Cooperative Control Strategy Based on FPGA Real-time Simulation for PV-ESS Independent DC Microgrid

doi:10.12204/j.issn.1000-7229.2023.04.011

Abstract

Abstract:

Field programmable gate array (FPGA) has the advantages of high data parallelism and high operating frequency, which can meet the needs of micro-second step precision simulation of power system, and shows great potential in the real-time simulation of the microgrid. For the further study of dynamic characteristics of photovoltaic (PV) and energy storage system (ESS) in the microgrid, the real-time simulation system of independent PV-ESS low-voltage DC microgrid is designed based on FPGA. Firstly, the real-time simulation framework of the DC microgrid is built, and a series of typical modules of the electrical system is designed. Secondly, considering the different dynamic requirements of real-time simulation, the PV-ESS control system model covering a variety of control strategies is built. Then, a hierarchical coordinated control strategy based on DC bus Signaling (DBS) is proposed, which balances the energy flow of the system by coordinating the control strategy of the PV-ESS converter. Finally, the FPGA real-time simulation results are compared with Simulink software. On the one hand, the accuracy and reliability of the FPGA real-time simulator are verified. On the other hand, it is also verified that the hierarchical coordination control strategy can smoothly switch the working layer, balance the power flow of the system, and effectively maintain the voltage stability of the DC bus.

Key words: low-voltage DC microgrid, photovoltaic, energy storage system, field programmable gate array (FPGA), hierarchical coordination control, real-time simulation

CLC Number:

TM743

WANG Shouxiang, HE Ruxun, ZHANG Chunyu, ZHAO Qianyu. Cooperative Control Strategy Based on FPGA Real-time Simulation for PV-ESS Independent DC Microgrid[J]. ELECTRIC POWER CONSTRUCTION, 2023, 44(4): 94-102.

Figures/Tables 16

Fig.1 Framework of node analysis method based on FPGA

Fig.2 Sequence generator based on finite state machine

Fig.3 Inductance solving model based on FPGA

Fig.4 Equivalent circuit model of battery

Fig.5 Battery model solution based on FPGA

Fig.6 Photovoltaic power solution model based on FPGA

Fig.7 MPPT solution model based on FPGA

Fig.8 Constant-voltage discharge strategy for battery

Fig.9 Solution model of battery constant-voltage discharge control strategy based on FPGA

Fig.10 Hierarchical cooperative control strategy for PV-ESS independent DC microgrid

