CN112825461A

CN112825461A - Star-connected phase-by-phase driven brushless motor and driver circuit

Info

Publication number: CN112825461A
Application number: CN201911144932.2A
Authority: CN
Inventors: 彭明; 彭宇科
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-18
Filing date: 2019-11-18
Publication date: 2021-05-21

Abstract

The invention provides a star-connected phase-by-phase driving brushless motor and a driver circuit, which are different from the traditional brushless motor in that at least two-phase windings need to be driven during star connection. The stator coils are connected in a star shape, the public end connected with each phase also serves as a driving end, the winding mode mainly adopts the winding mode that the coils of the same phase winding are wound between two adjacent tooth grooves of a single armature tooth, so that the rotor rotates to the position of the single armature tooth when being driven in each state, then the next state is driven, the rotor is driven to rotate in a mode of electrifying the coils of one phase state by state, and the driving efficiency of electric energy is improved. The invention adopts a mode of separating rotating speed regulation and pulse width modulation, adopts fixed pulse width with high duty ratio, and regulates the rotating speed by changing the rotating speed pulse frequency, thereby having large rotating speed range, keeping large torque and simultaneously improving the electric energy driving efficiency. The invention can also be used for motors wound across tooth slots.

Description

Star-connected phase-by-phase driven brushless motor and driver circuit

The invention discloses a star-connected phase-by-phase driving brushless motor and a driver circuit, comprising a brushless motor and a brushless motor driver circuit.

Technical Field

The invention relates to the technical field of brushless motors and brushless motor driver circuits.

Background art:

the brushless motor is composed of a motor main body and a driving circuit, and is a typical electromechanical integrated product.

The brushless motor is widely adopted in the new energy electric automobile, the efficiency of the brushless motor directly influences the cruising mileage of the electric automobile after single charging, and how to improve the efficiency of the brushless motor becomes a very key factor. The efficient energy conversion can be brought by the efficient electric energy driving, so that the longer endurance mileage and the energy saving are brought. In the conventional brushless motor, the star connection and the delta connection of the three-phase ac motor are almost extended. Which flows through at least two phase coils each time it is energized, one phase coil must be at a non-optimal efficiency when the other phase coil is driven at the best efficiency due to the different physical locations where the phase coils are mounted.

As can be seen from the above, in order to improve the cruising mileage of the new energy electric vehicle, the windings of the brushless motor must be precisely driven, and the driving efficiency can be improved to realize the optimal power output only by driving one group of windings at the best position each time, so that the cruising mileage of the new energy electric vehicle is improved; correspondingly, the electric unmanned aerial vehicle has the same requirement.

Disclosure of Invention

The invention provides a star connection phase-by-phase drive brushless motor and a driver circuit, in the brushless motor, a position sensor is positioned in front of a drive coil in an attraction drive mode, and the position sensor sends out a signal and then a driver energizes a phase coil behind the position sensor to generate a magnetic pole different from a rotor magnetic pole under the position sensor so as to attract a rotor to rotate to the position of the phase coil and then to the position of the next phase coil, thereby driving the rotor to rotate; in the repelling driving mode, the position sensor is positioned behind the driving coil, and after the position sensor gives a signal, the driver energizes the coil in front of the position sensor to generate a magnetic pole which is the same as the magnetic pole of the rotor below the position sensor so as to repel the rotor to rotate away from the position of the coil, so that the rotor is driven to rotate, and the rotor rotates to the position of the coil in the next phase in the same way. Only one phase of the coil is driven at each drive to obtain the best efficiency for driving the rotor. Because the rotor only rotates one tooth slot position by each driving, the torque pulsation is small. Because the rotor uses the multiple magnetic pole pairs, the driving circuit simultaneously generates acting force on all south poles and north poles, so that the rotor has the characteristic of large-range rotating speed and large-range torque, and different position sensors are switched during forward and reverse rotation, so that the forward and reverse rotation have the same performance.

In the brushless motor, because the winding directions of two adjacent coils of the same phase winding on the stator are opposite, when a driving current flows through the phase winding, armature teeth of the two adjacent coils of the phase winding respectively generate a south pole and a north pole, and the south pole and the north pole of the rotor are both driven simultaneously. The PWM pulse width modulation can be adjusted to enable the PWM pulse width modulation to be in a high duty ratio state all the time, the adjustment of the rotating speed is provided by the frequency of other driving pulses instead of the ordinary PWM pulse width modulation speed regulation, and the PWM pulse width modulation pulses keep higher duty ratios at all speeds, so that the high-efficiency and large-range rotating speed high-torque maintaining characteristic is achieved, and the pulse width can be reduced under the condition that the speed is kept basically unchanged and the torque can be reduced to further save electric energy.

