Final Project: Electric Rickshaw modelling

- Via one semiconductor switch and one freewheeling diode.

- Via two freewheeling diodes.

- Via two semiconductor switches and one freewheeling diode.

- The first and third options are sometimes referred to as a synchronous operation.

- The signal at the REV port determines the polarity of the output. If the value of the signal at the REV port is less than the value of the Reverse threshold voltage parameter, the output has positive polarity; otherwise, it has negative polarity.

- For this model, the simulation model is kept average in order to reduce the overall simulation time. If it is kept at PWM the time will be longer, Regenerative braking is activated and load current characteristics are kept smooth.

- The above block showing the necessary parameters for the H bridge block.

- Control voltage source:

-  The Controlled Voltage Source block represents an ideal voltage source that is powerful enough to maintain the specified voltage at its output regardless of the current flowing through the source. The output voltage is V = Vs, where Vs is the numerical value presented at the physical signal port.

- This block is connected to the PWM controller in order to provide a constant voltage supply and also in order to generate the energy while braking that is regenerative braking. The same DC motor will act as a generator for some time and act as a generator.

- Drive cycle:

- The Drive Cycle Source block generates a standard or user-specified longitudinal drive cycle. The block output is the specified vehicle longitudinal speed, which you can use to:

- Predict the engine torque and fuel consumption that a vehicle requires to achieve desired speed and acceleration for a given gear shift reference.

- Produce realistic velocity and shift references for closed-loop acceleration and braking commands for vehicle control and plant models.

- Study, tune, and optimize vehicle control, system performance, and system robustness over multiple drive cycles.

- There are several drive cycles that automakers will be using as predefined input.

- As an input, a spreadsheet and a signal builder block can be used as well.

- A multi-input port is used in order to provide more number of inputs as per the requirement.

- Drive cycle by the user:

- As per the requirement a drive cycle has been taken to match the Indian road conditions and the file is attached below. 

 - Longitudinal Driver: 

- The Longitudinal Driver block implements a longitudinal speed-tracking controller. Based on reference and feedback velocities, the block generates normalized acceleration and braking commands that can vary from 0 through 1. You can use the block to model the dynamic response of a driver or to generate the commands necessary to track a longitudinal drive cycle.

- This driver will take the inputs from Vehicle feedback speed and its input will be Vehicle Reference from the input parameters.

- In its simple way targeted speed is a vehicle reference and vehicle feedback is actual speed and the difference between them is the error.

- This block is working on a PI controller and has all the necessary input parameters. This block gives an Accelerator command and a brake command which aids in increasing the speed and applying the brakes.

- Signals will be coming out as 0 and 1 out of the driver and a converter is needed to connect it to the electrical part.

- Battery:

- The Battery block represents a simple battery model. The block has four modelling variants, accessible by right-clicking the block in your block diagram and then selecting the appropriate option from the context menu, under Simscape > Block choices:

- Uninstrumented | No thermal port — A basic model that does not output battery charge level or simulate thermal effects. This modelling variant is the default.

- Uninstrumented | Show thermal port — Model with the exposed thermal port. This model does not measure the internal charge level of the battery.

- Instrumented | No thermal port — Model with an exposed charge output port. This model does not simulate thermal effects.

- Instrumented | Show thermal port — Model that lets you measure the internal charge level of the battery and simulate thermal effects. Both the thermal port and the charge output port are exposed.

- A controlled current source is used which will discharge the battery depending upon the current taken by the motor.

- First, run using the drive cycle for Indian road conditions:

- As this cycle is already available in the Simulink environment, direct input is given and the model is run.

- Before running the model it is required to turn the temperature sensor on and the required steps are mentioned below.

- All the changes done in the model and the output plots are shown below.

Step to unhide the temperature sensor	DC Motor block input values.
Battery parameters	Output values of SoC, Current, and voltage.
Distance covered by the vehicle as per the requirement with given parameters.	Graph showing controller temperature and motor temperature. Maximum value obtained for a controller temperature is 349 and for the motor it is 335.
SoC graph reaching to 39% from 100% SoC.	Graph showing the behaviour of voltage during the run.

- 2nd run using the FTP75 drive cycle input by the user:

- As per the requirement a drive cycle equivalent to the actual Indian road condition has to be made and it is given as the input.

- All the changed and outputs are mentioned below.

As per the requirement, the FTP75 drive cycle is run and the result is as per the drive cycle.	For the given test the gear ration is 8.5
	From the graph, it can be seen that after some time the temperature for both the controller and the motor reaches a pick value and remains constant after that.

 

- 3rd run using Wide-open throttle:

- WOT means increasing the throttle position from its 0 positions to its full position. In this, the vehicle starts from 0 speed and reached to its maximum speed due to the full-throttle position. 

SoC after using wide-open throttle cycle.	Temperature generation in the controller and the motor.

 

- Result:

- Using the given cycle the vehicle covers a distance of 99.6 km with the given requirement like SoC and temperature generation.

- Also the temperature generation is within the range of 400 degrees C for both the controller and the motor.

- However, using the wide-open throttle cycle and FTP75 the results varies accordingly. 

- References:

- https://www.mahindraelectric.com/vehicles/treo-electric-auto/