智能交流接触器温度补偿控制策略研究

Control strategy of temperature compensation of intelligent AC contactors

环境温度及接触器频繁工作会导致线圈温度上升,对接触器吸合产生影响,针对此问题,基于带反馈控制的PWM(脉宽调整)型智能交流接触器系统结构、工作原理及其动态特性,提出一种基于智能交流接触器的温度补偿控制策略。智能控制系统采集实时的输入电压和线圈温度值作为反馈输出控制量,通过特性分析与实验建立动态控制表,根据电压与温度值查表计算输出最佳占空比及其强激磁时间的PWM波,控制接触器合闸。研究结果表明,通过此控制策略能使接触器在各工作温度及阈值电压范围内实现最优合闸,并保证在较高温度下可靠合闸,提高其工作性能、使用寿命和环境适用范围。

The dynamic response of the ac contactors can be seriously affected by the high temperature caused by the frequently switching and the environmental temperature. A control strategy is proposed to compensate the influence due to the temperature rising. The strategy is implemented with PWM principles. The real-time input voltages and temperature values are obtained by the control u- nit as the feedback signals, A lookup table is established by measuring the relationship between the control voltage, temperature and the duty cycles of the PWMs. The optimal duty cycles and the strong excitation time at different temperature are determined from the lookup table when feedback signals are obtained. Experimental results show that the closing process of the contactors can be optimized at different temperatures. The influences of the temperature rising can be compensated by using the control strategy.