Week 6 Fuel cell powered vehicle model

Fuel Cell Battery Model Explation :

Here we singal ramp signal as fuel flow rate .The flow rate take the input as stack current.
we are using sample hold block for this we are connecting flow rate equation ,another input signal we connecting to compare the flow rate with time 10 sec ,with edge decter , if flow rate is more than given rate ,the sample hold block trigger ,othertwisre untill it holds ,it next level trigger occurs ,then it will give ramp flow rate.here only we are talking flow rate output.we are taking here swallow water flow.

switch block can change the flow rate after some time .we limiting the flue rate at 85 with saturation block.

the stack fuel cell using ,to match the stack voltage and load voltage balance we are using Boost converter ( DC - DC Converter ).

PEM fuel cells are good energy sources to provide reliable power at steady state, but
they have a slow response. This is mainly due to their slow internal electrochemical and
thermodynamic responses . In order to optimize the fuel cell system performance, a fuel
cell DC-DC converters is needed to develop for various applications. Another important issue is
the need for appropriate control of fuel cell DC-DC converter which can regulate the power flow
and automatically adjust output voltage of the converters to avoid rapid load voltage variations,
which may lead to a reduction of the power quality of the system.

The load varies to the duty cycle .

here we using switch as a selector ,the control the voltage we using the integrals.

Here dc to dc converter we using inductor purpose of continuous voltage ,connecting parallel to capacitor ,to eliminate the ripple factor what we get in the load .

here we taking the outputs from the fuel stack are Utilization ,state efficiency ,state consumption,fuel flow rate in scope 1.

In scope 2 we talking the output fuel current ,fuel voitage ,Dc bus current ,Dc bus Voltage.

The Explanation of curves :

The first plot :The fuel flow rate wil start at 50 ,after 10 seconds it will change at 10 to 13.5 sec its was a ramp .initial it was 50 .it increased from 50 to 85.

The second plot utilization : The air is yellow ,magneta is hydrogen flow rate increased air will

THE third plot :state consumption (ipm) air yellow ,fuel Magneta ,

The last plot : State efficiency at flow rate increased the voltage increasd ,current also changed ,so efficiemcy come down ,at higher flue rate efficiency will be low.

inorder to not control fuel rate correct effciency may effect

CURVES of scope 2 :

The fuel voltgae has set to 45 before the start the fuel rate ,Due to RL load the expoential decade of voltage .
Same as after 10 sesc the voltage increased the cureent decreased.
The output load cannot experienced a transisent due controlled is involved , due to capacitor involved in parallel.
The dc voltage cannot allowed any transisent more than 100 because we using the proportional controller,a small spike is there .

AS well as dc current may occur a littllle bit spike occurs after 10 sec .

Change in fuel flow rate :

Here the fuel rate is 1 ipm so ,the result is like this it will start 20 before after 10 sec it increased to 60,

The fuel rate is less the state of efficiency will be more .

Fuel flow rate at 20 :

the flow rate o to 4 at 2 sec after increasesto 45 s still 10 sec after increases to 85 andit will be constant

The utlization :

starting o to 100 slowly increasing at 8 sec decreasing and constant at 50.( hydrogen)

it will be constant over all but at 8 sec decreases and goes to constant (oxygen)

stack consumption :

fuel is zero no consumption .

air before it will zero at 8 sec increases and comes to zero.

stact efficiency:

fuel flow rate is more ,over all efficiency is will be less.