CN111546905A

CN111546905A - Differential lock control module and control method thereof

Info

Publication number: CN111546905A
Application number: CN202010419160.5A
Authority: CN
Inventors: 杨明
Original assignee: Foshan Zhongjin Micro Electric Technology Co ltd
Current assignee: Foshan Zhongjin Micro Electric Technology Co ltd
Priority date: 2020-04-23
Filing date: 2020-05-21
Publication date: 2020-08-18
Also published as: CN111509937A; CN111884563A; CN111509936B; CN111509936A; CN112072819A; WO2021213499A1; CN111546884A

Abstract

A control method of a differential lock control module is used in cooperation with a differential lock control module of a differential lock motor system; includes step S1: acquiring three voltage phase signals P1, P2 and P3 corresponding to two ends of a differential switch through a phase sensing circuit; step S2: transmitting the three phase signals P1, P2, P3 to the electronic control unit ECM; step S3: the ECM calculates and determines the zero crossing time of three voltage phase signals P1, P2 and P3 and the electric angle range between the front and the back of the zero crossing time of the three voltage phase signals [ -15 degrees to +15 degrees ]; step S4: when the differential lock state is required to be entered from the differential state, the ECM outputs that the conduction time of the differential switch falls within the electric angle range, so that the two three-phase alternating-current motors are smoothly converted into the differential lock state; when the differential lock state is required to enter the differential state, the ECM outputs that the cut-off time of the differential switch falls within the electric angle range, so that the two three-phase alternating-current motors are smoothly converted into the differential state.

Description

Differential lock control module and control method thereof

Technical Field

The invention belongs to the technical field of new energy automobile control, and particularly relates to a differential lock control module and a control method thereof.

Background

Common new energy automobiles adopt a mechanical differential mechanism to realize the compatibility of the difference of the rotating speeds between driving wheels, but the traditional differential mechanism has the problems of heavy weight, mechanical loss, high cost, maintenance requirement and the like. Particularly, when the adhesion of the wheel on one side is insufficient, the wheel on the other side loses driving force, for example, the wheel on one side is suspended or falls into a muddy hole, so that the vehicle is possibly anchored, hidden dangers are brought to driving safety, and the situation is often seen in daily life. Aiming at the problem, differential locks are additionally arranged on partial load trucks and high-end off-road vehicles and passenger vehicles, so that the problem is solved, but the differential locks are complex in mechanical structure and high in cost, and the current vehicles with the differential locks are low in occupation ratio. The problems of the prior electric automobile and the hybrid automobile cannot be effectively solved.

Therefore, if a new technology is invented and applied to a new energy automobile, the differential function and the differential lock function are realized without installing an original mechanical differential, so that the weight is reduced, the cost is reduced, the maintenance is free, and the excellent technical effects in the aspects of driving stability, safety and controllability are brought.

In another invention patent application (prior application No. 202010326658.7 of priority) of the same inventor, a quasi-differential lock driving system based on "midline differential lock principle" is included, and the differential control module of the present application is applied to the quasi-differential lock control system, so the quasi-differential lock control system is in the background of the present application.

The technical characteristics of the system comprise a midline theorem, according to the first aspect of the invention, the invention provides a quasi-differential lock control system, which comprises first to nth three-phase alternating current motors, wherein n belongs to Z + and n is more than or equal to 2, and each alternating current motor comprises a three-phase winding.

Namely: u-phase windings of the 1 st to nth motors are respectively U1 to Un, V-phase windings of the 1 st to nth motors are respectively V1 to Vn, and W-phase windings of the 1 st to nth motors are respectively W1 to Wn; leading out a head end H and a tail end T from each phase winding, wherein the head ends of the U1-Un windings are Hu 1-Hun respectively, the tail ends of the U1-Un windings are Tu 1-Tun respectively, the head ends of the V1-Vn windings are Hv 1-Hvn respectively, the tail ends of the V1-Vn windings are Tv 1-Tvn respectively, the head ends of the W1-Wn windings are Hw 1-Hwn respectively, and the tail ends of the W36 1-Twn respectively.

Determining the phase sequence of the motor windings according to the rotation direction requirement of the output shaft of each motor, dividing the three-phase windings of all the motors into three groups of a U phase, a V phase and a W phase according to the phase sequence of the windings, namely a U phase group, a V phase group and a W phase group, wherein the windings in each group are sequentially connected end to end according to the sequence of the motors 1-n in which the windings are positioned and the winding phase sequence, and the specific series connection form is as follows.

N U-phase windings U1-Un of all the motors are connected in series end to end, m is more than or equal to 1 and less than or equal to n-1, m belongs to Z +, the tail end Tum of the U-phase winding Um of the m motor is connected with the head end Hw (m +1) of the U-phase winding U (m +1) of the m +1 motor, namely the tail end Tu1 of the winding U1 is connected with the head end Hu2 of the winding U2, the tail end Tu2 of the winding U2 is connected with the head end Hu3 of the winding U3, the connection is executed according to the connection rule until the tail end Tu (n-1) of the winding U (n-1) is connected with the head end Hun of the winding Un, the n U-phase windings of all the motors are sequentially connected in series end to form a U-phase one edge, the Hu1 of the winding U1 is the head end of the edge, and the Tu; dividing the edge into n equal parts by n-1 head-tail connection nodes on the edge, and enabling a connection node between the tail end Tum of a U-phase winding Um of an m-th motor and the head end Hu (m +1) of the U-phase winding U (m +1) of an m + 1-th motor to be Dum among the n-1 head-tail connection nodes, wherein the node Dum is an n equal division point of the edge; n V-phase windings V1-Vn of all the motors are connected in series end to end, m is more than or equal to 1 and less than or equal to n-1, m belongs to Z +, the tail end Tvm of the V-phase winding Vm of the mth motor is connected with the head end Hv (m +1) of the V-phase winding V (m +1) of the mth motor, namely the tail end Tv1 of the winding V1 is connected with the head end Hv2 of the winding V2, the tail end Tv2 of the winding V2 is connected with the head end Hv3 of the winding V3, the connection is executed according to the connection rule until the tail end Tv (n-1) of the winding V (n-1) is connected with the head end Hvn of the winding Vn, the n V-phase windings of all the motors are sequentially connected in series end to form a V-phase one side, the tail end of the head end Tv1 of the winding V-phase side of the V1, and the tail; n-1 head-to-tail connection nodes on the edge divide the edge into n equal parts, and in the n-1 head-to-tail connection nodes, the connection node between the tail end Tvm of the V-phase winding Vm of the m-th motor and the head end Hv (m +1) of the V-phase winding V (m +1) of the m + 1-th motor is Dvm, so that the node Dvm is an n equal part of the edge; n W-phase windings W1-Wn of all the motors are connected in series end to end, m is more than or equal to 1 and less than or equal to n-1, m belongs to Z +, the tail end Twm of the W-phase winding Wm of the mth motor is connected with the head end Hw (m +1) of the W-phase winding W (m +1) of the mth motor, namely the tail end Tw1 of the winding W1 is connected with the head end Hw2 of the winding W2, the tail end Tw2 of the winding W2 is connected with the head end Hw3 of the winding W3, the connection is executed according to the connection rule until the tail end Tw (n-1) of the winding W (n-1) is connected with the head end Hwn of the winding Wn, the n W-phase windings of all the motors are sequentially connected in series end to form a W-phase one side, the tail end of the head end Twn 1 of the winding W1 is the head end of the side; the n-1 end-to-end connection nodes on the side divide the side into n equal parts, and in the n-1 end-to-end connection nodes, the connection node between the tail end Twm of the W-phase winding Wm of the mth motor and the head end Hw (m +1) of the W-phase winding W (m +1) of the mth +1 motor is Dwm, so that the node Dwm is an n equal part of the side.

