【作者】 陈炜；

【导师】 汤龙飞；

【作者基本信息】 福州大学 ， 电气工程（专业学位）， 2022， 硕士

【摘要】 随着中国电能结构改革的逐步推进,不稳定的清洁能源将向电力系统大规模渗透,导致节点电压越限、局部潮流倒送、功率分布不均、谐波污染等问题愈发频繁。因此未来电网需要更为灵活、频繁的调度与控制,方能满足电力系统稳定可靠的要求。而电磁开关作为电力系统基础的控制元件,其智能化研究愈发受到社会的关注,对其性能指标和工作可靠性也提出了更高的要求。本文引入现代控制及人工智能方法对接触器这一典型电磁开关的闭环控制技术进行研究,主要完成以下几个方面的工作:(1)在接触器的起动和分断过程中设计积分型磁链观测器;在稳定保持过程中设计闭环状态磁链观测器,通过加入合适的反馈矩阵,实现观测磁链快速跟踪真实磁链。利用接触器电磁参量间的“二元一一对应”关系,采用BP神经网络构建以线圈电流和磁链为输入,以电磁吸力为输出的吸力观测器,实现了接触器磁链及吸力起动、保持及分断全过程的准确实时观测。(2)设计了接触器的线圈驱动电路及其电压状态选择表,采用滞环控制方法即可根据闭环误差自动选择合适的电压状态。之后,首次提出了接触器的磁链单闭环自校正控制:在保持过程中使磁链逐级下跌,触发动铁心回弹,同时采用磁链观测器检测动静铁心的早期分离信号,据此确定临界磁链,并及时施加短时强激磁,在触头尚未分离时及时阻止铁心继续回弹。最后,根据这一校正后的临界磁链来自动设定闭环控制中的磁链参考值,即可实现接触器起动过程的弹跳抑制和保持过程的节能运行。(3)在吸力观测器的基础上进一步设计弹簧反力观测器,并首次提出了接触器的直接吸力闭环控制策略:以观测吸力作为反馈,在观测反力的基础上叠加一恒定裕量作为吸力参考,通过滞环控制方式实现了接触器的直接吸力控制。该控制方法既可保证接触器快速、可靠的动作,又能降低合闸弹跳并兼顾节能。通过构建的联合仿真及快速控制原型验证系统验证了控制方案的理论及实际可行性,根据验证结果总结了接触器在磁链及吸力闭环控制下的性能特点,对接触器的高性能控制具有重要意义。研究成果也可为永磁接触器、永磁断路器等其他电磁开关智能控制技术的实施提供有益借鉴。更多还原

【Abstract】 With the gradual progress of electric energy structure reform in China,unstable clean energy will penetrate into the power system on a large scale,leading to more frequent problems such as out-of-limit node voltage,local power flow back,uneven power distribution,harmonic pollution and so on.Therefore,the future grid needs more flexible and frequent dispatching and control to meet the requirements of stable and reliable power system.As a basic control element of the power system,electromagnetic switches have attracted more and more attention from the society for its intelligent research,and higher requirements for its performance index and work reliability have been put forward.This paper introduces the modern control and artificial intelligence methods to study the closed-loop control technology for the contactor,a typical electromagnetic switch.The main contents are as follows:(1)The integral flux linkage observer is designed during the making and breaking process of the contactor;the closed-loop state flux linkage observer is designed in the stable closing process,and the real flux linkage can be tracked quickly by adding appropriate feedback matrix.Based on the binary one-to-one relationship between the electromagnetic parameters of the contactor,a electromagnetic force observer with the coil current and flux linkage as the input and electromagnetic force as the output is constructed by using BP neural network,which realizes the accurate and real-time observation of the flux linkage and electromagnetic force in the whole process of making,closing and breaking of the contactor.(2)The coil driving circuit of the contactor and its voltage state selection table are designed and the hysteresis control method is adopted to automatically select the appropriate voltage state according to the closed-loop error.Later,for the first time,the self-correcting control strategy of a single flux linkage closed loop for a contactor is proposed: in the closing process,the flux linkage is reduced step by step to make the movable core rebound;at the same time,a flux linkage observer is used to detect the early separation signal of the movable and static cores,and the critical flux linkage is determined based on it;then,a short-time strong excitation is applied to prevent the continued rebound of the movable core before contactor separation.Finally,the flux linkage reference value in the closed-loop control can be automatically set according to the corrected critical flux linkage,which can realize the bounce inhibition in the making process and energy-saving operation in the closing process of the contactor.(3)On the basis of the electromagnetic force observer,the spring reaction force observer is further designed,and the direct electromagnetic force closed-loop control strategy of the contactor is proposed for the first time.A constant force margin is added to the real-time reaction force as the reference curve,and the real-time observed electromagnetic force is used as the feedback;thus,direct electromagnetic force closedloop control is realized through hysteresis regulation.This control method can not only ensure fast and reliable action of the contactor,but also reduce the contact bounces and save energy.The theoretical and practical feasibility of the control scheme is verified by the constructed co-simulation and rapid control prototype verification system.According to the verification results,the performance characteristics of the contactor under the flux linkage and electromagnetic force closed-loop control are summarized,which is of great significance to the high performance control of the contactor.The research results can also provide useful reference for the implementation of other electromagnetic switch intelligent control technology such as the permanent magnet contactor and the permanent magnet circuit breaker.更多还原