跨区域互联电网的可用输电能力计算方法

为确保电网安全,保证跨区域电力交易的正常进行,提出了计算跨区域互联电网可用输电能力的方法。相比于其他方法,该方法仅需交换边界节点电压和购电用户有功负荷增长量即可准确地计算出跨区域互联电网的可用输电能力。首先,建立了适用于可用输电能力计算的外网等值模型,使各个区域从互联电网中解耦。同时,建立了虚拟的平衡节点和自动调节的边界注入功率,使各个区域可以进行独立的潮流计算。然后,采用分布式潮流计算对区域电网的潮流进行校正,旨在减小各个区域电网潮流计算的偏差。最后,根据定义计算出了跨区域互联电网的可用输电能力。通过IEEE 118节点系统的仿真计算,证明了该方法的有效性和准确性。

Calculation Method of Available Transfer Capability for Cross-regional Interconnected Power Grid

For keeping power systems safety and ensuring the cross-regional electricity trading, a calculation method of available transfer capability(ATC)for cross-regional interconnected power grid is proposed. Compared with other methods, only boundary bus voltages and increment loads at buyer bus are sent to/received from other areas. Firstly, an external network equivalent, which is suitable for ATC computation, is built to decompose the inter-connected power grid. Secondly, fictitious slack buses and auto-adaptive power injections are set that each area can run its own repeated power flow. Thirdly, distributed power flow calculation is used to correct power flow in every area, which prevents a larger mismatch happening in areas'' power flow calculations. Finally, the ATC for the cross-regional interconnected power grid is computed based on ATC definition. According to simulations on IEEE 118-bus test system, the method is proved to be effective and accurate.