青南新能源集中送出地区动态无功补偿方案对比研究

Comparative Study on Dynamic Reactive Power Compensation Scheme in the Concentrated Delivery Area of New Energy in Southern Qinghai

为解决青南高比例新能源集中送出面临的暂态过电压等问题,提出了新型分布式调相机动态无功补偿方案。通过对比分析直流典型故障期间不同动态无功补偿设备及接入方式对新能源场站母线过电压抑制能力和低电压支撑能力,筛选出最好的动态无功补偿方案。研究表明,在新能源场站35 kV母线或110 kV汇集站通过三绕组变压器接入分布式调相机的方案具有更好的无功补偿效果,综合考虑升压变成本和调相机单位容量造价,后者更具经济优势。

To solve the problem of transient overvoltage occurred in the centralized delivery of high proportion new energy in southern Qinghai,a new dynamic reactive power compensation scheme based on distributed synchronous condensers was proposed.By means of contrastive analysis on different dynamic reactive power compensation devices and connecting modes during typical DC faults,an optimal dynamic reactive power compensation scheme was filtrated for the over-voltage suppression and low-voltage support capability of buses in new energy station.Results of the research show that the scheme,in which the 35kV bus bar or the 110kV gathering station in new energy station are connected with distributed synchronous condenser via three-winding transformer,possesses a better effect of reactive power compensation.Overally considering the cost of the step-up transformer and that of unit capacity of the synchronous condenser,the proposed scheme is of economic advantages.