Large-torque wide-speed-regulation permanent magnet torque spindle motor

Abstract

The invention relates to the technical field of motors, and discloses a large-torque wide-speed-regulation permanent magnet torque spindle motor which comprises a machine shell and a spindle arranged in the machine shell. The respective multi-phase wire outlet ends of the n permanent magnet power modules are symmetrically connected; each permanent magnet power module comprises one or more permanent magnet driving subunits, and all the permanent magnet driving subunits are sequentially arranged in the axial direction of the main shaft; at least one permanent magnet power module Mi except the permanent magnet power module M1 is provided with bypass branches Qi which are connected in parallel; the wire inlet end of the permanent magnet power module M1 is connected with a power supply, and a control unit Si is arranged between the wire outlet end of the multi-phase coil winding of each permanent magnet power module Mi except the permanent magnet power module Mn and the corresponding neutral point Oi. And each control unit Si selects to connect part or all of the permanent magnet power modules in series so as to drive the main shaft, so that the motor can output rotating speed and torque which can be adjusted within a relatively large range.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a large-torque and wide-speed-regulating permanent-magnet torque spindle motor. Background Art

[0002] The stator structure of traditional DC motors is fixed, and the final output performance of DC motors is determined accordingly. With the rapid development of precision CNC machine tools in recent years, DC motors are used to provide driving force. Precision CNC machine tools have different requirements for the output characteristics of DC motors under different working conditions, resulting in the need to replace DC motors with different characteristics to meet the requirements.

[0003] In order to meet the driving requirements of precision CNC machine tools, DC motors with adjustable motor torque have emerged. For example, the technical solution disclosed in China CN208767879U uses multi-phase windings connected in parallel, and each phase winding includes multiple coil groups connected in parallel. The number of parallel windings is controlled to meet the speed and torque requirements under various working conditions. However, the motor of this technical solution has the following shortcomings: 1. The current of each parallel circuit is large, which will lead to a large total current in the main circuit, and thus occupy the current resources of the DC motor external driver, requiring the driver to have a large current output capacity.

[0004] 2. When any of the parallel coil groups is disconnected, the corresponding windings will not be energized and cannot act on the magnetic track, which will cause the additional torque generated by the coil group on the magnet to be uneven, and then cause the rotor to become unstable and not smooth during rotation, which cannot meet the requirements of the DC motor in a high-precision use environment.

[0005] 3. The adjustable range of speed and torque is small, which makes it difficult to meet the driving requirements of the motor under various working conditions. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art and proposes a large torque and wide speed regulation permanent magnet torque spindle motor, wherein the adjustable range of speed and torque is large so that the motor can meet the driving requirements under various working conditions.

[0007] The present invention provides a large torque and wide speed regulation permanent magnet torque spindle motor, which comprises: A casing and a main shaft disposed in the casing; n permanent magnet power modules M1, M2, ... and M n , the multi-phase output terminals of each permanent magnet power module are connected symmetrically; Each permanent magnet power module includes one or more permanent magnet drive sub-units, the total number of all permanent magnet drive sub-units is k, each permanent magnet drive sub-unit includes a permanent magnet rotor fixedly connected to the main shaft and a stator coil for driving the permanent magnet rotor to rotate, and the stator coil includes a multi-phase coil winding; k permanent magnet drive sub-units are arranged in sequence in the axial direction of the main shaft, and any two permanent magnet drive sub-units do not interfere with each other's driving of the main shaft; At least one of the permanent magnet power modules M except the permanent magnet power module M1 i Bypass branch Q with parallel connection i , bypass branch Q i One end of the permanent magnet power module M i The outgoing terminal is connected to the branch Q i The other end is set as a bypass terminal, which is opposite to the permanent magnet power module M i The incoming line terminal is connected and suspended; The incoming line end of the permanent magnet power module M1 is connected to the power supply. n Other permanent magnet power modules M i The output terminals of the respective multi-phase coil windings are connected to the respective corresponding neutral points O i There are control units S i , each control unit S i Corresponding to the permanent magnet power module M i The outlet terminal and the neutral point O i 、Permanent magnet power module M i+1 The incoming line end and the bypass branch Q i+1 The permanent magnet power modules M1, M2, ... and M n Some or all of them are connected in series to drive the main shaft; Wherein, n is a natural number greater than 2, i is a natural number less than n, and k is a natural number greater than or equal to n.

