Industry News

  Effective reduction of comprehensive line losses in power systems relies heavily on two key technological approaches: optimization of power grid planning and optimization of reactive power configuration.

1. Optimization of Power Grid Planning
  Urban power grids can achieve significant line loss reduction through well-designed grid planning. Taking the Shanghai power grid as an example, the system has been developed to meet the N-1 criterion for distribution networks, with some areas even maintaining this standard during maintenance periods. The planning process comprehensively considers multiple factors including short-term and long-term regional load density, energy conservation requirements, loss reduction targets, and power transmission channels from external sources.

  The Shanghai grid has adopted a coordinated development strategy across all voltage levels, establishing high-voltage distribution networks adapted to local conditions. A notable initiative includes vigorous development of 110 kV grid frameworks and implementing direct 110 kV to 10 kV power supply systems. These efforts are directed toward building energy-efficient, low-consumption distribution networks that meet modern requirements.

  The urban development pattern of Shanghai has led to a focus on PVC plastic network development in central urban areas, complemented by compact, miniaturized substations and distribution stations designed to harmonize with the urban environment. To further reduce line losses and improve voltage quality, the Shanghai grid has implemented medium-voltage distribution network extensions into residential areas, effectively reducing the coverage range of low-voltage distribution networks. This approach enables multiple power supply points with shorter supply distances, supplemented by the deployment of low-loss and low-noise equipment.

2. Optimization of Reactive Power Configuration
  Excessive reactive current in power grids leads to increased line losses, reduced transformer utilization efficiency, and customer voltage drops. Reactive power compensation represents one of the most crucial technical measures for reducing line losses, enabling rational distribution of reactive power while maintaining optimal active power allocation.

  The primary objective of reactive power optimization is to minimize active power loss across the network by adjusting reactive power flow distribution while maintaining satisfactory voltage levels. Optimization typically involves three main approaches: reactive load compensation at substations, compensation along distribution lines, and compensation on the low-voltage side of distribution transformers.

  According to power loss formulas, when the active power transmitted through lines or transformers and the voltage remain constant, line loss is inversely proportional to the square of the power factor. Lower power factors necessitate more reactive power from the grid, resulting in higher line losses. Therefore, installing reactive power compensation devices at receiving ends can effectively reduce reactive power loss, improve power factor, and enhance the active power output capacity of electrical equipment.

  With ongoing advancements in power electronics technology, there is growing emphasis on pilot applications of active filtering devices and static synchronous compensators (STATCOM), representing promising developments in reactive power optimization technology.