|
|
|
| Transient Voltage Support Strategy for Hybrid Multi-Converter of Controlled Voltage/Current Source Converter |
| Yang Ming1, Cao Wu1, Zhao Jianfeng1, Zhu Lingzhi2, Wang Baoji3 |
1. School of Electrical Engineering Southeast University Nanjing 210096 China;
2. China Electric Power Research Institute (Nanjing) Nanjing 210003 China;
3. Sungrow Power Supply Co. Ltd Hefei 230009 China |
|
|
|
Abstract The increasing proportion of renewable energy makes the power system have obvious power electronic characteristics. The converters used for renewable energy is more sensitive to system voltage due to its weak high-low voltage ride-through capability. Under the condition of large disturbance of transient voltage condition, the renewable energy converter is very easy to be locked and cut off. The stable operation of high voltage direct current transmission also highly depends on the transient voltage stability. Therefore, the transient voltage problem of new type power grid with high proportion of renewable energy is the key to the safe and stable operation of the system.
Currently, the transient active support capability of the converter is not available due to synchronization problems and reactive power output ability under transient voltage conditions. To solve the problems existing in active support of renewable energy station, controlled voltage/current source converters are connected in parallel to form a hybrid multi-converter system. The controlled voltage source converter realizes power angle control through power control. The synchronization control is not affected by system transient voltage. Therefore, stable synchronization conditions are provided by controlled voltage source converters. The controlled current source converter can output fast and accurate reactive power support. Based on the analysis and summary of active transient voltage support requirements of renewable energy station, a hybrid multi-converter transient voltage support strategy of controlled voltage/current source converter is proposed to improve the transient voltage stability of renewable energy station and enable it to support transient voltage actively.
Controlled voltage source converters are prone to lose voltage source characteristics and reduce reactive power output capabilities because of the large power fluctuations under transient conditions. The overcurrent degree of the converter is flexibly limited by virtual impedance to improve the adaptability of the controlled voltage source converter to transient conditions. By suppressing the response to voltage fluctuations in the active power control of the converter, the effect of increasing the active power fluctuation damping can be achieved. The reactive power output capability of the controlled voltage source converter can also be guaranteed while promoting the stable operation of the converter. The flexible limiting of transient current combined with transient active power damping control ensures the voltage control stability and reactive power output capability of the controlled voltage source converter under transient conditions.
The steady state of the controlled current source converter is mainly output active power. In the transient state, it is necessary to adjust its power output target according to the voltage change. The reactive power compensation demand is calculated under the current condition. The compensation demand is superimposed on the current reactive power control target. And the active power control target is accordingly reduced. So the adaptive compensation control of the controlled current source converter is realized. The transient voltage reactive power support of the controlled current source converter can be realized under the limitation of the converter capacity.
The following conclusions can be drawn from the simulation and experimental results: the proposed strategy can fully combine the advantages of the controlled voltage source converter and the controlled current source converter. The controlled voltage source converter can ensure the control voltage stability in the transient process and the output capability of the hybrid multi-converter system. Under the stable condition of phase locking, the controlled current source converter can take into account the stable and reliable reactive power output of its own operation. The hybrid multi-converter system based on controlled voltage/current source converter can meet the key requirements of transient voltage support and improve the voltage stable level under transient conditions.
The hybrid multi-machine system with proposed strategy can be taken as the basis of further research on transient voltage support. The coordinated control of converters and other reactive power compensation equipment in renewable energy stations can be studied to further improve the transient voltage active support capability of renewable energy station.
|
|
Received: 27 April 2022
|
|
|
|
|
|
[1] 辛保安, 郭铭群, 王绍武, 等. 适应大规模新能源友好送出的直流输电技术与工程实践[J]. 电力系统自动化, 2021, 45(22): 1-8.
Xin Baoan, Guo Mingqun, Wang Shaowu, et al.Friendly HVDC transmission technologies for large-scale renewable energy and their engineering practice[J]. Automation of Electric Power Systems, 2021, 45(22): 1-8.
[2] 刘其辉, 逄思敏, 吴林林, 等. 大规模风电汇集系统电压不平衡机理、因素及影响规律[J]. 电工技术学报, 2022, 37(21): 5435-5450.
Liu Qihui, Pang Simin, Wu Linlin, et al.The mechanism, factors and influence rules of voltage imbalance in wind power integration areas[J]. Transactions of China Electrotechnical Society, 2022, 37(21): 5435-5450.