[0008] In some preferred embodiments, each permanent magnet drive sub-unit has the same specifications, and the multi-phase coil windings corresponding to the multiple permanent magnet drive sub-units arranged in the same permanent magnet power module are connected in series in sequence.

[0009] In some preferred embodiments, each control unit S i Coordinated selection of j number of permanent magnet drive sub-units connected in series, when the motor runs to the maximum rated power P0, the motor output speed R j and torque T j The coefficient j changes inversely, so that the speed and torque output by the motor can be adjusted within a wide range; Among them, the speed R j and torque Tj They are: R j =R1 / j,T j =j*T1, R1 and T1 are the maximum speed and minimum torque output by the motor when only one permanent magnet drive sub-unit drives the spindle, and j is a natural number less than k.

[0010] In some preferred embodiments, by each control unit S i When k permanent magnet drive sub-units are selected in series, the minimum speed R is output when the motor runs to the maximum rated power P0. k and maximum torque T k， R k =R1 / k,T k =k*T1.

[0011] In some preferred embodiments, the control unit S i Includes one of an IGBT transistor, a MOS transistor, a relay and a contactor.

[0012] In some preferred embodiments, it also includes a control unit S i The connected controller controls each control unit S i Electrical action.

[0013] In some preferred embodiments, a current driver connected to the line input terminal of the permanent magnet power module M1 is also included.

[0014] In some preferred embodiments, the bypass branch Q i For the wire, in the control unit S i-1 The permanent magnet power module M i The outlet terminal and the bypass branch Q i When the bypass terminal is connected, the permanent magnet power module M i Not connected in series with the permanent magnet power module M1.

[0015] In some preferred embodiments, n=4, k=8, the permanent magnet power modules M1 and M2 each include one permanent magnet drive sub-unit, and the permanent magnet power modules M3 and M4 each include three permanent magnet drive sub-units connected in series.

[0016] In some preferred embodiments, only the permanent magnet power module M2 is connected in parallel with the bypass branch Q2.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts a plurality of permanent magnet drive sub-units connected in series to jointly drive the main shaft. The speed and torque output characteristics of the motor can be adjusted by selecting the number j of the permanent magnet drive sub-units connected in series, and the speed and torque output by the motor vary inversely with the number j of the permanent magnet drive sub-units connected in series as a coefficient, so that the speed and torque output by the motor can be adjusted within a larger range, so that the motor can output both high speed and large torque, so that the motor can meet the driving requirements under various working conditions.

[0018] 2. Since each permanent magnet drive sub-unit is connected in series, the number of permanent magnet drive sub-units connected in series should not affect the driving current of the motor. Therefore, when a larger number of permanent magnet drive sub-units are rotated in series to allow the motor to obtain a large torque output, the driving current requirement of the current driver will not increase, thereby reducing the current capacity requirement of the permanent magnet torque spindle motor for the current driver.

[0019] 3. Since each permanent magnet drive sub-unit is arranged in sequence in the axial direction of the main shaft, each permanent magnet drive sub-unit includes a permanent magnet rotor fixedly connected to the main shaft and a stator coil for driving the permanent magnet rotor to rotate. Therefore, in the process of realizing torque and speed regulation by selecting the number of permanent magnet drive sub-units connected in series, the permanent magnet rotors are evenly arranged 360 degrees relative to the main shaft, which is beneficial to ensure the reliability and stability of the motor operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional structural schematic diagram of the permanent magnet torque spindle motor disclosed in the present invention.

[0021] Figure 2 It is a schematic diagram of a portion of the internal structure of the permanent magnet torque spindle motor disclosed in the present invention.

