| 引用本文: | 聂川杰,熊飞,陈晓雷,邓钦元,严冬.基于能量回馈的电力电子变压器软启动策略[J].电力自动化设备,2022,42(12): |
| NIE Chuanjie,XIONG Fei,CHEN Xiaolei,DENG Qinyuan,YAN Dong.Soft start strategy of power electronic transformer based on energy feedback[J].Electric Power Automation Equipment,2022,42(12): |
|
| 摘要: |
| 电力电子变压器(PET)中存在大量初始能量为0的电容器，若直接启动PET通过常规闭环控制给这些电容充电以建立直流电压，则将导致PET内部各个变换器的电流过流，可能会导致器件的损坏。为解决此问题，提出了一种基于能量回馈的PET软启动策略。基于PET各部分变换器的电流和功率模型，该策略能够在软启动全过程中实时计算和控制峰值电流，达到了限制启动冲击电流的目的。该策略始终令双有源桥(DAB)变换器工作于峰值电流控制模式下，在保证安全的前提下最大化利用DAB变换器的功率传输能力以加快软启动速度。该策略将低压直流母线电容适度过充，并适时将其中部分能量回馈到高压侧，使得在级联H桥变换器即将进入闭环控制前其高压直流母线电压就已达到参考值，从而彻底消除交流侧的冲击电流。所提策略避免了复杂的参数设计过程，完全依靠理论模型而不是经验来指导软启动全过程的设计。仿真与实验结果验证了所提策略的正确性和有效性。 |
| 关键词: 电力电子变压器 级联H桥变换器 双有源桥变换器 软启动 能量回馈 |
| DOI：10.16081/j.epae.202204066 |
| 分类号:TM46 |
| 基金项目:重庆市教育委员会科学技术研究项目(KJQN202000620) |
|
| Soft start strategy of power electronic transformer based on energy feedback |
|
NIE Chuanjie, XIONG Fei, CHEN Xiaolei, DENG Qinyuan, YAN Dong
|
|
College of Automation, Chongqing University of Posts & Telecommunications, Chongqing 400065, China
|
| Abstract: |
| There are a large number of capacitors with zero initial energy in PET(Power Electronic Transformer). If starting PET directly to charge these capacitors through conventional closed-loop control and establish DC voltage, it will lead to the current of each converter inside PET overflow, which may cause device damage. To solve this problem, a soft start strategy for PET based on energy feedback is presented. Based on the current and power model of each part of PET converter, this strategy can calculate and control the peak current in real time during the whole soft start process, and achieve the purpose of limiting the start-up inrush current. This strategy keeps the DAB(Dual Active Bridge) converter operating in peak current control mode and maximizes the power transfer capacity of DAB converter to speed up the soft start while ensuring security. This strategy moderately overcharges the DC bus capacitor on the low voltage side and feeds some of its energy back to the high voltage side in time, so that the DC bus voltage on the high voltage side reaches the reference value just before the CHB(Cascaded H-Bridge) converter enters the closed-loop control, thus eliminating the inrush current of AC side completely. The proposed strategy avoids the complex parameter design process, and completely relies on the theoretical model rather than experience to guide the design of the whole soft start process. The simulative and experimental results verify the correctness and effectiveness of the proposed strategy. |
| Key words: power electronic transformer cascaded H-bridge converter dual active bridge converter soft start energy feedback |
