What are WP+, WP-, and WP regarding watt-hour measurements?

WP- and WP+ will show the direction of Power Flow. An example would be WP+ as Charge, and WP- could be Discharge. This could be DC or AC. Also, in an AC circuit with a switching type power supply or a motor drive, we can see some WP- due to the harmonics. This WP- can lower the performance of the power supply and can cause reverse torque in a motor causing heat and lower motor performance. The engineer could use this WP-, or negative harmonic current, to improve the design of the circuit, or to design filters at the amplitude or frequency of the negative component. With the integrator, WP is the sum of WP+ and WP-. If you divide out the Time from the WP, you can get a Watt reading close to the Watt measurement in the Normal Mode. Normal Mode Watt measurement is a instantaneous value. WP from the integrator is an average value over the integration time. Therefore these values could be different.