[0022] Figure 3 It is a schematic diagram of electrical connections of various permanent magnet drive sub-units in the permanent magnet torque spindle motor disclosed in the present invention.

[0023] Figure 4 It is a schematic diagram of the torque-speed curve of the permanent magnet torque spindle motor.

[0024] Figure 5 yes Figure 3 A schematic diagram of electrical connections of an embodiment.

[0025] Figure 6 yes Figure 5 Schematic diagram of the torque-speed curve of the permanent magnet torque spindle motor in the embodiment.

[0026] Figure 7 yes Figure 5 Schematic diagram of the power-speed curve of the permanent magnet torque spindle motor in the embodiment. DETAILED DESCRIPTION

[0027] In order to further explain the technical means and effects adopted by the present application to achieve the predetermined purpose, the specific implementation methods, structures, features and effects of the present application are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0028] In the formulas given in this application, the symbol * represents a multiplication operation, and the symbol / represents a division operation.

[0029] Combination Figure 1 and Figure 2 As shown, the present invention discloses a large torque wide speed regulation permanent magnet torque spindle motor (referred to as "permanent magnet torque spindle motor" or "motor"), comprising a housing 1, a spindle 2 arranged in the housing 1, and k permanent magnet drive sub-units 3 coaxially arranged in sequence in the axial direction of the spindle 2, and any two permanent magnet drive sub-units 3 do not interfere with each other's driving of the spindle 2. One end of the spindle 2 passes through the housing 1 and has a connecting shaft 21, which is connected to other machine tools through the connecting shaft 21 to drive other machine tools to work.

[0030] Each permanent magnet drive subunit 3 is actually equivalent to an independent sub-motor for driving the main shaft 2. Each permanent magnet drive subunit 3 includes a permanent magnet rotor 31 fixedly connected to the main shaft 2 and a stator coil 32 for driving the permanent magnet rotor 31 to rotate, and the stator coil 32 includes a multi-phase coil winding.

[0031] The present invention uses some or all of the k permanent magnet drive sub-units 3 connected in series to drive the spindle 2, so that the output speed and torque of the spindle 2 can be adjusted within a large range, so that the permanent magnet torque spindle motor can meet the driving requirements under various working conditions when driving different machine tools.

[0032] The permanent magnet drive sub-units 3 are connected in series, which means that two or more permanent magnet drive sub-units 3 are connected in series, and the multi-phase coil windings of each permanent magnet drive sub-unit 3 are connected in series in sequence.

[0033] Further integration Figure 3 As shown in FIG. 1 , it is a schematic diagram of the electrical connection of each permanent magnet drive subunit in the permanent magnet torque spindle motor. In order to reduce the wiring complexity when some or all of the permanent magnet drive subunits 3 are connected in series one by one, in some preferred embodiments, one or more permanent magnet drive subunits 3 are pre-assembled into a permanent magnet power module. That is, in the permanent magnet torque spindle motor of the present invention, the housing 1 is coaxially provided with n permanent magnet power modules M1, M2, ... and M2 in the axial direction of the spindle 2. n , n is a natural number greater than 2, and k is a natural number greater than or equal to n.

[0034] For the convenience of description, the two opposite ends of the main shaft 2 in the axial direction are defined as the head end and the tail end. Therefore, the connecting shaft 21 is fixed to the head end or the tail end of the main shaft 2, which is not limited here. The permanent magnetic power module at the head end is M1, and the permanent magnetic power module at the tail end is M n .

[0035] Furthermore, each permanent magnet power module includes one or more permanent magnet drive sub-units, and the multi-phase outlet terminals of each permanent magnet power module adopt one of the symmetrical connections, for example, a star connection is adopted to be connected at the neutral point O. When the permanent magnet power module includes only one permanent magnet drive sub-unit, the inlet terminal and outlet terminal of the permanent magnet drive sub-unit are respectively the inlet terminal and outlet terminal of the permanent magnet power module. When the permanent magnet power module includes multiple permanent magnet drive sub-units, the inlet terminal of a permanent magnet drive sub-unit near the head end of the permanent magnet power module is the inlet terminal of the permanent magnet power module, and the inlet terminal of a permanent magnet drive sub-unit near the tail end is the outlet terminal of the permanent magnet power module.