And connecting the U-phase side, the V-phase side and the W-phase side end to end according to the triangular connection mode of the alternating current motor to form a new large triangular connection method, namely: connecting a head end Hu1 of a U-phase winding U1 of a 1 st motor with a tail end Twn of a W-phase winding Wn of an nth motor, and setting a connecting node as A; connecting the head end Hv1 of the V-phase winding V1 of the 1 st motor with the tail end Tun of the U-phase winding Un of the nth motor, and setting a connection node as B; connecting the head end Hw1 of the W-phase winding W1 of the 1 st motor with the tail end Tvn of the V-phase winding Vn of the nth motor, and setting a connecting node as C; the nodes A, B, C are the three vertices of the large triangle and are used for connecting a three-phase alternating current power supply.

The control circuit of the quasi-differential lock comprises three independent control switches Ka, Kb and Kc, wherein the switches Ka, Kb and Kc are all switch devices comprising two control ends, and the two control ends are connected with alternating current when the switch devices are in a conducting state, and are disconnected with the alternating current when the switch devices are not in a conducting state.

And connecting one control end of the switch Ka with a vertex A of the large triangle, and connecting the other control end of the switch Ka with an n bisector Dvm on the opposite side of the vertex A, wherein when the switch Ka is conducted, the switch Ka forms an n bisector line on the opposite side of the vertex A in the large triangle.

And connecting one control end of the switch Kb with a vertex B of a large triangle, and connecting the other control end of the switch Kb with an n equal division point Dwm on the opposite side of the vertex B, wherein when the switch Kb is conducted, the switch Kb forms an n equal division middle line on the opposite side of the vertex B in the large triangle.

And connecting one control end of the switch Kc with a vertex C of a large triangle, and connecting the other control end of the switch Kc with an n bisector Dum on the opposite side of the vertex C, wherein when the switch Kc is switched on, the switch Kc forms an n bisector line of the opposite side of the vertex C in the large triangle.

When the switches Ka, Kb and Kc are all cut off, on the electrical connection relationship, each motor is still in a series connection relationship, n phase windings on each side are connected in series to share the phase voltage of the three-phase alternating current power supply, the phase currents of each motor are equal, when all the motors have the same electrical parameters and balanced loads, the corresponding phase windings of each motor equally share the power supply voltage of each phase in the three-phase alternating current power supply, namely each winding shares 1/n of the phase voltage of the three-phase power supply; when the motor load is unbalanced, the rotating speed of the motor with a heavy load is reduced, so that the inductance is reduced, the voltage shared by the motor is reduced, the power ratio is reduced, the rotating speed of the motor with a light load is increased, the inductance is increased, the voltage shared by the motor is increased, the power ratio is increased, the rotating speed is increased, and the differential function of automatic reverse load induction voltage distribution is realized among the motors.

When the switches Ka, Kb and Kc are all on, the connection of the three n-equi-parting neutral lines is equivalent to dividing the large triangle into two small triangles in electrical connection, according to the fact that, when the vertex A, B, C turns on the three-phase ac power supply,

wherein, one triangle is a first small triangle which is formed by three sides of a U-phase side formed by connecting U-phase windings U1-Um of the 1 st to the m-th motors in series, a V-phase side formed by connecting V-phase windings V1-Vm in series and a W-phase side formed by connecting W-phase windings W1-Wm in series and has a vertex of A, B, C, and the rotor turning directions of the 1 st to the m-th motors operating in the first small triangle are respectively consistent with the rotor turning directions of the 1 st to the m-th motors operating in a large triangle state when switches Ka, Kb and Kc are all cut off due to phase sequence relation; the other triangle is a second small triangle which is formed by three sides, namely a side where a U phase is formed by connecting U (m +1) -Un phase windings of (m +1) -nth motors in series, a side where a V phase is formed by connecting V phase windings V (m +1) -Vn in series and a side where a W phase is formed by connecting W phase windings W (m +1) -Wn in series, and the vertex is A, B, C, and the rotor turning directions of the 1 st-mth motors operating in the second small triangle are respectively consistent with the rotor turning directions of the 1 st-mth motors operating in a large triangle state when switches Ka, Kb and Kc are all cut off due to the phase sequence relation.

Namely: numbering n three-phase alternating current motors according to a sequence of 1-n, dividing phase attributes of windings of all the motors according to the rotating direction requirement of an output shaft of each numbered alternating current motor, namely, sequentially connecting the U-phase windings of all the motors into one group, the V-phase windings into one group and the W-phase windings into one group, sequentially connecting the U-phase windings, the V-phase windings and the W-phase windings in series according to the numbering sequence of the motor in which the windings are positioned in each group to form one edge, obtaining three edges belonging to the U-phase, the V-phase and the W-phase, forming n equal division points of the edge by the head-tail connection nodes of adjacent windings in each edge, determining the head-tail terminals of each edge according to the same winding arrangement sequence, connecting the three edges obtained by connecting the head-tail windings of different phases in series according to a triangular connection method of the alternating current motors to form a large triangular connection relation, and connecting each top point of the large triangle with a corresponding n equal division point, the three bisected central lines are connected and then cut into two parts, the two cut parts are equivalent to two new small triangles on an electrical connection system, the vertexes of the two small triangles are coincided with the three vertexes of the large triangle, the three coincided vertexes are connected with the three-phase alternating current power supply, each motor running in each small triangle still keeps the rotor turning of the motor when the large triangle runs, and the phase sequence connection relationship of obtaining the same turning direction by the three bisected central lines is called the central line theorem of the three-phase alternating current motor; and the two small triangles are in electrical parallel connection and respectively and independently bear three-phase alternating current power supplies, if the motor in the first small triangle is used for respectively driving m mutually independent driving wheels arranged in the first shaft, and simultaneously, the motor in the second small triangle is also used for respectively driving n-m mutually independent driving wheels arranged in the second shaft, an electric system between two shafts independently bears the three-phase alternating current power supplies, so that the torques between the first shaft and the second shaft are mutually independent, and the function equivalent to a differential lock is realized between the two shafts, namely, the inter-shaft differential lock of the first shaft and the second shaft is realized, compared with 1: 1, the power supply of the motor in the first shaft and the power supplies of all the motors in the second shaft are in parallel connection, and a certain rotational speed deviation occurs on different shafts due to load difference, so that the differential lock realized by the electrical connection relation is not completely equal to the complete locking of a mechanical differential lock, therefore, the differential lock in the electrical relation is called a quasi differential lock, the relation of the quasi differential lock is formed between the first shaft and the second shaft, and for a vehicle with the differential lock control system applied to wheel train driving, the quasi differential lock is superior to a rigid mechanical differential lock, so that the inter-shaft quasi differential lock is realized between the first shaft and the second shaft.

