Causes of battery interference in energy storage inverters

How do inverter designs affect battery storage systems?

The design of battery storage systems includes technology choices for the batteries and for the inverter. The impact of the inverter design on the optimal design and operation of the storage system has not been analysed before. Therefore four inverter designs are compared with this research.

How a battery storage system is able to counteract phase unbalance?

Counteracting phase unbalance through an inter-phase power transfer capable inverter, even more so than adding reactive power control, improves the performance of battery storage systems. Storage is considered a key technology in the evolution of the power system .

Do unbalanced inverters increase grid losses?

It is seen that the unbalanced inverter designs Inv 3 and Inv 4 manage to equalise the existing voltage unbalance in the peaks. Reactive power control capable inverters only increase the grid losses when used for voltage regulation (row 13). Row 14 shows that the available budget is fully used for all solutions except inverter-only solution H.

Can a battery storage system be based on a low-voltage grid?

Internal losses and losses in the grid are quantified for the different designs. Modelling a battery storage system purely as a finite source/sink of active power in a low-voltage grid, strongly underestimates the potential because of the existing phase unbalance.

What are the decision variables for inverter design?

The decision variables for design are the nominal inverter apparent power rating , the nominal battery capacity Enom, the effective battery capacity Eeff and the nominal dc bus power rating . The decision variables for control describe the power flow at each time step k through each phase p of the inverter: .

How many inverter designs are there?

Therefore four inverter designs are compared with this research. The most basic inverter model assumes only symmetric active power exchange; the most advanced inverter model allows interphase active power transfer and reactive power control.