A method for starting a piston compressor and a compressor starting device

Abstract

The present invention discloses a method for starting a piston compressor and a compressor starting device. During the starting stage of the piston compressor, a starting positioning point of the rotor is set, that is, when the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor. The positioning signal is used to control the rotor of the compressor to be positioned to a preset position, so that the rotor of the compressor can be reversed to a certain position during the pre-positioning stage of the rotor, so that the rotor of the motor can obtain a certain kinetic energy when it starts to rotate forward and break through the position point with large load / resistance when the compressor is stopped and started, which is conducive to the compressor to smoothly start from a stationary state and then enter the closed-loop control operation stage.

Description

Technical Field

[0001] The present invention relates to the field of compressor startup control, and in particular to a method for starting a piston compressor and a compressor startup device. Background Art

[0002] Currently, the control scheme for controlling compressor startup is generally divided into three stages to control compressor startup, namely the rotor positioning stage, the open-loop startup stage, and the closed-loop control stage. However, the existing control scheme for controlling compressor startup has the following problems: when the compressor is under load, the compressor will stop at a position where the motor has a large resistance to work when it stops after running. When the compressor is restarted at this position with large resistance, it will cause difficulty in starting the compressor. Under this condition, the torque of the compressor is relatively large, which can easily cause the motor speed to fluctuate greatly during the startup process or even fail to rotate normally to enter the closed-loop control stage, resulting in large vibrations when the motor starts, generating vibration noise, or even failure to start. Summary of the Invention

[0003] The present invention aims to solve the technical problems mentioned in the background technology, and provides a method for starting a piston compressor and a compressor starting device to solve the problem of vibration during the starting of the piston compressor.

[0004] In order to achieve the above objectives, the first aspect of the present application provides a method for starting a piston compressor:

[0005] After detecting a start-up instruction of the compressor, the controller inputs a linearly varying direct-axis voltage to the compressor until the direct-axis voltage increases to a set voltage value;

[0006] When the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position;

[0007] determining whether the rotor of the compressor is positioned at a preset position;

[0008] After determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor;

[0009] The compressor is controlled to operate according to the adjusted electrical input parameters.

[0010] Furthermore, when the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position, and includes:

[0011] During the startup of the compressor, when the direct-axis voltage reaches a set voltage value, a specified voltage is input to the compressor to reversely rotate the rotor of the compressor and position it to a preset position;

[0012] The reverse positioning of the rotor of the compressor to the preset position indicates that the piston of the compressor is pulled to a set position corresponding to the preset position.

[0013] Furthermore, after determining whether the rotor of the compressor is positioned at a preset position, the method further includes:

[0014] When it is determined that the rotor of the compressor is not positioned at the preset position, the current position information of the rotor of the compressor is obtained, and a rotor reversal signal is input to the compressor based on the current position information of the rotor of the compressor. The rotor reversal signal is used to control the rotor of the compressor to reverse a first angle.

[0015] Furthermore, after determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor includes:

[0016] obtaining the actual current of the compressor during operation of the compressor and setting a current reference for the compressor during operation;

[0017] If the actual current of the compressor is less than the current reference, increase the motor input duty cycle of the compressor;

[0018] If the actual current of the compressor is greater than the current reference, the motor input duty cycle of the compressor is reduced.

[0019] Furthermore, after determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor, the method further includes:

[0020] Detecting the zero crossing point of the back electromotive force generated in the compressor motor;

[0021] Determine whether the number of zero-crossing points of the back electromotive force generated in the motor of the compressor reaches a set number;

[0022] When the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

[0023] In a second aspect of the present application, a compressor starting device is provided, comprising:

[0024] A first control module is configured to input a linearly varying direct-axis voltage to the compressor after the controller detects a start-up instruction of the compressor, until the direct-axis voltage increases to a set voltage value;

[0025] a second control module, configured to input a positioning signal to the compressor when the direct-axis voltage reaches a set voltage value, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position;

[0026] A first judgment module is used to judge whether the rotor of the compressor is positioned at a preset position;

[0027] a first adjustment module, configured to adjust the electrical input parameters of the compressor in real time according to the load of the compressor after determining that the rotor of the compressor is positioned at the preset position;

[0028] The third control module is configured to control the operation of the compressor according to the adjusted electrical input parameters.

