| 引用本文: | 程 静,赵振民.基于虚拟同步发电机的固态变压器交流端口柔性控制策略研究[J].电力系统保护与控制,2023,51(4):138-147.[点击复制] |
| CHENG Jing,ZHAO Zhenmin.Flexible control strategy for a solid-state transformer AC port based on a virtual synchronous generator[J].Power System Protection and Control,2023,51(4):138-147[点击复制] |
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| 摘要: |
| 固态变压器(solid state transformer, SST)能实现传统电力变压器的变压、隔离作用，还可实现灵活的电能调控作用，但不具备传统同步发电机的机械特性及同步运行机制。当分布式电源经SST接入电网时，由于其出力的随机性和波动性，将对上级电网造成冲击，导致电网电压/频率波动。提出一种基于虚拟同步发电机的SST交流端口控制策略。首先，建立模块化多电平型输入级和同步发电机等效模型，将虚拟同步发电机原理融入输入级控制策略，以提高SST并网端口的电能质量、惯性及阻尼特性，并使其具备参与电网调频、调压能力。其次，提出储能装置辅助调频控制，保障SST参与一次调频时低压系统负载功率消耗平衡。最后，确立了输出级虚拟同步发电机控制策略，以提高低压交流端口负荷功率响应特性，实现SST对上级电网的友好性。在Matlab/Simulink平台搭建仿真模型，验证了所提SST拓扑结构及其控制策略的正确性和有效性。 |
| 关键词: 虚拟同步发电机 固态变压器 分布式电源 模块化多电平变换器 控制策略 |
| DOI：10.19783/j.cnki.pspc.220680 |
| 投稿时间：2022-05-09修订日期：2022-07-13 |
| 基金项目:新疆维吾尔自治区重大科技专项资助(2022A01001-4)；新疆维吾尔自治区重点实验室开放课题(2020D04048)；国家自然科学基金项目资助(52067020) |
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| Flexible control strategy for a solid-state transformer AC port based on a virtual synchronous generator |
| CHENG Jing1,ZHAO Zhenmin1，2 |
| (1. Engineering Research Center of Education Ministry for Renewable Energy Power Generation and Grid Connection,
Xinjiang University, Urumqi 830017, China; 2. Electric Power Research Institute of State Grid Xinjiang
Electric Power Co., Ltd., Urumqi 830011, China) |
| Abstract: |
| A solid-state transformer (SST) can realize the voltage transformation and isolation of a traditional power transformer and flexible power regulation, but it does not have the mechanical characteristics and synchronous operation mechanism of a traditional synchronous generator. When distributed power generation is connected to the power grid through the SST, because of the randomness and power fluctuation of distributed power generation, it will impact the superior power grid and lead to grid voltage or frequency fluctuation. A control strategy for the SST AC port based on a virtual synchronous generator is proposed. First, the equivalent model of the modular multilevel input stage and synchronous generator is established, and the principle of the virtual synchronous generator is integrated into the input stage control strategy to improve the power quality, inertia, and damping characteristics of the SST grid connection port. It also gives it the ability to participate in power grid frequency regulation and voltage regulation. Second, auxiliary frequency modulation control of the energy storage device is proposed to ensure the balance of load power consumption of the low-voltage system when the SST participates in primary frequency modulation. Finally, the control strategy of output stage of the virtual synchronous generator is established to improve the load power response characteristics of the low-voltage AC port and realize the ‘friendliness’ of the SST to the superior power grid. The simulation model is established on the Matlab/Simulink platform to verify the correctness and effectiveness of the proposed SST topology and its control strategy.
This work is supported by Major Science and Technology Project of the Xinjiang Uygur Autonomous Region (No. 2022A01001-4). |
| Key words: virtual synchronous generator solid state transformer distributed generation modular multilevel converter control strategy |
