| 引用本文: | 肖丽平,吕 超,和青芳,程 光.基于最优占空比原则的脉频调制策略的应用[J].电力系统保护与控制,2022,50(15):158-167.[点击复制] |
| XIAO Liping,LÜ Chao,HE Qingfang,CHENG Guang.Application of PFM strategy based on the principle of optimal duty cycle[J].Power System Protection and Control,2022,50(15):158-167[点击复制] |
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| 摘要: |
| 传统的开关器件脉频调制(Pulse Frequency Modulation, PFM)控制方法，存在开关频率高、频率不固定且稳定性能不好的缺点，使得它在APF的应用中增加了滤波器的设计难度。为此提出了以最优占空比为原则的改进脉频调制方法。该方法通过最小二乘法获得最优占空比，并依此合理选择控制参数，且在控制器中，引入电网及补偿电压的实时特性，参与开关器件的导通时间、关断时间及滞环环宽的控制，从而实现定频、降损、提高控制精度及动态性能。通过对PFM的传统与改进控制策略的仿真与实验，验证了所提方法的有效性，且该方法易于控制电路的设计。 |
| 关键词: 脉频调制 滞环电流控制 COT控制 CFT控制 最优占空比 |
| DOI：DOI: 10.19783/j.cnki.pspc.211720 |
| 投稿时间：2021-12-16修订日期：2022-04-05 |
| 基金项目:国家自然科学基金项目资助(61871028)；北京市自然科学基金-丰台轨道交通前沿研究联合基金(L191006)；北京联合大学校级科研项目资助(ZK202205) |
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| Application of PFM strategy based on the principle of optimal duty cycle |
| XIAO Liping,LÜ Chao,HE Qingfang,CHENG Guang |
| (1. Frontier Intelligent Technology Research Institute, Beijing Union University, Beijing 100101, China;
2. School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin 150001, China) |
| Abstract: |
| In traditional control methods of pulse frequency modulation (PFM) there exists a high and variable switching frequency, and stability is poor. The challenge of filter design is multiplied when they are used in APF. Therefore, an improved PFM method based on the principle of an optimal duty cycle is proposed. The optimal duty cycle is obtained by the least squares method. From this, reasonable control parameters are selected. Real-time characteristics of power grid and compensation voltages are introduced into the controller to control the on-time, off-time and hysteresis loop width of the switching device, so as to achieve constant frequency, reduce switching loss, improve control accuracy and dynamic performance. Simulation and experiment of the traditional and the improved methods of PFM verify the effectiveness of the proposed method, and it is easy to design the control circuit with this method.
This work is supported by the National Natural Science Foundation of China (No. 61871028). |
| Key words: pulse frequency modulation hysteresis current control COT control CFT control optimal duty cycle |
