Battery

The Battery component is one of several battery components available in Typhoon HIL Schematic Editor. It is a component focused on easy parametrization and representation of multiple battery types, and is often paired with a Battery inverter component. If you need more flexibility in parametrizing your battery, or you would like to represent a more advanced battery model (such as for BMS testing), consider using the newer Battery Cell component instead.

The Battery component is implemented as a controlled voltage source and a series resistance. The voltage source is controlled by a lookup table that is automatically modified by changing the battery type. In order to get information regarding the battery's state of charge during simulation in HIL SCADA, it is necessary to check the State of charge output (SOC), and to connect the battery to the Probe, which adds the SOC signal (in percentage) to the list of analog signals in HIL SCADA.

Table 1. Battery component in Schematic Editor

component	component dialog window	component parameters
Battery		General Battery type Nominal voltage [V] Capacity [Ah] Initial state of charge [%] Full charge voltage [%] Nominal discharge current [%] Internal resistance [Ω] Capacity at nominal voltage [%] Capacity at exponential zone [%] Voltage at exponential zone [%] Battery discharge curve preview button Signal processing State of charge output (SOC) Use signal processing Look up table Execution rate [s] Extras Signal access

Generic battery model

The battery model is implemented in the Typhoon HIL toolchain using a generic set of equations that describes the behavior of the battery.

There are 3 points at the battery's discharge curve (Figure 1) that are used by the equations:

1. Fully charged battery (Vfull, Q - rated capacity of the battery)
2. End of exponential zone (Vexp, Qexp)
3. End of nominal zone (Vnom, Qnom)

Figure 2 presents a schematic diagram of the battery model. It consists of a controlled voltage source (E) and a series resistance (Rbat). The controlled voltage source is managed by the discharge state of the battery. The battery voltage is a function of the discharge state (it) according to the following formula:

where:

• it: is the discharge state of the battery, defined as: $it=\underset{0}{\overset{t}{\int }}ibat*dt$
• A: Voltage drop during the exponential zone: $A=E_{full}-E_{exp}$
• 3/B: Charge at the end of exponential zone: $B=\frac{3}{Q_{exp}}$
• K: Polarization voltage: $K=\frac{(E_{full}-E_{nom}+\mathrm{A}\mathrm{*}\left({\mathrm{e}}^{-\mathrm{B}\mathrm{*}{Q}_{nom}}-1\right))\mathrm{*}(\mathrm{Q}-Q_{nom})}{Q_{nom}}$
• E0 voltage constant: $E_0=E_{full}+K+R_{bat}*i-A$ , where i is the rated discharge current.

The series resistance is calculated by assuming the battery efficiency is 99.5% as follows:

Tab: General

If you need additional parameters, then choose the User defined option for Battery type. This enables additional parameters that allow you to define the battery's SOC curve in detail.

The Preview SOC Curve button will graph the characteristic SOC curve of a selected battery based on the previous equations (Figure 4).

Tab: Signal Processing

If the State of charge output (SOC) property is checked, an additional signal processing output port on the battery model will be added (Figure 6), which outputs the current state of charge of the battery. The Execution rate property will be enabled in that case, which determines the execution rate of the signal processing components.

If the Use signal processing Look up table property is checked, the entire battery will be modeled with a Signal Processing lookup table (Figure 7). The initial State of Charge is set in HIL SCADA through the Scada Input property Name.InitialSOC. It can be changed during the simulation runtime. In this case, the Execution rate property will be enabled, adapting the simulation to the execution rate of the signal processing components and not by the time step defined in the circuit solver settings.