System overview
■ scheme purpose: realize automatic fault isolation and automatic power transfer;
■ scheme composition: electric switch + integrated intelligent terminal of protection, measurement and control + monitoring system of backup master station; (flexible communication mode: supported by optical fiber / carrier / wireless)
■ technical index: complete fault isolation and power transfer within 10s (depending on the switch level);
■ features of the scheme: low investment, quick effect, high reliability, fault handling independent of communication;
■ realization mode: the intelligent terminal adopts voltage time type, current time type, voltage current time type (u-i-t), user intelligent demarcation type and other fault handling modes, comprehensively utilizes the advantages of voltage sectionalizer, current sectionalizer and recloser, detects the line voltage and current status, uses the terminal's own logic judgment function to realize fault isolation and automatic transfer supply Electricity.
System characteristics
■ in case of line failure, the outlet switch of the substation can realize rapid protection action without disturbance, cut off the fault and complete automatic load transfer;
■ the fault handling process does not rely on the communication channel, the equipment is flexible, the master station does not participate in the action process, monitors the load rate after load transfer, and gives the optimization decision, the system is stable and advanced;
■ adopt the function of "residual voltage detection" to make the switch on the load side of the fault point open and lock in advance, so as to avoid the short-circuit impact and unnecessary power cut when the power supply on the other side turns to the fault line;
■ the half wave current source technology is adopted to realize the network positioning scheme for the line grounding fault, which has high cost performance and accurate positioning.
system function
■ fault handling: through mutual cooperation between intelligent switch controllers, fast fault removal and automatic power transfer can be realized;
■ distribution network management: realize the "four remote" control of distribution network operation.
■ in case of line failure, the outlet switch of the substation can realize rapid protection action without disturbance, cut off the fault and complete automatic load transfer;
■ the process of fault handling adopts the communication mode of pair equation or master-slave mode, so the fault handling is fast and accurate. The master station does not participate in the operation process, monitors the load rate after load transfer, and gives the optimization decision. The system is stable and advanced;
■ after the system communication channel fails, the intelligent terminal has the fault-tolerant function. For the master-slave communication mode, it can automatically switch to the successful recloser mode, and continue to play the automatic fault processing function. For the peer-to-peer communication mode, the intelligent terminal can automatically determine the fault range without affecting the system operation effect.
system function
■ fault handling: the intelligent terminal determines the operation of terminal equipment on the same fibre channel through high-speed fibre channel information sharing, so as to realize fast fault removal and automatic power transfer;
■ distribution network management: realize the "four remote" management and control of distribution network operation, and optimize the power supply mode.