Traditional power conditioning devices cannot continuously adjust transient power quality problems. Therefore, a Unified Power Quality Conditioner (UPQC) Continuously adjust power quality issues such as drops and harmonics. This article takes UPQC as the research object, introduces its basic structure and working principle, harmonic detection technology, tracking control technology, and determines the control strategy on both sides of the series and parallel connections; secondly, introduces the principle, advantages and disadvantages of PI control, and introduces this article The research content of Active Disturbance Rejection Control (ADRC) replaces PI control to maintain the voltage on the DC side of the UPQC. The principle and structure are introduced, the design method of linear ADRC is introduced in detail, the first-order linear active disturbance rejection controller adapted to the DC side of UPQC is built, and the simulation results are obtained.

Power quality adjustment; unified power quality modulator; PID control; auto-disturbance rejection control; robustness