[0036] All k permanent magnet drive sub-units are arranged in sequence in the axial direction of the spindle, and any two permanent magnet drive sub-units 3 do not interfere with each other's driving of the spindle 2. In addition, each permanent magnet drive sub-unit 3 is set to the same specification. Furthermore, the multi-phase coil windings corresponding to the multiple permanent magnet drive sub-units arranged in the same permanent magnet power module are connected in series in sequence. Such a structure can enable the permanent magnet torque spindle motor to obtain a smoother torque-speed curve, and the torque and speed output by the permanent magnet torque spindle motor can be adjusted in a larger range to meet the driving requirements of a large processing range.

[0037] It is understandable that the number of phases of the power supply, the number of phases of each permanent magnet power module and the number of phases of each permanent magnet drive sub-unit are the same. The specification and drawings of this application are all described when the power supply, each permanent magnet power module and each permanent magnet drive sub-unit are three-phase. In this case, each permanent magnet drive sub-unit includes a three-phase coil.

[0038] Specifically, in some preferred embodiments, in order to meet the needs of adjusting the output torque and speed of the permanent magnet torque spindle motor, the permanent magnet power module M1 has only one permanent magnet drive subunit, and its three-phase coil windings are respectively recorded as U1, V1 and W1; the permanent magnet power module M2 also has only one permanent magnet drive subunit, and its three-phase coil windings are respectively recorded as U2, V2 and W2; and the other permanent magnet power modules M after the permanent magnet power module M2 are respectively recorded as U1, V1 and W2. n It can be set as one or more permanent magnet drive sub-units as required.

[0039] For example Figure 3 As shown, the permanent magnet power module M n-1Suppose there are y permanent magnet power modules, y is a natural number greater than 1, where the three-phase coil winding U （n-1）1 、V （n-1）1 and W （n-1）1 It is a permanent magnet drive subunit near the head end, with a three-phase coil winding U （n-1）1 、V （n-1）1 and W （n-1）1 The incoming line end is used as the permanent magnet power module M n-1 The incoming line end; with three-phase coil winding U （n-1）y 、V （n-1）y and W （n-1）y The outlet terminal is used as the permanent magnet power module M n-1 The outlet terminal of the permanent magnet power module M n-1 The three-phase outgoing line terminals are connected in star connection at the neutral point Q n-1 Similarly, the three-phase coil winding U （n-1）y 、V （n-1）y and W （n-1）y It is a permanent magnet drive subunit near the tail end, the permanent magnet power module M n Suppose there are x permanent magnet power modules, x is a natural number greater than 1, permanent magnet power module M n The three-phase output terminal is the three-phase coil winding U nx 、V nx and W nx The three are connected in star connection at the neutral point Q n .

[0040] Furthermore, at least one of the permanent magnet power modules M1 other than the permanent magnet power module M i With a bypass branch Q connected in parallel therewith i , bypass branch Q i One end of the permanent magnet power module M i The outgoing terminal is connected to the branch Q i The other end is set as a bypass terminal, which is opposite to the permanent magnet power module M i The incoming line terminal is connected to the floating setting, i is a natural number less than n. That is to say, in the permanent magnet power module M2 to M n At least one of the permanent magnet power modules M i With a bypass branch Q connected in parallel therewith i For example, the permanent magnet power module M2 has a bypass branch Q2 connected in parallel therewith, and the permanent magnet power module M3 also has a bypass branch Q3 connected in parallel therewith.

