Smart Distribution Network Fault Self-healing Control Technology

The purpose of building a smart distribution network is to realize the needs of safe and stable power system operation, high quality and reliability, and economic and environmental protection. In-depth development of intelligent distribution network with functions such as optimized structure, fusion of differences, coordinated early warning, distributed power supply, fault self-healing, interactive communication, etc. is of great significance to the implementation of sustainable power supply strategy. Today we will take a detailed look at the fault self-healing control technology of smart distribution network.

The "self-healing" ability of the smart distribution network means that the smart distribution network can accurately predict the defect state and timely alarm the fault state that has occurred, and implement corresponding reliable measures so that the distribution network will not stop normal power supply on a large scale or will Its blackout range is minimized. Self-healing control technology mainly solves a problem, that is, "uninterruptible power supply", monitors the operation status of the power grid in real time through information systems and auxiliary equipment, predicts equipment defects in a timely manner, quickly eliminates potential safety hazards and independently eliminates power grid faults.

Types of smart distribution network self-healing control technology Distribution network self-healing control technology is based on the premise of state detection, automatically diagnoses the current operating status of the power grid, uses intelligent control strategies for decision-making and diagnosis, and realizes relay protection devices, intelligent The automatic and orderly control of switches, safety automatic devices and automatic adjustment devices can promote the power grid to turn to a better operating state within a preset time, so that the distribution network has self-healing ability.

1. According to the health of the smart distribution network, the self-healing control of the distribution network can be divided into 7 types, as follows:

1. 1 Emergency control: When an emergency fault occurs in the distribution network, in order to maintain safe and stable operation and continuous power supply, the system must take decisive control measures in time to remove the faulty equipment, cut off the power supply, cut off the load, and actively unload, so that the system turns to recovery state, abnormal operating state, or normal operating state.

1.2 Restoration control: After the distribution network accurately isolates the fault, the power grid system immediately enters the recovery state, independently selects a reasonable power supply path, quickly restores the load power supply in the power outage area, merges the isolated island operation area into the network, and restores to the abnormal operation state. even normal operation.

1.3 Island control: In the case that the distribution network cannot be restored to normal operation immediately, the distribution network is separated from the system into one or more isolated islands for independent operation, and effective control is implemented to keep its active frequency and voltage within a stable range, so that The island can supply power normally until the island is connected to the grid again.

1.4 Correction control: When the distribution network is in an abnormal operation state, according to the abnormal signal detected, it is controlled by the adjustment mechanism to eliminate overload, voltage fluctuation, frequency jump, etc., so that the power grid can return to the normal operation state as soon as possible.

1.5 Prevention and control: When there are hidden safety hazards in the distribution network, the system will eliminate the safety hazards of the distribution network by checking and repairing the secondary system, adjusting the setting value of the protection device, adjusting the reactive power compensation equipment, and withdrawing the aging equipment. Maintaining an explicit and safe operating state can effectively eliminate hidden dangers in the bud.

1.6 Optimal control: In order to further improve the stability of the system when the distribution network is in dominant safe operation, by adjusting the power supply path, sharing the load pressure of the heavy load line, optimizing the operation mode of the power consumption terminal, and adjusting the reactive power compensation equipment, etc., It can reduce the loss of the power grid, reduce the operating cost, and better improve the operating efficiency of the enterprise.

1.7 Robust control: When the distribution network is operating in explicit security, in order to make the system in the most robust state, the occurrence of faults is minimized by strengthening the construction of the grid structure, reducing the load rate of equipment, and increasing the reserve margin.

The characteristics of self-healing control technology of smart distribution network The revolution of information technology and the application of new power distribution technology have promoted the process of intelligent distribution network. Smart distribution network is the organic integration and integration of various new power distribution technologies. Revolutionize system performance.

2. "Active" self-healing technology is a prominent feature of smart distribution network self-healing, and its characteristics are as follows:

2.1 Higher degree of automation The active self-healing technology not only realizes the online monitoring of system operation status, but also conducts online accurate assessment and rapid diagnosis of the distribution network status, and actively eliminates hidden faults, realizes self-healing of the power grid, and restores normal operation. The whole process is automatically controlled by the system, requiring little or no manual intervention.

2.2 The degree of informatization is stronger. Active self-healing can report the real-time operating status of the power grid system synchronously, which helps the control center to understand the operating status of the distribution network in real time and perform dispatch control in real time.

2.3 Higher security The active self-healing technology can automatically eliminate potential safety hazards of the system and automatically isolate faults to ensure effective control of the expansion of potential safety hazards and minimize the occurrence of faults.

2.4 Better power supply quality Active self-healing technology can quickly locate faults, isolate faulty areas, and restore power supply, minimizing the impact on users, which is of great significance to improving power supply quality.

2.5 Stronger initiative The active self-healing system monitors the operating status of distribution network equipment in real time, integrates the obtained data for scientific diagnosis, and proactively predicts hidden dangers in advance, which helps the system to troubleshoot immediately.

2.6 Better interaction The active self-healing system can perform man-machine interactive operation. The system can provide various solutions according to the detection status, and deal with the corresponding situation according to the optimal solution. Authorized operators can actively intervene in the operation of the system state.