摘要
针对含分布式电源(DG)的接入会使传统的前推回代法失效的问题,对DG并网后的前推回代法进行了改进。由于传统的无功初值取值方法与实际值偏差较大,使迭代次数增加,本算法基于无功分摊原理确定PV型DG的无功初值,改进了无功修正值的求法。传统的前推回代法不能处理PV型节点,因此需要把PV节点转换为PQ节点进行求解,给出了无功修正量与节点的电压偏差和节点电抗的关系。结果表明:对于PV恒定型DG单独并网时的潮流,PV型DG从1～3台并网计算中,分别迭代到5、7、7次收敛,收敛次数增加小于2次,迭代时间增加少于0.01s;同时给出了PQ型和PI型DG单独、混合并网时的计算结果,各方案的迭代次数小于10次,时间增加小于0.01s,说明本算法对解决PQ、PI和PV节点单独、混合接入DG的潮流计算问题的正确性。
To solve the invalidity of traditional forward and backward substitution in distributed generation（DG） case,an improved forward and backward substitution method is proposed.Large deviation between the reactive initial value from the traditional method and the actual value leads to increasing iterations,so reactive power allocation theory is considered to determine the reactive initial value,and to improve the algorithm for modified reactive value.The traditional forward and backward substitution is unable to deal with PV-type nodes,they have to be converted to PQ nodes to solve.The relationship of reactive power revised value with voltage deviation of nodes and node reactance is obtained.The simulation indicates that for load flow of single invariable PV-type DG connecting to grid,the convergence needs 5,7 and 7 iterations respectively for one to three PV-type DG grid.The increase of iteration number is less than 2 and the increased iteration period is less than 0.01 s to verify the reasonableness of the algorithm.For PQ-type and PI-type DG separate grid or mixing grid,the iterations of all options are less than 10,and increased period is less than 0.01 s.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2013年第6期117-123,共7页
Journal of Xi'an Jiaotong University
基金
中国博士后科学基金资助项目(20090460863)
黑龙江省自然科学基金资助项目(E201260)
黑龙江省教育厅科学技术研究资助项目(12511003)
关键词
分布式电源
潮流计算
前推回代
distributed generation
load flow calculation
backward and forward