The rotor of the brushless motor winding is a cylindrical magnetic material cylinder which is radially filled with permanent magnetism in an outer stator wound with coils when in an inner rotor structure, the cylinder can also be formed by embedding permanent magnets on a cylindrical magnetizer according to a manufacturing process, and the cylindrical magnetic material can be solid or hollow; when the outer rotor structure is a circular ring-shaped magnetic material ring which is radially filled with permanent magnetism and is wound by a coil, the outer rotor structure can also be formed by fixing permanent magnets on a circular ring-shaped object according to a manufacturing process.

The schematic diagrams of the stator coil winding and position sensor and the rotor structure are shown in the attached

drawings

1, 2, 3 and 4 (inner rotor structure) and 5 (outer rotor structure, winding method of the winding coil is the same as that of the inner rotor structure, the winding direction of the same phase winding between two adjacent tooth slots of a single armature tooth is opposite to that of two adjacent coils, and the winding direction is omitted here for clarity), and the attached

drawings

1, 2, 3 and 4 show the mode of winding the coil by a single armature tooth, but the mode of winding the coil across the armature teeth can also be used. There is no essential difference in principle.

The brushless motor rotor driving mode of the invention is to electrify the stator coils in sequence phase by phase, only one phase coil is electrified at each moment, the rotor is driven to rotate one tooth position, and the rotor is driven to rotate one tooth position when the next phase coil is electrified, so that the driving current directions of two adjacent driving states of the same phase winding are opposite, thereby forming the rotation of the rotor, and all south poles and north poles on the rotor are driven by each driving.

The drive circuit of the brushless motor consists of an adjustable pulse oscillator for controlling the rotating speed, a phase sequence generator, a PWM (pulse width modulation) pulse width modulator, a duty ratio adjuster, an AND gate for comparing a sensor signal with a phase sequence signal, a magnetic position sensor change-over switch consisting of electronic switches and a power driver (generally a high-power MOS (metal oxide semiconductor) transistor or an IGBT (insulated gate bipolar transistor) composite full-control type voltage drive type power semiconductor device module) for driving each phase winding coil.

Drawings

Fig. 1 is a schematic structural diagram of a brushless motor of the present invention (taking an inner rotor three-phase 8-pole, 24-slot as an example), wherein: (i) is a stator armature, (ii) is an inner rotor, (1) to 24 are armature teeth of the stator, (H1), H2, H3, H4, H5, and H6 are position sensors, (U + and U-are start ends of U-phase windings, respectively, (V + and V-are start ends of V-phase windings, respectively), and (W + and W-are start ends of W-phase windings, respectively.

Fig. 2, fig. 3 and fig. 4 are respective structural schematic diagrams of three-phase windings of the brushless motor of the present invention (taking three-phase 8-pole inner rotor and 24-slot as examples), wherein the three-phase windings are respectively an outer stator for winding coils, an inner rotor of a permanent magnet, and armature teeth 1 to 24. US1, US2, US3, US4 are south poles generated at the armature teeth when the U-phase coil is energized at a certain time, UN1, UN2, UN3, UN4 are north poles generated at the armature teeth when the U-phase coil is energized at that time; similarly, VS1, VS2, VS3, VS4 are south poles produced at the armature tooth when the V-phase coil is energized at a certain time, VN1, VN2, VN3, VN4 are north poles produced at the armature tooth when the V-phase coil is energized at that time; and WS1, WS2, WS3, WS4 are south poles generated at the armature teeth when the W-phase coil is energized at a certain time, WN1, WN2, WN3, WN4 are north poles generated at the armature teeth when the W-phase coil is energized at the certain time;

fig. 5 is a schematic structural diagram of the brushless motor of the present invention (taking three-phase 4-pole outer rotor and 12 slots as an example), and is a permanent magnet outer rotor, and is an inner stator armature for winding coils, N and S are 4 north and south poles of the permanent magnet outer rotor, US and UN are south and north poles generated by the armature teeth on the stator when the U-phase winding is energized at a certain time, VS and VN are south and north poles generated by the armature teeth on the stator when the V-phase winding is energized at another time, WS and WN are south and north poles generated by the armature teeth on the stator when the W-phase winding is energized at a different time, and H1, H2, H3, H4, H5, and H6 are position sensors.