[0041] The incoming line end of the permanent magnet power module M1 is connected to the power supply. n Other permanent magnet power modules M i, the output terminals of their respective multi-phase coil windings are connected to their respective corresponding neutral points O i There are control units S i , that is, the permanent magnet power modules M1, M2, ... and M n-1 The output terminals of the respective multi-phase coil windings are connected to the respective corresponding neutral points O1, O2, ... and O n-1 There are control units S1, S2, ... and S n-1 .

[0042] Control unit S i Used to select the permanent magnet power module M i The outlet terminal and the neutral point O i 、Permanent magnet power module M i+1 The incoming line end and the bypass branch Q i+1 One of the three side terminals is connected to connect the permanent magnet power modules M1, M2... and M n Some or all of them are connected in series to drive the main shaft, and i is a natural number less than n.

[0043] Among them, the bypass branch Q i For the wire, in the control unit S i-1 The permanent magnet power module M i The outlet terminal and the bypass branch Q i When the bypass terminal is connected, the permanent magnet power module M i Not connected in series with the permanent magnet power module M1.

[0044] For example, a bypass branch Q2 connected in parallel with the permanent magnet power module M2 is usually provided in the permanent magnet power module M2, so that the bypass branch Q2 can be used to connect the permanent magnet power module M2, or the permanent magnet power module M2... and M n , all choose not to be connected in series with the permanent magnet power module M1.

[0045] The control unit S i It includes one of an IGBT transistor, a MOS transistor, a relay and a contactor, but is not limited here.

[0046] Of course, the permanent magnet torque spindle motor can also include various control units S i The connected controller controls each control unit S i The electrical state of each control unit S i Can connect corresponding permanent magnet power module M in series as needed i .

[0047] Furthermore, the line inlet of the permanent magnet power module M1 at the head end is connected to the power supplies U, V and W. Usually, a power switch is provided between the permanent magnet power module M1 and the power supply. Of course, the power switch can also be integrated with the control unit S1.

[0048] In addition, the permanent magnet torque spindle motor also includes a current driver connected to the input terminal of the permanent magnet power module M1. i One or more permanent magnet drive sub-units connected to drive the spindle 2 are connected in series. No matter how many permanent magnet drive sub-units are selected to drive the spindle 2, only the output characteristics of the permanent magnet torque spindle motor will be changed, and the driving current requirements of the current driver will not be increased, thereby reducing the current capacity requirements of the permanent magnet torque spindle motor for the current driver.

[0049] Further integration Figure 4 Schematic diagram of the torque-speed curve output by the permanent magnet torque spindle motor. The present invention uses each control unit S i Working together, select some or all of the permanent magnet power modules to be connected in series and then connected to the power supply, that is, through each control unit S i The number of permanent magnet drive sub-units connected in series is controlled in coordination to jointly drive the spindle, so that the torque and speed output characteristics of the permanent magnet torque spindle motor can be adjusted within a wide range to meet the driving power requirements for processing in a wide range. The working principle is as follows: Since the equivalent resistance and current of the permanent magnet motor are small when it is working, the back electromotive force E0 generated by the permanent magnet motor when it is working is close to the input voltage U applied by the power supply to the motor. in ,Right now: E0≈U in (1) The back EMF of the motor E0 is determined by the motor speed R, magnetic flux B and winding length L, that is: E0=B*L*R (2) The magnetic flux B is related to the magnetic track of the rotor of the permanent magnet drive subunit. For ease of understanding, the magnetic flux B and the winding length L are assumed to be constant values.

[0050] The relationship between the motor output speed R and the radius r and angular velocity ω of the spindle 2 is as follows: R = r * ω (3) That is, the linear speed of the spindle 2 is the rotation speed R output by the motor, and the radius R of the spindle 2 is a constant value.

[0051] At the same time, the relationship between the maximum rated power P0 of the motor, the speed R output by the motor, and the torque T output by the motor is as follows: P0=T*ω=T*R / r (4) According to formula (4), when the motor is working at the maximum rated power, the motor output speed R is inversely proportional to the motor output torque T. When the motor outputs the highest speed, the corresponding output torque is the smallest. Conversely, when the motor outputs the lowest speed, the corresponding output torque is the largest.

