CN209748383U - Servo motor and electric automobile - Google Patents

Abstract

A servo motor and an electric automobile comprise a stator and a rotor arranged on the periphery of the stator, wherein a stator iron core is provided with a plurality of pole shoes which protrude outwards along the radial direction of the stator and are arranged at equal intervals along the circumferential direction, a plurality of first armature windings and a plurality of second armature windings are wound on the pole shoes, the rotor comprises a cylindrical permanent magnet fixing frame and a driving cylinder which is provided with teeth along the circumferential direction, a plurality of slots which are arranged at equal intervals are arranged on the fixing frame, the part of the slots in the fixing frame extends along the axial direction and the section is in a fan shape, the part at the top of the fixing frame extends along the radial direction, the grooves are used for fixing the permanent magnets, the permanent magnets with N polarity and S polarity are arranged in the cavity of the fixing frame in a staggered mode, each permanent magnet is provided with a base part and a part extending from the base part, the base part is arranged in the groove in the radial direction at the top of the fixing frame, and the part extending from the base part is arranged in the groove in the axial direction in the fixing frame. Utilize the utility model provides a revolve servo motor's light in weight, it is energy-conserving.

Description

Servo motor and electric automobile

Technical Field

the utility model relates to a be used for servo motor and electric automobile belongs to motor technical field.

Background

With the reduction of petroleum resources and the pollution of fuel automobiles to the environment, electric automobiles become the mainstream in the future. In an electric vehicle, the most important components influencing the quality are a battery, a motor and a motor controller, the motor is a key component for converting electric energy into mechanical energy, belongs to a core power component of the electric vehicle, and the electric vehicle is required to continuously and reliably run. In the prior art, a rotor of a motor is usually arranged in a stator, and an output shaft of the motor drives an execution component to operate through a speed reducer. The speed reducer is a very complicated gear transmission mechanism and is heavy, so that how to reduce the weight of the speed changer or not using the speed reducer is very important for reducing the weight of the electric vehicle.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects in the prior art, the invention aims to provide a servo motor and an electric automobile which are light in weight.

To achieve the object, a servo motor includes a stator and a rotor disposed at an outer periphery of the stator, the stator core has a plurality of pole pieces protruding outward in a radial direction of the stator and arranged at equal intervals in a circumferential direction, a plurality of first armature windings and a plurality of second armature windings wound on the pole pieces, it is characterized in that the rotor comprises a cylindrical permanent magnet fixing frame and a driving cylinder provided with teeth along the circumferential direction, a plurality of grooves which are arranged at equal intervals are arranged on the fixing frame, the parts of the grooves in the fixing frame extend along the axial direction and have fan-shaped sections, the part at the top of the fixing frame extends along the radial direction, the grooves are used for fixing the permanent magnets, the permanent magnets with N polarity and S polarity are arranged in the cavity of the fixing frame in a staggered mode, each permanent magnet is provided with a base part and a part extending from the base part, the base part is arranged in the groove in the radial direction at the top of the fixing frame, and the part extending from the base part is arranged in the groove in the axial direction in the fixing frame.

preferably, the servo motor further comprises a driving device, the driving device comprises an inverter circuit, the inverter circuit comprises a plurality of bridge arms and an energy storage capacitor, each bridge arm is provided with a booster circuit, each bridge arm at least comprises an upper first type electric switch and a lower first type electric switch, and a first end of the energy storage capacitor is connected to the anode of the first diode; the negative electrode of the first diode is connected with the first end of the upper first type electric switch; the second end of the upper first type of electrical switch is connected to the first end of the lower first type of electrical switch; the second end of the lower first type electric switch is connected with the second end of the energy storage capacitor and is connected with the ground; the control ends of the upper first type electric switch and the lower first type electric switch are connected to the control unit, the control unit provides pulse width modulation signals respectively, the booster circuit boosts the direct-current power supply and charges the energy storage capacitor, and the energy storage capacitor is used for providing electric energy for the electric switches of the bridge arm.