[3] 毛安家, 马静, 蒯圣宇, 等. 高比例新能源替代常规电源后系统暂态稳定与电压稳定的演化机理[J]. 中国电机工程学报, 2020, 40(9): 2745-2756.
Mao Anjia, Ma Jing, Kuai Shengyu, et al.Evolution mechanism of transient and voltage stability for power system with high renewable penetration level[J]. Proceedings of the CSEE, 2020, 40(9): 2745-2756.
[4] 郑超, 张鑫, 吕盼, 等. VSC-HVDC与弱交流电网混联系统大扰动行为机理及稳定控制[J]. 中国电机工程学报, 2019, 39(3): 629-641.
Zheng Chao, Zhang Xin, Lü Pan, et al.Study on the large disturbance behavior mechanism and stability control strategy for VSC-HVDC and weak AC hybrid system[J]. Proceedings of the CSEE, 2019, 39(3): 629-641.
[5] 王长江, 姜涛, 陈厚合, 等. 基于相位校正李雅普诺夫指数的电力系统暂态电压稳定评估[J]. 电工技术学报, 2021, 36(15): 3221-3236.
Wang Changjiang, Jiang Tao, Chen Houhe, et al.Transient voltage stability assessment of power systems based on phase correction maximum Lyapunov exponent[J]. Transactions of China Electrotechnical Society, 2021, 36(15): 3221-3236.
[6] 王熙纯, 刘纯, 林伟芳, 等. 风机故障穿越特性对大规模风电直流外送系统暂态过电压的影响及参数优化[J]. 电网技术, 2021, 45(12): 4612-4621.
Wang Xichun, Liu Chun, Lin Weifang, et al.Influence of wind turbine fault ride-through characteristics on transient overvoltage of large-scale wind power DC transmission systems and parameter optimization[J]. Power System Technology, 2021, 45(12): 4612-4621.
[7] 张炎, 丁明, 韩平平, 等. 直流闭锁后风电送端系统暂态稳定及控制策略研究[J]. 电工技术学报, 2020, 35(17): 3714-3726.
Zhang Yan, Ding Ming, Han Pingping, et al.Study on the transient stability and control schemes of the sending-end system involving wind power after UHVDC block[J]. Transactions of China Electrote-chnical Society, 2020, 35(17): 3714-3726.
[8] 于琳, 孙华东, 徐式蕴, 等. 电力电子设备接入电压支撑强度量化评估指标综述[J]. 中国电机工程学报, 2022, 42(2): 499-515.
Yu Lin, Sun Huadong, Xu Shiyun, et al.Overview of strength quantification indexes of power system with power electronic equipment[J]. Proceedings of the CSEE, 2022, 42(2): 499-515.
[9] 陈磊, 刘永奇, 戴远航, 等. 电力电子接口新能源并网的暂态电压稳定机理研究[J]. 电力系统保护与控制, 2016, 44(9): 15-21.
Chen Lei, Liu Yongqi, Dai Yuanhang, et al.Study on the mechanism of transient voltage stability of renewable energy source with power electronic interface[J]. Power System Protection and Control, 2016, 44(9): 15-21.
[10] Cheng Peng, Li Kongyuan, Wu Chao, et al.Flexible power regulation and limitation of voltage source inverters under unbalanced grid faults[J]. CES Transactions on Electrical Machines and Systems, 2022, 6(2): 153-161.
[11] 金一丁, 于钊, 李明节, 等. 新一代调相机与电力电子无功补偿装置在特高压交直流电网中应用的比较[J]. 电网技术, 2018, 42(7): 2095-2102.
Jin Yiding, Yu Zhao, Li Mingjie, et al.Comparison of new generation synchronous condenser and power electronic reactive-power compensation devices in application in UHV DC/AC grid[J]. Power System Technology, 2018, 42(7): 2095-2102.
[12] 苏东亮, 邓化运. 新型大容量调相机原理及运行控制[J]. 电气技术, 2021, 22(6): 87-91.
Su Dongliang, Deng Huayun.Principle and control of new type large capacity synchronous compensator[J]. Electrical Engineering, 2021, 22(6): 87-91.
[13] Yu Hui, Awal M A, Tu Hao, et al.Comparative transient stability assessment of droop and dispatchable virtual oscillator controlled grid-connected inverters[J]. IEEE Transactions on Power Electronics, 2021, 36(2): 2119-2130.