[0052] When the control unit S1 is connected to the neutral point O1, only the permanent magnet power module M1 is connected to the power supply. At this time, only one permanent magnet drive subunit drives the main shaft to rotate. At this time, the back electromotive force E1 generated by the permanent magnet drive subunit is E0. At this time, the motor output speed R1 is the maximum but the torque T1 is the minimum. When the motor runs to the maximum rated power P0, its output characteristic is in Figure 4 Point a1 in .

[0053] When the control unit S1 is connected to the incoming line of the permanent magnet power module M2, and the control unit S2 to S n Connect the output terminals of permanent magnet power modules M2 to M2 to the corresponding neutral points O2 to Q n When connected, assuming that the permanent magnet power module M2 also contains only one permanent magnet drive sub-unit, at this time, the permanent magnet power module M1 is connected in series with the permanent magnet power module M2, and the two permanent magnet drive sub-units are connected in series to jointly drive the spindle. At the same time, each permanent magnet drive sub-unit has the same specifications, and each permanent magnet drive sub-unit is arranged in sequence in the axial direction of the spindle, and any two permanent magnet drive sub-units do not interfere with each other's drive of the spindle. Therefore, the two permanent magnet drive sub-units connected to the power supply each generate a back electromotive force E2=E0 / 2. Using formula (2), it can be seen that when the two series-connected permanent magnet drive sub-units jointly drive the spindle, the motor output speed R2=R1 / 2. At the same time, according to formula (4), it can be seen that the motor output speed T2=2*T1 at this time. When the motor runs to the maximum rated power P0, its output characteristic is in Figure 4 Point a2 in .

[0054] When each control unit S i Collaborate to make all permanent magnet power modules M1 to M n When all are connected in series and connected to the power supply, assuming that all permanent magnet power modules M1 to M n The total number of permanent magnetic drive subunits included is k, where k is a natural number greater than n. Then, these k permanent magnetic drive subunits are all connected in series and jointly drive the main shaft to rotate. At this time, the back electromotive force E generated by each permanent magnetic drive subunit is k =E0 / k, using formula (2) we can know the motor output speed R k =R1 / k; at the same time, according to formula (4), it can be known that the torque T output by the motor at this time k =k*T1, when the motor runs to the maximum rated power P0, its output characteristic is Figure 4 a k point. At this time, the speed R k , torque T k They are the minimum speed and maximum torque output by the motor respectively.

[0055] Therefore, when each control unit S iBy collaboratively selecting the number j of permanent magnet drive subunits connected in series and connected to the power supply, where j is a natural number less than k, the motor output speed R can be changed. j And the corresponding torque T j When the motor runs to the maximum rated power P0, its output characteristic is Figure 4 a j Point, speed R j =R1 / j, torque T j =j*T1.

[0056] Since each permanent magnet drive sub-unit has the same specifications, through each control unit S i When different numbers of permanent magnet drive sub-units are selected in series to jointly drive the spindle, Figure 4 a1, a2… and a k The torque-speed curve formed by connecting and fitting each point in sequence is an approximate smooth straight line, which means that the output speed R and torque T of the motor can be adjusted as needed within a large range.

[0057] For easier understanding, further combined Figure 5 As shown, in an actual application, the permanent magnet torque spindle motor includes 4 permanent magnet power modules M1 to M4 and a total of 8 permanent magnet drive sub-units. The 8 are coaxially arranged on the spindle 2 in sequence, each permanent magnet drive sub-unit 3 is of the same specification, and any two permanent magnet drive sub-units 3 do not interfere with each other's drive on the spindle.

[0058] The permanent magnet power module M1 includes the first permanent magnet drive subunit, whose three-phase coil windings are denoted as U1, V1 and W1, and whose three-phase outgoing terminals are connected to the neutral point O1. A control unit S1 is provided between the outgoing terminal of the permanent magnet power module M1 and the neutral point O1, and the control unit S1 can select one of the three, the neutral point O1, the incoming terminal of the permanent magnet power module M2 and the bypass terminal of the bypass branch Q2, to be connected as needed.