When m is 1 and n-m is more than 1, only 1 motor is arranged in the first small triangle at the moment, the motor independently bears a three-phase alternating current power supply, so that the differential function of automatic reverse load induction voltage distribution of the motor in the mth motor and the second small triangle is avoided, and a quasi differential lock function is realized between the mth motor on the first shaft and the second shaft; when m is larger than 1, a differential function of automatic reverse load sensing voltage distribution is realized among m motors in the first small triangle, a quasi differential lock function is not realized among m motors in the first shaft, and a quasi differential lock function is realized between the first shaft and the second shaft; when m is more than 1 and n-m is equal to 1, only 1 motor is arranged in the second small triangle, the motor independently bears a three-phase alternating current power supply, so that the nth motor and the motor in the first small triangle have no differential function of automatic reverse load sensing voltage distribution, and a quasi-differential lock function is realized between the nth motor on the second shaft and the first shaft; when m is not equal to 1 and n-m is larger than 1, a differential function of automatic reverse load sensing voltage distribution is formed among n-m electrodes in the second small triangle, and a quasi differential lock function is not formed among m motors in the second shaft.

Namely, when the three switches Ka, Kb and Kc are all switched on, the three n-branch center lines of the large triangle formed by the three switches form a center line differential lock between shafting, and the function of a quasi-differential lock is realized.

According to the working condition requirement, the three switches Ka, Kb and Kc are switched on or off in time, so that the functions of inter-axle differential and inter-axle quasi-differential lock are realized between different shafting where the motors respectively belonging to the two small triangles are positioned, and the functions of differential and the driving performance of the differential lock are realized;

when any one of the two small triangles contains h motors, the inside of the small triangle is connected again in the 3 h equal-dividing central line mode, the central line theorem is still met, and the motors inside the small triangle which are divided into smaller triangles again still keep the original steering; on the basis, when the middle lines inside the small triangles are connected or disconnected in time, the function of the quasi-differential lock inside the small triangles can be realized, and then the differential lock and the quasi-differential lock between the axles after the middle lines are connected for the first time and the differential lock and the quasi-differential lock between the gear trains inside the shafting after the middle lines are connected for the second time to the h time are realized, and the driving performance of the differential lock and the differential lock between the shafting and the gear trains on the vehicle are further optimized and controlled.

In a preferred embodiment of the system, a quasi-differential speed lock control system comprising a first motor and a second motor is further provided, and the system is a more direct technical scheme applied to a vehicle driving system, and the connection relation of alternating current motor windings is shown in the accompanying

drawings

1 and 2.

The three-phase winding of first motor is first winding, second winding and third winding, the head and the tail two terminals of first winding are 11 and 12 respectively, the head and the tail two terminals of second winding are 21 and 22 respectively, the head and the tail two terminals of third winding are 31 and 32 respectively, the three-phase winding that the second motor has is fourth winding, fifth winding and sixth winding, the head and the tail two terminals of fourth winding are 41 and 42 respectively, the head and the tail two terminals of fifth winding are 51 and 52 respectively, the head and the tail two terminals of sixth winding are 61 and 62 respectively, with all three-phase winding according to motor order and winding phase sequence in proper order head and tail series connection, promptly: the first winding terminal 12 is connected to the fourth winding terminal 41 at a connection node Z, the second winding terminal 22 is connected to the fifth winding terminal 51 at a connection node X, and the third winding terminal 32 is connected to the sixth winding terminal 61 at a connection node Y; and then, connecting the terminal 11 of the first winding with the terminal 62 of the sixth winding, and setting the connection node as a, the terminal 21 of the second winding with the terminal 42 of the fourth winding, and setting the connection node as B, and the terminal 31 of the third winding with the terminal 52 of the fifth winding, and setting the connection node as C.

The three windings of the first electrical machine and the three windings of the second electrical machine form a first series-connected large delta connection: the A, B, C is taken as a vertex, the first winding serial branch and the fourth winding serial branch are taken as one side, the second winding serial branch and the fifth winding serial branch are taken as one side, the third winding serial branch and the sixth winding serial branch are taken as one side, and the three sides form an equilateral triangle structure; or the three windings of the first motor and the three windings of the second motor form a second series connection type of large delta connection: that is, X, Y, Z is taken as a vertex, the fifth and third winding serial branches are taken as one side, the sixth and first winding serial branches are taken as one side, and the fourth and second winding serial branches are taken as one side, and the three sides form an equilateral triangle structure.

When the first series connection type delta connection is adopted, the bisection midpoint of the side where the first and fourth winding series branches are located is Z, the bisection midpoint of the side where the second and fifth winding series branches are located is X, and the bisection midpoint of the side where the third and sixth winding series branches are located is Y.

The quasi-differential speed lock control circuit comprises three control switches, namely a first switch K1, a second switch K2 and a third switch K3, wherein two control ends of the K1 are respectively connected with a vertex A of the equilateral triangle and a bisection midpoint X of opposite sides of the vertex A, so that the first switch K1 forms a bisection center line of the side, two control ends of the K2 are respectively connected with a vertex B and a bisection midpoint Y of opposite sides of the vertex B, so that the second switch K2 forms a bisection center line of the side, two control ends of the K3 are respectively connected with a fixed point C and a bisection midpoint Z of opposite sides of the vertex C, and the third switch K3 forms the bisection center line of the side.

And a three-phase alternating current power supply is applied to the top point A, B, C, and the on and off of the switches K1-K3 are controlled timely, so that the corresponding differential speed and quasi-differential speed lock functions are realized.

