电网技术
電網技術
전망기술
Power System Technology
2015年
4期
932-938
,共7页
姚骏%杜红彪%周特%谭义
姚駿%杜紅彪%週特%譚義
요준%두홍표%주특%담의
微网%逆变器并联%改进下垂控制%电压精度%动态性能
微網%逆變器併聯%改進下垂控製%電壓精度%動態性能
미망%역변기병련%개진하수공제%전압정도%동태성능
micro-grid%inverters parallel operation%improved droop control%voltage precision%dynamic performance
逆变器并联系统采用有功?电压频率(P-f)和无功?电压幅值(Q-U)下垂控制方法实现功率均分时,由于采用固定下垂参数,输出电压精度与功率均分效果之间存在矛盾;同时负荷发生剧烈突变时易造成输出电流振荡,从而影响系统的稳定运行。此外,为获得稳定准确的系统功率输出,功率计算环节须引入低通滤波器,低通滤波器的延迟特性将会对系统的动态性能产生影响。为此,提出了一种改进的逆变器自适应下垂控制方法,该方法在传统控制方法基础上分别引入功率与下垂系数的一次函数项和功率与时间的微分项,既实现了下垂系数随功率变化的自适应调节,又及时反映出功率的变化趋势,有效提高了系统的稳定运行性能和动态响应能力。实验结果验证了所提方法的有效性。
逆變器併聯繫統採用有功?電壓頻率(P-f)和無功?電壓幅值(Q-U)下垂控製方法實現功率均分時,由于採用固定下垂參數,輸齣電壓精度與功率均分效果之間存在矛盾;同時負荷髮生劇烈突變時易造成輸齣電流振盪,從而影響繫統的穩定運行。此外,為穫得穩定準確的繫統功率輸齣,功率計算環節鬚引入低通濾波器,低通濾波器的延遲特性將會對繫統的動態性能產生影響。為此,提齣瞭一種改進的逆變器自適應下垂控製方法,該方法在傳統控製方法基礎上分彆引入功率與下垂繫數的一次函數項和功率與時間的微分項,既實現瞭下垂繫數隨功率變化的自適應調節,又及時反映齣功率的變化趨勢,有效提高瞭繫統的穩定運行性能和動態響應能力。實驗結果驗證瞭所提方法的有效性。
역변기병련계통채용유공?전압빈솔(P-f)화무공?전압폭치(Q-U)하수공제방법실현공솔균분시,유우채용고정하수삼수,수출전압정도여공솔균분효과지간존재모순;동시부하발생극렬돌변시역조성수출전류진탕,종이영향계통적은정운행。차외,위획득은정준학적계통공솔수출,공솔계산배절수인입저통려파기,저통려파기적연지특성장회대계통적동태성능산생영향。위차,제출료일충개진적역변기자괄응하수공제방법,해방법재전통공제방법기출상분별인입공솔여하수계수적일차함수항화공솔여시간적미분항,기실현료하수계수수공솔변화적자괄응조절,우급시반영출공솔적변화추세,유효제고료계통적은정운행성능화동태향응능력。실험결과험증료소제방법적유효성。
In the inverters parallel system which using the P-f andQ-U droop control method, the fixed droop coefficients are used to realize the power sharing, which will cause the contradiction between the output voltage precision and the power sharing effect. In addition, the output current oscillations caused by the loading variation could occur, which will decrease the stable operation performance of the whole system. Furthermore, the dynamics of the overall system are strongly influenced by the delaying characteristics of the low-pass filters which introduced to achieve the precise power calculation. To solve the problems mentioned above, an improved adaptive droop method is investigated for the control of the inverters. In the proposed method, a linear function of the power and droop coefficient is introduced to realize the adaptive regulation for the droop coefficients with the power variation, while a power derivative term is introduced to instantaneously reflect the trend of power, which effectively improving the stable operation performance and dynamic response capability. Finally, experimental results are used to validate the proposed droop control method.