intelligent AC contactor is proposed.Hardware control modules are adopted to verify the effectiveness of proposed strategy,which provides a way for AC arc characteristic analysis and low-voltage switch intelligent control.