Preferably, the boost circuit comprises a second type of electrical switch, a first diode, a second diode, a third diode and a first capacitor; the control end of the second type electric switch is connected with the control end of the first type electric switch, the first end of the second type electric switch is connected with the anode of the first diode and the direct-current power supply, the second end of the second type electric switch is connected with the second end of the first capacitor, and the first end of the first capacitor is connected with the cathode of the first diode and the anode of the second diode; the cathode of the second diode is connected to the first end of the energy storage capacitor; the cathode of the third diode is connected to the source of the upper first type of electrical switch.

Preferably, there are three arms.

Preferably, the first type of electric switch is a field effect transistor, and the second type of electric switch is a field effect transistor with polarity opposite to that of the first type of field effect transistor.

Preferably, the first type of electrical switch is an N-channel fet and the second type of electrical switch is a P-channel fet.

Preferably, the drive apparatus includes at least an identification unit that calculates a sum J of the inertia of the rotor of the electric motor and the inertia of a rigid body load mounted on the electric motor and a viscous friction coefficient D from an input speed signal and a torque command and from the speed signal and the torque command.

preferably, the drive device further includes a control signal generation unit that generates the correction signal Ff according to the identification unit and the position instruction value.

Preferably, the correction signal is obtained by:

Ff＝AJP″+BDP′

Wherein A and B are constants, and P' ref is the 2 nd order differential of the position command value; p' ref is the 1 st order differential of the position reference value.

for realizing the utility model aims at providing an electric automobile is still provided to the utility model, it has arbitrary servo motor of the aforesaid.

Compared with the prior art, utilize the utility model provides a be used for servo motor and electric automobile, light in weight is energy-conserving.

Drawings

Fig. 1 is a schematic structural diagram of a servo motor provided by the present invention;

Fig. 2 is a schematic cross-sectional view of the servo motor shown in fig. 1, taken along line AB perpendicular to the shaft;

Fig. 3 is a block diagram of a driving device of a servo motor provided by the present invention;

Fig. 4 is a circuit diagram of an inverter circuit according to the present invention.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it is noted that the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

in the description of the present invention, it should be noted that, unless otherwise explicitly stated or limited, the terms "connected" and "connecting" should be interpreted broadly, and for example, they may be fixedly connected, detachably connected, or integrally connected, directly connected, indirectly connected through an intermediate medium, or connected between two elements, and those skilled in the art can understand the specific meaning of the above terms in the present invention according to specific situations.

Fig. 1 is a schematic structural diagram of a servo motor provided by the present invention; fig. 2 is a schematic cross-sectional view of the servo motor shown in fig. 1, which is cut perpendicular to the shaft along the line AB of the servo motor, as shown in fig. 1-2, the servo motor includes a stator and a rotor disposed at the periphery of the stator, the stator core 7 has a plurality of pole shoes 2 protruding outward in the radial direction of the stator and arranged at equal intervals along the circumferential direction, and the plurality of first armature windings 4 and the plurality of second armature windings 5 are wound on the plurality of pole shoes 2. In the present invention, the phase and polarity of the first armature winding 4 and the plurality of second armature windings 5 wound around each pole piece 2 are (U +/U +) (U-/V +) (V-/V-) (W +/V +) (W +/W +) (W +/U +) (U-/U-) (U +/V-) (V +/V +) (W +/V-) (W +/W-) (W +/U-), in the clockwise direction from the upper end of the paper surface, and here, the phase wound around one pole piece is represented by "/", and "+" and "-" represent the winding polarities (winding directions) opposite to each other. However, regardless of the order of the 2 windings wound on the same pole piece, the position indicated as (U +/V-) may be set to (V-/V +) so that the radial positions are reversed, for example.

The rotor comprises a cylindrical permanent magnet fixing frame and a driving cylinder 4 provided with teeth along the circumferential direction, a plurality of grooves which are arranged at equal intervals are arranged on the fixing frame, the parts of the grooves in the fixing frame extend along the axial direction, the cross sections of the grooves are fan-shaped, the parts of the grooves at the top of the fixing frame extend along the radial direction, the grooves are used for fixing the permanent magnets, permanent magnets with N polarity and S polarity are arranged in the cavity of the fixing frame in a staggered mode, each permanent magnet is L-shaped and provided with a base part and a part extending from the base part, the base part is arranged in the radial groove at the top of the fixing frame, and the part extending from the base part is arranged.