When the K1, the K2 and the K3 are in an off state, the windings of the first motor and the second motor are in a series connection relationship, namely the first winding and the fourth winding are connected in series to bear A-B interphase voltage, the second winding and the fifth winding are connected in series to bear B-C interphase voltage, the third winding and the sixth winding are connected in series to bear C-A interphase voltage, and the rotation direction of rotors of the two motors is ensured to meet the design requirement when the windings are connected, the two motors are both arranged in a forward rotation manner, the two motors share three-phase alternating current power voltage, the currents of the two motors are equal, when the electrical parameters of the two motors are the same and the loads are balanced, the voltage shared by the two motors is approximately half of the power voltage, when the loads of the two motors are unbalanced, the rotating speed of a load is reduced in inductance, the voltage shared is reduced, the power and the rotating speed are reduced, the rotating speed of the motor with, Therefore, the power and the rotating speed are increased, and the differential function of automatic reverse load induction voltage distribution is realized between the output shafts of the two motors, namely the voltage shared by the stator windings of different motors is in positive correlation with the inductance of the windings and in reverse correlation with the load of the motors.

When the switches K1, K2 and K3 are all switched on, namely, the A-X neutral line is switched on, the B-Y neutral line is switched on, the C-Z neutral line is switched on, the first, second and third windings of the first motor respectively bear A-C interphase voltage, B-A interphase voltage and C-B interphase voltage, the fourth, fifth and sixth windings of the second motor respectively bear C-B interphase voltage, A-C interphase voltage and B-A interphase voltage, the two motors form a parallel connection relation, the rotation direction of the two motors is consistent with the rotation direction of the two motors when the two motors are connected in series due to phase sequence phase difference, the two motors independently bear three-phase alternating current voltage and independent torque, and the function of a quasi-differential lock is realized, namely, the three switches K1, K2 and K3 are all communicated with three central lines of the equilateral triangle to form a central line differential lock, and the differential function of the reverse load sensing voltage distribution is lost between the two motors.

The three switches K1, K2 and K3 are switched on or off in due time according to the working condition requirement, so that a quasi differential lock control system consisting of the two motors and the quasi differential lock control circuit realizes the control functions of real-time differential and quasi differential lock, and has the driving performance of differential lock and differential lock;

when the triangle connection method of the second series connection mode is adopted, the vertex of the equilateral triangle is X, Y, Z, the bisected middle points of the three sides of the equilateral triangle are A, B, C respectively, and when the vertex X, Y, Z and the corresponding opposite side middle points are provided with the quasi differential lock control circuit, the two motors and the quasi differential lock control circuit which is formed jointly form a system like the first series connection method, the real-time differential and quasi differential lock control function is realized, and the driving performance of the differential lock and the differential lock are achieved.

The technical scheme of the application is matched with the technical scheme of a 'differential module' part in a core circuit in the differential driving system in the technical scheme.

Disclosure of Invention

The inventor invents a differential control module based on a neutral line differential locking principle of an alternating current motor and a control method thereof through creative labor, and the problem is solved easily.

The technical scheme of the invention is as follows:

according to a first aspect of the invention, a differential lock control module is provided, which is applied to a control circuit of a differential lock motor system, wherein the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, namely each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular manner according to the end to end connection mode, three vertexes of the connected triangle are used for connecting an external three-phase alternating current power supply, a switch is respectively connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total, namely the differential lock switch; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that:

the differential lock control module comprises the three switches, the three switches comprise three high-power transistors Q1, Q2, Q3, three full-wave rectifier bridges Z1, Z2, Z3, three photoelectric couplers N1, N2, N3 and three grid voltage control circuits G1, G2 and G3, wherein,

the grid voltage control circuits G1, G2 and G3 respectively have a grid voltage supply terminal, an output terminal, a signal input terminal and an emitter connecting terminal,

the photoelectric couplers N1, N2 and N3 are respectively provided with an input end and an output end,

the three full-wave rectifier bridges Z1, Z2 and Z3 respectively have two alternating current input ends and two rectification output ends, the two rectification output ends are a positive end and a negative end,

the output ends of the photoelectric couplers N1, N2 and N3 are respectively connected with the signal input ends of the grid voltage control circuits G1, G2 and G3,

emitter connection ends of the gate voltage control circuits G1, G2 and G3 are respectively connected with emitters of the three high-power transistors Q1, Q2 and Q3, output ends of the gate voltage control circuits G1, G2 and G3 are respectively connected with grids of the three high-power transistors Q1, Q2 and Q3, gate voltage supply ends of the gate voltage control circuits G1, G2 and G3 are used for being connected with three paths of mutually independent gate supply voltages provided by an external circuit, the gate supply voltages are used for respectively providing gate working voltages for the three high-power transistors Q1, Q2 and Q3 independently,

the emitters of the three high-power transistors Q1, Q2 and Q3 are also respectively connected with the negative terminals of the rectified outputs of the three full-wave rectifier bridges Z1, Z2 and Z3, the collectors of the three high-power transistors Q1, Q2 and Q3 are respectively connected with the positive terminals of the rectified outputs of the three full-wave rectifier bridges Z1, Z2 and Z3,

the three full-wave rectifier bridges Z1, Z2 and Z3 respectively have two alternating current input ends which are respectively used for connecting one vertex of the triangle and the middle connection point of the vertex opposite side;

when on-signals are input at the input ends of the photocouplers N1, N2 and N3, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively turned on through the photocouplers N1, N2 and N3 and the grid voltage control circuits G1, G2 and G3, so that the three switches are turned on to realize the differential lock function between the output shafts of the two three-phase alternating current motors; when the input ends of the photocouplers N1, N2 and N3 input cut-off signals, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively cut off through the photocouplers N1, N2 and N3 and the grid voltage control circuits G1, G2 and G3, so that the three switches are disconnected, and the differential function between the output shafts of the two three-phase alternating current motors is realized.

According to a second aspect of the present invention, there is provided a control method for a differential lock control module, which is applied to a control circuit of a differential lock motor system, and is used in cooperation with the differential lock control module according to the first aspect of the present invention; the differential lock motor system also comprises a phase sensing circuit and an electronic control unit ECM, wherein the phase sensing circuit senses the voltage phase of two alternating current input ends of each of the three full-wave rectifier bridges Z1, Z2 and Z3, the electronic control unit ECM has the functions of operation and signal processing, and is characterized by comprising the following steps of,

step S1: acquiring three voltage phase signals P1, P2 and P3 corresponding to the alternating current input ends of the full-wave rectifier bridges Z1, Z2 and Z3 respectively through the phase sensing circuit;

step S2: transmitting the three voltage phase signals P1, P2, P3 acquired to the electronic control unit ECM;

step S3: the electronic control unit ECM obtains the zero-crossing point times and the electrical angles before and after the zero-crossing point times of the three voltage phase signals P1, P2, P3 by calculation, wherein the electrical angle range before and after the zero-crossing point time includes the electrical angles before and after the zero-crossing point time [ -15 ° - +15 ° ];

step S4: when the ECM enters a differential lock state from a differential state according to working conditions, the electronic control unit ECM outputs three conducting signals which are respectively transmitted to input ends of three photoelectric couplers N1, N2 and N3, and the electric angle ranges of the starting moments of the three conducting signals before and after the zero-crossing moments of three voltage phase signals P1, P2 and P3 are [ -15 degrees to +15 degrees ], so that the output shafts of the two three-phase alternating current motors are converted into the differential lock state from the differential state; when the ECM calculates that the two three-phase alternating current motors need to be switched from the differential lock state to the differential state, the electronic control unit ECM outputs three cut-off signals which are respectively transmitted to the input ends of the three photoelectric couplers N1, N2 and N3, and the electric angle ranges of the starting moments of the three cut-off signals before and after the zero-crossing moments of the three voltage phase signals P1, P2 and P3 are between-15 degrees and +15 degrees, so that the two three-phase alternating current motors are switched from the differential lock state to the differential state.

