Winding multi-sector adjustable limited angle torque motor

Abstract

The invention provides a winding multi-sector adjustable limited angle torque motor, and belongs to the technical field of motors, the winding multi-sector adjustable limited angle torque motor comprises a rotor assembly, a stator assembly and a power supply assembly, the stator assembly is arranged on the outer side of the rotor assembly, the power supply assembly is connected with the stator assembly, and the rotor assembly comprises a rotor core, a U-shaped built-in permanent magnet and a rotating shaft. The rotor core is arranged on the outer side of the rotating shaft, the U-shaped built-in permanent magnet is embedded in the rotor core, the stator assembly comprises a stator core and a multi-sector parallel annular stator winding, and the stator core sleeves the outer side of the rotor core. The winding adopts a multi-sector parallel connection mode, and other sectors can still work normally under the condition that part of sectors have faults, so that the motor has certain fault tolerance capability.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to an adjustable limited-angle torque motor with multiple winding sectors. Background Art

[0002] The structure of a limited angle torque motor is similar to that of a brushless DC motor, except that it is not a continuous rotation mechanism. This type of motor does not rely on an intermediate transmission structure and can output a constant large torque within a certain rotation angle. It has the characteristics of high torque density, small output torque fluctuation, simple structure, and easy control. Therefore, limited angle torque motors are often used as direct drive mechanisms and are widely used in the field of repeated deflection actuators such as servo valves, satellite remote sensing imaging, and high-voltage circuit breakers.

[0003] With the continuous development of the field of reciprocating yaw actuators, traditional limited-angle torque motors are required to shorten the constant torque range under a certain power to increase the output torque to meet the needs of heavy-load conditions; and to reduce the output torque to widen the constant torque range to meet the needs of wide-range conditions. However, the existing traditional solutions cannot simply and quickly adjust the two key performance indicators of limited-angle torque motors: constant torque range and constant torque, and it is difficult to meet the needs of complex and changing working conditions.

[0004] In order to enable the limited-angle torque motor to have the ability to flexibly adjust the constant torque range and constant torque, while improving its fault tolerance and avoiding the negative effects of structural redundancy and complex adjustment strategies, it is necessary to propose an adjustable limited-angle torque motor with multi-sector windings to meet the needs of multiple working conditions. Summary of the invention

[0005] The purpose of the present invention is to provide an adjustable limited-angle torque motor with multiple winding sectors to solve the technical problems mentioned in the background technology. Under the condition of constant power, the width of the constant torque interval and the constant torque amplitude can be flexibly adjusted, so that a single machine can meet the requirements of multiple working conditions in actual industrial practice applications.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A winding multi-sector adjustable limited angular torque motor comprises a rotor assembly, a stator assembly and a power supply assembly, wherein the stator assembly is arranged on the outside of the rotor assembly, the power supply assembly is connected to the stator assembly, the rotor assembly comprises a rotor core, a U-shaped built-in permanent magnet and a rotating shaft, the rotor core is arranged on the outside of the rotating shaft, the U-shaped built-in permanent magnet is embedded in the rotor core, the stator assembly comprises a stator core and a multi-sector parallel annular stator winding, and the stator core is sleeved on the outside of the rotor core.

[0008] Furthermore, the stator annular winding is divided into a plurality of sectors, all of which are wound around the stator core, and a group of lead wires are led out of the annular winding of each sector.

[0009] Furthermore, the power supply assembly includes a DC power supply and a switch, the lead wire of the stator annular winding is connected to the DC power supply via the switch, and the power on and off of each sector winding is controlled by the switch.

[0010] Furthermore, the stator winding is divided into four poles, and the winding span of each pole is θ s Each pole winding is divided into N sectors, each sector has a lead wire connected to the power supply through a switch, and the connection method is parallel, where θ s The value does not exceed 90°, N is an integer, and the value does not exceed 8.

[0011] Furthermore, the span of each sector winding is θ i， The sum of the spans of the N sector windings is equal to θ s , where i=1~N.