Fig. 6 is a schematic diagram of a driving circuit (in the case of three-phase driving, the number of driving phases can be increased in this manner for an N-phase motor) SW1 of the present invention is a rotation/stop switch.

Fig. 7 is a schematic diagram of a power driver circuit according to the present invention (for example, three-phase driving, the number of driving phases can be increased for an N-phase motor).

Fig. 8 is a schematic diagram of a steering switching circuit of the present invention, and SW2 is a forward/reverse switch for effecting a steering change by switching different magnetic position sensors.

Detailed Description

The invention provides a star-connected phase-by-phase driving brushless motor and a driving circuit thereof, wherein a position sensor is positioned in front of a driving coil in the brushless motor in an attraction rotation mode according to the principles of opposite magnetic attraction and same magnetic repulsion, and a driver is used for electrifying a phase coil behind the position sensor after the position sensor gives a signal to generate magnetic force to attract a rotor to rotate to the position of the phase coil, so that the rotor is driven to rotate to the position of the next phase coil. In the repulsion force rotation mode, the position sensor is positioned behind the driving coil in the brushless motor, after the position sensor gives out a signal, the driver energizes the phase coil behind the position sensor to generate magnetic force to push the repulsion rotor to rotate away from the phase coil, and then the repulsion rotor rotates to the next phase coil position, so that the rotor is driven to rotate. The rotor is driven with best efficiency by driving only one phase coil in each driving, and the rotor has the characteristics of small torque pulsation, large rotating speed and large torque in a large range, and the magnetic sensors in different physical positions can be switched by adding an electronic switch in the forward and reverse rotation, so that the forward and reverse rotation have the same performance.

The number of the slots of the brushless motor stator is equal to the number of south and north magnetic poles of the permanent magnet rotor multiplied by the number of phases. Taking three-phase winding, four pairs of 8 poles are taken as an example, the number of the slots is equal to 3 multiplied by 8 poles, and the number of the slots is 24; if six pairs of 12 poles are used, 36 slots are used.

The main winding mode of the stator coil of the brushless motor winding of the invention is to wind between two adjacent tooth slots of a single armature tooth, and the winding directions of two adjacent coils of the same phase winding are opposite, namely, the two side slots of the single armature tooth are wound with partial coils of the same phase winding, taking a three-phase winding as an example, namely, a phase winding (U phase) is wound around the armature tooth 1 in one slot (slot 1) and one adjacent slot (slot 2), after the required number of turns is reached, a next phase winding (V phase) is wound around the armature tooth 2 in the adjacent slot (slot 2) and the next adjacent slot (slot 3), after the required number of turns is reached, the next phase winding (W phase) is wound around the armature tooth 3, after the required number of turns is reached, the next phase winding (W phase) is wound around the armature tooth 4, the armature tooth 5 and the armature tooth 6 in opposite directions, and the winding directions of two adjacent coils of the same phase winding are kept opposite until the winding is finished, and the same winding mode is adopted for more N-phase motors. When the winding mode of crossing armature teeth is adopted, the winding mode is the same except that a coil crosses certain armature teeth. One end of each phase winding of the motor stator is respectively connected to a respective power driving device on a brushless motor driver outside the motor, and the other end of each phase winding is completely connected inside the motor and led out of the motor to be connected to a common power driving device on the brushless motor driver.

And 2, FIGS. 3 and 4 are winding diagrams of three groups of windings of a U phase, a V phase and a W phase respectively. S and N are north and south magnetic poles of the rotor. H1, H2, H3, H4, H5, H6 are schematic position diagrams of 6 position sensors, two for each phase winding.

The power driving devices and the public power driving device for driving the winding to be electrified are composed of IGBT composite full-control voltage driving type power semiconductor devices, and high-power MOS tubes and other high-power devices can also be adopted.

The operation principle of the phase coil winding is described below by taking a repulsive force rotation mode (the position sensor is located behind the phase coil winding in the rotation direction) as an example, and the position sensor is located in front of the phase coil winding in the rotation direction when the attraction drive mode is adopted.

