Application of dc bus in solar container power station

Can a PV/BES grid-connected system eliminate the DC-bus trade-off?

One of the main challenges in single-phase PV/BES grid-connected systems is the trade-off between DC-Bus voltage variations, total harmonic distortion (THD) of the output current, and the size of the DC-Bus capacitor. The work presented here investigates this problem and proposes a PV/BES grid-connected system that eliminates this trade-off.

Why is DC-BUS capacitor important in PV inverters?

In standalone and grid-connected PV structures, DC-Bus capacitor is the extremely important passive component. Harmonics and power factor reduction occur in single-phase PV inverters because the DC bus voltage exhibits a double frequency ripple.

How to stabilize DC-bus voltage?

In 17, 18, the fluctuating DC-Bus voltage was actively stabilized by modifying the DC-Bus dynamic impedance to be positive. Since the output power is related to the output current, modifying the current command in 19 may be used to change impedance.

What causes a DC bus to overvoltage or undervoltage 20?

Speedy load changes can potentially cause the DC-Bus to overvoltage or undervoltage 20. The DC-Bus voltage will reduce the substantially if the output power is raised in steps, for example, since the energy stored in the capacitor is inadequate to maintain the DC-Bus voltage.

How is DC-bus voltage error handled?

The DC-Bus voltage error was handled by PI gains, Kp and Ki, during disturbances at the DC-Bus such that the DC-Bus voltage followed the voltage set point (Vdc-ref = 400 V), as seen in the Fig. 11. The PWM generation circuit receives the output signal from the PI controller, which is then utilized to decide between buck and boost mode of operation.

How to engross power from DC-BUS?

To engross power from the DC-Bus, switch S 1 is activated and S 2 is deactivated during step-up discharge mode, whereas S 2 is triggered and S1 is deactivated during step-down charge mode. Figure 11.