低压电网具有无功补偿等功能的综合自动化装置的研究

Study on the integrated automation device for low-voltage electric network with reactive power compensation and other functions

在电力系统中,由于无功不足而给系统带来的危害已不容忽视,目前低压电网的无功补偿大多采用并联电容器方式,虽然其控制简单,但补偿精度不高,而且无功补偿和低压保护都是分别控制的。文章以单片机为控制部分的核心,具有无功补偿、保护等多种功能进行研究。电容器采用8:4:2:1的不等容分组方式,提高补偿精度的同时还可减少投切开关的数量。研究中采用的电容投切开关是集交流接触器和晶闸管二者优点于一身的机电复合开关,变压器低压侧保护用交流接触器代替断路器,利用单片机进行控制。结果提高了系统的自动化功能,同时也大大降低了系统的造价。

In electric power system, the hazard brought by reactive power deficiency must be paid attention to. Now reactive power compensation in low-voltage network mostly employs parallel capacitors, the control is single, but the compensation precision is not high, and the reactive power compensation and low-voltage protection are controlled, respectively. Single chip microcomputer was the core of the control section of the study, and the control section had several functions such as reactive compensation, protection, etc. The grouping mode of the capacitors was 8：4：2：1, it can improve the compensation precision and can lessen the switches. The switches of the study employed electromechanical combination switches which had the merits of AC contactor and thyristor, the low-voltage protection of transformer employed AC contactors instead of breakers, which were controlled by single chip microcomputer. So the automatic function of the system is improved and the cost of the system is reduced greatly at the same time.