When the SW1 rotation/stop switch is in the off (rotation) state, one of the input terminals of each of U1 to U6 to which SW1 is connected is in the high state.

In the driving circuit of the brushless motor of the present invention as shown in fig. 6, the pulse oscillator IC1 with adjustable control speed generates oscillation pulses and outputs them to the three-phase six-state phase sequence generator formed by the IC2 decimal counter/pulse distributor CD4017, and generates the high level pulses of the three-phase six-state phase sequence of D0, D1, D2, D3, D4 and D5, and the position sensors (which can also adopt other types of position sensors for sensing magnetic signals) formed by the hall elements H1, H2, H3, H4, H5 and H6 respectively generate the signals of H1, H2, H3, H4, H5 and H6 and respectively input them to the and gates U1 to U6 after passing through the inverter, and the position sensors output the low level signals when the south pole of the rotor is near the south pole, and output the high level signals after the phase signals after the inversion by the inverter and the three-phase sequence generator formed by the IC2 decimal counter/pulse distributor CD4017 to output the three-phase sequence generator 0, d1, D2, D3, D4 and D5 are high-level pulse phase-inversed.

Driving state 1: when one south pole of the permanent magnet rotor is in a Hall element H1, H1 gives a low level which is inverted and then gives a high level to one input end of U1, when IC2 gives a high level signal D0, U1 outputs a high level, the high level output by U1 is divided into two paths, one path is connected to a triode Q1 to make it conductive, so that a photocoupler IC5 is conducted through SH1 to drive the IGBT of T1 to be conductive, the other path is given by U1 and the output signal of U7 and U2, the output signal of U3 is phase-changed or after the phase of the variable duty ratio signal phase output by U9 and IC1 and a PWM drive signal SL4 is output to drive the T8 to be conductive, a power supply + V flows through U + winding through T + 9 to U-winding and then through T8 to ground, the drive is completed, the current direction is T1 to T winding 8, the armature teeth of U on FIG. 2 make the IGBT rotate towards the US 862, armature teeth 4 generate north poles UN1 to drive rotation of north poles on the rotor towards armature teeth 5. similarly, armature teeth 7 generate south poles US2 to drive rotation of south poles on the rotor towards armature teeth 8, armature teeth 10 generate north poles UN2 to drive rotation of north poles on the rotor towards armature teeth 11, armature teeth 13 generate south poles US3 to drive rotation of south poles on the rotor towards armature teeth 14, armature teeth 16 generate north poles UN3 to drive rotation of north poles on the rotor towards armature teeth 17, armature teeth 19 generate south poles US4 to drive rotation of south poles on the rotor towards armature teeth 20, armature teeth 22 generate north poles UN4 to drive rotation of north poles on the rotor towards armature teeth 23, and one pulse rotation is completed.

Driving state 2: after the last pulse driving, when the south pole of the rotor rotates to the vicinity of the armature tooth 2 and is close to the Hall element H2, H2 gives a low level, the low level is inverted and then gives a high level to one input end of U2, when IC2 gives a high level signal of D1, U2 outputs a high level, the high level output by U2 is divided into two paths, one path is connected to a triode Q2 to conduct the triode, thereby a photocoupler IC7 is conducted to drive the IGBT of T3 to conduct through SH2, the other path of the high level signal given by U2 is connected between U7 and U1, the output signal of U3 is phase-changed or is connected between the PWM signal phase with variable duty ratio output by U9 and IC1 to output a PWM driving signal SL4 to drive the IGBT of T8 to conduct, a power supply + V flows through a V + winding to a V-winding through a T3, then passes through a winding of T8 to ground, the current direction of the rotor winding is T3 to T8, and the armature tooth on the graph 3 generates a winding to drive the south pole VS3 to drive the armature tooth 1, armature teeth 5 produce north poles VN1 to drive the north poles on the rotor to rotate towards armature teeth 6. similarly, armature teeth 8 produce south poles VS2 to drive the south poles on the rotor to rotate towards armature teeth 9, armature teeth 11 produce north poles VN2 to drive the north poles on the rotor to rotate towards armature teeth 12, armature teeth 14 produce south poles VS3 to drive the south poles on the rotor to rotate towards armature teeth 15, armature teeth 17 produce north poles VN3 to drive the north poles on the rotor to rotate towards armature teeth 18, armature teeth 20 produce south poles VS4 to drive the south poles on the rotor to rotate towards armature teeth 21, armature teeth 23 produce north poles VN4 to drive the north poles on the rotor to rotate towards armature teeth 24, completing the second pulse rotation.

