Condition descriptions: Due to the dramatic increase in the amount of electricity usage, the traditional power system operating modes such as centralized power generation, long-distance transmission, and large grid interconnection is unable to meet the requirements any longer. Moreover, with the increasing depletion of the resources and people’s increasing awareness of environmental protection, the full use of primary energy and renewable energy attracts much attention of all countries in the world. A new generation technology - the distributed generation that is highly efficient and environmentally friendly has been born as times require. The distributed power supply is usually directly connected to the distribution system (0.4kV or 10kV distribution system) for grid-connected operation. Because of this access, the distribution network becomes a multisource network from the traditional single-supply radiation network. The distribution of power flows during normal operation changes accordingly. Meanwhile, in case of failures, the size, direction and distribution of the short-circuit current also change, which prove that the access of distributed power supply causes many impacts on the distribution network. Banner Electric, in virtue of many years of experience in the research, development and promotion of automation, information, and interactive products in the field of smart grid power distribution, proposes a distribution network distributed energy management and control system to solve this problem. Solutions: Banner Electric puts forward a distribution network distributed energy management and control system based on the idea of local networking, regulations and absorption, which ensures enough quantity of distributed energy generated while the impact on the distribution network is minimized. The system has two regulation levels of regulation, first, to install a smart transformer area comprehensive control device on the low voltage side of the 10kV/0.4kV transformers to balance the power generation and power consumption in the transformer area and avoid the back-fed system power; second, to detect the real-time current,
direction and four quadrant active and reactive power at the 10kV branch line entrance, and conduct real-time adjustment of 10kV static var generator, operating parameters of 10kV grid-connected distributed power station in order to achieve balance of power generation and consumption of 10kV singlebranch buses. Under the management and control of this system, the power generated by the distributed power generation is effectively controlled at the local area, which will not cause any impact on the power transmission network. Through the local grid connection and consumption, the operating pressure of the power transmission network can be greatly reduced, and the transmission loss can be minimized.
Available equipment and system: Intelligent transformer area integrated management device; 10kV static var generator (SVG); Grid-connected inverter; Distributed energy access control software;
