Week-3 Challenge: ADVISOR Tool

Challenge:ADVISOR Tool

Objective:

To Use ADVISOR tool and simulate following:

1. For EV_defaults_in file. If cargo mass is 500 kg with all other default conditions, can the vehice travel for 45 km with FTP drive cycle ?

2.   In the above case, try changing the battery capacity and repeat the simulation.

3.   Perform gradeability test with PRIUS_Jpn_defaults_in file. Compare your results in table and conclude.

ADVISOR(Advance Vehicle Simulator):

ADVISOR, NREL's Advanced Vehicle Simulator, is a set of model, data, and script text files for use with Matlab and Simulink. It is designed for rapid analysis of the performance and fuel economy of conventional, electric and hybrid vehicles. Advisor also provides a backbone for the detailed simulation and analysis of user defined drivetrain components, a starting point of verified vehicle data and algorithms from which to take full advantage of the modeling flexibility of Simulink and analytic power of MATLAB.

Benefit of Advisor Are:

• Estimate the fuel economy of vehicles that have not yet been built.
• Learn about how conventional, hybrid, or electric vehicles use(and lose) energy throughout their drivetrains.
• Compare relative tailpipe emissions produced on a number of cycles.
• Evaluate an energy managment strategy for your hybrid vehicle's  fuel converter.
• Optimize the gera ratios in your transmission to minimize fuel use or maxmize performance,etc.

The Model Of Advisor Are:

• Mostly emprical,relying on drivetrain component input/output relationships measured in the laboratory, and 
• Quasi-static, using data collected in steady state (for exmaple, constant torque and speed) tests and correcting them for transient effects such as the rotational inertia of drivetrain components.

1. For EV_defaults_in file,if cargo mass is 500 kg with all other default conditions, can the vehice travel for 45 km with FTP drive cycle ?

Conclude your observations.

Considering the case for an typical EV.lets simulate EV_defaults_in an electric vehicle with following specifications.

In the above example, a battery electric vehicle is modelled with following specifications:

Energy storage: Lead Acid battery with 25 modules having 308 V as nominal voltage with 0.92 motor efficiency.

Motor:AC induction motor wizth 75kW.

Transmission: Manual

Drive: Front Wheel drive

Cargo Mass: 500Kg

Next, we input the drive cycle called CYC_FTP which is 17.7 km long in distance. Hence in order to drain the battery completely to SOC = 0% for calculating the range of vehicle, 4 drive cycles are repeated, so that vehicle will travel 70.8 km in total and we can find out at what distance the SOC is 0.

In the above figure, first plot shows that drive cycle for which vehicle has travelled, the second plot shows the SOC fall with time, the third and the fourth graph show the power output according to the throttle condition.

Hence, after running the simulation, we can see that, the SOC becomes zero after approximately 2.5 drive cycles. As shown at the right hand side, the distance travelled by vehicle cannot travel 45km in a single charge.

2. In the above case, try changing the battery capacity and repeat the simulation:

In this case the same default conditions are taken that are initate in question 1 and battery capacity will changed for accelarating the vehicle that will increase the vehicle distance travel km.

-Increasing the battery capacity of vehicle.

So, inorder to achieve a range of 45km, 3 more modules of batteries have been added making the total modules to 28 and nominal voltage to 345V.

3.Perform Gradeability test with PRIUS_JPN_DEFAULTS_IN file compare your results in table and conclude:

Following is the model of toyota prius parallel hybrid vehicle. It uses battery and IC engine to power the wheels.As can seen from the figure, The differential is connected to motor and it is also connected to an IC engine via a device called as a power splitdevice.Power Split splits the power according to the throttle demands keeping the engine in maximum efficiency zone,providing additional power via battery and engine during aggressive conditions, charging the batteyr via a generator during conditions such as regenerative braking and preserving the energy efficiently.

Vehicle Specifications:

Powwer produced by IC engine : 43kW with fuel converter efficiency of 0.39

Battery Capacity : NMH(Nickel Metal HYdride) batteries have been used with 40 modules producing a nominal voltage of 308 V 

Generator(Regenarative): 15kW

Motor : Induction motor Producing power of 15kW with 0.84 efficiency

Transmission : CVT

Drive: Front wheel drive

Inorder to perform the gradeabiity test. We keep the grade value constant and  change the speed values to find the maximum gradeability at an optimum speed simulating for 10s.

Hence the simulation is run for gradeability test.

Following are the output results :

Case 1: Speed = 5kmph (8kmph)

Gradeability = 18.1%

Case 2 : speed = 15kmph (24.1kmph)

Gradeability = 26.4%

Case 3 : speed = 20kmph(32.2kmph)

Gradeability : 12.6%

Hence, speed of 15mph to 25mph gives highest gradeability value which makes them the optimum speeds of prius.