Energy storage millisecond emergency control

What is the energy recovery control strategy of ESS?

In this section, an energy recovery control strategy of ESS is proposed, which aims to quickly recovery energy of ESS to initial value and guarantee the frequency of the disturbed system within stability range. Similar to Section 3.1, the MASF model is used to analyze the dynamic behaviour of the system frequency.

Does energy recovery control prevent system frequency dropping below stability threshold?

It is shown that when the energy recovery control ends at about 9 s, the energy of ESS also recovers to the initial value. In summary, the proposed control scheme successfully prevents system frequency dropping below the stability threshold and completely recovers energy in the ESS.

What is the optimal power support trajectory for VSC-HVDC and ESS system level?

For HVDC and ESS system level, based on Pontryagin minimum principle, the total optimal power support trajectory of VSC-HVDC and ESS is determined aiming at minimizing total control energy, which guarantees system frequency above the stability threshold value.

Can emergence control improve post-contingency system security?

Combined with the uncertainties it introduced, the risk of a system being transient instable is significantly alleviated. This paper proposes a multi-objective coordinated post-contingency control method. It aims to increase post-contingency system security with emergence control (EC) while minimizing the total control cost.