Utilize the utility model discloses servo motor of structure does not need the reduction gear, but the work of direct drive operational unit, has consequently reduced weight, simultaneously, utilizes the low-order magnetomotive force composition that the magnetomotive force can be weakened to the mode of above-mentioned winding armature winding to do not have the change of low-order magnetic flux in the iron core, do not take place eddy current. Since the eddy current flowing through the rotor core can be reduced, the eddy current loss can be reduced. Since eddy current can be fundamentally reduced, a conventional laminated field pole yoke or divided block yoke is not required, and the cost for equipment or the cost for an increase in the number of parts can be reduced. Utilize the utility model provides a servo motor's equipment is small, and the activity is nimble.

Fig. 3 is a block diagram of a driving apparatus of a servo motor according to the present invention, as shown in fig. 3, the driving apparatus of the present invention includes a position control unit 31, a speed control unit 32, a torque control unit 33, a position detection unit 28, a differentiator 35 and a control constant identification unit 36, wherein the position control unit 31 inputs a position command Pref and a position signal Pfb of the motor M, and outputs a speed command Vref to the speed control unit 32. The speed control means 32 receives the speed command Vref and the speed signal Vfb of the motor M, and outputs a torque command Tref to the torque control means 33 and the control constant recognition means 36. The torque control unit 33 receives the torque command Tref, and outputs the motor M and the drive current Im1 to the motor M. The motor M is driven by the motor driving current Im1 to generate a torque to drive the rigid body load. In addition, a position detector 28 is mounted in the motor M to output a motor position signal Pfb to the position control device unit 31 and the differentiator 35. The differentiator 35 receives the position signal Pfb and outputs the speed signal Vfb to the speed control unit 32 and the control constant identifying unit 36. Control constant identification section 36 inputs speed signal Vfb and torque command Tref, and calculates the sum J of the inertia of the rotor of motor M and the inertia of the rigid body load mounted on motor M and viscous friction coefficient D from speed signal Vfb and torque command Tref. The position control unit 31 performs a position control operation to match the position signal Pfb with the position command Pref. The speed control unit 32 performs a speed control operation to make the speed signal Vfb coincide with the speed command Vref. The torque control means 33 performs a torque control operation so that the torque generated by the electric motor M matches the torque command Tref. The position detection unit 28 detects the position of the motor M. The differentiator 35 obtains a difference at regular intervals between the position signals Pfb to obtain the velocity signal Vfb.

The utility model provides a motor drive circuit still includes signal generator 37, and its input position control unit's position instruction Pref generates output behind the correction signal Ff. The sum of the output signal of the speed control unit 32 and the correction signal Ff is a torque command Tref. The utility model discloses a preceding correction signal Ff obtains through the following formula:

Ff＝AJP″+BDP′

Where A and B are constants and P' ref is the 2 nd order differential of the position command Pref; p' ref is the 1 st order differential of the position command Pref. The control constant recognition unit 36 calculates the sum J of the inertia and the viscous friction coefficient D to control J and D in the above equation to further control the motor M.

In the utility model, the water-saving device is provided with a water-saving valve,

Fig. 4 is a circuit diagram of an inverter circuit, as shown in fig. 4, the present invention provides an inverter circuit for converting dc voltage into ac voltage and providing three U-phase, V-phase and W-phase armature windings of a motor M respectively. The inverter circuit comprises a plurality of bridge arms, a capacitor C4, a capacitor C5 and an inductor L, and is used for converting the direct-current voltage output by the direct-current power supply Ec into alternating-current voltage. Each bridge arm is provided with a booster circuit, each bridge arm at least comprises an upper first type electric switch and a lower first type electric switch, and the first end of the energy storage capacitor C4 is connected to the anode of the first diode; the negative electrode of the first diode is connected with the upper first type electric switch; the second end of the upper first type of electrical switch is connected to the first end of the lower first type of electrical switch; the second end of the lower first type electric switch is connected with the second end of the energy storage capacitor and is connected with the ground; the control ends of the upper first type electric switch and the lower first type electric switch are connected to the control unit, the control unit provides pulse width modulation signals respectively, the booster circuit boosts the direct-current power supply and charges the energy storage capacitor, and the energy storage capacitor supplies electric energy to the one-phase armature winding through the bridge arm. Preferably, the boost circuit comprises a second type of electrical switch, a second diode, a first third diode and a first capacitor; the control end of the second type electric switch is connected with the first type electric switch, the first end of the second type electric switch is connected with the anode of the first diode and the current power supply, the second end of the second type electric switch is connected with the second end of the first capacitor, and the first end of the first capacitor is connected with the cathode of the first diode and the anode of the second diode; the cathode of the second diode is connected to the first end of the energy storage capacitor; the cathode of the third diode is connected to the source of the upper first type of electrical switch. Preferably, there are three arms. Preferably, the first type of electric switch is a field effect transistor, and the second type of electric switch is a field effect transistor with polarity opposite to that of the first type of field effect transistor. More preferably, the first type of electrical switch is an N-channel fet and the second type of electrical switch is a P-channel fet.