[0012] Furthermore, the rotor magnetic poles of the rotor assembly are divided into four poles, and the magnetic pole angle of each pole is θ PM , the magnetization directions of adjacent poles are opposite, and the magnetization directions of non-adjacent poles are the same, θ PM The value does not exceed θ s .

[0013] Furthermore, the width of the constant torque interval CTR of the torque motor is the winding span per pole minus the magnetic pole angle per pole, that is, CTR = θ s -θ PM .

[0014] Furthermore, the function of the switch is to connect the sector winding lead wire and the power supply, and the number of the switch is N, which is consistent with the number of sectors of the unipolar winding.

[0015] Furthermore, as the number of closed switches increases, the output torque of the motor decreases and the constant torque range widens; as the number of closed switches decreases, the output torque of the motor increases and the constant torque range decreases.

[0016] The rotor core is set on the rotating shaft, and the U-shaped built-in permanent magnet is embedded in the rotor core; the stator core is sleeved on the outside of the rotor core; the multi-sector parallel annular winding surrounds the stator core, and the lead wire is connected to the DC power supply through a switch. 1) The overall structure is simple and efficient, and the torque can be directly output without redundant transmission structure. 2) The winding is set in a multi-sector parallel form. In the event of a failure in the winding of some sectors, the other sectors can still work normally. 3) The constant torque interval width can be changed through different power-on strategies.

[0017] The present invention has the following beneficial effects due to the adoption of the above technical solution:

[0018] (1) The winding of the present invention adopts a multi-sector parallel connection form. When a part of the sectors fails, the other sectors can still work normally, so that the motor has a certain fault tolerance capability.

[0019] (2) The present invention can adjust two key performance indicators of the motor: constant torque range and constant torque through different power-on strategies, so that the motor can handle a variety of working conditions.

[0020] (3) The present invention can realize the change of the power-on strategy by using a simple mechanical switch structure, and the control method is simple and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of a two-dimensional cross-sectional structure of a motor provided by an embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the magnetization direction and magnetic circuit of the magnetic steel provided in an embodiment of the present invention;

[0023] Figure 3 Schematic diagram of the motor winding form provided by an embodiment of the present invention;

[0024] Figure 4 It is a schematic diagram of a connection method between a quarter winding and a power supply provided by an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of the equivalent form of windings under the power-on strategy 010 provided in an embodiment of the present invention;

[0026] Figure 6 It is a schematic diagram of an equivalent form of a winding under a power-on strategy 110 provided in an embodiment of the present invention;

[0027] Figure 7 It is a schematic diagram of the variation of the motor output torque with the rotation angle under different power-on strategies provided by an embodiment of the present invention.

[0028] Figure numerals, 1-rotating shaft; 2-rotor core; 3-built-in U-shaped permanent magnet; 4-statator winding; 5-stator core; 6-switch K1; 7-switch K2; 8-switch K3; 9-winding lead wire; 10-DC power supply; 11-positive node of DC power supply; 12-negative node of DC power supply. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are only for the purpose of enabling the reader to have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be implemented even without these specific details.

[0030] like Figure 1-Figure 4 As shown, a winding multi-sector adjustable limited angle torque motor includes a rotor assembly, a stator assembly and a power supply assembly; wherein the rotor assembly is composed of a rotor core, a U-shaped internal permanent magnet and a rotating shaft. The rotor core is arranged on the rotating shaft and is axially penetrated with a U-shaped magnetic steel slot; the U-shaped internal permanent magnet is embedded in the stator core and is divided into four poles, each pole is composed of three rectangular permanent magnets to form a U-shaped structure; the magnetic pole angle θ of the U-shaped structure PM =20°; the rotor assembly directly outputs torque through the shaft.

[0031] The stator assembly consists of a stator core and a multi-sector parallel annular winding. The stator core is sleeved on the outside of the rotor core; the multi-sector parallel annular winding is divided into four poles, and each pole winding is divided into three sectors, named sector one, sector two and sector three respectively; each sector winding leads out a set of lead wires, which are connected to the DC power supply through a switch; the span of each pole winding is θ s =80°; sector one winding span θ1 = 20°; sector two winding span θ2 = 40°; sector three winding span θ3 = 20°.

