Data acquisition and processing units are usually based in the currently used high-voltage circuit breaker protection control system.AC input signal above 1 week / 20ms (20ms), calculates the various electrical feature amounts required to extract the desired electrical feature by FFT transform (or DFT transformation, root calculation, etc.), and then according to the protected retreatment, the setting of the action, etc. Determine whether to send the protection action outlet signal; the switch output circuit usually uses an output relay, the intermediate relay realizes the separating brake drive, due to the output relay, the mechanical contact of the intermediate relay has a certain response time, the delay time of the general output relay is 5ms The above, the delay time of the intermediate relay is more than 8 ms, that is, the protection control system has a fault current from analog input circuit to give a divided clock drive signal, and at least 30.5 ms or more delay (ignore software calculation time) . The response time increases the impact time of the fault current to the grid, reducing the actual operating life of the grid, and is not conducive to fast fault isolation.
Our company has developed a high-voltage circuit breaker rapid protection control system with independent intellectual property, which makes the protection control system from analog input circuit from analog input circuit from an analog input circuit to a fracture drive from an analog input circuit by shortening the measurement and protection operation. The delay time of the signal is reduced, thereby shortening the impact time of the fault current to the grid to achieve rapid protection.
The separation brake circuit in the switch output circuit of the rapid protection control system uses an electronic divider brake circuit instead of conventional mechanical contact relays and constitutes a fast output circuit of the switch. At the same time, the half-wave symmetry is used and the recursive operation, and the first half of the waves are calculated in each sampling point.10ms) The various electrical features required for time, thereby shortening the time of fault current measurement and issuing protection control signals. When the fault current is greater than the current value, the delay time of its protective action signal will be less than 10 ms + 20ms / per week wave sample point, and the electronic separator brake circuit is used instead of the conventional mechanical contact relay constitutes a quick output circuit, The delay time is less than 0.1 ms, thereby shortening the protection control delay time. The circuit breaker rapid protection control system has a fault current from an analog input circuit to give a split drive signal, and only 10.4 ms of delays in the slowest (when the sample point is 64 points). Therefore, the fault line can be quickly isolated, and the holding time of the power grid fault current is reduced, thereby achieving rapid protection control.