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The dq transform is mostly used in the analysis of synchronous machines. The reference frame is fixed to the synchronous rotor. The d-axis is aligned with the magnetic field of the rotor and th q-axis is orthogonal to the d-axis and the rotation. You can imagine yourself rotating inside the machine, rotating at synchronous speed. It makes it simpler to ...


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how can I increase speed and decrease torque keeping watts same. Please explain for dc and bldc motor. Brushed or brushless DC makes no difference, the principle is the same. When the rotor/armature is spinning the motor acts as a generator, producing a voltage proportional to rpm (Faraday's Law). This voltage opposes the supply voltage. The difference ...


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The speed of a d.c. motor is given by $$ N = \frac { V - I_a.R_a}{kφ} $$ where 'V' is the applied voltage, 'Ia' the armature current, 'Ra' the armature resistance, 'k' a constant based on the number of poles, the number of conductors and number of parallel paths in the armature and 'φ' the flux per pole. That speed could be either increased or decreased ...


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The voltage producing eddy-currents in electric machinery and transformer laminations does not seem to be discussed in electric machinery and transformer texts. Where the lamination insulation is discussed, the focus seems to be on the mechanical properties of the material and maintaining material integrity. The implication seems to be that the voltage is ...


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