How to draw a combined efficiency map

Hi expert,

I have two effiency maps, one for engine and one for generator and their operating curves like below. I want to obtain the maximum efficiency data, that is when speed from 0~600 rad/s, torque = the smaller value of maximum torque of genrator and engine(torque limitation), and effiency = efficiency of genrator * efficiency of engine.

The data file sizes are:

w_eg_row: 1*9 genrator speed

T_eg_col: 15*1 generator torque

eta_EG_map: 9*15 efficiency of generator

T_EG_max: 9*1 maximum torque versus speed

w_ce_row: 1*15 genrator speed

T_ce_col: 1*16 generator torque

eta_ce_map: 16*15 efficiency of generator

T_ce_max: 1*15 maximum torque versus speed

I don't know how to process the data to get the result. Could you please provide the code?

[xiaohan]

Add all the data files

Answer 1

[Aastha]

Hi @xiaohan,

As I understand, you want to plot combined efficiency maps using the data you provided. Kindly refer to the steps mentioned below to accomplish this:

1) You can use the "contourf" function in MATLAB to generate a filled contour plot. You can refer to MathWorks documentation of “contourf” function for more information on it.

https://www.mathworks.com/help/releases/R2024a/matlab/ref/contourf.html

2) You can use the generator torque variable “T_EG_col” as the x-coordinates and the generator speed variable “w_EG_row” as the y-coordinates to visualize the generator efficiency variable “eta_EG_map”. This can be achieved using a contourf plot, where efficiency is displayed as a function of generator torque and speed.

contourf(w_eg_row, T_eg_col, eta_EG_map');

3) Add a title, x-label, and y-label to the plot using the "title", "xlabel", and "ylabel" functions in MATLAB.

4) To enhance visualization, you can add a colour bar using the "colorbar" function. For more information on the “colorbar” function, you can refer to the link of MathWorks documentation mentioned below:

https://www.mathworks.com/help/releases/R2024a/matlab/ref/colorbar.html

5) Finally, you can plot the maximum generator torque as a function of the maximum generator speed using the "plot" function. To improve readability, set the line width to a bolder value and use blue colour by specifying the LineWidth name-value argument.

I hope this is helpful!