电工技术学报2024,Vol.39Issue(20):6462-6474,13.DOI:10.19595/j.cnki.1000-6753.tces.231341
基于基准频率自适应谐波准谐振控制器的宽变频逆变电源控制研究
Research on Control of Wideband Variable-Frequency Inverters Based on Harmonics Quasi Resonant Controller with Frequency Reference Adapting
摘要
Abstract
With the development of more electric aircraft(MEA)and the increase of aircraft power system capability,AC power system of 360~800 Hz wide variable frequency has become one of the most important development trends due to its high reliability,high power density,and huge individual machine capability.However,since more and more electric and electronic equipment,especially nonlinear loads such as rectifiers,are applied in aircraft,the harmonics induced by those loads significantly impact the voltage quality of the aircraft grid.Unlike a 50 Hz inverter,the harmonic frequency of a medium-frequency inverter is very high,usually beyond the control band,which leads to a relatively small phase margin and great difficulty in control.Typical methods,such as repetitive control,do not satisfy the requirement when the power source frequency varies.QPR(quasi-proportional resonant)and HQR(harmonics quasi-resonant)control performs poor stability since its phase changes suddenly at the resonant frequency. The paper focuses on harmonics suppression for 360~800 Hz wide variable frequency AC power inverter,as well as the stability of the voltage controller.First,the structure of a single-phase inverter with digital control is described,and then the delay of digital control,which greatly influences control stability,is derived.Next,the stability of the control system with the application of HQR is discussed.The system phase margin is very small,even negative.Due to large frequency variation,a constant angle compensation cannot ensure the control system's stability.To simplify the design of the voltage controller,inductor current feedback active damping with digital control delay compensation is designed,which provides a suitable stability margin and minimum phase characteristic for the controlled object and suppresses the resonance peak.Furthermore,the I(integration)+QPR control scheme is proposed to improve the tracking ability of fundamental voltage. As the frequency varies from 360 Hz to 800 Hz,for HQR,a constant angle compensation cannot guarantee the voltage controller's stability.Accordingly,a frequency self-adapted HQR-PC(harmonics quasi-resonant with phase compensation)is proposed,compensating a specific angle for the control object to acquire a sufficient stability margin under a wide frequency reference range.After that,the stability of the control system is verified by root locus figures.The digital control implementation method of polynomial fitting of compensation angle is also given.It is indicated that the control scheme has high open-loop gain at fundamental and harmonics frequencies by open-loop frequency response,and harmonics can be suppressed with simulation verification. Finally,an experimental platform of 600 W medium frequency inverter power supply with a wide output frequency range is built.The control performance of the proposed control methods is tested with resistive and nonlinear loads,respectively.The results show that the medium-frequency inverter can output voltage with small harmonics,and the total harmonics distortion of the output voltage conforms to the industrial power supply standard under the frequency reference range.Moreover,the inverter shows excellent static and dynamic performance.关键词
变频逆变电源/谐波抑制/准谐振控制/相位补偿/自适应控制Key words
Variable-frequency inverters/harmonics suppression/quasi resonant control/phase com-pensation/adaptive control分类
信息技术与安全科学引用本文复制引用
刘海春,过仕安,钱强,谢少军..基于基准频率自适应谐波准谐振控制器的宽变频逆变电源控制研究[J].电工技术学报,2024,39(20):6462-6474,13.基金项目
国家自然科学基金资助项目(52277183). (52277183)