[14] Fang Jingyang, Li Xiaoqiang, Li Hongchang, et al.Stability improvement for three-phase grid-connected converters through impedance reshaping in quadrature-axis[J]. IEEE Transactions on Power Electronics, 2018, 33(10): 8365-8375.
[15] Pei Jinxin, Yao Jun, Liu Ruikuo, et al.Characteristic analysis and risk assessment for voltage-frequency coupled transient instability of large-scale grid-connected renewable energy plants during LVRT[J]. IEEE Transactions on Industrial Electronics, 2020, 67(7): 5515-5530.
[16] 杨树德, 同向前, 尹军, 等. 增强并网逆变器对电网阻抗鲁棒稳定性的改进前馈控制方法[J]. 电工技术学报, 2017, 32(10): 222-230, 240.
Yang Shude, Tong Xiangqian, Yin Jun, et al.An improved grid voltage feedforward strategy for grid-connected inverter to achieve high robust stability against grid-impedance variation[J]. Transactions of China Electrotechnical Society, 2017, 32(10): 222-230, 240.
[17] 张兴, 李明, 郭梓暄, 等. 新能源并网逆变器控制策略研究综述与展望[J]. 全球能源互联网, 2021, 4(5): 506-515.
Zhang Xing, Li Ming, Guo Zixuan, et al.Review and perspectives on control strategies for renewable energy grid-connected inverters[J]. Journal of Global Energy Interconnection, 2021, 4(5): 506-515.
[18] Rocabert J, Luna A, Blaabjerg F, et al.Control of power converters in AC microgrids[J]. IEEE Trans-actions on Power Electronics, 2012, 27(11): 4734-4749.
[19] Fang Jingyang, Deng Han, Goetz S M.Grid impedance estimation through grid-forming power converters[J]. IEEE Transactions on Power Electronics, 2021, 36(2): 2094-2104.
[20] Rosso R, Wang Xiongfei, Liserre M, et al.Grid-forming converters: control approaches, grid-synch-ronization, and future trends—a review[J]. IEEE Open Journal of Industry Applications, 2021, 2: 93-109.
[21] 屈子森. 高比例新能源电力系统电压源型变流器同步稳定性分析与控制技术[D]. 杭州: 浙江大学, 2021.
[22] Wu Heng, Wang Xiongfei.Design-oriented transient stability analysis of grid-connected converters with power synchronization control[J]. IEEE Transactions on Industrial Electronics, 2019, 66(8): 6473-6482.
[23] Pan Donghua, Wang Xiongfei, Liu Fangcheng, et al.Transient stability of voltage-source converters with grid-forming control: a design-oriented study[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020, 8(2): 1019-1033.
[24] Zhang Haobo, Xiang Wang, Lin Weixing, et al.Grid forming converters in renewable energy sources dominated power grid: control strategy, stability, application, and challenges[J]. Journal of Modern Power Systems and Clean Energy, 2021, 9(6): 1239-1256.
[25] 张宇, 蔡旭, 张琛, 等. 并网变换器的暂态同步稳定性研究综述[J]. 中国电机工程学报, 2021, 41(5): 1687-1702.
Zhang Yu, Cai Xu, Zhang Chen, et al.Transient synchronization stability analysis of voltage source converters: a review[J]. Proceedings of the CSEE, 2021, 41(5): 1687-1702.
[26] 黄林彬, 辛焕海, 鞠平, 等. 电力电子并网装备的同步稳定分析与统一同步控制结构[J]. 电力自动化设备, 2020, 40(9): 10-25.
Huang Linbin, Xin Huanhai, Ju Ping, et al.Synchronization stability analysis and unified synchronization control structure of grid-connected power electronic devices[J]. Electric Power Auto-mation Equipment, 2020, 40(9): 10-25.
[27] Taul M G, Wang Xiongfei, Davari P, et al.An overview of assessment methods for synchronization stability of grid-connected converters under severe symmetrical grid faults[J]. IEEE Transactions on Power Electronics, 2019, 34(10): 9655-9670.
[28] Hu Qi, Fu Lijun, Ma Fan, et al.Large signal synchronizing instability of PLL-based VSC connected to weak AC grid[J]. IEEE Transactions on Power Systems, 2019, 34(4): 3220-3229.
[29] 杨柳. 逆变器并联系统的研究[D]. 天津: 天津大学, 2014.
[30] Du Wei, Tuffner F K, Schneider K P, et al.Modeling of grid-forming and grid-following inverters for dynamic simulation of large-scale distribution systems[J]. IEEE Transactions on Power Delivery, 2021, 36(4): 2035-2045.
