电工技术学报2026，Vol.41Issue(2)：591-606,16.DOI:10.19595/j.cnki.1000-6753.tces.250087
考虑机组起动转矩特性的抽水蓄能电站非特征谐波产生机理分析
Non-Characteristic Harmonic Generation Mechanism of Pumped Storage Power Station Unit Considering Starting Torque Characteristics
摘要
Abstract
The SFC,as the core equipment for the startup control of pumped storage power plant units,emits many harmonics to the power supply side during the acceleration of the units to their rated speeds.As more cable feeders are linked to the plant bus,the issue of harmonic pollution from non-characteristic harmonics on the plant power system becomes increasingly visible.This paper examines the impact of REC trigger angle fluctuations and intermittent phase changes in the inverter(INV).An accurate calculation model of the AC side current of REC is developed to quantitatively analyze the spectral distribution of harmonic currents on the power side of the SFC. Firstly,the concept of harmonic torque is introduced to decompose the electromagnetic torque at the high and low speed stages of the motor startup into the superposition of a constant torque and a harmonic torque.Secondly,the motor speed fluctuation component generated by the harmonic torque is obtained through the motor rotor equation of motion.Then,the transfer function in the control system with the rotational speed fluctuation component as the input and the trigger angle fluctuation component as the output is derived.The time-domain expression for the trigger angle fluctuation of the REC can be obtained.Finally,the trigger angle fluctuation is brought into the expression of the REC AC side current to establish an accurate calculation model of the REC AC side current in one cycle,and the frequency and amplitude of the trigger angle fluctuation are analyzed to determine the influence of the trigger angle fluctuation on the REC non-characteristic harmonics through the FFT. Under varying trigger angle fluctuation signals,non-characteristic harmonics manifest as sideband harmonics adjacent to the fundamental frequency and the characteristic harmonic frequencies at 6k±1.The frequency offsets of these non-characteristic harmonics correspond to the frequency of the trigger angle perturbation or the remainder obtained after division by the fundamental frequency.When the trigger angle perturbation comprises a superposition of multiple sinusoidal signals with distinct frequencies,the resultant set of non-characteristic harmonic frequencies is a composite of the individual sets produced by each single-frequency perturbation.Simulation results indicate that during the low-speed phase,an intermittent phase change causes the REC trigger angle to shift abruptly from a steady state of 83° to 150°.The trigger angle experiences a sudden transition from 150° to 21°,resulting in significant fluctuations.Conversely,during the high-speed phase,the REC trigger angle exhibits stable fluctuations between 68° and 72°,with an amplitude of no more than 3°,indicating a relatively minor fluctuation.Correspondingly,the THD of the harmonic current on the AC side of the REC is recorded at 43.70％during the low-speed phase and 31.57％during the high-speed phase.Specifically,the contributions of the 5th,7th,11th,and 13th harmonic currents are 18.1％,8.9％,7.5％,and 5.0％ in the low-speed phase,and 20.7％,10.8％,6.9％,and 4.3％ in the high-speed phase. The following conclusions can be drawn.(1)The harmonic torque influences the SFC speed control system,producing a fluctuation component that matches the frequency of the harmonic torque in the trigger angle signal provided to the REC.(2)The non-characteristic harmonics of the REC are distributed as sideband harmonics surrounding the fundamental and characteristic harmonic frequency points,with their frequency distribution and emission intensity being contingent upon the fluctuation frequency and amplitude of the trigger angle.(3)During the low-speed phase of the pump turbine's frequency conversion startup,the non-characteristic harmonics introduced by the SFC to the power supply side are characterized by a concentration in the low-frequency band and a high emission intensity,with peak RMS values approaching 100 A,and the spectral content predominantly concentrated within the 0～250 Hz range.关键词
静止变频器/非特征谐波/谐波转矩/谐波特性/谐波测试Key words
Stationary frequency converters/non-characteristic harmonic/harmonic torque/harmonic characteristics/harmonic testing分类
信息技术与安全科学引用本文复制引用
李仲龙,姜飞,郑鸿睿,汤昊,姚鹏..考虑机组起动转矩特性的抽水蓄能电站非特征谐波产生机理分析[J].电工技术学报,2026,41(2):591-606,16.基金项目
国家自然科学基金项目(52377166)和珠海市产学研合作项目(2320004002712)资助. （52377166）