Specifically, the utility model provides an inverter circuit includes three bridge arm, electric capacity C4, electric capacity C5 and inductance L, and first bridge arm includes N channel field effect transistor Q1 and lower N channel field effect transistor Q2, the first end of energy storage electric capacity C4 is connected to node diode D7's positive pole, node N7 promptly; the cathode of the diode D7 is connected to the drain of the upper N-channel FET Q1, i.e., the node N8; the source electrode of the upper N-channel field effect transistor Q1 is connected with the drain electrode of the lower N-channel field effect transistor Q2 and connected with the U phase of the motor M; the source of the lower N-channel FET Q2 is connected to the second terminal of the storage capacitor C4 and to ground, i.e., node N9; the gates of the upper N-channel field effect transistor Q1 and the lower N-channel field effect transistor Q2 are both connected to the control unit, the control unit respectively provides pulse width modulation signals (PWM), the booster circuit boosts the direct-current power supply Ec and charges the energy storage capacitor C4, and the energy storage capacitor C4 is used for providing electric energy for the U-phase armature winding through a bridge arm. The positive terminal of the dc power supply Ec is connected to the first terminal of the inductor L, and the second terminal of the inductor L is connected to the node N10. The boosting circuit comprises a P-channel field effect transistor Q7, a diode D4, a diode D8, a diode D1 and a capacitor C1; the grid electrode of the P-channel field effect Q7 tube is connected with the grid electrode of the upper N-channel field effect Q1, the drain electrode of the P-channel field effect Q7 is connected with a node N10, and the source electrode of the P-channel field effect Q7 is connected with the second end of the capacitor C1 and the anode of the diode D1, namely a node N2; a first end of the capacitor C1 is connected to the cathode of the diode D4 and the anode of the diode D8, i.e., the node N1; the cathode of the diode D8 is connected to the first terminal of the energy storage capacitor C4, and the second terminal of the capacitor C4 is grounded, i.e., the node N9; the cathode of the diode D1 is connected to the source of the upper N-channel fet Q1.

The working process is as follows: the control unit provides PWM signals with opposite phases for an upper N-channel field effect transistor Q1 and a lower N-channel field effect transistor Q2, when the grid of the lower N-channel field effect transistor Q2 of the bridge arm is at a high potential and the grid of the upper N-channel field effect transistor Q1 is at a low potential, the lower N-channel field effect transistor Q2 is conducted, the upper N-channel field effect transistor Q1 is cut off, the P-channel field effect transistor Q7 is conducted, a diode D1 is conducted, diodes D4 and D8 are cut off, and a direct-current power supply Ec charges an inductor L; when the grid of the lower N-channel field effect transistor Q2 of the bridge arm is at a low potential, and the grid of the upper N-channel field effect transistor Q1 is at a high potential, the lower N-channel field effect transistor Q2 is turned off, the upper N-channel field effect transistor Q1 is turned on, the P-channel field effect transistor Q7 is turned off, the diode D1 and the diode D4 start to be turned on first, the diode D8 is turned off, the dc power supply Ec and the inductor L charge the capacitor C1 and the capacitor C5, when the sum of the voltages of the capacitors C1 and C5 is higher than the voltage of the capacitor C4, the diode D4 is turned off, the diode D8 is turned on, and the capacitor C1 charges the capacitor C4, so that the voltage of the capacitor C4 is higher than the dc power. The capacitor C4 is rectified by the diode D7 and then converted into ac by the bridge arm to supply power to the U phase of the motor.

