| 摘要 |
<p>1. Device for the determination of the useful mechanical power supplied by an asynchronous electric motor (M), characterized by means (SV, Mu, SG, Sl) for determining the mean power absorbed from the supply mains by a means (R) for measuring the current in one phase, by elaborating a single phase voltage from the voltages between two phases (U13 , U23 ) and by integrating the product of said current and said voltage, and first means (CO, SV) for subtracting from said product, before said integration, a quantity which is a function of the square of said current, second means (TR, RF, KU) for subtracting from said product, before said integration, a quantity which is a function of said voltage, and third means (AS, P2 ) for subtracting from said product, before said integration a quantity selected such that, when the motor is rotating under off-load conditions, the result of said integration is zero.</p> |