Further, a control method of the differential lock control module is provided, which is characterized in that the time length of an on signal input at the input ends of the photocouplers N1, N2 and N3 is t1, the time length of an off signal input is t2, the signal period is t1+ t2, the frequency of the external alternating current power supply is f1, and when the differential lock switch is required to be switched on, the t1+ t2 is enabled to be more than or equal to 5/f 1.

Further, a control method of the differential lock control module is also provided, which is characterized by further comprising a differential lock soft loading method: the input end of the photoelectric couplers N1, N2 and N3 is provided with an input on-signal duration t1, an input off-signal duration t2 and a signal period t1+ t2, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively switched on or off by the photoelectric couplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, the conduction ratios gamma of the three switches are t1/(t1+ t2), and the function of controlling the differential rate between the output shafts of the two three-phase alternating current motors is realized by controlling the conduction ratios gamma; the differential lock soft loading method is characterized in that the conduction ratios gamma of the three switches are t1/(t1+ t2) and are gradually increased, so that the conduction duty ratios of the three switches are gradually increased, and the soft loading control function of the differential lock between the output shafts of the two three-phase alternating current motors is realized through gradual adjustment of the conduction ratios and the difference rate.

Further, a control method of the differential lock control module is also provided, which is characterized by further comprising a differential lock soft load shedding method: the input on-signal time duration of the input ends of the photocouplers N1, N2 and N3 is t1, the input off-signal time duration is t2, the signal period is t1+ t2, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively switched on or off through the photocouplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, the conduction ratios gamma of the three switches are t1/(t1+ t2), and the function of controlling the difference rate between the output shafts of the two three-phase alternating current motors is achieved through controlling the conduction ratios gamma; the differential lock soft load shedding method is characterized in that the conduction ratios gamma of the three switches are t1/(t1+ t2) and are gradually reduced, so that the conduction duty ratios of the three switches are gradually reduced, and the soft load shedding control function of the difference rate between the output shafts of the two three-phase alternating current motors is realized through gradual adjustment of the conduction ratios and the difference rate.

In practice, the duty cycle of the input control pulse is provided to effect a change in the conduction rate γ of the switch t1/(t1+ t2), with the difference rate being adjusted accordingly.

According to a third aspect of the invention, a differential lock control module is provided, which is applied to a control circuit of a differential lock motor system, wherein the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular manner according to the end to end connection mode, three vertexes of the connected triangle are used for connecting an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total, namely a differential lock switch; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that:

the differential lock control module comprises the three switches, the three switches comprise three relays RL1, RL2 and RL3, the relays RL1, RL2 and RL3 are electromagnetic relays provided with control coils and two normally-open contacts respectively, and the two normally-open contacts of the relays RL1, RL2 and RL3 are used for connecting one vertex of the triangle and the middle connection point of the vertex opposite side respectively;

when the control coils of the relays RL1, RL2 and RL3 input conducting signals, normally open contacts of the relays RL1, RL2 and RL3 are respectively connected with a vertex of the triangle and a middle connecting point of the opposite sides of the vertex, so that the function of a differential lock between output shafts of two three-phase alternating current motors is realized; when the control coils of the relays RL1, RL2 and RL3 input cut-off signals, the relays RL1, RL2 and RL3 respectively disconnect one vertex of the triangle from the middle connecting point of the vertex opposite sides, so that the differential function between the output shafts of the two three-phase alternating current motors is realized.

According to a fourth aspect of the invention, a differential lock control module is provided, which is applied to a control circuit of a differential lock motor system, wherein the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular manner according to the end to end connection mode, three vertexes of the connected triangle are used for connecting an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total, namely a differential lock switch; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that:

the differential lock control module comprises the three switches, the three switches comprise three relays RL1, RL2 and RL3, the relays RL1, RL2 and RL3 are contactless electronic relays with input ends and two control ends respectively, and the two control ends of the relays RL1, RL2 and RL3 are respectively used for connecting one vertex of the triangle and the middle connection point of the vertex opposite side;

when the input ends of the relays RL1, RL2 and RL3 input conducting signals, two control ends of the relays RL1, RL2 and RL3 are respectively connected with a vertex of the triangle and a middle connection point of the vertex opposite sides, so that the function of a differential lock between output shafts of two three-phase alternating current motors is realized; when the input ends of the relays RL1, RL2 and RL3 input cut-off signals, the relays RL1, RL2 and RL3 respectively disconnect one vertex of the triangle from the middle connecting point of the vertex opposite sides, and the differential function between the output shafts of the two three-phase alternating current motors is realized.

The invention has the beneficial effects that: the corresponding functions of the electric differential and quasi-differential lock driving system are realized through the differential module, and the technical problems of heaviness, high cost, power loss, noise generation, maintenance requirement and the like caused by a mechanical differential are solved.

Drawings

FIG. 1 is a schematic diagram of the electrical connection relationship between the motor windings of the differential and quasi-differential lock system composed of two electric motors in the prior art,

FIG. 2 is a schematic diagram of a prior art double triangle of the system of FIG. 1 in a quasi-differential lock state,

figure 3 is a schematic diagram of a differential module circuit structure according to an embodiment of the present invention,

figure 4 is a schematic diagram of the structure and signal processing mode of a differential lock control module provided by the embodiment of the invention,

figure 5 is a schematic diagram of the steps of a control method of a differential lock control module provided by the embodiment of the invention,

figure 6 is an electronic waveform schematic diagram related to a control method of a differential lock control module provided by the embodiment of the invention,

figure 7 is a schematic diagram of a control method of a differential lock control module according to an embodiment of the present invention relating to a soft loading waveform,

figure 8 is a schematic circuit structure diagram of an electromagnetic relay type differential lock control module provided by the embodiment of the invention,

fig. 9 is one of the schematic structural diagrams of a contactless electronic relay type differential lock module provided by the embodiment of the invention,

fig. 10 is a second schematic structural diagram of a contactless electronic relay type differential lock module according to an embodiment of the present invention.

Detailed Description

In a first aspect, embodiments of the present invention provide a differential lock control module.

