Protection device - A set of hardware equipment that issues alarm signals or trip commands when power components (such as generators, lines, etc.) in the power system or the power system itself experience faults or events that endanger its safe operation. Devices for protecting power components are called relay protection devices; those for protecting the power system are called safety automatic devices. This regulation collectively refers to protection devices.
1.2 Line Protection - Two sets (or more) of line longitudinal protection (including protection channels), backup distance and zero-sequence protection. For 500kV lines, overvoltage protection and remote tripping devices are also provided.
1.3 Short-circuit Protection - A protection measure for the section of equipment between the outgoing circuit breaker and the two circuit breakers, when a semi-breaker connection method is used and an isolation switch is installed at the line outlet. This protection is activated when the line is de-energized and both circuit breakers are in operation; it is deactivated when the line is in operation or when both circuit breakers are disconnected. (Incorrect statement)
1.4 Circuit Breaker Protection - Circuit Breaker Failure Protection, Circuit Breaker Phase Unbalance Protection.
1.5 Protection Input - 1. Connect the export trip circuit; 2. Connect the start (lockout) reclosing circuit; 3. Connect the start circuit breaker failure circuit; 4. Connect the protection channel transmission-reception circuit or put in use the dedicated transmission-reception device; 5. Connect the start remote trip transmission-reception circuit.
1.6 Exit Protection - 1. Disconnect the export trip circuit; 2. Disconnect the start (lockout) reclosing circuit; 3. Disconnect the start circuit breaker failure circuit; 4. Disconnect the protection channel transmission-reception circuit or deactivate the dedicated transmission-reception device; 5. Disconnect the start remote trip transmission-reception circuit; 6. Disconnect the automatic generator tripping and load shedding circuit.
1.7 Activate Reclosing Function - Connect the reclosing output circuit, and set the reclosing mode to "Single-phase Reclosing".
1.8 Disable Reclosing - Disconnect the reclosing output circuit, and set the reclosing mode to "Reclosing Disabled".
1.9 Inputting circuit breaker protection - Connect the failure protection of the circuit breaker, and the tripping circuits of the three-phase inconsistency protection.
1.10 Exit circuit breaker protection - Disconnect the trip circuits of the circuit breaker failure protection and the three-phase inconsistency protection.
1.11 Put in-service the line protection - Put all the line protection into operation.
1.12 Exit Line Protection - Completely deactivate the line protection.
1.13 Comprehensive Reclosing Mode (1/3P) - For single-phase faults, single-phase tripping triggers single-phase reclosing; for single-phase faults, tripping all three phases does not trigger reclosing. For inter-phase faults, three-phase tripping triggers three-phase reclosing; for permanent inter-phase faults, tripping all three phases does not trigger reclosing.
1.14 Three-phase Reclosing Mode (3P) - For any type of fault, three phases are tripped and then reclosed. For permanent faults, three phases are tripped but not reclosed.
1.15 Single-phase Reclosing Mode (1P) - For single-phase faults, single-phase tripping followed by single-phase reclosing; for phase-to-phase faults, all three phases trip without reclosing.
1.16 Exit Method (OFF or NORECL) - In case of any type of fault, three-phase trip without re-closure.
1.17 Line Protection - A type of protection that causes the switches on both sides or multiple sides (branch lines) to trip simultaneously and rapidly when a fault occurs on the line. It uses a specific relationship between certain quantities on each side of the line as the action criterion. That is, each side will transmit the detection quantity through the channel to the opposite side, and then each side will separately determine whether it is an internal or external fault based on the relationship between the detection quantity of the opposite side and that of its own side.
1.18 Allowable Mode - Utilizes information sent from the opposite side to indicate faults within the specified positive direction range. When the opposite side's information is received and the discrimination element on this side operates, it is determined as an internal fault and a trip command is issued.
1. 19 Locking Type - Utilizes the received signal as the locking protection. When the signal is received, it is determined as no fault or an external fault, and the export trip circuit of this side's protection is disconnected. When no information is received from the opposite side and the discrimination element on this side operates, it is determined as an internal fault, and a trip command is issued.
1. 20 Over-range Permitting Type - The signal is initiated by the first section of the component whose forward protection range is less than the total length of the line. The action criterion is based on the operation of the local fault discrimination component and the receipt of information from the opposite side.
1.21 Over-range Permitting Mode - The signal is initiated by an element whose forward protection range is greater than the total length of the line. The action criterion is based on the operation of the same element on this side and the receipt of information from the opposite side.
1.22 Differential Protection - The protection operates based on the vector (phase and amplitude) relationship of the currents on both sides of the line.