[0032] The material of the stator and rotor core is silicon steel sheet DW540_50, the permanent magnet material is rare earth material NdFeB, and the material of the shaft is 20 # Steel, winding material is enameled copper.

[0033] The power supply assembly consists of a DC power supply and a switch. The DC power supply has two output interfaces, which are positive and negative. One end of the switch is connected to the positive pole of the DC power supply, and the other end is connected to one end of the sector winding lead wire. There are three switches, named K1, K2 and K3. For auxiliary explanation, the closed switch is represented by K i =1, the switch is disconnected as K i =0. When K i =1, the winding of sector i is energized; when K i = 0, the winding of sector i is not energized. If K1 = 0, K2 = 0, K3 = 1, it means that the windings of sectors one and two are not energized, and the winding of sector three is energized.

[0034] In order to reduce costs and improve motor reliability, the switch is selected as a common mechanical structure, and the power supply is a DC power supply with adjustable voltage and current. It should be emphasized that for automation control scenarios, a trigger circuit + power electronic switch device + rectifier circuit can be used to achieve digital adjustment of the power-on strategy. The selection of common mechanical switches and DC power supplies is only to simplify the description process.

[0035] According to the closing / opening status of the three switches, the power-on strategies can be divided into (K1, K2, K3) = 000, 001, 010, 011, 100, 101, 110 and 111; among them, the power-on strategy 000 is the motor no-load condition, the power-on strategies 001, 100, 101 are the motor single-angle output peak torque conditions, and the other power-on strategies are the motor rated working conditions.

[0036] The working principle is described as follows:

[0037] After magnetization, the permanent magnet forms an excitation magnetic field, and the magnetic lines of force form a closed loop through the permanent magnet N pole-rotor core-air gap-stator core-air gap-rotor core-permanent magnet S pole. After the winding in the air gap is energized with current, the conductor on the radial inner side of the stator core is acted upon by the electromagnetic force, driving the stator core to rotate. Since the stator core is fixed, the rotor rotates under the reaction force and outputs torque through the shaft.

[0038] Because the magnetic pole angle of the permanent magnet is smaller than the winding span, when operating within the span of the unipolar winding, the number of coil turns and coil polarity coupled to the magnetic pole remain unchanged, so the torque amplitude and direction of the motor output remain unchanged, and this torque is called constant torque. When operating outside the span of the unipolar winding, the number of coil turns and coil polarity coupled to the magnetic pole change, and the torque output by the motor is no longer constant. Therefore, the limited angle torque motor can only output constant torque within a certain angle range, and this angle range is called the constant torque range. The constant torque range is related to the unipolar winding span and the magnetic pole angle.

[0039] When the number of closed switches increases, the number of energized sector windings also increases, so the span of the unipolar winding also increases. Under the condition of a constant magnetic pole angle, the width of the constant torque interval will also increase; the increase in the number of energized sector windings will also increase the total resistance of the windings. Under the condition of a constant power supply, the winding current will decrease, so the constant torque output by the motor will decrease. That is, as the number of closed switches increases, the constant torque interval widens and the constant torque decreases; in other words, as the number of closed switches decreases, the constant torque interval shrinks and the constant torque increases.

[0040] Figure 2 Schematic diagram of magnetizing direction and magnetic circuit of magnetic steel provided by an embodiment of the present invention; magnetizing directions of any adjacent magnetic poles are opposite, and magnetizing directions of any non-adjacent magnetic poles are the same. Closing directions of any adjacent magnetic circuits are opposite, and closing directions of any non-adjacent magnetic circuits are the same.

[0041] Figure 3 Schematic diagram of the motor winding provided by the embodiment of the present invention; the stator winding is divided into four poles, each pole winding is divided into three sectors, and each sector winding has a set of lead wires connected in parallel to the power supply. The winding directions of any adjacent pole windings are opposite, and the winding directions of any non-adjacent pole windings are the same.

[0042] Figure 4 The figure is a schematic diagram of the connection mode between a quarter winding and a power supply provided by an embodiment of the present invention; one end of the lead wire of each sector winding is connected to a switch, and the other end is connected to the negative pole of a DC power supply. The other end of the switch is connected to the positive pole of the DC power supply.

