无交流电压传感器并网逆变器的控制策略及其改进  

Control strategy of grid-connected converter without AC voltage sensor and its improvement

作　　者：吴凤江[1,2] 孙秀冬[1] 孙力[2] 赵克[2] 

机构地区：[1]哈尔滨工业大学物理系,黑龙江哈尔滨150001 [2]哈尔滨工业大学电气工程系,黑龙江哈尔滨150001

出　　处：《电力自动化设备》2009年第7期33-37,共5页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(50477009)~~

摘　　要：将基于虚拟磁链的直接功率控制策略用于并网逆变器的控制。详细推导了虚拟磁链与瞬时功率的表达式,在无需检测网侧交流电压的前提下即可获得并网功率的瞬时值,进而取消了交流电压传感器。通过对并网功率的有功和无功成分进行直接独立控制,省去了旋转坐标变换以及电流闭环控制等复杂算法。采用带有饱和限幅反馈环节的积分器代替不定积分器进行虚拟磁链观测,解决了因传统观测方法存在功率计算偏差而造成系统效率降低、动态响应性能较差等问题。对所提出的改进观测方法及基于改进虚拟磁链直接功率控制策略的并网逆变器进行仿真和实验,结果证明了所提方法的正确性和可行性。The DPC （Direct Power Control） strategy based on VF（Virtual Flux- linkage） is applied to grid -connected converter. The functions between VF and instantaneous power are derived. As the instantaneous powers can be obtained without grid- side voltage detection,the AC voltage sensors are avoided. By independent controlling the active and reactive components of parallel- in power,the complex algorithms, including the rotation coordinates conversion and the closed-loop current control,are abbreviated. Instead of the pure integrator,the integrator with saturation limit feedback is applied in the virtual flux-linkage observer to avoid the power calculation error of conventional methods,which causes low system efficiency and worse dynamic performance. Simulative and experimental results prove the correctness and feasibility of the proposed method.

关 键 词：并网逆变器 直接功率控制 虚拟磁链 积分器 改进 

分 类 号：TM464[电气工程—电器]