Energy from Power

Question

I am working in MATLAB and I have 2 arrays. Current and Voltage flowing in a capacitance when I connect and disconnect it from the voltage. Of course I have a time_stamp vector in which there are all the samples of time at which I made the measurements.

I want to plot the power and energy associated to those arrays.

For the power I just need to do:

z1 = plot(time_stamp_ms,measured_voltage.*current,'-b','LineWidth',1);

Right?

Instead, how can I do to plot the energy?

Thanks for your time.

Answer 1

I think your power looks right. For energy, it's just power multiplied by time right so:

dt = diff(time_stamp_ms);
power = measured_voltage.*current;  
energy = dt.*power(2:end);

well this gives the energy used between each time step. If you wanted the cumulative energy then:

energy_cum = cumsum(energy)