[0059] The permanent magnet power module M2 includes a second permanent magnet drive subunit, whose three-phase coil windings are denoted as U2, V2 and W3, and whose three-phase outgoing terminals are connected to the neutral point O2; a parallel bypass branch Q2 is provided in the permanent magnet power module M2. A control unit S2 is provided between the outgoing terminal of the permanent magnet power module M2 and the neutral point O2, and the control unit S2 can select to connect the neutral point O2 or the incoming terminal of the permanent magnet power module M2 as needed.

[0060] The permanent magnet power module M3 includes the third permanent magnet drive subunit (its three-phase coil windings are marked as U3, V3 and W3), the fourth permanent magnet drive subunit (its three-phase coil windings are marked as U4, V4 and W4) and the fifth permanent magnet drive subunit (its three-phase coil windings are marked as U5, V5 and W5) which are connected in series in sequence, and their three-phase output terminals are connected to the neutral point O3. A control unit S3 is provided between the output terminal of the permanent magnet power module M3 and the neutral point O3, and the control unit S3 can select to connect the neutral point O3 or the input terminal of the permanent magnet power module M4 as needed.

[0061] The permanent magnet power module M4 includes the 6th permanent magnet drive sub-unit (whose three-phase coil windings are denoted as U6, V6 and W6), the 7th permanent magnet drive sub-unit (whose three-phase coil windings are denoted as U7, V7 and W7) and the 8th permanent magnet drive sub-unit (whose three-phase coil windings are denoted as U8, V8 and W8) connected in series in sequence, and their three-phase output terminals are connected to the neutral point O4.

[0062] According to the driving requirements of the permanent magnet torque spindle motor for different processing conditions, the various control units S1 to S4 can be controlled to work together, and part or all of the four permanent magnet power modules M1 to M4 can be selected to drive the spindle 2, so that the permanent magnet torque spindle motor can output the torque and speed applicable to the driving requirements as needed within a larger adjustable range.

[0063] Further integration Figure 6 and Figure 7 For example, when the control unit S1 is connected to the neutral point O1, only the first permanent magnet drive subunit drives the spindle. When the motor runs to the maximum rated power P0, its output characteristic is Figure 6 At point a1 in the figure, the output speed is 3000 rpm and the output torque is 70 Nm. At this time, the motor output characteristic is high speed and low torque, which is suitable for driving other machine tools for milling operations.

[0064] When the control unit S1 is connected to the incoming line terminal of the permanent magnet power module M2, and the control unit S2 connects the outgoing line terminal of the permanent magnet power module M2 to the neutral point O2, the first permanent magnet drive subunit and the second permanent magnet drive subunit are connected in series to jointly drive the main shaft. When the motor runs to the maximum rated power P0, its output characteristic is in Figure 6 At point a2 in the figure, the output speed is 1500 rpm and the output torque is 140Nm.

[0065] When the control unit S1 is connected to the bypass branch Q2, and the control unit S3 connects the output terminal of the permanent magnet power module M3 to the neutral point O3, the 1st and 3rd to 5th permanent magnet drive sub-units are connected in series, and the main shaft is driven by the four permanent magnet drive sub-units together. When the motor runs to the maximum rated power P0, its output characteristic is in Figure 6 At point a3 in the figure, the output speed is 750 rpm and the output torque is 280 Nm.

[0066] When the motor is at point a2 or a3, it can choose to output a higher speed or a larger torque, which is suitable for driving other machine tools to perform turning and milling operations.

[0067] If the control units S1 to S3 are connected to the incoming terminals of the permanent magnet power modules M2 to M3 respectively, the 1st to 8th permanent magnet drive sub-units are connected in series in sequence to drive the main shaft together. When the motor runs to the maximum rated power P0, its output characteristic is Figure 6 At point a4 in the figure, the output speed is 375 rpm and the output torque is 560 Nm. At this time, the motor output characteristic is large torque, which is suitable for driving other machine tools for turning operations.