Example 1

The differential lock control module is applied to a control circuit of a differential lock motor system, the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, namely each series branch is provided with an end to end and a middle connecting point, the three series branches are connected in a triangular mode according to the end to end connection mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connecting point of the vertex opposite side, and the whole triangle is connected with three switches in total, namely a differential lock switch; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation. Based on the attached fig. 1 and fig. 2 of the background art, the detailed connection relationship, differential principle and differential lock operation refer to the background art.

As shown in fig. 3, the differential lock control module includes three switches, which include three high-power transistors Q1, Q2, Q3, three full-wave rectifier bridges Z1(1001), rectifier bridge Z2(1002), rectifier bridge Z3(1003), three photo-couplers N1, N2, N3, and three gate voltage control circuits G1(2001), G2(2002), G3 (2003). The grid voltage control circuit G1 is provided with A grid voltage power supply end Vb-A, an output end VGO-A, A signal input end In-A and an emitter connecting end Ve-A; the grid voltage control circuit G2 is provided with a grid voltage power supply end Vb-B, an output end VGO-B, a signal input end In-B and an emitter connecting end Ve-B; the gate voltage control circuit G3 has a gate voltage supply terminal Vb-C, an output terminal VGO-C, a signal input terminal In-C and an emitter connection terminal Ve-C.

The photoelectric couplers N1, N2 and N3 are respectively provided with an input end and an output end, the three full-wave rectifier bridges Z1, Z2 and Z3 are respectively provided with two alternating current input ends and two rectification output ends, the two rectification output ends are positive and negative ends, and the output ends of the photoelectric couplers N1, N2 and N3 are respectively connected with signal input ends of gate voltage control circuits G1, G2 and G3.

Emitter connection ends of the grid voltage control circuits G1, G2 and G3 are respectively connected with emitters of three high-power transistors Q1, Q2 and Q3, output ends of the grid voltage control circuits G1, G2 and G3 are respectively connected with grids of three high-power transistors Q1, Q2 and Q3, grid voltage supply ends of the grid voltage control circuits G1, G2 and G3 are used for being connected with three paths of mutually independent grid supply voltages provided by an external circuit, and the grid supply voltages are used for respectively and independently providing grid working voltages for the three high-power transistors Q1, Q2 and Q3.

The emitters of the three high-power transistors Q1, Q2 and Q3 are respectively connected with the negative terminals of the rectification outputs of the three full-wave rectification bridges Z1, Z2 and Z3, the collectors of the three high-power transistors Q1, Q2 and Q3 are respectively connected with the positive terminals of the rectification outputs of the three full-wave rectification bridges Z1, Z2 and Z3, and two alternating current input terminals of the three full-wave rectification bridges Z1, Z2 and Z3 are respectively used for connecting one vertex of a triangle with the middle connection point of the vertex opposite sides.

When the input terminals PAX, PBY and PCZ of the photocouplers N1, N2 and N3 respectively input the conducting signals, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively conducted through the photocouplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, when A high-level signal relative to the photocoupler common reference point VE is input at the PAX terminal, the gate voltage control circuit G1 receives the signal and outputs A high-level signal relative to the emitter of Q1 at the output terminal VGO-A thereof so as to lead the Q1 to be conducted, the output terminal of the rectifier bridge Z1 is short-circuited by the Q1, the AC input terminals A-X of the rectifier bridge are in low internal resistance and are in AC input, therefore the current between the A-X is conducted in two directions, the A-X neutral line switch is conducted, and the other two switches B-Y neutral line and C-Z neutral line are also conducted under the action of the corresponding PBY and PCZ control terminals, the three switches are switched on to realize the function of a differential lock between the output shafts of the two three-phase alternating current motors. Similarly, when the low level is input as the cut-off signal at the input terminals of the photocouplers N1, N2 and N3, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively cut off by the photocouplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, so that the three switches are turned off, and the corresponding phase windings of the two motors are in a series connection relationship, thereby realizing the differential function between the output shafts of the two three-phase alternating current motors.

In a second aspect, a method of controlling a differential lock control module is provided.

Example 2

The control method of the differential lock control module is applied to a control circuit of a differential lock motor system and is matched with the differential lock control module in the embodiment 1 for use; the differential lock motor system further comprises a phase sensing circuit and an electronic control unit ECM, wherein the phase sensing circuit senses the voltage phase of two alternating current input ends of each of three full-wave rectifier bridges Z1, Z2 and Z3, and the electronic control unit ECM has the functions of operation and signal processing and comprises the following steps. As shown in fig. 4 and 5.

Step S1: three voltage phase signals P1, P2 and P3 corresponding to the alternating current input ends of the full-wave rectifier bridges Z1, Z2 and Z3 are obtained through

phase sensing circuits

3001, 3002 and 3003 respectively; the

phase sensing circuits

3001, 3002, and 3003 may be any of a capacitance-resistance detection circuit, an ac transformer detection circuit, and the like.

Step S2: the three acquired voltage phase signals P1, P2 and P3 are transmitted to the electronic control unit ECM, and the three phase signals are differentiated according to the type of the phase sensing circuit, and the specific implementation mode of the phase detection of the alternating current belongs to the prior art, and the invention is not described in detail.

Step S3: the electronic control unit ECM obtains the zero-crossing point time and the electrical angle before and after the zero-crossing point time of the three voltage phase signals P1, P2 and P3 through calculation, as shown in fig. 4, 4001 is an example of a waveform diagram of the phase signal P1, in a small range before and after the zero-crossing point of the waveform, the ECM will output the jump of the rising edge of N1 to turn on the differential lock switch, that is, the conduction time of the differential lock switch falls near the zero-crossing point of the alternating current at the two ends of the switch, and the electrical angle range before and after the zero-crossing point time includes the electrical angle between the zero-crossing point time and the electrical angle between-15 ° and +15 °, which will reduce the conduction turn-on loss of the control switch, and make the motor smoothly switch from the differential relationship to the operation of. Similarly, the ECM operates according to the P1 signal to output the jump of the falling edge of the N1 in a smaller range near the zero crossing point, so that the differential lock switch is switched off, the motor is smoothly switched from the differential lock relation to the differential relation, the self-induced electromotive force between windings at the disconnection time is reduced, the differential lock switch and the motor are protected, the electromagnetic interference is reduced, and the pulse interference on the switch of the power supply is reduced. The processing is the same as described above for signals P2 and P3.

Step S4: when the ECM enters a differential lock state from a differential state according to working condition requirements, the electronic control unit ECM outputs three conducting signals which are respectively transmitted to input ends of three photoelectric couplers N1, N2 and N3, and the electric angle ranges of the starting moments of the three conducting signals before and after the zero-crossing moments of three voltage phase signals P1, P2 and P3 are [ -15 degrees to +15 degrees ], so that output shafts of two three-phase alternating current motors are converted into the differential lock state from the differential state; when the ECM calculates that the differential lock state needs to be converted into the differential state, the electronic control unit ECM outputs three cut-off signals which are respectively transmitted to input ends of three photoelectric couplers N1, N2 and N3, and the starting time of the three cut-off signals is respectively located in an electric angle range of between-15 degrees and +15 degrees before and after the zero-crossing time of three voltage phase signals P1, P2 and P3, so that the two three-phase alternating current motors are converted into the differential state from the differential lock state.

