Electric Range

This example demonstrates a model used for determining the range of an electric vehicle. The vehicle is represented by a battery, the electric loads of the vehicle, and an electric machine connected to a simple 1D chassis. The driver controls the vehicle speed to follow a repeated sequence of the WLTP cycle (class 3).

Electric range

The range of the vehicle is here defined as the distance that the vehicle travels, when driven according to a repeated sequence of a specific drive cycle. The simulation starts with a fully charged battery, at 90 % SoC. And a monitor in the battery has been configured to stop the simulation when the battery is depleated at 10 % SoC (configured in the Limits tab of the battery model). Note that the SoC here defines the full capacity of the battery. This assumes that the capacity of the battery has been parametrized in this way, and that we only allow using a limited window of this capacity. If we instead have parametrized the usable capacity of tha battery, we would initialize the battery at 100 % SoC and stop the simulation at 0 % SoC.

Drive cycle

A driver model (speed feedback controller) is used to control the vehicle speed according to follow the speed profile determined by the WLTP cycle. The plot below shows the reference speed for the first cycle, and the actual measured speed of the vehicle. The measured speed follows the reference more or less. If we look closely, we can see that the speed becomes negative for a short moment before the vehicle reach regions of standstill. This is because braking of the vehicle is only applied via the electric machine (no friction brakes), and the driver is not configured to avoid these "undershoots".

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The driver provides a reference torque for the machine connected to the wheels of the vehicle chassis. The torque reference is provided to the machine as a signal via the system control bus, using a signal adapter (more about this in the User's Guide). Note that the machine id is specified in the adapter to address the machine on the system control bus.

The plot below shows the reference torque together with the measured rotor torque of the machine. We can note that no limits are reached that limits the output torque. Both torque and power limits have actually been disabled in the core model of the machine. The only limit that is present, is a current limit of 1000 A.

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Range (distance)

The plot below shows the position of the vehicle versus the SoC of the battery. We can see that the vehicle has traveled 272 km when the battery is depleted.

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Energy losses

The plot below shows the energy lost to heat in the battery and the machine, as well as the energy lost to the additional loads. Note that the loads component has been parametrized with a loss factor of 100 % (k_loss=1) so that all of the consumed energy is reported as losses (dissipated as heat).

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