Energy storage high voltage direct hanging

What is high voltage cascaded energy storage power conversion system?

High voltage cascaded energy storage power conversion system, as the fusion of the traditional cascade converter topology and the energy storage application, is an excellent technical route for large capacity high voltage energy storage system, but it also faces many new problems.

Is large-scale energy storage a good idea?

Large-scale energy storage is favorable currently. The capacity expansion needs to be realized by the parallel connection of multiple low-voltage small-capacity PCSs and connected to a medium- or high-voltage power grid through the transformer. The connection would lead to the problems of low efficiency, high cost and unnecessary land occupation.

Can a high-frequency transformer isolate energy storage battery?

Compared with the conventional topology [ 22, 23 ], the energy-storage PCS proposed in this paper is isolated by a high-frequency transformer, which can cancel the power frequency transformer, reduce the volume of passive components, improve the power density of equipment, and reduce the insulation costs of energy storage battery.

Why is energy storage important?

Energy storage can solve the power grid’s requirements of transient stability and short-term power balance and can be used for long-term power regulation. It can effectively deal with the systemic peak valley regulation and blocking of transmission and distribution lines [ 1, 2 ].

Can a transformer-less high-voltage PCs be used in China?

In China, Shanghai Jiaotong University and China Southern Power Grid proposed a transformer-less high-voltage PCS in 2014. A set of 10 kV/2 MW/2 MWh device prototypes has been developed and applied in Baoqing energy storage power station of the China Southern Power Grid [ 22 ].

What is the peak value of transient overvoltage at LVDC?

The peak value of transient overvoltage at the LVDC side is about 720 V and overshoot is about 0.02%, and the peak value of transient overcurrent at the LVDC side is about 480 A and overshoot is about 68.4%, which is within the allowable range. Under the condition of 20% rated power, the output current THDi is 3.31%, as shown in Figure 8. Figure 7.