Table 1 Logic judgment of photovoltaic cell working mode

Table 2 Logic judgment of battery working mode

Fig.11 Solution model based on FPGA for hierarchical cooperative control

Fig.12 Output power of PV module

Fig.13 Charge-discharge power of battery

Fig.14 Voltage curve of DC bus

References 20

[1]	DAGBAGI M, HEMDANI A, IDKHAJINE L, et al. ADC-based embedded real-time simulator of a power converter implemented in a low-cost FPGA: application to a fault-tolerant control of a grid-connected voltage-source rectifier[J]. IEEE Transactions on Industrial Electronics, 2016, 63(2): 1179-1190. doi: 10.1109/TIE.2015.2491883 URL
[2]	徐晋, 汪可友, 李国杰. 电力电子设备及含电力电子设备电力系统实时仿真研究综述[J]. 电力系统自动化, 2022, 46(10): 3-17.
	XU Jin, WANG Keyou, LI Guojie. Review of real-time simulation of power electronic devices and power systems integrated with power electronic devices[J]. Automation of Electric Power Systems, 2022, 46(10): 3-17.
[3]	CHEN Y, DINAVAHI V. An iterative real-time nonlinear electromagnetic transient solver on FPGA[J]. IEEE Transactions on Industrial Electronics, 2011, 58(6): 2547-2555. doi: 10.1109/TIE.2010.2060461 URL
[4]	吴志勇, 王晞阳, 陈继林. 一种基于FPGA并行加速的稀疏矩阵求解方法[J]. 电力系统保护与控制, 2021, 49(11): 155-162.
	WU Zhiyong, WANG Xiyang, CHEN Jilin. A method for solving a sparse matrix based on FPGA parallel acceleration[J]. Power System Protection and Control, 2021, 49(11): 155-162.
[5]	王成山, 丁承第, 李鹏, 等. 基于FPGA的配电网暂态实时仿真研究(一): 功能模块实现[J]. 中国电机工程学报, 2014, 34(1): 161-167.
	WANG Chengshan, DING Chengdi, LI Peng, et al. Real-time transient simulation for distribution systems based on FPGA, part I: module realization[J]. Proceedings of the CSEE, 2014, 34(1): 161-167.
[6]	WANG Z Y, ZENG F P, LI P, et al. Kernel solver design of FPGA-based real-time simulator for active distribution networks[J]. IEEE Access, 2018, 6: 29146-29157. doi: 10.1109/ACCESS.2018.2842076 URL
[7]	王成山, 丁承第, 李鹏, 等. 基于FPGA的配电网暂态实时仿真研究(二): 系统架构与算例验证[J]. 中国电机工程学报, 2014, 34(4): 628-634.
	WANG Chengshan, DING Chengdi, LI Peng, et al. Real-time transient simulation for distribution systems based on FPGA, part Ⅱ: system architecture and algorithm verification[J]. Proceedings of the CSEE, 2014, 34(4): 628-634.
[8]	王成山, 丁承第, 李鹏, 等. 基于FPGA的光伏发电系统暂态实时仿真[J]. 电力系统自动化, 2015, 39(12): 13-20.
	WANG Chengshan, DING Chengdi, LI Peng, et al. FPGA-based real-time transient simulation of photovoltaic generation system[J]. Automation of Electric Power Systems, 2015, 39(12): 13-20.
[9]	丁承第, 李鹏, 王成山, 等. 基于现场可编程门阵列的分布式发电系统实时仿真相关问题研究[J]. 电网技术, 2016, 40(7): 2022-2029.
	DING Chengdi, LI Peng, WANG Chengshan, et al. Research on related issues of real-time simulation for distributed generation system based on FPGA[J]. Power System Technology, 2016, 40(7): 2022-2029.
[10]	朱建鑫, 滕国栋, 秦阳, 等. 基于多FPGA的电力电子实时仿真系统[J]. 电力系统自动化, 2017, 41(9): 137-143.
	ZHU Jianxin, TENG Guodong, QIN Yang, et al. Multi-FPGA based real-time simulation system for power electronics[J]. Automation of Electric Power Systems, 2017, 41(9): 137-143.
[11]	MILTON M, BENIGNI A, MONTI A. Real-time multi-FPGA simulation of energy conversion systems[J]. IEEE Transactions on Energy Conversion, 2019, 34(4): 2198-2208. doi: 10.1109/TEC.60 URL
[12]	王子鹏, 郑丽君, 吕世轩. 考虑多储能系统功率分配的独立直流微电网协调控制策略[J]. 电力建设, 2021, 42(4): 89-96. doi: 10.12204/j.issn.1000-7229.2021.04.010 URL
	WANG Zipeng, ZHENG Lijun, LÜ Shixuan. Coordinated control for islanded DC microgrid considering power sharing of multiple energy storages[J]. Electric Power Construction, 2021, 42(4): 89-96. doi: 10.12204/j.issn.1000-7229.2021.04.010 URL
[13]	米阳, 吴彦伟, 符杨, 等. 独立光储直流微电网分层协调控制[J]. 电力系统保护与控制, 2017, 45(8): 37-45.
	MI Yang, WU Yanwei, FU Yang, et al. Hierarchical coordinated control of island DC microgrid with photovoltaic and storage system[J]. Power System Protection and Control, 2017, 45(8): 37-45.
[14]	ZHANG Y, JIA H J, GUO L. Energy management strategy of islanded microgrid based on power flow control[C]// 2012 IEEE PES Innovative Smart Grid Technologies (ISGT). January 16-20, 2012, Washington, DC, USA. IEEE, 2012: 1-8.
[15]	王植, 马振, 胡鹏涛, 等. 孤岛交直流混合微电网功率互助策略[J]. 电力建设, 2021, 42(1): 76-84. doi: 10.12204/j.issn.1000-7229.2021.01.009 URL
	WANG Zhi, MA Zhen, HU Pengtao, et al. Mutual power support strategy for isolated hybrid AC/DC microgrid[J]. Electric Power Construction, 2021, 42(1): 76-84. doi: 10.12204/j.issn.1000-7229.2021.01.009 URL
[16]	陈景文, 周媛, 李晓飞, 等. 光储直流微网混合储能控制策略研究[J]. 智慧电力, 2022, 50(1): 14-20, 87.
	CHEN Jingwen, ZHOU Yuan, LI Xiaofei, et al. Hybrid energy storage control strategy of optical storage DC microgrid[J]. Smart Power, 2022, 50(1): 14-20, 87.
[17]	TREMBLAY O, DESSAINT L A, DEKKICHE A I. A generic battery model for the dynamic simulation of hybrid electric vehicles[C]// 2007 IEEE Vehicle Power and Propulsion Conference. September 9-12, 2007, Arlington, TX, USA. IEEE, 2008: 284-289.
[18]	陈亚爱, 周京华, 李津, 等. 梯度式变步长MPPT算法在光伏系统中的应用[J]. 中国电机工程学报, 2014, 34(19): 3156-3161.
	CHEN Yaai, ZHOU Jinghua, LI Jin, et al. Application of gradient variable step size MPPT algorithm in photovoltaic system[J]. Proceedings of the CSEE, 2014, 34(19): 3156-3161.
[19]	LI Z J, ZHANG Y N, WANG L J, et al. Study of photovoltaic multimodal maximum power point tracking baced on improved quantum particle swarm optimization[J]. Acta Energiae Solaris Sinica, 2021, 42(5):221-229.
[20]	隋春杰. 光储直流微电网中基于SOC的下垂控制策略研究[D]. 曲阜: 曲阜师范大学, 2021.
	SUI Chunjie. Research on sag control strategy based on SOC in optical storage DC microgrid[D]. Qufu: Qufu Normal University, 2021.