Analysis And Compare Of Cascaded Structure And MMC Structure Of STATCOM

The rapid development of the power electronic technology and AC transmissiontechnology has become more mature. There have been various structures of theSTATCOM successfully developed and put into operation. As the field of domestictechnology leader, Tsinghua University has been successful completed the relevantproduct development and practical application coop rationed with major electricpower and power company. Among them, the35Kv,±200Mvar chain STATCOMhave already in Guangdong Dongguan Railway Station which research anddevelopment coop rationed with RXPE and China Southern Power Grid.In various of the structures of the STATCOM scheme selection, We can see thatSTATCOM structure have been diversificationed. From the beginning of the multiplextechnology to present a chain structure. The topological structures of the STATCOMare also changed constantly with the development of times. As the current mostadvanced topological structure in technology and application, MMC structure andchain structure of STATCOM has its advantages. However, the detailed comparativeanalysis with respect to the relatively few studies at present. This paper is mainlybased on this consideration. For the chain STATCOM and MMC structure in allaspects of performance comparison. Combined with the engineering example analysispart. In the structural form, Make comparison between the basic unit of structure andworking mode. Calculation of the respective device utilization rate, and given acontrast table as description. In connection mode, Draw lessons from the35Kv,±200Mvar chain STATCOM scheme, Analysis of the star and the angle joint in therespective performance parameters. For the MMC structure, its connection modefixed. But this connection mode could effective solved the problem of the move ofzero sequence voltage in star connection structure. The development trend ofSTATCOM equipment is for high voltage and large capacity.So,it will increase thenumber of the device devices. It will Influence the circuit parameters. This paperanalyze the influenction of open loop response time when the circuit parameterschange between this two structures. Analyzing it in the same standard, from this wecan see that the MMC structure have lower influence of circuit parameters.But,because of its fixed connection mode and its special structure, its control strategy havelimitations, its redundancy design complexed. Therefore, there have few projectexample.At the and of this paper,there is a new structure to be Introduced, and makeanalysis ion of it. The appear of this structure Indicate the STATCOM’s futuredevelopment trend—High performance, Stable, Cost-saving and high voltage andlarge capacity.