CAJ | 학술논문

针对直驱永磁同步发电机(PMSG)机侧变流器无功功率未知时,PMSG 稳态约束为不定方程组,需要补充边界条件才能得到唯一解的问题,文中建立了基于定子电流或定子电压定向约束的稳态求解算法。发现由于定向约束不能反映机侧无功平衡,两种定向下计算结果不一致。进一步考虑有功调度,在两种定向约束下分别采用转速调节或桨距角调节,建立 PMSG 稳态解算法。计算结果证实：定子电流定向时发电机有功损耗更小,机电能量转换效率更高,但是吸收无功功率更多；随风速增加,吸收无功功率增加,定子电流定向时发电机能量转换效率下降,定子电压定向时效率增加；转速偏离最优转速或增加桨距角,都可实现对PMSG的有功调度,但机电能量转换效率不同,采用桨距角调节时,收敛速度快于转速调节。
침대직구영자동보발전궤(PMSG)궤측변류기무공공솔미지시,PMSG 은태약속위불정방정조,수요보충변계조건재능득도유일해적문제,문중건립료기우정자전류혹정자전압정향약속적은태구해산법。발현유우정향약속불능반영궤측무공평형,량충정향하계산결과불일치。진일보고필유공조도,재량충정향약속하분별채용전속조절혹장거각조절,건립 PMSG 은태해산법。계산결과증실：정자전류정향시발전궤유공손모경소,궤전능량전환효솔경고,단시흡수무공공솔경다；수풍속증가,흡수무공공솔증가,정자전류정향시발전궤능량전환효솔하강,정자전압정향시효솔증가；전속편리최우전속혹증가장거각,도가실현대PMSG적유공조도,단궤전능량전환효솔불동,채용장거각조절시,수렴속도쾌우전속조절。
In view of the need of a boundary condition to obtain the unique solution for the steady-state constraints of permanent magnet synchronous generators (PMSGs) that are a set of indeterminate equations with the reactive power output of the machine-side converter unfixed,steady-state solutions based on the stator current/voltage orientations are proposed.Because of inconsistency with the reactive power balance of the machine-side-converter,the solutions under two orientations are different. Further consideration of the power dispatch by adj usting the rotor speed or the pitch angle,steady-state solutions to PMSG are proposed.The numerical results show that:(1) the stator current orientation yields less active loss and higher efficiency,but absorbs more reactive power;(2)with increased wind speed,the PMSG absorbs more reactive power,the efficiency decreases with stator current orientation,but increases with stator voltage orientation;(3) active power dispatch may be realized by changing the rotor speed or the pitch angle,while the efficiency is different,and adj usting the pitch angle yields better convergence than adj usting the rotor speed.