巴西美丽山特高压双回直流工程协调策略设计

Coordination Strategy Design for Belo Monte Double-circuit UHVDC Project

巴西美丽山特高压直流工程为双回直流送出工程,两回直流工程隶属于不同的项目公司,没有统一设计,且分期建设、各自管理,不同的设备供货商在设计理念上存在差异。针对以上问题,开展了主控系统设计,提出两回直流工程有功控制协调策略,可实现两回直流功率相互支援,有利于电网稳定运行。针对两回直流工程无功控制都采用定交流电压控制,提出两回交流滤波器的协调控制策略,在两回交流滤波器各自独立控制的情况下,可实现有序投退。针对两回直流工程在欣古换流站共用接地极的运行方式,提出了相应的控制保护策略,满足两回直流工程共用接地极运行的需要。通过联调试验和现场运行,验证了所述设计方案的有效性。

Belo Monte ultra high-voltage direct current(UHVDC)projects in Brazil are double-circuit DC transmission projects.The double-circuit DC projects belong to different project companies with no unified design,phased construction and separate management.Different equipment suppliers have different design concepts.To solve the above problems,the main control system is designed,and an active power control coordination strategy for double-circuit DC projects is proposed,which could achieve mutual support for the double-circuit DC power and facilitate stable operation of the power grid.Considering the reactive power control of double-circuit DC projects both use the constant AC voltage control strategy,a coordinated control strategy for doublecircuit AC filters is proposed.In the case where the double-circuit AC filters are controlled independently,orderly switching can be achieved.Aiming at the operation mode of the double-circuit DC projects sharing ground electrodes in Xingu converter station,the corresponding control and protection strategies are proposed to meet the needs of the double-circuit DC projects sharing the common ground electrodes.Through the joint test and on-site operation,the effectiveness of the design scheme is verified.