一种改进的磁悬浮轴承开关功率放大器数字单周期控制  

An Improved Digital One-Cycle Control Algorithm for Switching Power Amplifier in Magnetic Bearings

作　　者：李诗文 邓智泉[1] 曹鑫[1] 刘程子[2] 李克翔[1] Li Shiwen;Deng Zhiquan;Cao Xin;Liu Chengzi;Li Kexiang(College of Automation Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China;College of Automation Nanjing University of Posts and Telecommunications,Nanjing 210023,China)

机构地区：[1]南京航空航天大学自动化学院,南京211106 [2]南京邮电大学自动化学院,南京210023

出　　处：《电工技术学报》2020年第2期274-283,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金（51577087,51477074,51607096）;江苏省自然科学基金（bk20160896）资助项目

摘　　要：该文提出一种改进的磁悬浮轴承开关功率放大器的数字单周期控制算法。单周期控制算法具有算法简单、易实现、响应速度快等优点,但传统的单周期算法,存在开关次数不均衡,电流幅值失真较明显,部分开关周期无法实现跟踪目标的问题。该文分析单相全桥主电路的九种开关状态,在此基础上优化单周期控制的开关逻辑;在全周期考虑磁轴承线圈电阻压降的前提下,分析单周期控制的原理,优化充放电周期的判断准则,从而建立更精确的算法模型。对改进前后的数字单周期控制算法进行仿真分析和实验验证,结果表明:改进型单周期算法控制下,实际电流能准确跟踪给定电流,证明了算法的可行性;4个开关管的开关次数均衡,实际电流失真更小,控制精度更高,验证了算法的优越性。An improved digital one-cycle control algorithm for switching power amplifier in magnetic bearings is proposed.Digital one-cycle control has the advantages of simple structure,easy realization and rapid response.However,the traditional one-cycle algorithm has some problems such as unbalanced switching frequency,obvious distortion of current amplitude,and some switching cycles cannot achieve tracking targets.In this paper,nine switching states of single-phase full-bridge circuit were analyzed,and the switching logic was optimized.The principle of one-cycle control was analyzed with the consideration of resistance voltage drop,and the judgment criterion of charge and discharge period is optimized for more precise control.Simulation and experiments were carried out.The results show that the actual current can accurately track the given current under the control of the improved one-cycle algorithm,which proves the feasibility of the algorithm.The proposed algorithm can realize the switching frequency equalization of four switches,and has smaller distortion of actual current and higher control accuracy.

关 键 词：磁悬浮轴承 开关功放 数字单周期控制 电流控制 

分 类 号：TN722.7[电子电信—电路与系统]