Driving state 3: after the second pulse driving, when the south pole of the rotor rotates to the vicinity of the armature tooth 3 and is close to a Hall element H3, H3 gives a low level, the low level is inverted, the high level is given to an input end of U3, when IC2 gives a signal with D2 being a high level, U3 outputs a high level, the high level output by U3 is divided into two paths, one path is connected to a triode Q3 to be conducted, so that a photocoupler IC9 is conducted through SH3 to drive the IGBT of T5 to be conducted, the other path of high level signal given by U3 is connected with U7 and U1, the output signal of U2 is subjected to phase inversion or is connected with a PWM signal phase with variable duty ratio output by U9 and IC1 to output a PWM driving signal SL4 to drive the IGBT of T8 to be conducted, a power supply + V flows through W + winding to W695-through T5 to ground, and then passes through T2 to finish the first driving, the current direction is T5 to T53, the armature tooth winding, W winding of the rotor rotates to make the armature tooth generate WS 843, and the south pole 864 rotates to generate the, armature tooth 6 produces north pole WN1 and drives the rotation of north pole on the rotor to armature tooth 7, and similarly, armature tooth 9 produces south pole WS2 and drives south pole on the rotor to armature tooth 10, armature tooth 12 produces north pole WN2 and drives north pole on the rotor to armature tooth 13, armature tooth 15 produces south pole WS3 and drives south pole on the rotor to armature tooth 16, armature tooth 18 produces north pole WN3 and drives north pole on the rotor to armature tooth 19, armature tooth 21 produces south pole WS4 and drives south pole on the rotor to armature tooth 22, armature tooth 24 produces north pole WN4 and drives north pole on the rotor to armature tooth 1, accomplishes the third pulse rotation.

The next three pulse rotations will perform the current commutation process.

Driving state 4: when one south pole of the permanent magnet rotor reaches a Hall element H4 by the three-time pulse, H4 gives a low level which is inverted and then gives a high level to an input end of U4, when IC2 gives a high level signal of D3, U4 outputs a high level, the high level output by U4 is divided into two paths, one path is connected to U8 and U5, the output signal phase of U6 or a triode Q4 to conduct the high level signal, so that a photoelectric coupler is conducted by SH4 to drive the IGBT of T7 to conduct, the other path of high level signal given by U4 is connected with the PWM signal phase of variable duty ratio output by U10 and IC1 and then outputs a PWM drive signal SL1 to an IC6 field effect transistor driver to drive the IGBT of T2 to conduct, a power supply + V flows through the U-winding by T7 to U + and then passes through T2 to ground, the rotor is driven once, the current direction is T7 to T2, the winding of the U teeth makes the armature teeth generate three-time pulse to drive the south pole rotation to the front of the armature to rotate towards the front of the rotor. The armature teeth 7 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 8, similarly, the armature teeth 10 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 11, the armature teeth 13 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 14, the armature teeth 16 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 17, the armature teeth 19 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 20, the armature teeth 22 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 23, and the armature teeth 1 generate a north pole to drive the north pole on the north pole rotor to rotate towards the armature teeth 2, so that the fourth pulse rotation.

Driving state 5: after the fourth pulse driving, the south pole of the rotor rotates to the armature tooth 5 to be close to a Hall element H5, so that a low level is given by H5, a high level is given to an input end of U5 after phase inversion, when an IC2 gives a high level signal of D4, U5 outputs a high level, the high level output by U5 is divided into two paths, one path is connected to U8 and U5, the output signal phase of U6 or the other path is connected to a triode Q4 to make the triode conductive, so that the photoelectric coupler is conducted through SH4 to drive the IGBT of T7 to be conducted, the other path of high level signal given by U5 is conducted to drive the IGBT of T4 to be conducted through the phase of variable duty ratio signal phase output by U11 and IC1 and then outputs a PWM driving signal SL2 to an IC8 tube driver to drive the T4, a power supply + V flows through a V-winding to a V + through a T4 to the ground through T7 to complete the primary driving, the current direction is T7 to the T9, the armature tooth winding way to drive the armature tooth to generate the armature tooth to, the armature teeth 8 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 9, similarly, the armature teeth 11 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 12, the armature teeth 14 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 15, the armature teeth 17 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 18, the armature teeth 20 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 21, the armature teeth 23 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 24, and the armature teeth 2 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 3, so that the fifth pulse rotation is completed.

