Rotor series capacitor type asynchronous linear motor and rotor series capacitor type asynchronous rotating motor

Abstract

The invention relates to the technical field of asynchronous motors, and discloses a rotor series capacitor type asynchronous linear motor and a rotor series capacitor type asynchronous rotating motor. The asynchronous linear motor comprises a motor shell, a slip ring, an electric brush, a stator, a rotor and a capacitor, the slip ring, the electric brush, the stator, the rotor and the capacitor are arranged in the motor shell, the stator comprises a stator iron core and a stator winding, the rotor comprises a rotor iron core and a rotor winding, and each phase of the rotor winding is connected with the capacitor in series. Therefore, the power factor of the asynchronous linear motor can be effectively improved, the current and voltage required by the operation of the motor are reduced while the output torque / thrust is ensured to be unchanged, or higher torque / thrust is output under the same current and voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of asynchronous motors, and in particular to a rotor series capacitor asynchronous linear motor and a rotor series capacitor asynchronous rotating motor. Background Art

[0002] The power factor of general asynchronous motors is low, and the conventional methods to improve it include the following:

[0003] 1) Stator-side parallel capacitor: This method connects capacitors in parallel on the stator winding side to absorb reactive power and compensate the grid side, but it cannot improve the power factor of the motor;

[0004] 2) Static phase advancers, dual-winding induction motors, double-fed asynchronous motors, etc.: They require additional power devices and active control, which reduces reliability and is not suitable for installation on skids;

[0005] 3) Wanlass and three-phase capacitor motors: Three-phase capacitor motors add a set of parallel windings on the stator side and connect capacitors in series for power factor compensation. On the one hand, the complexity of the stator side windings is increased, which is not applicable to long stator motors; on the other hand, during the variable frequency speed regulation process, as the frequency of the stator side current changes, there is an impedance mismatch problem, and it is impossible to maintain a high power factor in the full speed range. Summary of the invention

[0006] The present invention provides a rotor series capacitor asynchronous linear motor and a rotor series capacitor asynchronous rotary motor, which can solve the technical problems in the prior art.

[0007] The present invention provides a rotor-series capacitor asynchronous linear motor, wherein the asynchronous linear motor comprises a motor housing and a slip ring, a brush, a stator, a rotor and a capacitor arranged in the motor housing, the stator comprises a stator core and a stator winding, the rotor comprises a rotor core and a rotor winding, and each phase of the rotor winding is connected in series with the capacitor.

[0008] Preferably, each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

[0009] Preferably, each phase of the rotor winding is independently connected in series with the capacitor.

[0010] Preferably, the asynchronous linear motor is driven by a converter, and the stator winding is connected to the converter.

[0011] The present invention also provides a rotor-series capacitor asynchronous rotating motor, wherein the asynchronous rotating motor includes a motor housing and slip rings, brushes, a stator, a rotor and a capacitor arranged in the motor housing, the stator includes a stator core and a stator winding, the rotor includes a rotor core and a rotor winding, and each phase of the rotor winding is connected in series with the capacitor.

[0012] Preferably, each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

[0013] Preferably, each phase of the rotor winding is independently connected in series with the capacitor.

[0014] Preferably, the asynchronous rotating electrical machine is driven by a converter, and the stator winding is connected to the converter.

[0015] Through the above technical solution, the power factor of asynchronous motors (asynchronous linear motors and asynchronous rotary motors) can be effectively improved, and the current and voltage required for motor operation can be reduced while ensuring the output torque / thrust remains unchanged, or higher torque / thrust can be output at the same current and voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic diagram of a rotor string capacitor asynchronous linear motor according to an embodiment of the present invention is shown;

[0018] Figure 2 A schematic diagram of a rotor string capacitor asynchronous linear motor according to another embodiment of the present invention is shown;

[0019] Figure 3 A schematic diagram of a rotor string capacitor asynchronous rotating electrical machine according to an embodiment of the present invention is shown;

[0020] Figure 4 A schematic diagram of a rotor string capacitor asynchronous rotating electrical machine according to another embodiment of the present invention is shown;

[0021] Figure 5A and 5B A comparison diagram of the torque / thrust of a conventional motor and a rotor series capacitor motor versus slip frequency is shown;

[0022] Figure 6A comparison chart showing the voltage variation with slip frequency of a conventional motor and a rotor series capacitor motor is shown. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0025] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0026] Figure 1 A schematic diagram of a rotor string capacitor asynchronous linear motor according to an embodiment of the present invention is shown;

[0027] Figure 2 A schematic diagram of a rotor string capacitor asynchronous linear motor according to another embodiment of the present invention is shown.

[0028] like Figure 1 and 2As shown, an embodiment of the present invention provides a rotor-series capacitor asynchronous linear motor, wherein the asynchronous linear motor includes a motor housing and slip rings, brushes, a stator, a rotor (also called a mover) and a capacitor arranged in the motor housing, the stator includes a stator core and a stator winding, the rotor includes a rotor core and a rotor winding, and each phase of the rotor winding is connected in series with the capacitor.

[0029] Through the above technical solution, the power factor of the asynchronous linear motor can be effectively improved, and the current and voltage required for the motor operation can be reduced while ensuring that the output torque / thrust remains unchanged, or a higher torque / thrust can be output at the same current and voltage.

