Generator dual power switching logic

Let’s talk about the switching problem of security power supply, we have three assumptions initial conditions, as shown in the figure (see Figure 1 for details). Initial conditions 1-3, condition 1 is the feeder switch 08, 09, 12, and 13 are in the closed position, initial condition 2 is the feeder switch 01, 02, and 03 are in the closed position, initial condition 3 is the feeder switch 07, and 10 are in the closed position. Through the above initial conditions, we know that when the initial normal operation is initially normal, the working PC1 section is running with security MCC1 section, and the working PC2 section is running with security MCC2 section.

The generator dual power switching logic

switch logic 1: jump to switch 09, security MCC1 section loses power, switching logic will instantly jump to switch 07, delay 11 switch. In this way, the security MCC1 section is powered by the working PC2 section, and a switching is completed. The switching between the two sections is generally completed within 1-2 seconds, or less.

Switching logic 2: When the power supply of the switching logic is completed, switch 13 will be switched off, and the security MCC1 section will lose power again. The switching logic will instantly jump on switch 11, and at the same time send a start command to the diesel generator, and the concurrent command will be combined with the 05 switch. When the diesel generator reaches the rated voltage, it will automatically close the diesel generator outlet switch. This completes the second switching, and the diesel generator will supply power to the security MCC1 section instead of the working PC2 section. Due to different characteristics of diesel generators, this switch usually takes more than ten seconds. Generally, it is long enough to consider more than ten seconds from a safety perspective. Some power plants may switch between twenty or thirty seconds, so it is estimated that the important equipment below will jump into one.

Turn back logic 1: Turn 13 switch, switch 05 will jump instantly, and switch 11 will be delayed. The security guard MCC1 section completes the conversion from the power supply of the diesel generator to the power supply of the working PC2 section. In the switching logic, the diesel generator often has no stop logic, so we can just stop it manually.

Turn back logic 2: Turn 09 switch, switch 11 will jump instantly, and delay switch 07 will be closed. The security guard MCC1 section has completed the conversion from power supply to power supply from working PC2 section to working PC1 section.

It is worth noting that during the switching process, the switching logic is to judge the voltage of each segment. When the corresponding switch jumps or closes, the switching logic will first determine whether the voltage condition of the segment to be switched is satisfied. Only when it is satisfied will the switching program I mentioned later will be executed.

Here we only talk about the switching logic of the security MCC1 paragraph. The security MCC2 paragraph and the security MCC1 paragraph are similar, so I won’t talk about it anymore. You can also refer to the switching logic of the self-projection device.