适应于新能源接入的新型备自投方案

New Busbar Automatics Transfer Switch Scheme for New Energy Access

备自投(busbar automatic transfer switch,BATS)是保证电力系统供电可靠性的重要措施之一,然而在“双高”系统下,新能源的“低穿”特征导致母线存在残压,传统备自投难以满足母线无压动作条件。因此,现有方案通常采取先切除新能源电源,再启动备自投方式。为实现不切除新能源进行备自投,以进线备自投为例,在主供线路断路器分闸后,详细分析了新能源并网点电压及频率变化规律及其影响因素,在此基础上,针对“源大于荷”场景,提出了基于耗能电阻的新型备自投方案。通过在并网点根据功率不平衡度投入耗能电阻,实现了在不切除新能源的情况下的备自投。最后通过大量算例仿真验证了新型备自投方案的有效性和可行性。

Busbar automatic transfer switch(BATS) is one of the important measures to ensure the reliability of power supply in the power system. However, under a "dual-high" system, the "low-pass" feature of new energy causes bus residual voltages, making the traditional busbar automatic transfer switch unable to meet the conditions of bus voltage-free operation. Therefore, in the existing schemes,usually the new energy sources are first disconnected and then the busbar automatic transfer switch is started. In order to realize the busbar automatic transfer switch without cutting off the new energy, in this paper, the regularity of voltage and frequency changes at the point of common coupling of new energy and its influencing factors are analyzed in detail under the scene when the main supply line breaker is switched off. On this basis, a new busbar automatic transfer switch scheme based on energy-consuming resistance is proposed for the scenario of "source is larger than load". By putting in the AC chopper according to the power unbalance at the point of common coupling, the busbar automatic transfer switch without cutting off the new energy is achieved. Finally, the validity and feasibility of the new busbar automatic transfer switch scheme are verified by a large number of numerical examples.