RESEARCH AND ENGINEERING APPLICATION OF INTERMEDIATE FREQUENCY ISOLATED PV &#x000b1;35 kV/500 kW DC CONVERTER

Liu Fang; Wu Ziqun; Zhou Jianjian; Liu Shiquan; Wang Haodong

doi:10.19912/j.0254-0096.tynxb.2021-1076

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Acta Energiae Solaris Sinica ›› 2023, Vol. 44 ›› Issue (2) : 427-435. DOI: 10.19912/j.0254-0096.tynxb.2021-1076

RESEARCH AND ENGINEERING APPLICATION OF INTERMEDIATE FREQUENCY ISOLATED PV ±35 kV/500 kW DC CONVERTER

Liu Fang, Wu Ziqun, Zhou Jianjian, Liu Shiquan, Wang Haodong

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Abstract

This paper firstly proposes an intermediate frequency isolated photovoltaic ±35 kV/500 kW DC converter. The DC converter consists of a three-phase T-type three-level intermediate frequency parallel inverter module, an intermediate frequency 400 Hz 24-pulse phase-shift boosting transformer, a three-phase diode rectifier bridge and a high-voltage filter circuit. The converter has the advantages of high boost ratio, simple structure and low costs. Secondly,in order to realize the real-time equalization of the active and reactive power of the parallel module of the inverter,a master-slave power control scheme of instantaneous power equalization is adopted in this paper. Then, an improved LCL filter parameter design method based on reactive power compensation of intermediate frequency transformer is proposed to improve the efficiency of the system. Finally,through Matlab/Simulink simulation and the photovoltaic power generation medium-voltage DC collection field demonstration project built by Zhang Bei National Research and Development （Experiment） Center of Large Wind Power Grid Connected System, the control method and design concept of the proposed DC converter are verified. The maximum efficiency is 96.33% and the boost ratio is as high as 88. The output voltage is ±35 kV. Simulation and experimental results prove the feasibility of the proposed DC converter.

Key words

PV power / DC converter / intermediate frequency isolation / master-slave control / high step-up ratio / LCL filter design

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Liu Fang, Wu Ziqun, Zhou Jianjian, Liu Shiquan, Wang Haodong. RESEARCH AND ENGINEERING APPLICATION OF INTERMEDIATE FREQUENCY ISOLATED PV ±35 kV/500 kW DC CONVERTER[J]. Acta Energiae Solaris Sinica. 2023, 44(2): 427-435 https://doi.org/10.19912/j.0254-0096.tynxb.2021-1076