[0043] Figure 5 This is a schematic diagram of the equivalent form of windings under the power-on strategy 010 provided by an embodiment of the present invention; under this power-on strategy, only the sector 2 winding is energized, so it can be equivalent to a winding form in which the sector 1 and sector 3 windings do not exist. At this time, the span of the single-pole stator winding is θ2 = 40°, and the constant torque interval width CTR = θ2-θ PM =20°.

[0044] Figure 6 This is a schematic diagram of the equivalent form of windings under the power-on strategy 110 provided by an embodiment of the present invention; under this power-on strategy, only the windings of sectors 1 and 2 are powered, so it can be equivalent to a winding form in which the winding of sector 3 does not exist. At this time, the span of the single-pole stator winding is θ1+θ2=60°, and the constant torque interval width CTR=θ1+θ2-θ PM =40°.

[0045] Figure 7 It is a schematic diagram of the change of motor output torque with rotation angle under different power-on strategies provided by an embodiment of the present invention; the constant torque interval of power-on strategy 010 is the narrowest and the constant torque is the largest; the constant torque interval of power-on strategy 110 is wider and the constant torque is smaller; the constant torque interval of power-on strategy 111 is the widest and the constant torque is the smallest.

[0046] Matters not covered by the present invention are known technologies.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An adjustable limited angle torque motor with multiple winding sectors, characterized in that: It includes a rotor assembly, a stator assembly and a power supply assembly. The stator assembly is arranged on the outside of the rotor assembly. The power supply assembly is connected to the stator assembly. The rotor assembly includes a rotor core, a U-shaped built-in permanent magnet and a rotating shaft. The rotor core is arranged on the outside of the rotating shaft. The U-shaped built-in permanent magnet is embedded in the rotor core. The stator assembly includes a stator core and a multi-sector parallel annular stator winding. The stator core is sleeved on the outside of the rotor core.

2. The adjustable limited angle torque motor with multiple winding sectors according to claim 1, characterized in that: The stator annular winding is divided into a number of sectors, all of which are wrapped around the stator core, and the annular winding of each sector leads out a group of lead wires.

3. The adjustable limited angle torque motor with multiple winding sectors according to claim 1, characterized in that: The power supply assembly includes a DC power supply and a switch. The lead wire of the stator annular winding is connected to the DC power supply via the switch, and the switch controls the power on and off of each sector winding.

4. The adjustable limited angle torque motor with multiple winding sectors according to claim 1, characterized in that: The stator winding is divided into four poles, and the winding span of each pole is θ s Each pole winding is divided into N sectors, each sector has a lead wire connected to the power supply through a switch, and the connection method is parallel, where θ s The value does not exceed 90°, N is an integer, and the value does not exceed 8.

5. The adjustable limited angle torque motor with multiple winding sectors according to claim 4, characterized in that: The span of each sector winding is θ i， The sum of the spans of the N sector windings is equal to θ s , where i=1~N.

6. The adjustable limited angle torque motor with multiple winding sectors according to claim 1, characterized in that: The rotor magnetic poles of the rotor assembly are divided into four poles, and the magnetic pole angle of each pole is θ PM , the magnetization directions of adjacent poles are opposite, and the magnetization directions of non-adjacent poles are the same, θ PM The value does not exceed θ s .

7. The adjustable limited angle torque motor with multiple winding sectors according to claim 1, characterized in that: The width of the constant torque interval CTR of the torque motor is the winding span per pole minus the magnetic pole angle per pole, that is, CTR = θ s -θ PM .

8. The adjustable limited angle torque motor with multiple winding sectors according to claim 4, characterized in that: The function of the switch is to connect the sector winding lead wire and the power supply. The number of the switch is N, which is consistent with the number of sectors of the unipolar winding.

9. The adjustable limited angle torque motor with multiple winding sectors according to claim 7, characterized in that: As the number of closed switches increases, the output torque of the motor decreases and the constant torque range widens. As the number of closed switches decreases, the output torque of the motor increases and the constant torque range decreases.

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