| With the rising achievements of modern electric power industry, the development of power facilities trends to intelligence gradually. Extend to the field of high-voltage switch, it is required that it can be applied to higher voltage levels, as well as ensure higher level of automation and reliability. Currently, with excellent arc-quenching capacity、low degree of environmental pollution and other advantages, the vacuum switch, which is gradually replacing SF6 switch, becomes a hot topic. However, the saturation effects between gap length and breakdown voltage limit vacuum circuit breakers’development at higher voltage level. Therefore, multi-break vacuum circuit breaker technology, which is composed by multiple vacuum interrupters in series, has been widely researched and applied. The paper places 126kV double-break vacuum circuit breaker for the main object of study, making research and design of the control system for the double fracture.It is concluded that the synchronization action of double vacuum interrupters is the key issue to the breaking feature of double-break vacuum circuit breakers, according to the static and dynamic characteristics, as well as the voltage distribution problem of double fracture. This not only requires the excellent action stability of each institution, but also to ensure the synchronization action between the two institutions of double-breaker. Thus, it is proposed that the objective of the control system is to ensure the same energizing and operation time, and the trajectory fits the target curve as much as possible, on the basis of maintaining the real-time synchronization of double-breaker, in order to ensure the excellent operating characteristics of the overall system.The permanent magnetic actuator(PMA) with the advantage of low moving dispersion、 high reliability and ease of handling, which can make a good match with the vacuum switch, is undoubtedly the best choice for the actuator of the double-breaker vacuum. The paper analyzes the operating principle and dynamic model of PMA, includes the different feathers of the discharge-coil-energizing stage and the iron-core moving stage through simulation analysis, and proposes the control strategy that making coordinate control of the energizing current and movement parameter of the two institutions on the basis of single institution’s own speed regulation, in order to achieve the requirements of the control objectives. The closed-loop control of single institution mainly change the opening time of IGBT by adjusting the PWM, so as to change the size of the coil current and the driving force, realizing the adjustment of motion speed. The coordinate control of two institutions mainly base on the fuzzy control, combining the advantages of the PID control. And the implementation and application of the algorithm are described in this paper. This paper uses AVR to design the intelligent control system of 126kV double-break vacuum circuit breakers. According to the results of experiments, the intelligent control system can make the original operating time of single institution 61.2ms-73.8ms improve to 67.8ms-68.2ms under different environmental conditions. In addition, the results of double fractures’synchronicity tests show that the closing time dispersion of double fracture is only 0.6 ms, as well as an excellent movement synchronization degree.The electromagnetic compatibility (EMC) is another key problem of control systems that need to consider. This article makes the EMC design mainly from the power supply port, communication port, the switch input and output port of the control system. Finally, the paper conducts the EMC immunity test from four aspects combining with the national standard requirements, such as attenuation oscillation, electrical transient bursts, lightning surge and electrostatic discharge, verifies the perturbation resistance of control system. |
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