[0029] Furthermore, the second control module includes:

[0030] The first control subunit is connected to the compressor and is used to input a specified voltage to the compressor when the direct-axis voltage reaches a set voltage value during the startup of the compressor, so that the rotor of the compressor is reversed and positioned to a preset position; wherein, the reverse positioning of the rotor of the compressor to the preset position is indicated by the piston of the compressor being pulled to a set position corresponding to the above-mentioned preset position.

[0031] Furthermore, the compressor starting device further includes:

[0032] The fourth control module is used to obtain the current position information of the compressor rotor when it is determined that the compressor rotor is not positioned at the preset position, and input a rotor reversal signal to the compressor according to the current position information of the compressor rotor, wherein the rotor reversal signal is used to control the compressor rotor to reverse a first angle.

[0033] Furthermore, the first adjustment module includes:

[0034] a first acquisition subunit, configured to acquire an actual current of the compressor during operation of the compressor and to set a current reference for the compressor during operation;

[0035] a first execution subunit, configured to increase a motor input duty cycle of the compressor when the actual current of the compressor is less than a current reference;

[0036] The second execution subunit is configured to reduce the motor input duty cycle of the compressor when the actual current of the compressor is greater than the current reference.

[0037] Furthermore, the compressor starting device further includes:

[0038] The second adjustment module is connected to the compressor and is used to detect the zero crossing point of the back electromotive force generated in the compressor motor. When it is determined that the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

[0039] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0040] The present application provides a method for starting a piston compressor. During the starting phase of the piston compressor, a starting positioning point of the rotor is set, that is, when the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor. The positioning signal is used to control the rotor of the compressor to be positioned to a preset position, so that the rotor of the compressor can be reversed to a certain position during the pre-positioning phase of the rotor, so that the rotor of the motor can obtain a certain amount of kinetic energy when it starts to rotate forward and break through the position point with large load / resistance when the compressor is shut down and started, which is conducive to the smooth rotation and start of the compressor from a stationary state and then entering the closed-loop control operation phase.

[0041] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a flow chart of a method for starting a piston compressor shown in this embodiment;

[0043] Figure 2 1 is a schematic structural diagram of a controller in a compressor starting device shown in this embodiment;

[0044] Figure 3 1 is a structural diagram of a second control module in a controller of a compressor starting device shown in this embodiment;

[0045] Figure 4 1 is a structural diagram of a first adjustment module in a controller of a compressor starting device shown in this embodiment. DETAILED DESCRIPTION

[0046] In order to better illustrate the present invention, the present invention is described in further detail below with reference to the accompanying drawings.

[0047] It should be clear that the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the embodiments of the present application.

[0048] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the embodiments of the present application. The singular forms "a," "the," and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0049] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims. In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0050] In addition, in this application, unless otherwise specified, "plurality" refers to two or more. "And / or" describes the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0051] The following describes the first aspect of the present application with reference to specific embodiments. Figure 1 As shown, a method for starting a piston compressor is provided:

[0052] S101: After detecting a start-up instruction of the compressor, the controller inputs a linearly varying direct-axis voltage to the compressor until the direct-axis voltage increases to a set voltage value;

[0053] S102: When the direct-axis voltage reaches a set voltage value, inputting a positioning signal to the compressor, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position;

[0054] S103: Determine whether the rotor of the compressor is positioned at a preset position;

[0055] S104: After determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor;

[0056] S105: Controlling the operation of the compressor according to the adjusted electrical input parameters.

[0057] In actual applications, S101-S102 correspond to the pre-positioning stage of the compressor startup, S103-S104 correspond to the open-loop control stage of the compressor startup, and S105 corresponds to the closed-loop control stage of the compressor startup.

[0058] During the pre-positioning phase of compressor startup, the voltage value of the input direct-axis voltage can vary from 0 to a set voltage value, which is numerically controlled by the controller.

[0059] When the direct-axis voltage reaches the set voltage value, the current generated by the compressor's motor meets the compressor's starting conditions, which are determined by the compressor's own starting rated parameters. At this point, a positioning signal is input to the compressor, instructing the compressor's rotor to be positioned to a preset position. When the compressor's rotor rotates to the preset position, the compressor's piston moves a certain distance relative to the preset position. As the direct-axis voltage continues to increase until it reaches the starting voltage, the compressor's rotor begins forward rotation. At this point, the compressor's rotor is in the preset position, providing initial kinetic energy for the rotor. This corresponding initial kinetic energy is then generated by the compressor's piston during its movement, enabling the rotor to obtain a certain amount of kinetic energy at the beginning of forward rotation to overcome the load / resistance points of the compression process, thereby smoothly rotating and entering the closed-loop control phase.

