Contents
What is torque in AC motor?
Torque is defined as the force that gives rise to rotational motion. It is also the result of rotational motion. Torque (t) is equal to force (f) times the radius (r) through which it acts and the angle (Ø) at which the force is applied.
What is flux and torque?
Torque current is the portion of the total current to the motor that is in phase with the output voltage. Flux current, simplistically described, is the portion of the total current which magnetizes the motor. The efficiency of any motor will improve if more of the total current is in phase with the output voltage.
What is flux in AC motor?
Flux: The flow of current through a conductor creates a magnetic field. Magnetic flux: Magnetic flux is defined as the rate of a magnetic field flowing through a given conductor’s cross-sectional area. Magnetic flux field is generated by a permanent magnet within or on the surface of a permanent magnet motor.
What is the relationship between current and torque?
The increase in the torque on the motor shaft results in the linear increase in the armature current. It is also shown in the equation (8) from the previous tutorial. The current function I, depending on the torque M, shows that more current flowing through the motor will produce a higher torque.
What is current feedback torque?
Frequent and accurate current sampling is necessary to close the current loop, which is the foundation for a sound motion control system. Current feedback is also used for torque control since output torque is proportional to motor current.
What is saliency ratio?
“saliency ratio” = Ld / L The d-axis is when the rotor is aligned with the poles. It is also the orientation with highest inductance. The q-axis is when the rotor is aligned with the gaps. It has the lowest inductance. It can be shown that reluctance motors work best when you maximize the saliency ratio.
How is the torque of an AC motor determined?
Motor current. In an AC motor without a permanent magnet, the flux amplitude is set by the ratio of the applied voltage to the frequency. The torque is the product of the flux and the torque-producing current, i.e. the component of current which is in phase with the voltage.
What is the sum of torque and flux?
It is said that vector sum of flux and torque current equal to total current drawn by the motor but there are also some currents flowing due to copper losses and rotor leakage inductance. In my opinion, the total current must equal to vector sum of core losses current + torque current and rotor leakage inductance current + flux current ?
The torque is the product of the flux and the torque-producing current, i.e. the component of current which is in phase with the voltage. In DC motors and AC induction motors, the magnetising current is usually constant regardless of torque, unless a special energy-saving control is applied at reduced torque.
What causes the flux current in an induction motor?
The magnetizing current or “flux current” is “imaginary current” in AC circuit analysis terminology. The rotor and stator leakage inductance cause voltage drops rather than additional current.