[0068] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. Large torque and wide speed regulation permanent magnet torque spindle motor, characterized by: include: A casing and a main shaft disposed in the casing; n permanent magnet power modules M1, M2, ... and M n , the multi-phase output terminals of each permanent magnet power module are connected symmetrically; Each permanent magnet power module includes one or more permanent magnet drive sub-units, the total number of all permanent magnet drive sub-units is k, each permanent magnet drive sub-unit includes a permanent magnet rotor fixedly connected to the main shaft and a stator coil for driving the permanent magnet rotor to rotate, and the stator coil includes a multi-phase coil winding; k permanent magnet drive sub-units are arranged in sequence in the axial direction of the main shaft, and any two permanent magnet drive sub-units do not interfere with each other's driving of the main shaft; At least one of the permanent magnet power modules M except the permanent magnet power module M1 i Bypass branch Q with parallel connection i , bypass branch Q i One end of the permanent magnet power module M i The outgoing terminal is connected to the branch Q i The other end is set as a bypass terminal, which is opposite to the permanent magnet power module M i The incoming line terminal is connected and suspended; The incoming line end of the permanent magnet power module M1 is connected to the power supply. n Other permanent magnet power modules M i The output terminals of the respective multi-phase coil windings are connected to the respective corresponding neutral points O i There are control units S i , each control unit S i Corresponding to the permanent magnet power module M i The outlet terminal and the neutral point O i 、Permanent magnet power module M i+1 The incoming line end and the bypass branch Q i+1 The permanent magnet power modules M1, M2, ... and M n Some or all of them are connected in series to drive the main shaft; Wherein, n is a natural number greater than 2, i is a natural number less than n, and k is a natural number greater than or equal to n.

2. According to claim 1, the large torque and wide speed regulation permanent magnet torque spindle motor is characterized in that: Each permanent magnet drive sub-unit has the same specification, and the multi-phase coil windings corresponding to the multiple permanent magnet drive sub-units arranged in the same permanent magnet power module are connected in series in sequence.

3. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 1 is characterized in that: Through each control unit S i Coordinated selection of j number of permanent magnet drive sub-units connected in series, when the motor runs to the maximum rated power P0, the motor output speed R j and torque T j The coefficient j changes inversely, so that the speed and torque output by the motor can be adjusted within a wide range; Among them, the speed R j and torque T j They are: R j =R1 / j,T j =j*T1, R1 and T1 are the maximum speed and minimum torque output by the motor when only one permanent magnet drive sub-unit drives the spindle, and j is a natural number less than k.

4. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 3 is characterized in that: Through each control unit S i When k permanent magnet drive sub-units are selected in series, the minimum speed R is output when the motor runs to the maximum rated power P0. k and maximum torque T k， R k =R1 / k,T k =k*T1.

5. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 1 is characterized in that: Control unit S i Includes one of an IGBT transistor, a MOS transistor, a relay and a contactor.

6. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 5, characterized in that: Also includes each control unit S i The connected controller controls each control unit S i Electrical action.

7. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 1, characterized in that: It also includes a current driver connected to the line-in terminal of the permanent magnet power module M1.

8. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 1, characterized in that: Bypass branch Q i For the wire, in the control unit S i-1 The permanent magnet power module M i The outlet terminal and the bypass branch Q i When the bypass terminal is connected, the permanent magnet power module M i Not connected in series with the permanent magnet power module M1.

9. The large torque and wide speed regulation permanent magnet torque spindle motor according to any one of claims 1 to 8, characterized in that: n=4, k=8, the permanent magnet power modules M1 and M2 each include one permanent magnet drive sub-unit, and the permanent magnet power modules M3 and M4 each include three permanent magnet drive sub-units connected in series.

10. The large torque and wide speed regulation permanent magnet torque spindle motor according to claim 9, characterized in that: Only the permanent magnet power module M2 is connected in parallel with the bypass branch Q2.

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