CN111555578A

CN111555578A - Full-phase double-drive brushless DC motor

Info

Publication number: CN111555578A
Application number: CN202010465245.7A
Authority: CN
Inventors: 吕建伟
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-28
Filing date: 2020-05-28
Publication date: 2020-08-18

Abstract

A full-phase dual-drive brushless direct current motor is characterized in that an inner stator excitation coil and an outer stator excitation coil are arranged on the inner side of a circular shell, two adjacent coils in each group are alternately connected in a positive direction and a reverse direction to form two phases, and opposite N and S magnetic field polarities are generated when the motor is electrified; the rotor magnet is arranged between the inner and outer groups of magnet exciting coils, and one surface of the rotor magnet, which is contacted with the outer coil, is also alternately arranged according to the N poles and the S poles; the control circuit composed of Hall one-way elements controls the current of the inner and outer two-phase magnet exciting coils, when the rotor magnet rotates by one magnet position, the positive and negative of the current direction are exchanged, so that the inner and outer two groups of magnet exciting coil magnetic poles are alternately switched on, and the magnetic poles generated by the magnet exciting coils are always repelled by the rotor magnet in the front direction and attracted by the rotor magnet in the rear direction through the alternate and continuous switching, so that the rotor is driven to rotate continuously.

Description

Full-phase double-drive brushless DC motor

Technical Field

The invention relates to the field of brushless direct current motors, in particular to a high-power brushless direct current motor for an electric automobile.

Background

The use of direct current motors in various fields is more and more extensive today with continuously improved intelligent automation degree, for example, direct current motors are widely used in automation control, intelligent robots, unmanned planes, new energy vehicles and the like, brushless direct current motors are also widely used due to the advantages of large starting torque, silence and no need of maintenance, and especially, the new energy vehicles have the requirements on the motors that the power is large and the volume is as small as possible and the motors are suitable for frequent starting and stopping, so the brushless direct current motors are widely used on the new energy vehicles; the performance of the existing brushless direct current motor can not be further improved, the excitation coils of the well-known brushless direct current motor controlled by the Hall position sensor mostly adopt a three-phase connection mode, and in order to prevent the number of dead point coils at the starting position and the number of magnets of a rotor from being asymmetrically staggered, the magnetic induction characteristics of a Hall element are utilized to control the alternate on-off of the excitation coils of two phases in the three phases to attract the magnets of the rotor to move forwards so as to drive the rotor to rotate and output torque force; according to the rotation principle of the magnetic field generator, only two thirds of the magnet exciting coils are involved in working when the magnetic field generator rotates, and the other one third of the magnet exciting coils are not all the magnet exciting coils involved in working when the magnet exciting coils wait for the exchange state, so that the energy efficiency of the magnetic field generator is only sixty-six percent; one assumption-we can not let every excitation coil participate in the work to apply force to the rotor magnet at the same time, we design the excitation coil corresponding to the same number of rotor magnets, connect the two adjacent excitation coils in the forward and reverse directions, generate the opposite magnetic pole to attract or push every magnet at the same time when the electricity is on, control the current reversal of the two excitation coils to make the magnetism reverse after the rotor rotates a magnet position, make the attraction change into the repulsion to push the magnet just rotating the front position of a little angle of the excitation coil, and generate the attraction to the magnet of the next opposite magnetic pole, so the magnetic pole direction of the excitation coil is exchanged repeatedly to make the rotor rotate continuously, also make every excitation coil participate in the work, its energy efficiency can not reach one hundred percent, but the design will appear zero angle when the magnet magnetic pole is rotated to align with the excitation coil magnetic pole, at this time, the control circuit also cuts off the current, and after the rotor rotates through the dead angle by inertia, the Hall element of the control circuit detects the opposite magnetic pole of the next magnet to control the current of the circuit to be opposite to the magnetic pole of the field coil, so that the rotor continuously rotates; the problem is that the motor can not be started just when the Hall element is at the dead angle position of conversion during starting, and the motor can continuously rotate only by being driven by external force; therefore, the existing brushless direct current motor controlled by the Hall position sensor overcomes the dead point by adopting the condition that the number of coil slots is not equal to the number of poles of a rotor magnet, and only two thirds of magnet exciting coils can work; it therefore appears that the idea of operating all the exciter coils simultaneously is difficult to achieve.

