中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2013年
21期
53-62
,共10页
模块化多电平换流器%高电压直流输电%比例谐振控制器%正负序%电容电压均衡
模塊化多電平換流器%高電壓直流輸電%比例諧振控製器%正負序%電容電壓均衡
모괴화다전평환류기%고전압직류수전%비례해진공제기%정부서%전용전압균형
modular multilevel converter (MMC)%high voltage direct current (HVDC) transmission system%proportional-resonant (PR) controller%positive and negative series%capacitance voltage balance
基于模块化多电平高压直流输电系统(high voltage direct current transmission based on modular multilevel converter，MMC-HVDC)通常采用双闭环矢量控制策略，由于该策略在不平衡故障情况下，需要采用正负序2套旋转坐标系对正负序电流分别进行控制，从而存在需要调整控制参数多、动态响应慢的问题。该文在两相静止αβ坐标系下，分析了 MMC-HVDC 数学模型的特点，并对其功率分量进行了相应推导。为了实现交流信号无静差控制，在αβ坐标系下引入比例谐振控制器实现正负序电流的统一控制，该策略无需繁琐的旋转坐标变换，从而不存在受电路参数影响的耦合项和前馈补偿项，进而方便了控制器的设计；同时利用PR控制器对传统电容电压均衡控制内环进行了改进，最后，在PSCAD/EMTDC中搭建的仿真模型基础上，验证了αβ-PR平衡和不平衡控制策略的有效性。
基于模塊化多電平高壓直流輸電繫統(high voltage direct current transmission based on modular multilevel converter，MMC-HVDC)通常採用雙閉環矢量控製策略，由于該策略在不平衡故障情況下，需要採用正負序2套鏇轉坐標繫對正負序電流分彆進行控製，從而存在需要調整控製參數多、動態響應慢的問題。該文在兩相靜止αβ坐標繫下，分析瞭 MMC-HVDC 數學模型的特點，併對其功率分量進行瞭相應推導。為瞭實現交流信號無靜差控製，在αβ坐標繫下引入比例諧振控製器實現正負序電流的統一控製，該策略無需繁瑣的鏇轉坐標變換，從而不存在受電路參數影響的耦閤項和前饋補償項，進而方便瞭控製器的設計；同時利用PR控製器對傳統電容電壓均衡控製內環進行瞭改進，最後，在PSCAD/EMTDC中搭建的倣真模型基礎上，驗證瞭αβ-PR平衡和不平衡控製策略的有效性。
기우모괴화다전평고압직류수전계통(high voltage direct current transmission based on modular multilevel converter，MMC-HVDC)통상채용쌍폐배시량공제책략，유우해책략재불평형고장정황하，수요채용정부서2투선전좌표계대정부서전류분별진행공제，종이존재수요조정공제삼수다、동태향응만적문제。해문재량상정지αβ좌표계하，분석료 MMC-HVDC 수학모형적특점，병대기공솔분량진행료상응추도。위료실현교류신호무정차공제，재αβ좌표계하인입비례해진공제기실현정부서전류적통일공제，해책략무수번쇄적선전좌표변환，종이불존재수전로삼수영향적우합항화전궤보상항，진이방편료공제기적설계；동시이용PR공제기대전통전용전압균형공제내배진행료개진，최후，재PSCAD/EMTDC중탑건적방진모형기출상，험증료αβ-PR평형화불평형공제책략적유효성。
The high voltage direct current transmission based on modular multilevel converter (MMC-HVDC) usually adopts double closed-loop vector control, which has the problems such as too many parameters needed to be adjusted and dynamic response being unsatisfied under voltage unbalanced condition in order to control the positive and negative current in positive and negative rotating reference frame. This paper analyzes the MMC-HVDC’s mathematic characteristics under αβ reference frame, what is more, the power calculation is also conducted. In order to reduce the sin ac signal zero error and control the positive and negative current uniformly, the proportional-resonant(PR)controller is introduced in αβ reference frame which does not need the complex reference transformation, so the disadvantageous effect of coupled or feedback voltage which is easily influenced by circuit parameters is eliminated, the control algorithm becomes easy to be realized; In addition, the traditional voltage balancing strategy is also improved through the PR. The simulation platform of MMC-HVDC is built in the electromagnetic transient simulation software PSCAD/ EMTDC, and the simulation of αβ-PR is carried out to verify this controllers’ effectiveness and feasibility.
