The objective of this experiment is to study the steady-state operation of the BESS.
Real-time simulation results are shown in the “Main Interface” and “Help Contents” tabs of the laboratory panel.

Grid Connected Mode

• Start with the PQ operation mode, which enables the control of active power P and reactive power Q.
  Set the reference value P_ref to 1 p.u.
  Is the measured value for P equal to the desired value?
• Set P_ref to 0.8 p.u. and Q_ref to 0.5 p.u.
  Do P and Q follow the given reference values?
  Increase Q_ref and determine the maximum value for that P and Q can follow their reference values P_ref and Q_ref.
• With P_ref = 0.5 p.u. and Q_ref = 0.5 p.u., change to the PV operation mode that enables the control of the active power P and the voltage V.
  What are the differences to PQ Mode?

Islanded Operation Mode

• Change to PQ operation mode with P_ref = 0.8 p.u. and Q_ref = 0.5 p.u.
  Then change to the islanded (grid forming) operation mode.
  The BESS is now disconnected from the grid at switch B3 (see figure 2).
  Notice that once in grid forming mode, the P and Q references are no longer followed while the voltage magnitude at the PCC is now 1 p.u.
  and the frequency is at 1 p.u. (50 Hz) as the BESS regulates both parameters to their rated values.
  How does the islanded mode impact the power flow?
  How does the BESS impact the grid in islanded operation mode?
• Explain why it is not reasonable to set P_ref  to a negative value in the given islanded operation mode.