MATLAB: Provide Duty Signal delay

MATLABpower_electronics_controlsimpowersystemssimulink

Hello,

I am trying to give three duty signal to a block. Such as D1+D2+D3=1. So what ever the combination of these duty is the total answer should be 1. I have used transport delay but it is not giving me accurate delay. You can see in screenshort.

My objective is to have variable duty (like it can be changed instaneously through a controller) and as soon as D1 end D2 should start which is then folled by D3=1-D1-D2

Can you please help me with this model. I am attaching model too. In screenshot the delay D3 is giving a slant which is not desireable. It should be like D1.

Best Answer

I would do something like this (.slx file is attached).

So the signals will be generated by each Pulse Generator. At each period, signal 1 will not be delayed, signal 2 will be present as signal 1 dies, and signal 3 will be present as signal 2 dies.

In the model, I put these blocks as a subsystem and put a mask over it. I hope that helps. Anyway, please check the output signal and the implementation under the mask to see if this is suitable for you.

Related Solutions

MATLAB: Can someone explain me on how this duty cycle work

Hi,

A duty cycle or power cycle is the fraction of a signal or system is HIGH. Duty cycle is commonly expressed as a percentage or a ratio. A period is the time it takes for a signal to complete an on-and-off cycle.

Hence, for the PWM Generator block we have to input duty cycle in terms of percentage.In order to do that for your model, first try to make the output (Vout / (Vout + Vin)) of your duty cycle subsystem to be in between 0 and 1.Then insert gain block with value 100 before PWM Generator block to convert to a percentage

MATLAB: Is there a way to have a variable pulse signal in Simulink 6.4 (R2006a)

Below is an example of how to implement a variable pulse in Simulink. It involves using the Pulse Generator block and a MATLAB file S-function. The S-function takes the desired pulse width (this could be coming from a controller) and uses SET_PARAM to change the PulseWidth property of the Pulse Generator block.

The example is feeding the desired pulse width into the S-function as a percentage of the Period property in the Pulse Generator block (i.e. duty cycle). You can alter the S-function if you want to feed in the exact width. This would involve adding commands to calculate the pulse width percentage as a function of the period and the desired pulse width.

The set_param command is done on line 272 of the S-function in the Outputs() function. Note there are no actual outputs from the S-function, it is just used to change parameters. Also note another set_param command is done in the InitializeConditions() function. This is to ensure a valid value of PulseWidth is in the Pulse Generator block at the start of simulation.

Here are a few helpful documentation links (You can copy and paste the commands below into the MATLAB command window to display the documentation):

set_param

web([docroot,'/toolbox/simulink/slref/set_param.html'])

Writing Level-2 MATLAB file S-Functions

web([docroot '/simulink/sfg/writing-level-2-matlab-s-functions.html'])

Pulse Generator

web([docroot,'/toolbox/simulink/slref/pulsegenerator.html'])

Pulse Width Modulator Generator

web([docroot,'/toolbox/physmod/powersys/ref/pwmgenerator.html'])

Best Answer

Related Solutions

MATLAB: Can someone explain me on how this duty cycle work

MATLAB: Is there a way to have a variable pulse signal in Simulink 6.4 (R2006a)

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