Lawrence, Prof, I am working on a short document that may help with this testing. Below is a preview:
Lawrence, your scopes do not have the integral function, but for obtaining the circuit COP, that is not a necessity actually. What matters most is the ability for the scope to perform "multiplication" and "mean" averaging, which your model does do.
The fact that you have two scopes at your disposal makes the COP calculation a little easier.
While I fully advocate and strongly encourage the use of differential and current probes for obtaining these type of power measurements, it may be viable to examine the potential of using the much less favorable method employing passive scope probes.
The first objective then when using the oscilloscope method is to ensure that your scope and passive probe combination can obtain an accurate measurement at the frequencies and rise/fall times present with your device. The following is a step-by-step process which should determine if your scope and passive probes are up to the task.
In essence, the process involves testing with a square generator and resistive load. Current and voltage is measured, multiplied together, then a "mean average" applied to the wave form in the scope. This will allow you to read off directly the real power into the load resistor. Then you compare this with the theoretical computation (very easy to perform) of the real power. If they match well, it may be possible to apply a similar technique (which I will outline in the document) to measure both the input and output powers in question, and a simple division of the two produces the COP value for the circuit.
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