Table 2 lists all the state variables of the Storage element. The state variables can be monitored by setting a monitor for the Storage element in mode 3.

Table 2: State Variables of the Storage Element

State Variable

Description

kWh

Stored Energy in kWh.

State

Storage state. 1 for discharging, -1 for charging and 0 for idling.

kWOut

Power flowing out of the element, in kW. It is a result from the power flow. For discharging state.

kWIn

Power flowing into the element in kW. It is a result from the power flow. For charging and idling states.

kvarOut

Power flowing out of the element in kvar as a signed-value. Positive for vars generation and negative for vars absorption.


DCkW

DC power flowing into the storage inverter in kW at the DC side of the inverter as a signed-value. Positive for power flowing into the grid and negative for power flowing into the Storage element.

kWTotalLosses

Total losses in kW.

kWInvLosses

Inverter losses in kW.

kWIdlingLosses

Idling losses in kW.

kWChDchLosses

Charging and discharging losses in kW.


kWh Chng

Energy variation from the last time step, in kWh. Corresponds to the power that effectively charges/discharges the storage medium/battery multiplied by the time step length.

InvEff

Inverter efficiency.

InverterON

Flag indicating the inverter status. See [3].

Vref

Reference voltage used by the voltage-dependent InvControl function- alities. Equal to 9999 if there is no InvControl controlling the Storage element. See [3].

Vavg (DRC)

Average voltage of the moving window used in InvControl’s DRC func- tion. Equal to 9999 if there is no InvControl controlling the element. See [3].


VV Oper

Flag variable that indicates the status of InvControl’s Volt-Var function operation. Equal to 9999 if there is no InvControl controlling the element. See [3].


VW Oper

Flag variable that indicates the status of InvControl’s Volt-Watt func- tion operation. Equal to 9999 if there is no InvControl controlling the element. See[3].


DRC Oper

Flag variable that indicates the status of InvControl’s DRC function operation. Equal to 9999 if there is no InvControl controlling the element. See [3].


VV DRC Oper

Flag variable that indicates the status of InvControl’s VV + DRC function operation. Equal to 9999 if there is no InvControl controlling the element. See [3].

kWDesired

Nominal power desired or requested by the dispatch mode selected, in kW, if there is enough energy capacity left. Otherwise, it is 0.

kW VW Limit

Active power limit imposed by Volt-Watt function, in kW. See [3]. Equal to 9999 if the function is disabled due to inverter status.

Limit kWOut Function

Active power limit imposed by “Limit DER output function”

(%kWRated × kWRated), in kW. See [3].

kVA Exceeded

Flag indicating if inverter kVA rating has been exceeded. See [3].