Example 3

A control method of the differential lock control module is also provided.

As shown in fig. 6, in embodiment 2, the on signal duration of the pulse signal (5001) input to the input terminals of the photocouplers N1, N2, and N3 is t1, the off signal duration is t2, the signal period is t1+ t2, the frequency of the external ac power supply (5002 is the waveform thereof) is f1, and when the differential lock switch needs to be turned on, t1+ t2 is equal to or greater than 5/f 1. That is, the signal period t1+ t2 covers at least 5 periods of the external ac power source or more. To prevent frequency interference.

Example 4

A control method of the differential lock control module is also provided.

As shown in fig. 7, on the basis of embodiment 2, the method further includes a differential lock soft loading method: setting the input end of the photocouplers N1, N2 and N3 as the input duration of an on signal t1, the input end of the input signal as t2, the signal period as t1+ t2, controlling three high-power transistors Q1, Q2 and Q3 to be respectively switched on or off through the photocouplers N1, N2 and N3 and gate voltage control circuits G1, G2 and G3, and realizing the difference rate control function between the output shafts of the two three-phase alternating current motors by controlling the conduction rate gamma, wherein the conduction rates gamma of the three switches are t1/(t1+ t 2); the differential lock soft loading method is that the conduction rates gamma of the three switches are t1/(t1+ t2) and are increased step by step, the duration of a pulse t1 at the input end of the optical coupler N1 in fig. 7 is increased step by step, the duration of t2 is reduced step by step, the optical couplers N2 and N3 also adopt the same control mode, so that the conduction duty ratios of the three switches are increased step by step, and the soft loading control function of the differential lock between the output shafts of the two three-phase alternating current motors is realized through gradual adjustment of the conduction rates and the difference rates. Since the signals P1, P2, and P3 are samples of voltage signals at two ends of the three neutral lines, they are similar to the external power source in phase relationship and also satisfy the difference of 120 ° in electrical angle, so in fig. 7, the rising edge start times of the three

soft loading pulses

6001, 6002, and 6003 in the same electrical cycle are different, the start time of T2 lags behind the start time of T1 in the same electrical cycle by 120 ° in electrical angle, and T3 is further delayed by 120 ° in electrical angle.

Similarly to the above soft loading, there is also provided a soft load shedding control method of a differential lock control module, on the basis of embodiment 4: the input on-signal duration of input signals at the input ends of photocouplers N1, N2 and N3 is t1, the input off-signal duration is t2, the signal period is t1+ t2, three high-power transistors Q1, Q2 and Q3 are controlled to be respectively switched on or off through the photocouplers N1, N2 and N3 and gate voltage control circuits G1, G2 and G3, the conduction ratios gamma of three switches are t1/(t1+ t2), and the difference rate control function between the output shafts of the two three-phase alternating current motors is realized through controlling the conduction ratios gamma; the differential lock soft load shedding method is characterized in that the conduction ratios gamma of three switches are t1/(t1+ t2) and are gradually reduced, so that the conduction duty ratios of the three switches are gradually reduced, and the soft load shedding control function of the difference speed between the output shafts of two three-phase alternating current motors is realized through gradual adjustment of the conduction ratios and the difference speed. Obviously, the principle is similar to that of soft loading, and therefore, for the sake of simplicity, the detailed description is omitted, and the waveform diagrams of decreasing duration t1 and increasing duration t2 are not shown in the drawings.

In a third aspect, a differential lock control module is also provided.

The differential lock control module is applied to a control circuit of a differential lock motor system, as shown in fig. 8, the differential lock motor system comprises two three-phase alternating current motors explained in the background art, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total, so that the differential lock switch is called; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation.

The differential lock control module comprises three switches, wherein the three switches comprise three relays RL1, RL2 and RL3, the relays RL1, RL2 and RL3 are contact type electromagnetic relays with control coils respectively, and two contacts of the relays RL1, RL2 and RL3 are used for connecting one vertex of a triangle and a middle connection point of the vertex opposite side respectively.

When the input ends P1, P2 and P3 of control coils of the relays RL1, RL2 and RL3 input conducting signals respectively, two contacts of the relays RL1, RL2 and RL3 are connected with a corresponding point in one vertex of the triangle A, B, C and a middle connecting point X, Y, Z of the opposite side of the vertex respectively, so that the differential lock function between the output shafts of the two three-phase alternating current motors is realized; when the control coils of the relays RL1, RL2 and RL3 input the cutoff signals, the relays RL1, RL2 and RL3 respectively disconnect one vertex of the triangle from the middle connection point of the vertex opposite sides, and the differential function between the output shafts of the two three-phase alternating-current motors is realized. The differential lock module which is simply controlled by the relay can be used in a lower-end control system, so that the circuit structure is simplified, and the cost is reduced. The differential switch can also be combined with an electronic differential lock module, and when the motor is required to output high power and high current in a differential lock mode, the low internal resistance characteristic of a relay contact is utilized for auxiliary control, so that the load of the electronic module is reduced, and the saturation voltage drop loss of the differential switch is reduced. But for the novel power electronic device with low internal resistance, the auxiliary control of a contact relay is not needed.

In a fourth aspect, a differential lock control module is provided.

The differential lock control module is applied to a control circuit of a differential lock motor system, the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular mode according to the end to end connection mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total and called as a differential lock switch; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation.

The differential lock control module comprises three switches, the three switches comprise three relays RL1, RL2 and RL3, the relays RL1, RL2 and RL3 are contactless electronic relays with input ends and two control ends respectively, and the two control ends of the relays RL1, RL2 and RL3 are used for connecting one vertex of a triangle and a middle connection point of the vertex opposite side respectively.

When the input ends of the relays RL1, RL2 and RL3 input the conducting signals, the two control ends of the relays RL1, RL2 and RL3 are respectively connected with a vertex of a triangle and a middle connection point of the vertex opposite sides, so that the differential lock function between the output shafts of the two three-phase alternating current motors is realized; when the input ends of the relays RL1, RL2 and RL3 input the cutoff signals, the relays RL1, RL2 and RL3 respectively disconnect the connection between one vertex of the triangle and the middle connection point of the vertex opposite sides, and the differential function between the output shafts of the alternating current motors is realized.

