Development Of Mechanical Characteristic Tester For Circuit Breaker Based On Embedded System

The high voltage is equipment which is used for connecting or cutting off the circuit in the high-voltage lines of power system, it plays the role of controlling and protecting the various kinds of electrical equipment in the whole electrical system. High-quality high voltage can provides reliable guarantee for safety and high effect run of electrical system. And the mechanical characteristic of a high voltage is the first to show stability and reliability during the action of voltage. So the result of tests on the associated parameters of mechanical characteristic is the most direct reflection of a high voltage. Based on the analysis of a large number of professional books and the practical situation, an embedded high-voltage circuit breaker mechanical characteristic tester was designed in this paper.The design of this tester mainly included software and hardware. According to circuit functions, the design of hardware circuit was divided into three sections, which were the core circuit, the interface circuit of the signal collection and output, and the peripheral circuits. The core circuit adopted S3C2440A for the minimum system board of the core processor. The interface circuit included the A/D transform circuit, the D/A output circuit, the network card circuit, LCD display interface circuit and power supply circuit. The peripheral circuits included the analog signal conditioning circuit, the digital signal gathering circuit and output control circuit. Modularity and functional design concepts and multi-channel design method were adopted in the circuit design, which reduced the difficulty of system design. Due to the phenomenon of the higher voltage and the strong field in the actual application situation, the isolation circuitry was used in multiple places in the circuit design, it also made disturbances were reduced which were caused by the pre-stage circuit and great improved circuit reliability.In this paper, the software design adopted mini type embedded operating system μC/OS-Ⅱ as software application platform. According to the modularity and reentrant design principles, the software of whole system was divided into six application tasks. And the network traffic control task used for communicating between the PC and microchip, the display task used for outputting and showing by LCD, the measure and compute task used for testing mechanical characteristic, the information input task used for inputting the parameters and sending control codes by users, the storage task used for storing the user settings result and test results of the voltage, and the printing task used for printing the test results. Above all tasks implemented task scheduling and resource distributing under μC/OS-II operating systems, the six tasks operated coordinately and realized test function of the whole system.The common VS1outdoors vacuum breaker was used for experiments in this system, according to the repeated experiments, the results showed that this test system reached the design goal, so it can be the special test equipment for testing mechanical characteristic of high voltage.