基于永磁机构动态特性的真空断路器控制策略研究

发布时间：2018-01-13 23:30

本文关键词：基于永磁机构动态特性的真空断路器控制策略研究　出处：《北京交通大学》2014年博士论文　论文类型：学位论文

【摘要】：断路器分合闸时,电网的电流或者电压的相位并不确定,容易在分合闸过程中产生涌流及过电压,对电力系统产生较大的冲击。同步关合技术的出现,为缩短甚至避免出现断路器分合闸暂态过程提供了良好的解决方案。本文分析了同步关合的重要性及其实现机制,明确了断路器分合闸时间分散性是制约同步关合技术实现的主要难点。永磁真空断路器以其结构简单、零部件少、动作分散性小、可靠性高、寿命长等优点,成为实现同步关合的理想元件。然而永磁真空断路器受温度、控制电压、老化等因素的影响,分合闸时间仍会表现出较大的分散性,为减小分合闸时间分散性,同时减少操作能耗,优化真空断路器动触头的运动特性,提出了适用于一般永磁真空断路器的控制策略,主要完成了以下工作：对电容激励模式下永磁真空断路器的动态方程进行了分析,并以此为基础提出了基于电流源激励模式的动态方程。为分析电流源激励模式与电容激励模式的区别,建立了Ansoft仿真模型,对两种模式下,机构的动态特性进行了分析对比。由于在电流源激励模式下,真空断路器的分合闸时间不受电容容量和控制电压的影响,从而更有利于保持分合闸时间的稳定性。为实现基于线圈电流闭环的控制方式,文中详细分析了滞环控制方法的实现原理,针对方法的不足之处,对其进行了改进,提出了基于线性插值PID模式的滞环控制策略。分析了线性插值PID控制方式与经典PID控制的异同,并利用基于线性插值PID的滞环控制方法实现了对线圈电流的跟踪控制,为分合闸时,实现稳定、高效的电流源提供了基础。通过对合闸时线圈电流的分析,提出了获取较优动态特性曲线的方法,并通过利用改进的PID滞环控制方法,实现了对断路器分合闸特性的控制,将开关分合闸时间分散性控制在±0.3ms以内。为实现对永磁机构合闸时动态特性的优化,提出了变电压变输出能量(VVVE)的断路器合闸控制方法。分析了开环状态下永磁机构合闸过程的线圈电流,采用曲线拟合方式给出了合闸过程的电流方程,并对拟合方程中各项参数求解方法进行了详细的说明,给出了相应的实例证明了拟合方法的准确性。在此基础上提出了VVVE的调节方法,通过VV调节实现合闸时间的粗调,在提高合闸平均速度的同时,限制了动触头的刚合速度,通过VE调节实现了对合闸时间的微调,以及对刚合速度的控制。由于提高开关合闸平均速度与减小合闸碰撞能量一直是断路器关合过程的一个矛盾,VVVE控制方案的提出为减小上述矛盾的影响提供了很好的解决方法。为实现同步关合,文中设计了相应的永磁真空断路器控制器,对控制器的主要硬件构成进行了说明。结合同步关合的关键技术实现,说明了VWE在同步关合控制过程中所表现出的优异性能。虽然WVE是在12kV单稳态真空断路器实验基础上所获得的结论,但是本文通过所设计的控制器,成功将WVE控制策略用于40.5kV单稳态永磁真空断路器的控制实验中,从而说明了VVVE控制策略具有一般性。文中对40.5kV单稳态真空断路器在高低温下的合闸时间分散性进行了分析,并在此基础上,研究了如何通过控制策略实现断路器合闸时间的温度补偿,并给出针对40.5kV单稳态真空断路器的补偿方程。
[Abstract]:Circuit breaker closing phase, grid current or voltage is not determined, prone to inrush current and over-voltage in the opening and closing process, have a greater impact on the power system. The synchronous closing technology, to avoid even shorten the switching transient process provides a good solution. This paper analyzes the circuit breaker synchronous closing the importance and implementation mechanism, a clear circuit breaker closing time scatter is restricting the synchronous closing technology to realize the main difficulties. Permanent magnetic vacuum circuit breaker with its simple structure, less parts, the operation is stable and high reliability, long life and other advantages, has become the ideal element of the synchronous closing. However, permanent magnet vacuum circuit breaker temperature, control voltage, aging and other factors, opening and closing time will still show a large dispersion, in order to reduce the switching time dispersion, can reduce the operation at the same time To optimize the motion characteristics of the dynamic contact of the vacuum circuit breaker, the control strategy suitable for the general permanent magnet vacuum circuit breaker was put forward, and the following work was completed.
The dynamic equation of permanent magnet vacuum circuit breaker capacitor excitation mode are analyzed, and puts forward the incentive model based on dynamic equation of current source. For the difference analysis of the current source model of incentive and incentive mode of capacitor, Ansoft simulation model of two kinds of mode, the dynamic characteristics of mechanism was carried out. Comparative analysis. Due to the current source excitation mode, the closing time of the vacuum circuit breaker is not affected by the capacitance and voltage control, and thus more conducive to maintain the stability of switching time.
In order to realize the control coil current loop based on the detailed analysis of hysteresis control method and the realization of the principle, in view of the shortcomings of the method and its improvement, proposed the linear interpolation mode of PID hysteresis control strategy based on PID analysis. The linear interpolation control method with classical PID control and the similarities and differences. Control method of using linear interpolation PID hysteresis tracking control is realized based on winding current, achieve stable for switching, provides the basis for the current source, high efficiency. Through the analysis of the current closing, it proposes the methods to obtain better dynamic characteristics, and through the use of PID improved hysteresis control method, realizes the control of closing characteristics of the circuit breaker, the on-off switch time dispersion control in less than 0.3ms.
In order to realize the optimization of dynamic characteristics of permanent magnetic actuator when closing, the variable voltage variable output energy (VVVE) of the circuit breaker closing coil current control method. Analysis of the closing process of the permanent magnetic actuator open-loop state, using curve fitting is given current during closing process, and the parameters of the fitting equation in the method described in detail, an example is given to prove the accuracy of fitting method. The method is proposed based on the regulation of VVVE, adjust the coarse implementation closing time by VV, in improving the average closing speed at the same time, limiting the speed of the moving contact stiffness, through the realization of the VE regulation the closing time of fine-tuning, and the control speed. Just because of the increase of switching speed and reduce the average closing collision energy is always a contradiction between the circuit breaker closing process, put forward VVVE control scheme It provides a good solution to reduce the impact of the above contradictions.
In order to realize the synchronous closing, this paper designed the permanent magnetic vacuum circuit breaker controller, the main controller of the hardware structure are described. Key technology combined with synchronous implementation, describes the VWE in the synchronous closing show excellent performance control process. Although WVE is obtained in 12kV monostable vacuum circuit breaker based on experiment results, but through the controller, the WVE control strategy is used to control the experimental 40.5kV monostable permanent magnetic vacuum circuit breaker, which indicates that the VVVE control strategy is the general. The closing time of 40.5kV vacuum circuit breaker with monostable in high temperature dispersion are analyzed, and based on the study of how the temperature compensation control circuit breaker closing time, the compensation equation is given for 40.5kV vacuum circuit breaker with monostable.

【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TM561.2

【参考文献】