Driving state 6: after the fifth pulse driving, the south pole of the rotor rotates to the armature tooth 6 to be close to a Hall element H6, so that a low level is given by H6, a high level is given to an input end of U6 after phase inversion, when an IC2 gives a high level signal of D5, U6 outputs a high level, the high level output by U6 is divided into two paths, one path is connected to U8 and U4, the output signal phase of U5 or the other path is connected to a triode Q4 to make the triode conductive, so that the photoelectric coupler is conducted through SH4 to drive the IGBT of T7 to be conducted, the other path of high level signal given by U6 passes through a PWM 3 to an IC10 driver after the phase of the variable duty ratio signal phase output by U12 and IC1 to drive the IGBT of T6 to be conducted, a power supply + V flows through a W-winding to a W + through a PWM 7, then passes through T6 to the ground, one-time driving is completed, the current direction is T7 to T9, the armature tooth winding of the W6866 rotates to the south pole of the armature tooth to drive the south pole to drive the armature tooth, the armature teeth 9 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 10, similarly, the armature teeth 12 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 13, the armature teeth 15 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 16, the armature teeth 18 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 19, the armature teeth 21 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 22, the armature teeth 24 generate a south pole to drive the south pole on the rotor to rotate towards the armature teeth 1, and the armature teeth 3 generate a north pole to drive the north pole on the rotor to rotate towards the armature teeth 4, so that the sixth pulse rotation is completed.

And repeating the process from the pulse one-time driving state rotation to the sixth driving state pulse rotation to form continuous operation of the motor rotor, wherein each pulse rotation is that armature teeth on the stator coil simultaneously drive all south poles and north poles on the rotor.

When the stall switch SW1 is turned on, one input terminals of the and gates U1 to U6 and the and gates U9 to U12 are low, so that they are both output low, and the MOS/IGBT drivers of T1 to T8 are all in an off state, and the motor stalls.

In FIG. 6, IC4 generates power supply + VH about 15V higher than power supply + V from MC1555 and peripheral elements for supplying to photocoupler.

V1 in fig. 6 is a frequency regulator of rotation pulses related to phase-sequential drive pulses, by which the rotation speed of the motor is regulated, V2 for regulating the frequency of the pulse width modulation signal, and V3 for regulating the duty ratio of the pulse width modulation signal.

Fig. 8 is a magnetic position sensor switching circuit, H1 ', H2', H3 ', H4', H5 'and H6' are signals given by magnetic position sensors H1, H2, H3, H4, H5 and H6, respectively, the motor is driven to a high level at the first legs of IC13 and IC14 when the steering switch SW2 is in an off state, and output states are from B to Y, realizing signal transmission of H1 'to H1, H2' to H2, H3 'to H3, H4' to H4, H5 'to H5, H6' to H6, and the motor is driven to rotate in one direction; when the steering switch SW2 is in the on state, the first legs of IC13 and IC14 are low level, the output state is from a to Y, signal transmission of H4 'to H1, H5' to H2, H6 'to H3, H1' to H4., H2 'to H5, H3' to H6 is achieved, and the motor is rotated to the other direction. If only unidirectional rotation is required, H1 'and H1, H2' and H2, H3 'and H3, H4' and H4, H5 'and H5, and H6' and H6 are directly connected without using the circuit shown in FIG. 8.

In the driving circuit of the invention, the pulse width modulation can be in a high duty ratio state all the time, the regulation of the rotating speed is provided by the frequency of the rotating pulse, but the normal PWM pulse width speed regulation is not, the PWM pulse keeps a higher duty ratio at each speed, so that the driving circuit has the characteristics of high efficiency and large rotating speed range and high torque. Meanwhile, because the signals given by the position sensor and the rotation phase sequence signals are in phase relation, the rotor gradually achieves synchronization with the set rotating speed in the rotation process.

Because the rotating speed and the pulse width modulation duty ratio are generated respectively, after the set rotating speed is reached, the automatic control can be carried out by combining an artificial mode and the rotating speed after detection, and the pulse width modulation duty ratio can be adjusted to be reduced under the conditions of not influencing or reducing the rotating speed when the load is fixed and reduced (such as the new energy electric vehicle runs at a constant speed on a flat ground), so that the further energy saving is realized.