Two embodiments of differential module circuit configurations are shown in fig. 9 and 10. The contactless relay is composed of an optical coupler N1 and a silicon controlled rectifier SCR1, the contactless relay is composed of an optical coupler N2 and a silicon controlled rectifier SCR2, and the contactless relay is composed of an optical coupler N3 and a silicon controlled rectifier SCR 3. In FIG. 9, when control voltages are input at P1, P2, and P3, the triacs SCR1, SCR2, and SCR3 are turned on to turn on the differential lock switches A-X, B-Y, C-Z.

In fig. 10, when control voltages are input between IA and X, IB and Y, IC and Z, and P1, P2, and P3, triacs SCR1, SCR2, and SCR3 are turned on, respectively, and the differential lock switch between a-X, B-Y, C-Z is turned on.

According to the embodiment, the differential lock and the differential rate control system in the background technology are satisfied, the corresponding functions of the electric differential and quasi-differential lock driving system are realized through the differential module, and the technical problems of heaviness, high cost, power loss, noise generation, maintenance requirement and the like caused by a mechanical differential are solved.

The embodiments of the present invention are only used for illustrating the technical solutions of the present invention, and are not limited to the present invention, and the combination of the embodiments of the present invention or other embodiments obtained by equivalent replacement and non-inventive work may fall within the scope of the present invention without departing from the inventive concept disclosed in the technical solutions of the present invention, and the scope of the present invention is defined by the appended claims.

Claims

1. A differential lock control module is applied to a control circuit of a differential lock motor system, the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, namely each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular mode according to the end to end connection mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in total, so that the differential lock switch is called; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that:

the differential lock control module comprises three high-power transistors Q1, Q2, Q3, three full-wave rectifier bridges Z1, Z2, Z3, three photoelectric couplers N1, N2, N3 and a switch control circuit consisting of three grid voltage control circuits G1, G2 and G3, wherein,

when on-signals are input to the input ends of the photocouplers N1, N2 and N3, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively switched on through the photocouplers N1, N2 and N3 and the grid voltage control circuits G1, G2 and G3, and the differential lock function between the output shafts of the two three-phase alternating current motors is realized through the rectification bridge connection; when cutoff signals are input to the input ends of the photocouplers N1, N2 and N3, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively cut off through the photocouplers N1, N2 and N3 and the grid voltage control circuits G1, G2 and G3, and the differential function between the output shafts of the two three-phase alternating-current motors is achieved through a rectifier bridge.

2. A control method of a differential lock control module is applied to a control circuit of a differential lock motor system and is matched with the differential lock control module in claim 1 for use; the differential lock motor system also comprises a phase sensing circuit and an electronic control unit ECM, wherein the phase sensing circuit senses the phase of alternating voltage at two ends of each differential lock switch, and the electronic control unit ECM has the functions of operation and signal processing and is characterized by comprising the following steps of,

step S4: when the ECM enters a differential lock state from a differential state as required, the electronic control unit ECM outputs three conducting signals which are respectively transmitted to input ends of three photoelectric couplers N1, N2 and N3, and the electric angle ranges of the starting moments of the three conducting signals before and after the zero-crossing moments of three voltage phase signals P1, P2 and P3 are [ -15 degrees to +15 degrees ], so that the output shafts of the two three-phase alternating current motors are converted into the differential lock state from the differential state; when the ECM calculates that the two three-phase alternating current motors need to be switched from the differential lock state to the differential state, the electronic control unit ECM outputs three cut-off signals which are respectively transmitted to the input ends of the three photoelectric couplers N1, N2 and N3, and the electric angle ranges of the starting moments of the three cut-off signals before and after the zero-crossing moments of the three voltage phase signals P1, P2 and P3 are between-15 degrees and +15 degrees, so that the two three-phase alternating current motors are switched from the differential lock state to the differential state.

3. The method for controlling the differential lock control module according to claim 2, wherein the time duration of the on signal inputted at the input terminals of the photocouplers N1, N2, and N3 is t1, the time duration of the off signal inputted is t2, the signal period is t1+ t2, the frequency of the external ac power supply is f1, and when the differential lock switch is required to be turned on, the t1+ t2 is made to be not less than 5/f 1.

4. The control method of the differential lock control module according to claim 2, further comprising a differential lock soft loading method: the input end of the photoelectric couplers N1, N2 and N3 is provided with an input on-signal duration t1, an input off-signal duration t2 and a signal period t1+ t2, the three high-power transistors Q1, Q2 and Q3 are controlled to be respectively switched on or off by the photoelectric couplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, the conduction rate gamma on a neutral line is controlled to be t1/(t1+ t2) by the rectifier bridge, and the difference rate control function between the output shafts of the two three-phase alternating current motors is realized by controlling the conduction rate gamma; the soft loading method of the differential lock comprises the steps of controlling the conduction rate gamma to be t1/(t1+ t2) to be increased step by step, enabling the conduction duty ratio on the neutral line to be increased step by step, and achieving the soft loading control function of the differential lock between the output shafts of the two three-phase alternating current motors through gradual adjustment of the conduction rate and the difference rate.

5. The control method of the differential lock control module according to claim 2, further comprising a differential lock soft relief method: the input on-signal duration and the input off-signal duration of the photocouplers N1, N2 and N3 are t1, t2 and t1+ t2 respectively, the three high-power transistors Q1, Q2 and Q3 are controlled to be switched on or off respectively through the photocouplers N1, N2 and N3 and the gate voltage control circuits G1, G2 and G3, the on and off of a neutral line are controlled through the rectifier bridge, the on-off rate gamma of the neutral line is t1/(t1+ t2), and the differential rate control function between the output shafts of the two three-phase alternating current motors is realized through the control of the on-off rate gamma; the differential lock soft load shedding method is characterized in that the conduction rate gamma is controlled to be t1/(t1+ t2) to be gradually reduced, the conduction duty ratio on a neutral line is gradually reduced, and the soft load shedding control function of the difference rate between the output shafts of the two three-phase alternating current motors is realized through gradual adjustment of the conduction rate and the difference rate.

6. A differential lock control module is applied to a control circuit of a differential lock motor system, the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular mode according to the end to end connection mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in common, so that the differential lock switch is called; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that:

7. A differential lock control module is applied to a control circuit of a differential lock motor system, the differential lock motor system comprises two three-phase alternating current motors, corresponding phase windings of the two three-phase alternating current motors are connected in series end to form three series branches, each series branch is provided with an end to end and a middle connection point, the three series branches are connected in a triangular mode according to the end to end connection mode, three vertexes of the connected triangle are used for being connected with an external three-phase alternating current power supply, a switch is connected between each vertex of the triangle and the middle connection point of the vertex opposite side, and the whole triangle is connected with three switches in common, so that the differential lock switch is called; when the differential lock switch is in an off state, the output shafts of the two three-phase alternating current motors are in a differential relation, and when the differential lock switch is in an on state, the output shafts of the two three-phase alternating current motors are in a differential lock relation, and the differential lock switch is characterized in that: