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As a typical continuous manufacturing enterprise, power plants represent a specialized industry with a high level of automation. The automated production equipment relies on the safe, stable, and continuous operation of the power supply system. The DCS control system for large-capacity unit generators, which includes various thermal automation devices such as instruments for automatic regulation, electro-hydraulic digital control devices for steam turbines, the boiler interlock and safety supervision system FSSS, turbine monitoring instruments (TSI), and the coordinated control system (CCS), all require a reliable and continuous power supply. This power supply must not be interrupted, even in the event of a failure in the plant’s own electrical supply or in the grid. Therefore, dual-power redundancy is provided for important control systems and process equipment; by using GSS static transfer switches, rapid and safe switching between the two power sources can be achieved. In the event of an issue with one power source, it is possible to switch to the other safe power source within 5 milliseconds, ensuring that critical and sensitive load devices can continue to operate reliably and thus maintaining the safety and stability of production. Several factors need to be considered before implementing this solution: 1) First, select static switches with an appropriate rated current based on the capacity of the loads. The GSS series of static switches already features a 1.6-fold capacity redundancy built into their design, so this aspect should be taken into account when making selections. 2) If the 0.4 kV distribution room is considered as a distribution system, the flicker phenomenon may originate from higher-level systems outside the area or from within the area itself. If it comes from higher-level systems outside, it can be resolved through rapid switching; whereas if it is caused by a short circuit in one of the outgoing circuits within the area, the switching equipment must have the capability to make accurate judgments and implement safety interlocks to prevent the fault from spreading when it has not yet been isolated. 3) By following a sequence of first separating and then closing, when a closing command is issued, the controller in the switching device must conduct an accurate analysis of the power supply voltage disturbance model, to ensure precise prediction of the amplitude, phase, and frequency of the voltages on both sides during closing, thereby eliminating the risk of shocks. 4) When flickering occurs, it is common for there to be multiple instances of flickering in a short period of time. After the GSS static transfer switch completes one switching operation, the system gets locked, and manual reset is required. Once the main power supply returns to normal, the system can be restored to the operating mode powered by the main power supply, either manually or automatically. 5) Based on the on-site conditions, a bypass isolation transformer is selected to achieve complete isolation between the input and output.