Because the winding mode of the stator of the brushless motor winding is the phase-to-phase power connection, compared with the traditional direct current brushless motor, the brushless motor winding has the characteristics of small rotation pulsation and large torque (the more the magnetic pole pairs and the more the slots are, the more the acting force points are, and the larger the torque force is) at each transposition, and the windings of all phases are driven when the rotor is in the best state, has the characteristic of high driving efficiency, meets the requirements of low rotation speed and high torque of the motor of the new energy electric vehicle, and is particularly suitable for new energy electric vehicles, electric unmanned aerial vehicles and the like due to high efficiency and energy conservation.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. Star connection is by looks drive brushless motor and driver circuit, including motor and drive circuit, its characterized in that: the brushless motor stator coil adopts star connection, the common end connected with each phase also serves as a driving end, a driving circuit of the brushless motor supplies power to a phase winding to drive when in each state, so that the rotor rotates to a single armature tooth position each time, a mode of separating rotation speed regulation and pulse width modulation is adopted, fixed pulse width with high duty ratio is adopted, and the rotation speed is regulated by a mode of changing the rotation speed pulse frequency.

2. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: two adjacent coils of the same phase winding of the stator of the brushless motor are opposite in winding direction, the windings of all phases are connected in a star shape, one end of each winding is connected in the motor and led out of the motor to be used as a common driving end, the other end of each winding of all phases is led out of the motor, and the number of phases is more than or equal to 2.

3. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: the relationship between the number of magnetic poles of the permanent magnet rotor of the brushless motor and the number of phases and the number of slots of the stator armature is as follows: the number of the stator armature slots is equal to the number of the magnetic poles in south and north of the permanent magnet rotor multiplied by the number of phases, and the number of the phases is more than or equal to 2.

4. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: a brushless motor stator uses two magnetic position sensors per phase winding.

5. The star-connected phase-by-phase drive brushless motor and driver circuit of claim 1 and claim 2, wherein: in each drive state a drive current flows through a phase winding of the brushless motor stator.

6. The star-connected phase-by-phase drive brushless motor and driver circuit of claim 1 and claim 2, wherein: the power driver for each phase winding is composed of two sets of drivers composed of compound fully-controlled voltage-driven power semiconductor devices connected in series, the leading-out end of each phase winding of the brushless motor is connected to the midpoint of the power driver for each phase winding, the common driving end of the brushless motor is also connected to the midpoint of a common power driver composed of a driver composed of two sets of compound fully-controlled voltage-driven power semiconductor devices connected in series, the upper and lower control ends of each power driver are controlled by different signals, and the power driver can also adopt a high-power MOS field effect transistor.

7. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: the upper arm of the power driving device for driving each phase after the phase taking of the first magnetic position sensor signal of each phase and the first phase sequence driving pulse signal of the same phase in the driver circuit; the second magnetic position sensor signal of each phase and the second phase sequence driving pulse signal of the same phase are subjected to phase inversion and then are subjected to phase inversion completely or are subjected to phase inversion to drive the upper arm of the common power driver, and the characteristic can also be realized by a micro control unit and an internal program.

8. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: in the driver circuit, the second magnetic position sensor signal of each phase and the second phase sequence driving pulse signal of the same phase are subjected to phase-inversion and then subjected to phase-inversion with a pulse width modulation signal or a direct current high level signal with the frequency of 100 Hz to 100 kHz to drive the lower arm of each phase power driving device; the first magnetic position sensor signal of each phase in the driver circuit is in phase with the first phase sequence driving pulse signal phase of the same phase and then is subjected to phase or, and is subjected to phase and then is subjected to phase and phase with a pulse width modulation signal or direct current high level re-phase with the frequency of 100 Hz to 100 kHz to drive the lower arm of the common power driving device.

9. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: the driver circuit adjusts the rotational speed of the motor by varying the frequency of the rotational pulses associated with the phase sequence drive pulses, and the pulse width modulation signal is used to assist in adjusting the rotational speed.

10. The wye-connected phase-by-phase drive brushless motor and driver circuit of claim 1, wherein: the brushless motor is realized by switching the magnetic position sensor in the rotating direction, and the characteristic can also realize the function of switching the magnetic position by using a micro control unit and an internal program.