独立励磁直流发电系统的广义预测电压控制策略  

Generalized Predictive Voltage Control Strategy for Independent Excitation DC Power Generation System

作　　者：夏宇航 王宇[1] 陈凯 张成糕 Xia Yuhang;Wang Yu;Chen Kai;Zhang Chenggao(School of Automation Nanjing University of Aeronautics and Astronautics,Nanjing 211100,China)

机构地区：[1]南京航空航天大学自动化学院,南京211100

出　　处：《电工技术学报》2023年第12期3199-3207,共9页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51977107,U2141227);江苏省六大人才高峰(XNYQC-005);航空科学基金(2020HKZ0001)资助项目。

摘　　要：车载/机载电源系统对直流发电机的电压动态特性提出了要求。该文提出一种基于负载励磁映射关系的广义预测电压控制方法,替代传统的电压环PI调节器,以提高系统在负载扰动下的电压回复动态性能。采用增量式预测输出结合负载电流反馈的控制结构,经过负载励磁拟合函数得到励磁电流指令值。构建控制系统离散域下的传递函数,进行稳定性与系统抗负载扰动能力分析,考察控制参数与系统参数对控制性能的影响。实验证明,所提控制方案在系统负载突加和突卸情况下能够有效地抑制低电压与过电压,使系统平滑地过渡到稳态,拥有较快的动态响应速度。The voltage closed-loop control based on the PI regulator is generally adopted in the independent excitation DC power generation system.PI control can ensure the steady-state control accuracy of the system output voltage.However,limited by the fixed PI regulator parameters and the system’s nonlinearity,the dynamic regulation characteristics of the output voltage may have problems such as slow response speed and extensive voltage recovery overshooting when the system faces load mutation under different working conditions.In recent years,predictive control has been widely used in power electronics with its characteristics of fast dynamic response and strong resistance to disturbance.Among them,the generalized predictive control(GPC)based on multi-step prediction has the characteristics of high flexibility in parameter design and strong robustness when the prediction length is sufficient.As an alternative to PI control,it can improve the dynamic voltage performance of the system under load disturbance.Introducing load current feedforward is a standard method to solve the problem of the poor dynamic performance of PI control.Considering that the relation curve between excitation and load of the power generation system is coupled with the parameter of generator speed,the fitting function relation surface of excitation,load,and speed is constructed.After adding the feedback value of load current to the total generalized predicted output,the excitation current command value is obtained through the fitting function.The control loop of the system is approximately linearized by the fitting function,and the transfer function in the discrete domain of the control system is constructed to analyze the system's stability and ability to resist load disturbance.The system’s stability is judged by the closed-loop pole position in the discrete domain.When the weight coefficient r of the performance index function is small,the system is unstable.When the predicted length N,the weight factor RF,and the estimated capacitance value

关 键 词：独立励磁直流发电系统 广义预测控制 负载扰动 动态性能 

分 类 号：TM301[电气工程—电机]