[0030] According to an embodiment of the present invention, each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

[0031] That is, if Figure 1 As shown, the rotor winding can be connected in series with a capacitor with appropriate capacitance in the form of star connection (that is, the rotor side winding is star connected).

[0032] According to an embodiment of the present invention, alternatively, each phase of the rotor winding is independently connected in series with the capacitor.

[0033] That is, if Figure 2 As shown, each phase winding may be independent and capacitors with appropriate capacitance may be connected in series (ie, each phase of the rotor side winding is independent).

[0034] According to an embodiment of the present invention, the asynchronous linear motor is driven by a converter, and the stator winding is connected to the converter.

[0035] That is, the stator winding can be connected to the converter, and an alternating current can be passed through the stator winding of the asynchronous linear motor through the converter, so that it is coupled with the rotor / mover winding through the action of the spatial magnetic field to generate torque / thrust.

[0036] Figure 3 A schematic diagram of a rotor string capacitor asynchronous rotating electrical machine according to an embodiment of the present invention is shown;

[0037] Figure 4 A schematic diagram of a rotor string capacitor asynchronous rotating electrical machine according to another embodiment of the present invention is shown.

[0038] like Figure 3 and 4As shown, an embodiment of the present invention further provides a rotor-series capacitor asynchronous rotating motor, wherein the asynchronous rotating motor includes a motor housing and slip rings, brushes, a stator, a rotor (also called a mover) and a capacitor arranged in the motor housing, the stator includes a stator core and a stator winding, the rotor includes a rotor core and a rotor winding, and each phase of the rotor winding is connected in series with the capacitor.

[0039] Through the above technical solution, the power factor of asynchronous motors (asynchronous linear motors and asynchronous rotary motors) can be effectively improved, and the current and voltage required for motor operation can be reduced while ensuring the output torque / thrust remains unchanged, or higher torque / thrust can be output at the same current and voltage.

[0040] According to an embodiment of the present invention, each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

[0041] That is, if Figure 3 As shown, the rotor winding can be connected in series with a capacitor with appropriate capacitance in the form of star connection (that is, the rotor side winding is star connected).

[0042] According to an embodiment of the present invention, alternatively, each phase of the rotor winding is independently connected in series with the capacitor.

[0043] That is, if Figure 4 As shown, each phase winding may be independent and capacitors with appropriate capacitance may be connected in series (ie, each phase of the rotor side winding is independent).

[0044] According to an embodiment of the present invention, the asynchronous rotating electrical machine is driven by a converter, and the stator winding is connected to the converter.

[0045] That is, the stator winding can be connected to the converter, and an alternating current can be passed through the stator winding of the asynchronous rotating motor through the converter, so that it is coupled with the rotor / movator winding through the action of the spatial magnetic field to generate torque / thrust.

[0046] In the present invention, the capacitance of the capacitors connected in series can be determined according to actual conditions, and the present invention is not limited to this.

[0047] Figure 5A and Figure 5B The torque / thrust comparison diagram of conventional motor and rotor series capacitor motor is shown. Figure 5A This is a torque / thrust comparison chart of the change in slip frequency when the stator current amplitude is the same. Figure 5B It is aimed at the torque / thrust comparison diagram of the change of current frequency when the stator current amplitude is the same and the slip frequency is fixed.

[0048] Figure 6A comparison chart showing the voltage variation with slip frequency of a conventional motor and a rotor series capacitor motor is shown.

[0049] In Figure 5 and Figure 6 In the figure, the parameters of the conventional motor and the rotor series capacitor motor are the same. Under the same stator current, the comparison results of the torque and voltage of the conventional motor and the rotor series capacitor motor with the change of stator current frequency are obtained.

[0050] It can be seen from the results in the figure that under the same stator current, the rotor series capacitor motor can output higher torque / thrust at a lower input voltage, and the required stator voltage can be lower.

[0051] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0052] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0053] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A rotor series capacitor asynchronous linear motor, characterized in that: The asynchronous linear motor comprises a motor housing and a slip ring, a brush, a stator, a rotor and a capacitor arranged in the motor housing. The stator comprises a stator core and a stator winding. The rotor comprises a rotor core and a rotor winding. Each phase of the rotor winding is connected in series with the capacitor.

2. The asynchronous linear motor according to claim 1, characterized in that: Each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

3. The asynchronous linear motor according to claim 1, characterized in that: The capacitor is connected in series to each phase of the rotor winding independently.

4. The asynchronous linear motor according to any one of claims 1 to 3, characterized in that: The asynchronous linear motor is driven by a converter, and the stator winding is connected to the converter.

5. A rotor series capacitor asynchronous rotating motor, characterized in that: The asynchronous rotating motor comprises a motor housing and a slip ring, a brush, a stator, a rotor and a capacitor arranged in the motor housing. The stator comprises a stator core and a stator winding. The rotor comprises a rotor core and a rotor winding. Each phase of the rotor winding is connected in series with the capacitor.

6. The asynchronous rotating electric machine according to claim 5, characterized in that: Each phase of the rotor winding is connected in series with the capacitor in a star-connected manner.

7. The asynchronous rotating electric machine according to claim 5, characterized in that: The capacitor is connected in series to each phase of the rotor winding independently.

8. The asynchronous rotating electric machine according to any one of claims 5 to 7, characterized in that: The asynchronous rotating electrical machine is driven by a converter, and the stator winding is connected to the converter.

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