The second bridge arm comprises an upper N-channel field effect transistor Q3 and a lower N-channel field effect transistor Q4, wherein the source electrode of the upper N-channel field effect transistor Q3 is connected with the drain electrode of the lower N-channel field effect transistor Q4 and is connected with the V phase of the motor M; the source of the lower N-channel FET Q4 is connected to the second terminal of the storage capacitor C4 and to ground, i.e., node N9; the gates of the upper N-channel field effect transistor Q3 and the lower N-channel field effect transistor Q4 are both connected to the control unit, the control unit respectively provides pulse width modulation signals (PWM), the booster circuit boosts the direct-current power supply Ec and charges the energy storage capacitor C4, and the energy storage capacitor C4 provides electric energy for the U-phase armature winding through a bridge arm. The boosting circuit comprises a P-channel field effect transistor Q8, a diode D5, a diode D9, a diode D2 and a capacitor C2; the grid electrode of the P-channel field effect Q8 tube is connected with the grid electrode of the upper N-channel field effect Q3, the drain electrode of the P-channel field effect Q8 is connected with a node N10, and the source electrode of the P-channel field effect Q8 is connected with the second end of the capacitor C2 and the anode of the diode D2, namely a node N4; a first end of the capacitor C2 is connected to the cathode of the diode D5 and the anode of the diode D9, i.e., the node N3; the cathode of the diode D9 is connected to the first terminal of the energy storage capacitor C4, and the second terminal of the capacitor C4 is grounded, i.e., the node N9; the cathode of the diode D2 is connected to the source of the upper N-channel fet Q3.

The working process is as follows: the control unit provides PWM signals with opposite phases for an upper N-channel field effect transistor Q3 and a lower N-channel field effect transistor Q4, when the grid of the lower N-channel field effect transistor Q4 of the bridge arm is at a high potential and the grid of the upper N-channel field effect transistor Q3 is at a low potential, the lower N-channel field effect transistor Q4 is conducted, the upper N-channel field effect transistor Q3 is cut off, the P-channel field effect transistor Q8 is conducted, a diode D2 is conducted, diodes D5 and D9 are cut off, and a direct-current power supply Ec charges an inductor L; when the grid of the lower N-channel field effect transistor Q4 of the bridge arm is at a low potential, the grid of the upper N-channel field effect transistor Q3 is at a high potential, the lower N-channel field effect transistor Q4 is cut off, the upper N-channel field effect transistor Q3 is turned on, the P-channel field effect transistor Q8 is cut off, the diode D2 and the diode D5 are turned on, the diode D9 is cut off, the direct-current power supply Ec and the inductor L charge the capacitor C2 and the capacitor C5, when the sum of the voltages of the capacitor C2 and the capacitor C5 is higher than the voltage of the capacitor C4, the diode D5 is cut off, the diode D9 is turned on, and the capacitor C2 charges the capacitor C4, so that the voltage of the capacitor C4 is higher than the direct. The capacitor C4 is rectified by the diode D7, and then the rectified current is converted into alternating current by the bridge arm and provides electric energy for the V phase of the motor.

The third bridge arm comprises an upper N-channel field effect transistor Q5 and a lower N-channel field effect transistor Q6, wherein the source electrode of the upper N-channel field effect transistor Q6 is connected with the drain electrode of the lower N-channel field effect transistor Q6 and is connected with the W phase of the motor M; the source of the lower N-channel FET Q6 is connected to the second terminal of the storage capacitor C4 and to ground, i.e., node N9; the gates of the upper N-channel field effect transistor Q5 and the lower N-channel field effect transistor Q6 are both connected to the control unit, the control unit respectively provides pulse width modulation signals (PWM), the booster circuit boosts the direct-current power supply Ec and charges the energy storage capacitor C4, and the energy storage capacitor C4 is used for providing electric energy for the U-phase armature winding through a bridge arm. The boosting circuit comprises a P-channel field effect transistor Q9, a diode D6, a diode D10, a diode D3 and a capacitor C3; the grid electrode of the P-channel field effect Q9 tube is connected with the grid electrode of the upper N-channel field effect Q5, the drain electrode of the P-channel field effect Q9 is connected with a node N10, and the source electrode of the P-channel field effect Q9 is connected with the second end of the capacitor C3 and the anode of the diode D3, namely a node N6; a first end of the capacitor C3 is connected to the cathode of the diode D6 and the anode of the diode D10, i.e., the node N5; the cathode of the diode D10 is connected to the first terminal of the energy storage capacitor C4, and the second terminal of the capacitor C4 is grounded, i.e., the node N9; the cathode of the diode D3 is connected to the source of the upper N-channel fet Q5.

