耐电压测试仪保持时间自适应校准装置研究

Research on the Adaptive Calibrator of Voltage Dwell Time for Withstanding Voltage Tester

对耐电压测试仪输出电压保持时间的校准技术进行了研究。分析了测试仪输出电压的波形特征,以及对保持时间校准的影响,指出准确识别输出电压的上升和下降阶段是保持时间校准的先决条件。为克服设置计时起始电压测量法的不足,提出了一种新颖的基于波形分析的保持时间自适应校准方案。通过A/D转换器对输入电压波形进行高速采样,构建电压信号的完整包络曲线;再由微控制器对包络曲线进行自动化整体分析,从而得到保持时间的校准值。测试验证结果表明,校准装置的测量准确度与被校耐电压测试仪的输出电压量值无关,具有自适应的突出优点。校准装置实现了保持时间的高准确度、高分辨力测量,完全满足校准工作的实际需要。

The calibration technology of the output voltage holding time of the withstanding voltage tester was researched.The waveform characteristics of the output voltage of the tester and its influence on the calibration of dwell time were analyzed.It was the precondition of the dwell time calibration to recognize the voltage ramp-up and ramp-down of a programmable withstanding voltage tester.In order to overcome the disadvantages of traditional method,a dwell time adaptive calibrator based on waveform analysis was proposed.The calibrator uses a A/D converter to conduct high-speed sampling of the input voltage signal,and then rebuilds the to form a complete envelope curve of the input voltage,which was then analyzed automatically by the micro-controller to obtain the calibration value of the dwell time.The results of test verified that the dwell time calibration scheme is independent of the voltage value,and features self-adaptation.The calibrator realized high accuracy and high resolution measurement of dwell time,which fully meet the practical needs of dwell time calibration.