[31] 杨雄超. 孤岛模式下多变流器微网分层协调控制策略及实验研究[D]. 成都: 电子科技大学, 2020.
[32] 柴秀慧, 张纯江, 柴建国, 等. 改进互联通信荷电状态下垂控制及功率均衡优化[J]. 电工技术学报, 2021, 36(16): 3365-3374.
Chai Xiuhui, Zhang Chunjiang, Chai Jianguo, et al.Improved interconnected communication state of charge droop control and power balance optimization[J]. Transactions of China Electrotechnical Society, 2021, 36(16): 3365-3374.
[33] Mahmood H, Michaelson D, Jiang Jin.Accurate reactive power sharing in an islanded microgrid using adaptive virtual impedances[J]. IEEE Transactions on Power Electronics, 2015, 30(3): 1605-1617.
[34] Urtasun A, Sanchis P, Guinjoan F, et al.Parameter-independent battery control based on series and parallel impedance emulation[J]. IEEE Access, 2019, 7: 70021-70031.
[35] Li Ming, Zhang Xing, Zhao Wei.A novel stability improvement strategy for a multi-inverter system in a weak grid utilizing dual-mode control[J]. Energies, 2018, 11(8): 2144.
[36] 涂春鸣, 李庆, 郭祺, 等. 具备电压质量调节能力的串并联一体化多功能变流器[J]. 电工技术学报, 2020, 35(23): 4852-4863.
Tu Chunming, Li Qing, Guo Qi, et al.Research on series-parallel integrated multifunctional converter with voltage quality adjustment[J]. Transactions of China Electrotechnical Society, 2020, 35(23): 4852-4863.
[37] 裴金鑫, 姚骏, 黄森, 等. 电网短路故障下新能源并网变换器的暂态同步机制及其自适应稳定控制策略[J].中国电机工程学报, 2022, 42(16): 5922-5934.
Pei Jinxin, Yao Jun,Huang Sen, et al.Transient synchronization mechanism and adaptive stability control strategy for renewable energy grid-connected converter under grid faults[J]. Proceedings of the CSEE, 2022, 42(16): 5922-5934
[38] Me S P, Zabihi S, Blaabjerg F, et al.Adaptive virtual resistance for postfault oscillation damping in grid-forming inverters[J]. IEEE Transactions on Power Electronics, 2022, 37(4): 3813-3824.
[39] 全相军, 张从越, 吴在军, 等. 电压控制型并网逆变器瞬时功率降阶控制方法[J]. 电力系统自动化, 2021, 45(2): 139-147.
Quan Xiangjun, Zhang Congyue, Wu Zaijun, et al.Order-reduced control method of instantaneous power for voltage-controlled grid-connected inverter[J]. Automation of Electric Power Systems, 2021, 45(2): 139-147.
[40] 赵峰, 帅智康, 彭也伦, 等. 含电流限幅器的逆变器暂态稳定性评估方法[J]. 中国电机工程学报, 2021, 41(6): 2245-2255.
Zhao Feng, Shuai Zhikang, Peng Yelun, et al.Evaluation method for transient stability of inverter containing current limiter[J]. Proceedings of the CSEE, 2021, 41(6): 2245-2255.
[41] Bottrell N, Green T C.Comparison of current-limiting strategies during fault ride-through of inverters to prevent latch-up and wind-up[J]. IEEE Transactions on Power Electronics, 2014, 29(7): 3786-3797.
[42] Paquette A D, Divan D M.Virtual impedance current limiting for inverters in microgrids with synchronous generators[J]. IEEE Transactions on Industry Applications, 2015, 51(2): 1630-1638.
[43] Chen Zhe, Lasseter R H, Jahns T M.Active power reserve control for grid-forming PV sources in microgrids using model-based maximum power point estimation[C]//2019 IEEE Energy Conversion Congress and Exposition (ECCE), Baltimore, MD, USA, 2019: 41-48.
[44] Peng Qiao, Tang Zhongting, Yang Yongheng, et al.Event-triggering virtual inertia control of PV systems with power reserve[J]. IEEE Transactions on Industry Applications, 2021, 57(4): 4059-4070.
[45] Quan Xiangjun, Yu Ruiyang, Zhao Xin, et al.Photovoltaic synchronous generator: architecture and control strategy for a grid-forming PV energy system[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020, 8(2): 936-948. |
|
|
|
2023, Vol. 38 
