电工技术学报  2024, Vol. 39 Issue (6): 1737-1748    DOI: 10.19595/j.cnki.1000-6753.tces.222284
电机及其系统 |
计及总损耗功率的电动汽车母线电容主动快速放电方法
张晓军1, 杨家强1, 周宇晨2
1.浙江大学电气工程学院 杭州 310027;
2.浙江大学工程师学院 杭州 310015
Active Fast Discharge Method of Bus Capacitor for Electric Vehicle with Total Power Loss
Zhang Xiaojun1, Yang Jiaqiang1, Zhou Yuchen2
1. School of Electrical Engineering Zhejiang University Hangzhou 310027 China;
2. School of Engineers Zhejiang University Hangzhou 310015 China
全文: PDF (4636 KB)   HTML
输出: BibTeX | EndNote (RIS)      
摘要 

针对电动汽车遇到碰撞等紧急情况时,高压驱动系统母线电容电压需迅速降到安全电压(60 V),而传统基于PI控制的母线电容主动放电方法存在鲁棒性差、放电时间长和安全性低的问题,提出一种计及总损耗功率的电动汽车母线电容快速放电方法。首先,建立以永磁同步电机绕组作为泄放电阻的母线电容能量流动模型,将逆变器损耗、电机绕组铜耗、电机电感储能等损耗作为总损耗,利用扩展滑模观测器(ESMO)对总损耗功率进行估算,并通过Lyapunov稳定性理论对ESMO的稳定性进行了证明。然后,将观测的总损耗功进行前馈补偿,从而使母线电压快速降低并稳定在安全电压。仿真和实验结果表明,与现有主动放电方法相比,所提放电方法不仅显著减小了放电时间,而且提高了快速放电的鲁棒性和安全性。

服务
把本文推荐给朋友
加入我的书架
加入引用管理器
E-mail Alert
RSS
作者相关文章
张晓军
杨家强
周宇晨
关键词 电动汽车永磁同步电机总损耗功率估计扩展滑模观测器母线电容放电    
Abstract

When electric vehicles (EVs) encounter an emergency, the dc-bus voltage of EVs equipped with the high-voltage drive system needs to be reduced to safe voltage (60 V) as soon as possible. To drop the dc-bus capacitor voltage to a safe voltage, a winding-based active discharge method was proposed. However, traditional active discharge based on PI controller has poor robustness, long discharge time, and low safety, which cannot meet the discharge requirements of the United Nation Vehicle Regulation ECCE R94. This paper proposes an active discharge method for EVs with total power loss to reduce the discharge time and enhance the robustness.
Firstly, the d-axis weakened current is calculated using the permanent magnet synchronous motor winding as the bleeding resistor. Then, the traditional active discharge method based on the PI controller is analyzed. Secondly, the dc-bus capacitor energy flow model is established. More importantly, the extended sliding mode observer (ESMO) is introduced to address long discharge time and poor robustness issues. The ESMO can observe the total loss, which consists of inverter loss, motor winding copper consumption, motor inductance energy storage, and other losses. The stability of ESMO is proved by the Lyapunov stability theory. Finally, observed total discharge loss can be feedforward compensated by the designed control law. Compared with the conventional discharge method, the influence of total power loss and motor speed on the dc-bus capacitor voltage is well suppressed, and the dc-bus capacitor voltage and motor speed are decoupled in the proposed strategy.
Experimental results show that the DC-bus voltage of the proposed method drops to a safe voltage within 0.2 s, faster than traditional active discharge method-based PI controller (1.2 s) and disturbance observer (0.3 s). In contrast, the discharge time is shorter with the active discharge method-based disturbance observer because the convergence rate is faster than the disturbance observer. The experiment with parameter mismatch proves that the parameter error can be observed and compensated by the ESMO. Furthermore, electric vehicle drive systems' power density and reliability are further improved by eliminating the complicated drain circuit.
The following conclusions can be obtained: (1) The traditional discharge method-based PI controller has the problem of changing the steady-state operating point with the motor speed, which could not meet the requirements of fast and safe discharge of the dc-bus capacitor in emergencies. (2) The discharge model with PMSM winding as the bleeding resistor is established, and the relationship between the dc-bus capacitor voltage and the total power loss of the system is deduced. Moreover, the observed total loss of the system can be feedforward compensated in the proposed discharge method, effectively suppressing the voltage pulsation when the dc-bus voltage reduces to the safe voltage. Hence, the discharge time is short, and the robustness and safety of the system are improved. (3) The simulation and experimental results show that the proposed control method for electric vehicles with total power loss estimation has strong robustness, high safety, strong practicability, and engineering application value.

Key wordsElectric vehicle    permanent magnet synchronous motor (PMSM)    estimated total power loss    extended sliding mode observer    DC-bus capacitor discharge   
收稿日期: 2022-12-12     
PACS: TM351  
基金资助:

浙江省自然科学基金重点基金资助项目(LCZ19E070001)

通讯作者: 杨家强 男,1970年生,教授,博士生导师,研究方向为电机系统及其控制。E-mail: yjq1998@163.com   
作者简介: 张晓军 男,1991年生,博士,讲师,研究方向为永磁同步电机驱动系统及其控制。E-mail: eezxj1991@126.com
引用本文:   
张晓军, 杨家强, 周宇晨. 计及总损耗功率的电动汽车母线电容主动快速放电方法[J]. 电工技术学报, 2024, 39(6): 1737-1748. Zhang Xiaojun, Yang Jiaqiang, Zhou Yuchen. Active Fast Discharge Method of Bus Capacitor for Electric Vehicle with Total Power Loss. Transactions of China Electrotechnical Society, 2024, 39(6): 1737-1748.
链接本文:  
https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.222284          https://dgjsxb.ces-transaction.com/CN/Y2024/V39/I6/1737