References

[1] 韩民晓, 谢文强, 曹文远, 等. 中压直流配电网应用场景与系统设计[J]. 电力系统自动化, 2019, 43(23): 2-11, 89.
HAN M X, XIE W Q, CAO W Y, et al.Application scenarios and system design of medium-voltage DC distribution network[J]. Automation of electric power systems, 2019, 43(23): 2-11,89.
[2] 余滢婷, 刘飞, 查晓明, 等. 光伏电站直流汇集系统电压等级序列研究[J]. 太阳能学报, 2020, 41(10): 182-189.
YU Y T, LIU F, ZHA X M, et al.DC convergence system voltage class series for PV power station[J]. Acta energiae solaris sinica, 2020, 41(10): 182-189.
[3] SURYADEVARA R, PARSA L.Full-bridge ZCS-converter-based high-gain modular DC-DC converter for PV integration with medium-voltage DC grids[J]. IEEE transactions on energy conversion, 2019, 34(1): 302-312.
[4] 陈武, 吴小刚, 蒋玮, 等. 一种适用于新能源并网的谐振升压变换器[J]. 电工技术学报, 2016, 31(8): 27-33.
CHEN W, WU X G, JIANG W, et al.A step-up resonant converter for grid-connected renewable energy sources[J]. Transactions of China Electrotechnical Society, 2016, 31(8): 27-33.
[5] AN F, ZHAO B, WHANG J, et al.An adaptive control method of DC transformers imitating AC transformers for flexible DC distribution application[C]//2020 IEEE Applied Power Electronics Conference and Exposition(APEC), New Orleans, LA, USA, 2020.
[6] SIDDIQUE H, DONCKER R D.Evaluation of DC collector-grid configurations for large photovoltaic parks[J]. IEEE transactions on power delivery, 2018, 33(1): 311-320.
[7] 孙长江, 张建文, 蔡旭, 等. 隔离型MMC直流变压器的电流源运行[J]. 中国电机工程学报, 2016, 36(7): 1977-1986.
SUN C J, ZHANG J W, CAI X, et al.Current-fed operation of isolated MMC-based DC transformer[J]. Proceedings of the CSEE, 2016, 36(7): 1977-1986.
[8] 张颖, 荆龙, 吴学智, 等. 应用于直流电网的新型直流自耦变压器[J]. 电网技术, 2021, 43(9):3297-3305.
ZHANG Y, JING L, WU X Z, et al.A novel DC autotransformer applied to DC grids[J]. Power system technology, 2021, 43(9): 3297-3305.
[9] 陈铮, 陈武, 刘忠, 等. 具有直流故障阻断能力的电流主动转移型MMC[J]. 电力系统自动化, 2021, 45(4): 106-114.
CHEN Z, CHEN W, LIU Z, et al.Active current-transferring modular multilevel converter with DC fault blocking capability[J]. Automation of electric power systems, 2021, 45(4): 106-114.
[10] 李梦柏, 向往, 左文平, 等. 具备无闭锁穿越直流故障能力的直流自耦变压器[J]. 电力系统自动化, 2018, 42(4): 82-88.
LI M B, XIANG W, ZUO W P, et al.DC-DC autotransformers with uninterrupted operating capability during DC fault[J]. Automation of electric power systems, 2018, 42(4): 82-88.
[11] 陈阳, 王晗, 朱淼, 等. 基于开关电容二端口子模块的自耦式模块化直流变压器[J]. 高电压技术, 2021, 47(7): 2457-2470.
CHEN Y, WHANG H, ZHU M, et al.Modular DC auto-transformer with two-port switched-capacitor submodules[J]. High voltage engineering, 2021, 47(7): 2457-2470.
[12] 林卫星, 文劲宇, 程时杰. 多端口直流-直流自耦变压器[J]. 中国电机工程学报, 2015, 35(3): 727-734.
LIN W X, WEN J Y, CHENG S J.Multiport DC-DC autotransformer[J]. Proceedings of the CSEE, 2015, 35(3): 727-734.
[13] ZHANG X T, GREEN T C.The modular multilevel converter for high step-up ratio DC-DC conversion[J]. IEEE transactions on industrial electronics, 2015, 62(8): 4925-4936.
[14] PANDEY R, SAHU L K, CHACKO S T.Self-balanced modular multilevel DC-DC converter for high conversion ratio[C]//2020 First International Conference on Power, Control and Computing Technologies(ICPC2T),Raipur, India, 2020.
[15] CARDIEL-ALVAREZ M A, ARNALTES S, RODRIGUEZ-AMENEDO J L, et al. Decentralized control of offshore wind farms connected to diode-based HVDC links[J]. IEEE transactions on energy conversion, 2018, 33(3): 1233-1241.
[16] 曹文远, 韩民晓, 谢文强, 等. 交直流配电网逆变器并联控制技术研究现状分析[J]. 电工技术学报, 2019, 34(20): 4226-4241.
CAO W Y, HAN M X, XIE W Q, et al.Analysis on research status of parallel inverters control technologies for AC/DC distribution network[J]. Transactions of China Electrotechnical Society, 2019, 34(20): 4226-4241.
[17] 刘芳, 邓金鑫, 张杰, 等. 大功率高升压比光伏直流变压器控制策略[J]. 电力电子技术, 2019, 53(5): 45-48.
LIU F, DENG J X, ZHANG J, et al.Control strategy of high-power high-step-up ratio photovoltaic direct current transformer[J]. Power electronics, 2019, 53(5): 45-48.
[18] 张杰. 大功率高升压比光伏直流变压器控制策略研究[D]. 合肥: 合肥工业大学, 2019.
ZHANG J.Research on control strategy of high-power high-step-up ratio photovoltaic DC transformer[D]. Hefei: Hefei University of Technology, 2019.
[19] 刘芳, 张喆, 马铭遥, 等. 弱电网条件下基于稳定域和谐波交互的并网逆变器LCL参数设计[J]. 中国电机工程学报, 2019, 39(14): 4231-4242.
LIU F, ZHANG Z, MA M Y, et al.LCL filter design method based on stability region and harmonic interaction for grid-connected inverters in weak grid[J]. Proceedings of the CSEE, 2019, 39(14): 4231-4242.
[20] NAWAWI A, TONG C F, SHAN Y, et al.Design and demonstration of high power density inverter for aircraft applications[J]. IEEE transactions on industry applications, 2017, 53(2): 1168-1176.
[21] 刘芳. LCL-VSR的控制与设计[D]. 合肥: 合肥工业大学, 2008.
LIU F.Control and design of LCL-VSR[D]. Hefei:Hefei University of Technology, 2008.