Simscape Battery - A Three Minute Tour From Cell To System
Simscape Battery™, a new product in the Simscape™ portfolio, has been developed to provide a technology development framework that is assembled specifically to create a bridge between cell and system. The bridge directly supports upskilling as well as design exploration and design rigor, meaning you can navigate the battery system technology development cycle rapidly and with confidence. See the design workflow in action in this three-minute tour, where we develop a battery pack from individual cells, add battery management and thermal management, and finally simulate and analyze the system.
Published: 16 Nov 2022
In this video, we are taking a 3-minute tour of Simscape Battery. We start in Matlab with the battery pack builder, where we define the format and geometry of an individual cell. From the cell, we define a parallel assembly. And from the parallel assembly, we define the module. As we build our pack, we can define the model resolution that we want our Simscape model to have.
In this example, we'll model each parallel assembly as a single-cell model. We define a modular assembly before finally defining our full pack. From here, a single line of code will generate a Simscape model of your pack with the model resolution that you've chosen. Now, we have our pack model, let's build out our full system. We first add our pack with an electrical load.
Next, we had our ambient environment using thermal components and connect our ambient model to the ambient thermal port. Next, we add cooling. In this case, we're using a parallel channel cooling plate and thermal liquid components, which we connect to the cooling thermal port. Our physical system is now complete. So we now add the algorithms, starting with state of charge estimation.
In practice, we cannot directly measure state of charge. So we must estimate it from voltage, current, and temperature. Now, we add a state-of-health estimator, which is important for monitoring the remaining useful life of the battery pack. In this case, we estimate state of health from estimated terminal resistance. Now, we add the temperature control system, which controls the flow of coolant liquids through the cooling plate to regulate pack temperature.
Next, comes cell balancing, through which we equalize the state of charge of each cell. If this is not done, the cells will degrade at different rates and cell capacity will be reduced. Finally, we add a pack level of charge and discharge algorithm. This algorithm ensures that the pack state of charge is kept within specified limits. Voila, we now have a functional battery system. Now, we can simulate and analyze.
On the left, we can see measured state of charge and estimated state of charge or as we see. While SOC cannot be directly measured in practice, we can measure it in simulation. Note that the SOC starts at different values and then converges to the same value-- that cell balancing in action. Also note that the SOC level is off. That's charge limiting in action. I hope you enjoyed this tour. Thank you for listening.