Furthermore, the presence of stator slot openings causes a variation of the magnetic field in the magnets, this component of rotor eddy-current loss being dependent on the width of the slot openings and the pole/slot number combination.
- If you can get one big hole for all the cables, then job done. If not, by cutting 2 slots between the holes, you will stop the eddy currents from 'circulating'. Think of it like a break in the circuit.
- Equivalent current sheet model of one coil in slots. (a) Cross sectional area of SPMSM. (b) Stator current assumed to be on the slot opening as a current sheet. (c) Magnitude of stator current distribution. Eddy Current Loss and Temperature of the Magnets 1289.
What is Eddy Current?
The literal meaning of Eddy is a circular current. Thus the word itself means current having no definite circular loop. Gators den casino port allen la number. Eddy current is defined as the induced current on the surface of conductor in little loops or eddies due to changing magnetic flux. To better understand the concept of eddy current, let us take an example.
Furthermore, the presence of stator slot openings causes a variation of the magnetic field in the magnets, this component of rotor eddy-current loss being dependent on the width of the slot openings and the pole/slot number combination.
- If you can get one big hole for all the cables, then job done. If not, by cutting 2 slots between the holes, you will stop the eddy currents from 'circulating'. Think of it like a break in the circuit.
- Equivalent current sheet model of one coil in slots. (a) Cross sectional area of SPMSM. (b) Stator current assumed to be on the slot opening as a current sheet. (c) Magnitude of stator current distribution. Eddy Current Loss and Temperature of the Magnets 1289.
What is Eddy Current?
The literal meaning of Eddy is a circular current. Thus the word itself means current having no definite circular loop. Gators den casino port allen la number. Eddy current is defined as the induced current on the surface of conductor in little loops or eddies due to changing magnetic flux. To better understand the concept of eddy current, let us take an example.
Suppose a metallic plate is rotated in the magnetic field as shown in figure below. Lets us draw an imaginary loop on the surface of plate.
As the plate is rotated into the magnetic field, the flux linkage through the imaginary loop changes, due to which an induced current start to flow in the loop. We can draw a number of such imaginary loops on the plate and therefore current is induced on the surface of the plate in a variety of paths. This current is called Eddy Current. The direction of this current is found using Lenz's Law. The basic idea is that we do not have a definite conducting loop to guide the induced current. The system itself looks for the loop on the surface along which Eddy Currents are induced.
Electromagnetic Damping
Eddy Currents Loss
Because of such eddy current in the metal plates, thermal energy is produced in the plate. This energy here comes at the cost of kinetic energy of the moving plate and hence the metallic plate is slow down. This is the basic concept behind the electromagnetic damping. Now you may ask how to reduce this electromagnetic damping?
Eddy Current Slots Poker
Your obvious answer will be to reduce the eddy current. Well, but how can we reduce this current? To reduce, we need to reduce the path for the flow of such current. To reduce the possible paths we cut slots in the plate. This help in reducing the number of circular loops along which such current can flow. Thus the loss of energy due to eddy current is reduced and hence the electromagnetic damping is reduced.