[0060] Furthermore, after determining that the compressor rotor has been positioned at the preset position, the compressor's electrical input parameters are adjusted in real time based on the compressor's load. In conjunction with the understanding of the solution described in this embodiment, inputting a positioning signal to position the compressor rotor at the preset position is equivalent to inputting a voltage value to the compressor's motor, which is then used to reverse the compressor's rotor. However, an excessively high input voltage value can cause the compressor's motor to draw excessive current, leading to motor demagnetization. Therefore, adjusting the compressor's electrical input parameters in real time based on the compressor's load avoids demagnetization of the compressor's motor due to excessive current, thereby enabling the compressor to smoothly enter the closed-loop control phase.

[0061] In an embodiment of the present application, when the direct axis voltage reaches a set voltage value, a positioning signal is input to the compressor, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position. Figure 2As shown, the second control module 20 of the compressor starting device in the preferred embodiment of the present application includes a first control subunit 201, wherein the first control subunit 201 is connected to the compressor and is used to input a specified voltage to the compressor during the startup of the compressor when the direct-axis voltage reaches a set voltage value, so that the rotor of the compressor is reversed and positioned to a preset position; wherein the reverse positioning of the rotor of the compressor to the preset position is indicated by the piston of the compressor being pulled to a set position corresponding to the above-mentioned preset position.

[0062] Specifically, the specified voltage is determined according to the electrical parameters of the compressor. The first control subunit 201 can use the specified voltage value pre-set in the controller and input the specified voltage into the motor of the compressor to deflect the rotation phase of the motor's rotor, that is, the compressor rotor is reversed. The reversal angle of the compressor rotor is determined by the specified voltage value, so that it is reversed and positioned to a preset position. From the perspective of the mechanical characteristics of the compressor, the motor shaft of the compressor is connected to the piston of the compressor. When the rotor of the compressor reverses, the piston of the compressor is synchronously pulled to a set position corresponding to the preset position, which is equivalent to pulling the piston of the compressor a certain distance.

[0063] Therefore, during the startup pre-positioning stage of the compressor, the rotor of the compressor can be reversed to a position with less load resistance by reversing a certain angle, so that the rotor can obtain a certain amount of kinetic energy within the first circle of rotation to pass through the heavier load point during the compression process.

[0064] In an embodiment of the present application, it is determined whether the rotor of the compressor is positioned at a preset position, such as Figure 2 As shown, the compressor starting device in the preferred embodiment of the present application also includes a fourth judgment module, which is used to obtain the current position information of the compressor rotor when it is determined that the compressor rotor is not positioned at the preset position, and input a rotor reversal signal to the compressor according to the current position information of the compressor rotor, and the rotor reversal signal is used to control the compressor rotor to reverse a first angle.

[0065] During the "start-stop-start" operation process of the compressor, the stop position of the compressor rotor will not completely overlap with the previous stop position. While ensuring that the rotor is restored to the preset position, a judgment process is set, that is, the preset position of the compressor rotor is set and recorded. When the compressor stops, the current position information of the compressor rotor is obtained by controlling it. The position information indicates the stop position of the rotor. By inputting a rotor reversal signal to the compressor, each time the signal is issued, the compressor rotor reverses by a first angle, where the first angle can be manually set in the controller. After multiple repetitions, the rotor reverses to the above-mentioned preset position.

[0066] In an embodiment of the present application, after determining that the rotor of the compressor is positioned at the preset position, the electrical input parameters of the compressor are adjusted in real time according to the load of the compressor, such as Figure 2 and Figure 4 As shown, the first adjustment module 40 in the compressor starting device in the preferred embodiment of the present application includes a first acquisition subunit 401, a first execution subunit 402 and a second execution subunit 403. The first acquisition subunit 401 is used to obtain the actual current of the compressor during the operation of the compressor and set the current reference of the compressor during operation; the first execution subunit 402 is used to increase the motor input duty cycle of the compressor when the actual current of the compressor is less than the current reference; the second execution subunit 403 is used to reduce the motor input duty cycle of the compressor when the actual current of the compressor is greater than the current reference.

[0067] Specifically, the current reference of the compressor during operation is determined according to the rated parameters of the compressor. In order to avoid demagnetization caused by excessive current of the compressor, the current of the compressor motor during operation cannot exceed the rated demagnetization current of the compressor motor itself. For example, the demagnetization current of the DK52 model compressor is 25A, and the demagnetization current of the DM19 model compressor is 20A. Therefore, in this embodiment, the current reference of the compressor during operation is the demagnetization current of the compressor.

