Hi, I guess this post is too old, so I am not sure if you are still intrested in the topic or got the answer elsewhere, but I just signed up and joined the forum since I was searching in the same topic (I am working on a power quality monitoring software myself). For your power factor problem, first of all, the power factor you are calculating by finding the phase shift between the fundamental frequencies of voltage and current is called the Displacement Power Factor, and it is different from the True Power Factor, which is simply the ratio: True Power (Watts) / Apparent Power (VA), which can be done by multiplying the V and I signals (point by point), and calculating the average power to get the true power, and multiplying the rms values of V and I to get the apparent power value.
But anyhow, if you are still intrested in the Displacement Power Factor, first of all, you used an Express VI to generate the signal, but you used a VI that uses waveform datatype for tone extraction, so try converting the dynamic data type into a single waveform using "from DDT" VI. But your real problem is simply a sampling rate problem, your using a signal source sampled at 10000Hz and you are reading them as 999 samples at a time, so you are not getting an integer number of cycles, and so the phase you are getting is constantly changing, and so is the power factor, so try changing the number of samples to 1000 for example, and it would work. I got a constant value of 0.423 at your settings
As for the transients, i was actually searching for this topic, and am trying to find models for induction motors or other machines that experience transients so as to use the model to introduce the effects needed, but still no luck with that. Anyways, i hope that helped.
