• Power level: The power level of large-capacity PCS is usually high, reaching the MW level, and can even exceed 100MW. This type of PCS is suitable for large-scale energy storage power stations and can handle large-scale energy conversion demands.  
• Conversion efficiency: The requirement is extremely high. Generally, the conversion efficiency needs to be maintained above 95% to reduce energy loss and improve the economic efficiency of the energy storage system.  
• Response speed: It has a rapid response capability and can adjust the charging and discharging power within milliseconds to ensure the stability of the power grid.  
• System compatibility: It is well compatible with large-scale energy storage battery systems and complex power grids, and can adapt to various battery characteristics and grid access requirements.  

Example:    

        Power range: 10MW - 100MW            

        Efficiency: ≥95%

        Response time: 10ms 

        Input voltage range: 700VDC - 1500VDC

        Output voltage level: 35kV or higher

        Mean Time Between Failures (MTBF) : 100,000 hours

Overcharge protection

        Big Storage:

        Since large-scale energy storage power stations usually adopt energy-type batteries and need to provide power auxiliary services, the requirements for the battery management system (BMS) are very high. The BMS will continuously monitor the status information of each battery cell. Once it detects that a certain battery cell is approaching full charge or the voltage exceeds the set threshold, it will immediately stop charging the battery cell through the PCS and issue an alarm to notify the operator to check the problem. In addition, some advanced PCS also support SOC equalization control function, which to a certain extent avoids the occurrence of overcharging caused by uneven charging of individual battery cells.  

2. Over-discharge protection    

        Big Storage:    

        To ensure that energy storage power stations can stably output electrical energy over a long period of time, it is necessary to strictly control the minimum allowable depth of discharge of batteries. The BMS will monitor the overall State of Charge (SOC) of the battery pack in real time according to the preset parameters, and trigger the PCS to perform corresponding protective actions before the SOC drops to the critical value, such as limiting the discharge power or even suspending the discharge operation, until the SOC rebounds to the safe range.