Research On The Communication-Capable Low Voltage Switchgear Based On CAN Bus

By applying the micro-electronics, micro-controller and field bus technology into the renovation of low voltage switchgear, people can design the communication-capable low voltage switchgear. The new products can realize the intelligentization and function combination of the traditional low voltage switchgear. Also you can realize the systematization and automation for the controlling of low voltage switchgear by using of the field-bus communication technique. The new products represent one of the most important developing directions for the low voltage electrical apparatus in 21 century. In our paper, we research the domestic and abroad low voltage switchgear products and the field bus technique, then conclude the typical mode for these products and select the CAN bus as our communication method. After that we especially aim at the intelligent design based on MCU and the communication design based on CAN bus for a current relay for rapid action. By this way, we can research some typical modules of communication-capable low voltage switchgear. Then our working will do good to further research on the communication-capable low voltage switchgear based on CAN bus.The realization of traditional rapid action relay function needs the combination of electromagnetic current relay, time relay and signal relay. While our new product, the intelligent electrical apparatus with communication ability, can not only realize the time limit rapid action relay function independently but display and modify the action parameter of relay such as the current and the time. The more important character of our product is single intelligent relay can connect to the CAN bus as a node and communicate with each other digitally.Then we can realize long-distance monitoring and displaying the state of else intelligent relay nodes, set and modify their action parameters and states as well as analyze, memorize and deal with the data from low intelligent nodes. Our design will surely improve the function of relay and accord with the requirement of power system.The principle and theory of our design is discussed chiefly. What is elaborated in the paper is the hardware and software design of intelligent relay and PC monitor node.