闪变测试系统研究

Study on voltage flicker measurement systems

闪变作为评定电能质量的重要指标 ,能更直接、更迅速地反映出电网的供电质量。讨论了基于IEC设计规范的闪变测试系统设计 ,依据IEC闪变仪设计原理 ,根据自动控制理论将电压波动与闪变视感度的关系加以概括 ,建立灯—眼—脑环节的数学摸型。经过灯—眼—脑模拟环节后的瞬时闪变值 ,经过统计处理后 ,得到闪变的评价指标—短时闪变严重度pst及长时间闪变值plt。设计了一套闪变测试系统 ,软件基于LabWindows/CVI虚拟仪器开发平台 ,重点讨论了测试原理、数字化设计及软件结构。通过实际测量表明该系统性能良好。

As an important index to assess the energy quality, voltage flicker reflects the power supply quality more directly and quickly. The design of voltage flicker measurement system is studied based on IEC specifications. According to its design principles, the light eyes brain model is established by integrating the voltage fluctuation and visual sense with automatic control theory. Then the evaluation indices of short term flicker severity p st and long term flicker severity p lt are obtained by statistically processing the instantaneous flicker values after light eyes brain simulation. A voltage flicker measurement system is designed and its software is based on virtual instrument development platform of LabWindows/CVI. The measuring principles, digital design and software structure are emphatically discussed. The real measurements prove that the system performance is excellent.