Switch control energy storage circuit

How is DC-bus voltage controlled by a normal switch strategy?

The DC-bus voltage controlled by the normal switch strategy using the dual-loop PI method is plotted by the red line, and that controlled by the proposed switch strategy using the angle compensation is shown by the green line.

What is a normal switch strategy?

For the normal switch strategy, the oscillation value of the DC-bus voltage reaches 136 V from the holding stage to the discharging stage. For the proposed switch strategy using the compensation model, the variation of the DC-bus voltage is reduced to 102 V during the switching process.

Does a state switch affect the power converter?

Finally, the simulations and experiments are performed to validate the performances of the switch strategy used in the FESS-UPS system, and the results prove that the current/voltage peaks during the switching process are effectively mitigated, so the impact on the power converter caused by the state switch is suppressed.

What is a fess-ups switch strategy?

Then, the switch strategy using the angle compensation of the flux linkage is designed to control the FESS-UPS system among different working states, and the peak values of current and voltage at the switch moment are suppressed.

How does the extended state observer improve the charging efficiency?

In reference 24, for the FESS-UPS system, the designed extended state observer improved the charging efficiency and the proposed sliding mode control method reduced the oscillation of the outputted DC-bus voltage, and the oscillation at the switch state from the charging to the discharging was not suppressed.

What is a magnetically suspended flywheel energy storage system (MS-fess)?

The magnetically suspended flywheel energy storage system (MS-FESS) is an energy storage equipment that accomplishes the bidirectional transfer between electric energy and kinetic energy, and it is widely used as the power conversion unit in the uninterrupted power supply (UPS) system.