The working process is as follows: the control unit provides PWM signals with opposite phases for an upper N-channel field effect transistor Q5 and a lower N-channel field effect transistor Q6, when the grid of the lower N-channel field effect transistor Q6 of the bridge arm is at a high potential and the grid of the upper N-channel field effect transistor Q5 is at a low potential, the lower N-channel field effect transistor Q6 is conducted, the upper N-channel field effect transistor Q5 is cut off, the P-channel field effect transistor Q9 is conducted, a diode D3 is conducted, diodes D6 and D10 are cut off, and a direct-current power supply Ec charges an inductor L; when the grid of the lower N-channel field effect transistor Q6 of the bridge arm is at a low potential, the grid of the upper N-channel field effect transistor Q5 is at a high potential, the lower N-channel field effect transistor Q6 is cut off, the upper N-channel field effect transistor Q5 is turned on, the P-channel field effect transistor Q9 is cut off, the diode D3 and the diode D6 are turned on, the diode D10 is cut off, the direct-current power supply Ec and the inductor L charge the capacitor C3 and the capacitor C5, when the sum of the voltages of the capacitor C3 and the capacitor C5 is higher than the voltage of the capacitor C4, the diode D6 is cut off, the diode D10 is turned on, and the capacitor C3 charges the capacitor C4, so that the voltage of the capacitor C4 is higher than the direct. The capacitor C4 is rectified by the diode D7, and then the rectified current is converted into alternating current by the bridge arm and provides electric energy for the W phase of the motor.

The present invention has been described with reference to a three-phase inverter, and is not limited to three phases, and may be any phase greater than or equal to 2. The utility model discloses boost DC power supply earlier and save in storage capacitor C4. The capacitor C4 is rectified by the diode D7 and then converted into alternating current by the bridge arm and supplied to the motor, so that the cost is saved and the weight is reduced.

According to the utility model discloses, the control unit includes at least equipment includes Central Processing Unit (CPU), Read Only Memory (ROM), Random Access Memory (RAM), host bus, interface, input unit, output unit, memory cell, driver, connection port and communication unit. The CPU functions as an arithmetic processing unit and a control unit, i.e., a processor. The CPU controls the operating state of the servo motor wholly or partially according to various programs stored in the ROM, the RAM, the memory sheet, or the removable recording medium. The ROM stores programs and operation parameters used by the CPU. The RAM temporarily stores programs for the CPU100 and parameters that vary according to the execution of the programs. The CPU, ROM, RAM, and interface are connected to each other via a host bus including an internal bus such as a CPU bus.

the input unit exemplarily includes a mouse, a keyboard, a touch panel, buttons, switches, and a lever operated by a user, but is not limited thereto. In addition, the input unit may be a remote control using infrared light or radio waves. Alternatively, the input unit may be an external connection device or a client device, which may perform the operation of the servo motor. The input unit includes an input control circuit that generates an input signal based on information input by a user through the above-described operation section and outputs the generated input signal to the CPU. Through the operation input, a user of the servo motor can input various data to the servo motor and instruct the servo motor to perform various operations.

The output unit illustratively includes a display unit including, for example, a Liquid Crystal Display (LCD) unit, an Electroluminescence (EL) display unit, and the like, and a printer, and the like. The storage unit may be a magnetic storage device such as a Hard Disk Drive (HDD), a semiconductor storage device, an optical storage device, or a magneto-optical storage device. The storage unit stores programs executed by the CPU, various data, and the like.

