Method and apparatus for determining phase locking of critical arc light

An apparatus for determining phase locking of critical arc light, wherein

• the apparatus comprises a collection module, a first comparison module, a second comparison module, and a control module, wherein
• the collection module is configured to monitor and collect light radiation intensity of an arc inside a switch cabinet in real time, and convert the collected light radiation intensity into an electrical signal;
• the first comparison module is configured to extract a power-frequency fundamental wave of the electrical signal, compare an amplitude of the power-frequency fundamental wave of the electrical signal with a first threshold, and generate a pre-warning signal based on a comparison result of the first threshold;
• the second comparison module is configured to compare an amplitude of the power-frequency fundamental wave of the electrical signal with a second threshold voltage, and generate a control signal based on a comparison result of the second threshold voltage and a protection time threshold;
• and
• the control module is configured to protect the switch cabinet under the critical arc light environment based on the pre-warning signal and the control signal.