The standby power automatic input device refers to the automatic and accurate putting of the standby power into the electrical equipment or switching the equipment to the standby power supply when the line or electrical equipment fails, so as to ensure uninterrupted power.
The main criterion for the automatic feed-in device for standby power is the position of the two bus voltages and the three switches. In the case that the bus is pressurized and the real circuit breaker can be operated, we can drive the standby self-throw by "pulling the switch". The bus voltage is normally input to the standby self-throwing device, DL131, DL231 are combined, and DL100 points (red represents merging, green represents disconnection), as shown in the following figure:
Pull the air switch of the II female voltage input, and the standby self-throwing device senses the II female voltage loss, and will jump out of the incoming line 2 circuit breaker DL231 and the bridge (segment) circuit breaker DL100, as shown in the following figure:
If there is no bus voltage, the test needs to use the relay to add two sets of voltages to the self-throwing device.
Wuhan Halma Power Relay Protection Star-1600 relay protection test system has 6-phase voltage and has a special standby self-throwing experimental module, which is convenient for standby self-throwing device test. Next, let's take a look at how to use only 4 phase voltage and 4 channels to openRelay Star-S series handheld relay protection test systemConduct a standby self-delivery test.
If three real circuit breakers can be operated, only two sets of voltages need to be provided by the handheld relay instrument, and the wiring method is as follows:
Connect UA, UB and UC to the I bus voltage input terminal, connect a set of voltage lines in parallel at the voltage output terminal of the handheld relay instrument, connect them to the opening contact of the relay protection instrument, and then connect the II bus voltage from the other end of the relay protection instrument opening contact. At this time, the opening contact of the relay Baoyi acts as a three-phase air opening, which can be controlled by the software to open and close to simulate the pressure and loss of pressure of the II mother. When it is necessary to simulate the voltage and loss of voltage in the I female, the two sets of voltage lines connected to the terminal row of the standby self-throwing device can be exchanged.
This test is usually performed using a "state sequence".
The first state is set to the pre-fault state: set the voltage to 57735V, the output 1 4 state is all set to close. I and II voltage input backup self-throwing device, and then manually put the circuit breaker in the appropriate position for self-throwing charging.
The second state is all points, and the opening contact of the relay is in the disconnected state, which can simulate the loss of voltage of the II mother.
The above wiring method occupies all the outlets. If we can't operate the real circuit breaker and need to use the opening node to simulate the position of the circuit breaker, we can use the following wiring method to simulate 2 sets of voltages with 4 voltages.
As shown in the figure above: the UA of the relay instrument is connected to the UA of the self-throwing i mother; UB is connected to the UC of the self-invested I female; UC is equipped with the UA of the self-pitched II female; UX is connected to the UC of the self-throwing II female; The UB of the self-throwing I and II females is shorted and then connected to the UN of the successor to the Baoyi. The state sequence should set four states:
1) Before failure. UA and UB will simulate the I bus voltage, the amplitude is set to 100V, and the phase difference is 60°; Both UC and UX will simulate the II parent voltage, with amplitude set to 100V and phase difference of 60°. Because the opening of the relay is connected to the closing signal (HWJ) of DL131 and DL231 respectively, the opening state is set to be closed, which means that the incoming DL131 and DL231 circuit breakers are in close position.
2) Fault states. If the UC and UX voltage are set to 0, it means that the II female voltage is lost, and the trip delay of the fake device self-throwing device is 1s, then the output time of state 2 is 0 times greater than the fixed value1s。When entering this state, the standby self-throwing device has not yet sent a trip command to the DL231 circuit breaker, so DL131 and DL231 are still in close position, and the open state is still closed.
3) After tripping. After the II female loses voltage, the standby self-throw detects that the DL231 is disconnected and will give the DL100 a closing command. Therefore, the opening volume 1 state is set to closed, which means that DL131 is closed, and the opening volume 2 state is set to open, indicating that DL231 has jumped away. The output time of this state should be greater than the closing time of the standby self-throwing device, assuming that the closing time is 15s, then set 16s is more suitable.
4) Coincident. In a traditional substation, after the tester simulates the first three states in turn, the standby self-throwing device will issue a command to close the DL100 outward, and the standby self-throwing test is over. If the coincident state is not set, the standby self-throwing device may report the self-throwing failure because it does not receive the closing position of the DL100. When the fourth state is set, the I female and II female are under pressure, and the DL131 and DL100 are in place, and the output time is arbitrary.