Week 9 Challenge

Complete the energy management strategy model with battery, UC and fuel cell for the positive power and distribute the power demand among these components. Set simulation stop time to 598 sec.

The output of the model should be the power request from UC, fuel cell and battery.

Answers:-

Regarding Energy Management Systems:

The automotive industry is currently undergoing a technological transformation in vehicle powertrains. In this context, hybrid electric vehicles (HEVs) emerge as a viable solution to address issues such as the low energy density of conventional power batteries and the limited driving range of purely electric vehicles (EVs). Various configurations of HEVs exist, each with its unique control strategies, production costs, and suitability under specific conditions. However, regardless of the configuration, the primary objective remains achieving comprehensive optimization of engine and motor efficiency to enhance vehicle performance metrics like fuel economy, emissions, and durability.

This objective is commonly pursued through the implementation of an Energy Management Strategy (EMS). EMS systems are responsible for load sharing, a crucial aspect of HEV operation. Depending on the vehicle's power demand, power requests from different energy sources—such as ultracapacitors, batteries, and fuel cells—are distributed accordingly, leveraging their respective power delivery capabilities.

Power Sharing:-

Fuel cells have a range of operating conditions to produce the required propulsion power. In this context, we consider a fuel cell capable of generating power within a range from a minimum of 23 kW to a maximum of 72 kW. However, to optimize fuel cell efficiency, it's observed that they operate most efficiently in a moderate power generation range, typically around 55 kW, as indicated by the polarization curve.

In terms of power distribution among components, batteries are preferred for lower power demand conditions, while ultracapacitors are preferred for peak power demands. The final power sharing scheme among the three components is as follows:

- Power ranging from 0 to 23 kW is drawn from the battery unit, based on its State of Charge (SOC) condition.

- Power between 23 kW and 55 kW is sourced from the fuel cell.

- Power exceeding 55 kW is drawn from the ultracapacitors, again based on their SOC condition.

However, if the SOC of the ultracapacitors is insufficient to meet the required power demand, power is drawn from the battery as a backup. Similarly, if both the battery and ultracapacitor SOC levels are insufficient, the only alternative power source available is the fuel cell. In such scenarios, power is drawn from the fuel cell as a backup.

It's important to note that operating under these conditions may result in reduced overall vehicle efficiency, as the fuel cell may not efficiently support both peak and lower power demands simultaneously.

Observations:-

+ve Power:-

-ve Power:-

Backup power

grasp for drive cycle

Conclusion:-

we have Completed the energy management strategy model with battery UC and fuel cell for the positive power and distribute the power demand among these components. and Seted the simulation stop time to 598 sec. The output of the model obtained by the power request from UC fuel cell and battery.