[0068] In combination with the above, at this time the compressor rotor is in the open-loop stage of forward rotation. By dynamically adjusting the drive duty cycle of the motor within each carrier cycle, the drive current is controlled so that the motor can obtain a larger starting current without exceeding the current limit value, and start more smoothly.

[0069] The description of the motor driving duty cycle is the ratio of the power-on time of the pulse signal to the power-on period. Increasing the motor input duty cycle of the compressor, taking the compressor motor as a three-phase motor as an example, means increasing the power-on time of two phases in the motor, and vice versa, reducing the power-on time of two phases in the motor.

[0070] In an embodiment of the present application, after determining that the rotor of the compressor is positioned at the preset position, the electrical input parameters of the compressor are adjusted in real time according to the load of the compressor, such as Figure 2 As shown, the compressor starting device in the preferred embodiment of the present application also includes a second adjustment module 50, which is used to detect the zero crossing point of the back electromotive force generated in the compressor motor. When the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

[0071] It should be noted that the back electromotive force generated in the motor is an induced electromotive force generated by the rotation of the motor's rotor cutting through the magnetic lines of force, and its direction is opposite to that of the applied voltage. In this embodiment, the compressor motor is a brushless DC motor, and its output is alternating current. This corresponds to the alternating conversion of this back electromotive force, that is, the voltage must pass through a zero point during the alternating conversion process of the back electromotive force. Combined with the determination and detection of the zero crossing points of the back electromotive force generated in the compressor motor, when the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation. That is, when the number of zero crossing points of the back electromotive force generated in the motor reaches a set number, the operation of the compressor motor tends to be stable, and the controller determines that the motor now meets the conditions for entering closed-loop control operation. The set number of instructions is manually set.

[0072] The second aspect of this application is Figures 2 to 4 As shown, a compressor starting device is provided, comprising:

[0073] The first control module 10 is configured to input a linearly varying direct-axis voltage to the compressor after the controller detects a start-up instruction of the compressor, until the direct-axis voltage increases to a set voltage value;

[0074] a second control module 20, configured to input a positioning signal to the compressor when the direct-axis voltage reaches a set voltage value, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position;

[0075] A first judgment module 30 is used to judge whether the rotor of the compressor is positioned at a preset position;

[0076] A first adjustment module 40 is configured to adjust the electrical input parameters of the compressor in real time according to the load of the compressor after determining that the rotor of the compressor is positioned at the preset position;

[0077] The third control module 60 is configured to control the operation of the compressor according to the adjusted electrical input parameters.

[0078] Furthermore, the second control module 20 includes:

[0079] The first control subunit 201 is connected to the compressor and is used to input a specified voltage to the compressor when the direct-axis voltage reaches a set voltage value during the startup of the compressor, so that the rotor of the compressor is reversed and positioned to a preset position; wherein, the reverse positioning of the rotor of the compressor to the preset position is indicated by the piston of the compressor being pulled to a set position corresponding to the above-mentioned preset position.

[0080] Furthermore, the compressor starting device further includes:

[0081] The fourth control module 70 is used to obtain the current position information of the compressor rotor when it is determined that the compressor rotor is not positioned at the preset position, and input a rotor reversal signal to the compressor according to the current position information of the compressor rotor, wherein the rotor reversal signal is used to control the compressor rotor to reverse a first angle.

[0082] Furthermore, the first adjustment module 40 includes:

[0083] A first acquisition subunit 401 is configured to acquire an actual current of the compressor and set a current reference for the compressor during operation;

[0084] The first execution subunit 402 is configured to increase the motor input duty cycle of the compressor when the actual current of the compressor is less than the current reference;

[0085] The second execution subunit 403 is configured to reduce the motor input duty cycle of the compressor when the actual current of the compressor is greater than the current reference.

[0086] Furthermore, the compressor starting device further includes:

[0087] The second adjustment module 50 is connected to the compressor and is used to detect the zero crossing point of the back electromotive force generated in the compressor motor. When it is determined that the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

[0088] The technical solutions provided by the embodiments of the present application may have the following beneficial effects:

[0089] The present application provides a method for starting a piston compressor. During the starting phase of the piston compressor, a starting positioning point of the rotor is set, that is, when the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor. The positioning signal is used to control the rotor of the compressor to be positioned to a preset position, so that the rotor of the compressor can be reversed to a certain position during the pre-positioning phase of the rotor, so that the rotor of the motor can obtain a certain amount of kinetic energy when it starts to rotate forward and break through the position point with greater load / resistance when the compressor is shut down and started, which is conducive to the smooth rotation of the compressor and entering the closed-loop control operation phase.