Disclosure of Invention

Aiming at the defect that the magnet exciting coils of the brushless direct current motor controlled by the Hall position sensor can not all participate in the work at the same time, the invention provides a full-phase dual-drive brushless direct current motor; the inner side of a circular shell is provided with an inner stator excitation coil and an outer stator excitation coil, every two adjacent excitation coils of the outer excitation coil are alternately connected in a positive direction and a negative direction to form two phases, the whole excitation coils generate opposite magnetic field polarities at intervals when being electrified, every two adjacent excitation coils of the inner excitation coil are also alternately connected in the positive direction and the negative direction to form two phases, the whole excitation coils generate opposite magnetic field polarities at intervals when being electrified, the number of the inner excitation coils and the number of the outer excitation coils are required to be correspondingly equal and even, the polarities of the two excitation coils on the corresponding surfaces of the inner excitation coil and the outer excitation coil are just opposite, namely the; the rotor is a concave magnet and is arranged at the edge and between the inner magnet exciting coil and the outer magnet exciting coil, the surface of the rotor magnet, which is contacted with the outer magnet exciting coil, is alternately arranged according to the N poles and the S poles, and the surface of the rotor magnet, which is contacted with the inner magnet exciting coil, is just reversed, so that the installation effect is that when the outer magnet exciting coil is electrified to generate an N pole magnetic field, the rotor magnet at the front position is repelled and the magnet at the rear position is attracted by the rotor magnet with the N poles, and the inner magnet exciting coil is electrified to generate an S pole magnetic field to be repelled and the magnet at the front position and the S pole at the inner side of the rotor magnet also attract the rotor magnet with the N poles, so that; when the traction angle of the rotor magnet rotating to the magnetic field aligned with the magnetic poles of the magnet exciting coil is zero, a Hall one-way position sensor arranged between the inner magnet exciting coil and the outer magnet exciting coil respectively controls to cut off the current of the inner magnet exciting coil and the outer magnet exciting coil and then switches the current direction to be switched on when detecting the interval between the two magnetic poles of the rotor and detecting the next different magnetic pole of the magnet, so that the adjacent two magnetic poles of the magnet exciting coil reversely repeat the previous working procedure, and the magnet rotor can continuously rotate; certainly, the inner and outer magnet exciting coils need to be installed in a staggered mode by a certain angle to ensure that the Hall position sensors of the inner and outer magnet exciting coils are not in dead point positions at the same time, and one of the inner and outer magnet exciting coils can drive the rotor to rotate through the dead point detection position of the Hall one-way position sensor of the other magnet exciting coil and then apply force to drive the rotor to rotate; each group of excitation coils of the control circuit needs four unidirectional Hall position elements which are respectively arranged at intervals among the four excitation coils, wherein two adjacent input ends are respectively connected with the anode and the cathode of a direct-current power supply, the output ends are connected in parallel and then connected with one end of the excitation coils, the other two adjacent input ends are also respectively connected with the anode and the cathode of the direct-current power supply, and the output ends are connected in parallel and then connected with the other end of the excitation coils to form a two-phase switch control circuit; the working principle of the magnetic field generator is that the characteristics of Hall one-way elements are utilized, when one Hall one-way element detects S in the rotation process of a rotor magnet, the adjacent two Hall one-way elements are conducted to load the positive pole of a circuit to one end of an excitation coil, the other Hall one-way element connected in parallel cannot be conducted to be in an off state when the other Hall one-way element detects N simultaneously, when the Hall one-way element connected with one end of the excitation coil detects S, the negative pole of a power supply is conducted to allow current to form a loop at the excitation coil to generate a magnetic field, and the other Hall one-way element connected in parallel cannot; when the rotor magnet rotates past a magnet position, the Hall one-way elements which are conducted in the four Hall one-way elements are switched off when detecting N, and are switched on when detecting S in the original off state, so that the currents of the two-phase magnet exciting coils are reversely switched on to generate opposite polar magnetism, and the rotor is driven to continuously rotate through alternate and continuous conversion; of course, each group of excitation coils can also use a Hall unidirectional element control logic circuit to control the reversal of the circuit. Therefore, the brushless direct current motor adopting the design of the inner exciting coil and the outer exciting coil can not only lead all the exciting coils to participate in work, but also form an inner and outer bidirectional driving which can be improved by one time compared with the direct current motor with the same volume, and each phase of the two exciting coils can be singly connected in parallel or connected in series and then connected in parallel, and the driving method is determined according to the voltage of the used current and the set power; in practical application, the current of a group of magnet exciting coils can be automatically cut off in the rotating process according to requirements so as to save electric energy; therefore, the full-phase dual-drive brushless direct current motor is a high-energy direct current motor which is most suitable for the requirements of electric automobiles.

The brushless direct current motor has the beneficial effect of greatly improving the energy efficiency of the brushless direct current motor.

Description of the drawings: FIG. 1 is a schematic diagram of the invention; FIG. 2 is a half sectional view.

In the figure: 1, a machine shell; 2 an outer field coil; 3, a rotor bracket; 4 a rotor magnet; 5 an inner exciting coil; 6, a rotating shaft; 7, a machine cover; 8 a housing bearing; 9 cover bearing.

The specific implementation mode is as follows: the outer magnet exciting coil 2 is fixed on the outer edge of a base in the machine shell 1, the inner magnet exciting coil 5 is fixed at the central position in the machine shell 1, the rotor magnet 4 is alternately arranged and fixed in a square frame of the rotor support 3 according to positive and negative magnetic poles, the rotating shaft 6 penetrates through the center of the rotor support 3 to be fixed with the rotor support and penetrates through a machine shell bearing 8 at the center of the machine shell 1 to enable the rotor magnet 4 on the rotor support 3 to be arranged between the inner magnet exciting coil and the outer magnet exciting coil, a machine cover bearing 9 on the machine cover 7 is sleeved and fixed on the rotating shaft 6, and the machine cover 7 and the edge of the machine shell 1 are fixed.

Claims

1. A full-phase dual-drive brushless DC motor is characterized in that: the inner and outer groups of magnet exciting coils controlled by the Hall position sensor all participate in the excitation work at the same time, and force is applied to the inner and outer groups of magnet exciting coils to push the rotor magnet between the two groups of magnet exciting coils to rotate.

2. The full-phase dual-drive brushless direct current motor according to claim 1 is characterized in that: two adjacent magnet exciting coils in each group are combined into two phases in a positive-negative connection mode, opposite magnetic field polarities are generated when the two phases are electrified, and when the rotor magnet rotates to a position and is controlled by a control circuit, the current directions of the two phases are changed to enable the magnetic poles of the magnet exciting coils to be simultaneously opposite.

3. The full-phase dual-drive brushless direct current motor according to claim 1 is characterized in that: the rotor is a concave magnet and is arranged at the edge and between the inner and outer groups of magnet exciting coils, and the surface of the rotor magnet, which is contacted with the outer magnet exciting coil, is alternately arranged according to the N poles and the S poles.