Coil Span or Coil Pitch Coil of dc machine is made up of one turn or multi turns of the conductor. In order to resolve this kind of problem and eliminate the cogging phenomena, we present the mode of fraction slot winding.
The end winding needs to enlarge also. In the mean time, it resolves the cogging problem of the motors and effectively improve the winding factor of high-order harmonic waves of back E. Due to the unsymmetrical characteristics between the rotor's magnetic pole and the stator's teeth, the cogging phenomena is greatly reduced. We take a look again at the winding method of the 4-pole, slot fraction slot motor, the connection-mode is as follows: Pole Pitch Definition of Pole Pitch The pole pitch is defined as peripheral distance between center of two adjacent poles in DC machine.
The connection mode is as follows: As we have seen that, pole pitch is equal to total numbers of armature slots divided by total numbers of poles, we alternatively refer it as armature slots per pole. It contains three phases, A, B and C. But because english harbour casino free slots the magnetic action, it results in very significant cogging phenomena, and the winding factor of its fundamental wave becomes maximum.
Slot winding winding factor for the high-order harmonic waves can be improved. Note that, in this chart, the 9th, 18th and 27th, slots are blank slots, that is, to remove the coil of the long pole-pitch of a custom-used fraction slot winding method.
The winding is rather simple. The connection mode is as follows.
The number of stator slot of the motor is not an integer multiple of the number of poles, thus the slot winding of stator slots, to which each individual pole corresponds, is a fraction. Thus, the total terminal voltage of the coil will be nothing but the direct arithmetic sum of these two emfs.
Coil Span or Coil Pitch
Hence, by adopting the 4-pole, slot blank slot winding method, the cogging torque is small, winding is simple and the repress effect is good for high-order harmonic waves. As shown in the figure, the number along the outer layer represents the ordinal number, from the first slot through the 24th slot.
Both of these winding can result in phase balance. It can also lower the high-order harmonic waves of the back electromotive force. A method for winding a stator of a brushless motor structure, comprising: But since their winding factors of the 3rd and 5th harmonic waves are larger than those of the blank half-slot 4we had better adopt the blank half-slot winding method when it comes to an air gap magnetic flux design and we are unable to effectively lower the generation of the high-order harmonic waves.
A method for winding a stator of a brushless motor structure as defined in claim 1, wherein: If q equals 1 and "-" the minus sign is used, then there will have empty phase zone generated. Eliminate the cogging phenomina of the motor, and possess the low cogging torque characteristic.
Its connection mode is as follows: Also, the selection of the number of stator slot is a fraction slot, that is, the corresponding slot number of each individual pole is a fraction.
This number is known as coil span. One is the integer slot winding method, the other is the fraction slot winding method. Here we compare the winding factors of the two practical examples of our invention with those of the two custom-used winding methods, we end up with the characteristics as shown in the following table.
How to make 36 slot three phase motor 4 pole chain winding
But also because of this, the winding operation becomes very complicated. It can lower the high-order harmonic wave in the condition that the air gap magnetic flux is not a well distributed closest casino to muskegon michigan wave. It is an original work of technical thoughts and has never been found in any publications.
A method for winding a stator of a brushless motor structure as defined in claim 3, wherein: It also maintains double layer winding method with two phases, but the neighboring slots have coils removed from the half-slot.
The winding of each phase contains 8 stator slots including 4 outlets and 4 inlets slots respectively. The selection of the number of the stator slots is such that the corresponding stator's number of each pole is a fraction.
A single turn coil will have one conductor per side of the coil whereas, in multi turns coil, there will be multiple conductors per side of the coil. Thus, what is installed in every slot is a coil with single phase. US Stators incorporating blank winding slots for a permanent magnet brushless motor and method of winding thereof Expired - Lifetime USA en Priority Applications 2.
From the summary as stated above, we can see that this invention "The winding methods and their structures of the stator's blank slot of a permanent magnet brushless motor" possesses high enterprising value.
If the coil span is less than the pole pitch, then the winding is referred as fractional pitched. It won't be adequate although it can still keep phase balance. It can also degrade the cogging phenomena of the motor, that is, it has both the advantages of the fraction slot winding and the integer slot winding methods and at the same time, resolves the unavoidable shortcomings of these two custom-used winding methods.