[0090] Based on the disclosure and teachings of the above description, those skilled in the art may also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and modifications and variations of the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although certain specific terms are used in this description, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A method for starting a piston compressor, characterized in that: After detecting a start-up instruction of the compressor, the controller inputs a linearly varying direct-axis voltage to the compressor until the direct-axis voltage increases to a set voltage value; When the direct-axis voltage reaches a set voltage value, a positioning signal is input to the compressor, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position; During the startup of the compressor, when the direct-axis voltage reaches a set voltage value, a specified voltage is input to the compressor to reversely rotate the rotor of the compressor and position it to a preset position; The reverse positioning of the rotor of the compressor to the preset position indicates that the piston of the compressor is pulled to a set position corresponding to the preset position; determining whether the rotor of the compressor is positioned at a preset position; When it is determined that the rotor of the compressor is not positioned at the preset position, current position information of the rotor of the compressor is obtained, and a rotor reversal signal is input to the compressor according to the current position information of the rotor of the compressor, wherein the rotor reversal signal is used to control the rotor of the compressor to reverse by a first angle; After determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor; The compressor is controlled to operate according to the adjusted electrical input parameters.

2. The method according to claim 1, characterized in that After determining that the rotor of the compressor is positioned at the preset position, adjusting the electrical input parameters of the compressor in real time according to the load of the compressor includes: obtaining the actual current of the compressor during operation of the compressor and setting a current reference for the compressor during operation; If the actual current of the compressor is less than the current reference, increase the motor input duty cycle of the compressor; If the actual current of the compressor is greater than the current reference, the motor input duty cycle of the compressor is reduced.

3. The method according to claim 2, characterized in that After determining that the rotor of the compressor is positioned at the preset position, and adjusting the electrical input parameters of the compressor in real time according to the load of the compressor, the method further includes: Detecting the zero crossing point of the back electromotive force generated in the compressor motor; Determine whether the number of zero-crossing points of the back electromotive force generated in the motor of the compressor reaches a set number; When the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

4. A compressor starting device, characterized in that: include: A first control module is configured to input a linearly varying direct-axis voltage to the compressor after the controller detects a start-up instruction of the compressor, until the direct-axis voltage increases to a set voltage value; a second control module, configured to input a positioning signal to the compressor when the direct-axis voltage reaches a set voltage value, wherein the positioning signal is used to control the rotor of the compressor to be positioned to a preset position; the second control module includes: a first control subunit, connected to the compressor, for inputting a specified voltage to the compressor when the direct-axis voltage reaches a set voltage value during startup of the compressor, so as to reversely rotate the rotor of the compressor and position it to a preset position; wherein the reverse rotation and positioning of the rotor of the compressor to the preset position is indicated by the piston of the compressor being pulled to a set position corresponding to the preset position; A first judgment module is used to judge whether the rotor of the compressor is positioned at a preset position; a first adjustment module, configured to adjust the electrical input parameters of the compressor in real time according to the load of the compressor after determining that the rotor of the compressor is positioned at the preset position; a third control module, configured to control the operation of the compressor according to the adjusted electrical input parameters; The fourth control module is used to obtain the current position information of the compressor rotor when it is determined that the compressor rotor is not positioned at the preset position, and input a rotor reversal signal to the compressor according to the current position information of the compressor rotor, wherein the rotor reversal signal is used to control the compressor rotor to reverse a first angle.

5. The compressor starting device according to claim 4, characterized in that: The first adjustment module includes: a first acquisition subunit, configured to acquire an actual current of the compressor during operation of the compressor and to set a current reference for the compressor during operation; a first execution subunit, configured to increase a motor input duty cycle of the compressor when the actual current of the compressor is less than a current reference; The second execution subunit is configured to reduce the motor input duty cycle of the compressor when the actual current of the compressor is greater than the current reference.

6. The compressor starting device according to claim 4, characterized in that: The compressor starting device further comprises: The second adjustment module is connected to the compressor and is used to detect the zero crossing point of the back electromotive force generated in the compressor motor. When it is determined that the number of zero crossing points of the back electromotive force generated in the compressor motor reaches a set number, the compressor motor enters closed-loop control operation.

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