The drive acts as a reader/writer for the storage medium. The driver is incorporated into the servo motor or externally connected to the servo motor. The drive reads out data on a removable recording medium such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, and outputs the read-out data to the RAM. In addition, the drive can write data on the removable recording medium. Examples of the removable recording medium include a DVD medium, a CD medium, and a Secure Digital (SD) memory card. Alternatively, the removable recording medium may be an Integrated Circuit (IC) card or an electronic device including a contactless IC chip.

The connection port is a port for directly connecting an external connection device to the servo motor. Examples of connection ports include a Universal Serial Bus (USB) interface, a Small Computer System Interface (SCSI) port, an RS-232C port, an optical audio terminal, and the like. When the external connection device is connected to the connection port, the servo motor may directly acquire data from the external connection device and supply the data to the external connection device.

The communication unit is a wireless communication unit for communicating the servo motor with the server and/or the client terminal.

The utility model also provides an electric automobile, it utilizes the utility model provides a servo motor is with drive mechanical execution part.

The invention has been described in detail with reference to the drawings, but the description is only intended to be construed in an illustrative manner. The scope of the invention is not limited by the description. Any changes or substitutions that can be easily made by those skilled in the art within the technical scope of the present invention are intended to be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (7)

1. A servo motor includes a stator and a rotor disposed at an outer circumference of the stator, a core of the stator having a plurality of pole pieces protruding outward in a radial direction of the stator and arranged at equal intervals in a circumferential direction, a plurality of first armature windings and a plurality of second armature windings wound on the pole pieces, it is characterized in that the rotor comprises a cylindrical permanent magnet fixing frame and a driving cylinder provided with teeth along the circumferential direction, a plurality of grooves which are arranged at equal intervals are arranged on the fixing frame, the parts of the grooves in the fixing frame extend along the axial direction and have fan-shaped sections, the part at the top of the fixing frame extends along the radial direction, the grooves are used for fixing the permanent magnets, the permanent magnets with N polarity and S polarity are arranged in the cavity of the fixing frame in a staggered mode, each permanent magnet is provided with a base part and a part extending from the base part, the base part is arranged in the groove in the radial direction at the top of the fixing frame, and the part extending from the base part is arranged in the groove in the axial direction in the fixing frame.

2. The servo motor according to claim 1, further comprising a driving device, wherein the driving device comprises an inverter circuit, the inverter circuit comprises a plurality of bridge arms and an energy storage capacitor, a booster circuit is arranged on each bridge arm, each bridge arm comprises at least an upper first type electric switch and a lower first type electric switch, and a first end of the energy storage capacitor is connected to an anode of the first diode; the negative electrode of the first diode is connected with the first end of the upper first type electric switch; the second end of the upper first type of electrical switch is connected to the first end of the lower first type of electrical switch; the second end of the lower first type electric switch is connected with the second end of the energy storage capacitor and is connected with the ground; the control ends of the upper first type electric switch and the lower first type electric switch are connected to the control unit, the control unit provides pulse width modulation signals respectively, the booster circuit boosts the direct-current power supply and charges the energy storage capacitor, and the energy storage capacitor is used for providing electric energy for the electric switches of the bridge arm.

3. The servo motor of claim 2, wherein the boost circuit comprises a second type of electrical switch, a first diode, a second diode, a third diode, and a first capacitor; the control end of the second type electric switch is connected with the control end of the first type electric switch, the first end of the second type electric switch is connected with the anode of the first diode and the direct-current power supply, the second end of the second type electric switch is connected with the second end of the first capacitor, and the first end of the first capacitor is connected with the cathode of the first diode and the anode of the second diode; the cathode of the second diode is connected to the first end of the energy storage capacitor; the cathode of the third diode is connected to the source of the upper first type of electrical switch.

4. The servo motor of claim 3 wherein there are three bridge arms.

5. A servo motor according to any of claims 2-4, wherein the first type of electrical switch is a FET and the second type of electrical switch is a FET of opposite polarity to the first type of FET.

6. The servo motor of claim 5, wherein the first type of electrical switch is an N-channel FET and the second type of electrical switch is a P-channel FET.

7. An electric vehicle comprising the servo motor according to any one of claims 1 to 6.