| 摘要 |
Procedure and device for measuring power loss of direct current motors with independent and parallel excitation (MJS), is achieved by connecting brushes (Č) set at the ends of the shaft (V) of the machine rotor, insulated conditioner (IKU) for measuring alternating voltage (u = u(t)) between the brushes set at the ends of the shaft of the motor and other components. Therewith, precise definition of technical problem of measuring the loss of power (PY) is solved by positive technical and economic effects in comparison to the known solutuions comprised in the state-of-art. Measuring gives instant values of alternating voltage (u = u(t)) at the chosen intervals from (10-50) μs, which is, as a complex periodic function of time, expand into Fourier series as harmonics, and then by a quotient of the predominant harmonic and the chosen measuring time determined is frequency of that voltage at unknown and nominal loading, (ƒ) and (ƒn), and finally according to the equation (16) the required power losses (PY) of the motors (MJS) under consideration. This is applicable when number of pole pairs (p), nominal torque (Mn), speed of idle run (n0) and used electric power of that engine (P1) are known.
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