基于直流供电技术的电压暂降保护系统研究

变频器在软启动、变频调速、优化设计、经济运行等方面具有明显优势,得到广泛应用。在电压暂降期间,变频器会因低压保护而跳闸,造成连续性生产企业非计划停运,带来巨大的经济损失和事故。根据变频器交-直-交的特性,结合电力电子技术,研究开发了两种基于直流供电技术的电压暂降保护系统。两种保护系统分别利用电网残压和蓄电池组作为能量来源,通过Boost DC/DC变换器,输出恒定的直流电压,为变频器直流母线提供恒定的直流电。实验数据和现场应用表明,该两种电压暂降保护系统可以确保变频器在电压暂降期间正常运行,大大提高了供电可靠性,为用户避免了大量的经济损失。

Research on Voltage Sag Protection Based on DC Power Supply Technology

The inverter is widely used for its obvious advantages in soft start, variable frequency speed control, optimal design, economic operation and so on. During voltage sag, the inverter will be tripped because of low voltage protection, which would cause the important motor driven by inverter to stop working. This will result in non planned outage in the continuous production enterprises, leading to huge economic losses and even personal safety accidents and environment problems. According to the characteristics of inverter's AC-DC-AC structure and combining power electronics technology two kinds of voltage sag protection (VSP) systems are researched and developed based on DC power supply technology which take network residual voltage and batteries as energy source respectively. And through Boost DC/DC converter, the VSP system outputs a constant DC voltage, supporting inverter's DC bus. Experimental data and field applications show that the two kinds of VSP system can ensure the normal operation of inverter during voltage sag which greatly improves the reliability on demand side and saves a lot of economic loss for users.