Project 1

Project 1

Power Sharing:

Aim:

To create a Simulink model for the given flowchart. The input to the model should be power demand. To load .mat file in the workspace. To display the fuel cell power, battery power and fuel cell operating state against time.

Software Used:

• MATLAB/ Simulink

Blocks Used:

• Constant
• Slider gain
• In
• Out
• Switch
• Less than
• Greater than
• Goto
• From
• AND
• Scope

Model:

Subsystem:

Workspace:

Procedure:

• The input power is given by the slider gain.
• The parameters such as P_max (maximum operating value of fuel cell), P_min(minimum operating value for fuel cell), SOC_min (minimum SOC value) and SOC_init (initial SOC value) are loaded in the workspace.
• If input power is negative and the soc is less than 0.9, then the negative power is given to battery for charging. This can be obtained by using switches.
• If the SOC is greater than 0.9, then the zero power is given to battery.
• If the input power is positive and is less than minimum operating value of fuel cell i.e.,30000W, then check the Soc value of the battery.
• If the SOC is greater than minimum value of SOC, the positive power less than 30000W is met by battery.
• If the power is above 30000W and less than maximum operating value of fuel cell i.e., 60000W, then this power is met by fuel cell.
• If the power is greater than 60000W, then this peak load has to be supplied by the battery according to the flowchart.
• It is not efficient to operate the fuel cell below the minimum operating value and above the maximum operating value.
• So, these values has to be met by battery according to the flowchart.
• This condition can be obtained by switches, less than, greater than and AND blocks.
• The model is simulated for infinite time for real time changing of power demand.

Explanation:

If the power is demanded, that power has to be supplied by the vehicles either by using the primary energy source or by secondary energy source. In this flowchart, the given vehicle is hybrid fuel cell vehicle. The primary energy source is fuel cell and the secondary energy source is battery. If the energy required by the vehicle is very less i.e., less than minimum operating speed of fuel cell vehicle, then the demanded has to be met by battery. Because fuel cell has the certain range operating range to be operated in optimum efficiency and power. If fuel cell is operated beyond that range the efficiency of the vehicle is poor. If the power demanded is within range, then fuel cell is used to power the vehicle. If sudden peak power is demanded, i.e, beyond maximum operating speed of the fuel cell, it has to be supplied by the battery.

Output:

Scope:

Summary:

• From the above plot, it is observed that whenever the speed is above maximum operating power, the power is met by battery.
• When the speed is in operating range of fuel cell, the power is met by fuel cell.
• When the power is met by fuel cell, the fuel cell operating state is 1, it indicates running mode.
• Whenever the power is met is by battery, the fuel cell operating state is 0, it indicates standby mode.
• When the peak power is required, it is met by battery. It is visualized in the battery.
• If the negative power is given, it is given to the battery for charging.
• Whenever the fuel cell is operated, the battery goes to standby mode.