Compressor and control method, control device, storage medium and controller thereof

Abstract

This application discloses a compressor and its control method, control device, storage medium, and controller. The method includes: acquiring a bus voltage and a reference vector voltage when the compressor is operating at a frequency within a preset frequency range; determining a first coefficient based on the bus voltage and the reference vector voltage; determining the overmodulation region of the compressor based on the first coefficient; and adjusting the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region and its corresponding overmodulation processing coefficient. Therefore, this method adjusts the d-axis voltage and q-axis voltage of the compressor using different overmodulation processing coefficients according to the overmodulation region of the compressor, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, thereby improving the compressor's speed-up capability and preventing compressor shutdown due to insufficient field weakening during high-frequency operation.

Description

Technical Field

[0001] This application relates to the field of compressor control technology, and in particular to a compressor control method, a compressor control device, a computer-readable storage medium, a controller, and a compressor. Background Technology

[0002] The most significant characteristic of multi-pole, low-layer compressor motors is their high back EMF. A high back EMF indicates better power output, but it also makes them more prone to voltage saturation. In SVPWM (Space Vector Pulse Width Modulation) modulation based on zero-sequence component injection, when voltage saturation leads to overmodulation, the available overmodulation handling methods are limited due to the injection-based modulation method.

[0003] In related technologies, a technique is used to scale the d-axis and q-axis voltages proportionally to a predetermined limit voltage when overmodulation occurs, in order to control overmodulation. However, this technique suffers from insufficient d-axis voltage and excessive q-axis voltage, which causes the compressor to shut down due to insufficient field weakening during high-frequency operation. Summary of the Invention

[0004] This application aims to at least partially solve one of the technical problems in the related art. To this end, the first objective of this application is to propose a compressor control method that adjusts the d-axis voltage and q-axis voltage of the compressor using different overmodulation processing coefficients according to the overmodulation region in which the compressor is located, so as to prioritize ensuring sufficient d-axis voltage and reduce q-axis voltage, thereby maximizing field weakening, improving the compressor's speed-up capability, and preventing the compressor from stopping due to insufficient field weakening during high-frequency operation.

[0005] The second objective of this application is to provide a control device for a compressor.

[0006] The third objective of this application is to provide a computer-readable storage medium.

[0007] The fourth objective of this application is to propose a controller.

[0008] The fifth objective of this application is to propose a compressor.

[0009] To achieve the above objectives, a first aspect of this application proposes a compressor control method, which includes: acquiring a bus voltage and a reference vector voltage when the compressor is operating at a frequency within a preset frequency range; determining a first coefficient based on the bus voltage and the reference vector voltage; determining the overmodulation region where the compressor is located based on the first coefficient; and adjusting the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient.

[0010] According to the compressor control method of this application embodiment, when the compressor operates at a frequency within a preset frequency range, a bus voltage and a reference vector voltage are acquired, a first coefficient is determined based on the bus voltage and the reference vector voltage, and the overmodulation region of the compressor is determined based on the first coefficient. The d-axis voltage and q-axis voltage of the compressor are then adjusted based on the overmodulation region of the compressor and its corresponding overmodulation processing coefficient. Thus, this method adjusts the d-axis voltage and q-axis voltage of the compressor using different overmodulation processing coefficients according to the overmodulation region of the compressor, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, thereby improving the compressor's acceleration capability and preventing compressor shutdown due to insufficient field weakening during high-frequency operation.

[0011] In addition, the compressor control method according to the above embodiments of this application may also have the following additional technical features:

[0012] According to one embodiment of this application, determining the overmodulation region of the compressor based on a first coefficient includes: determining the overmodulation region of the compressor as a first overmodulation region when the first coefficient is within a first preset range; and determining the overmodulation region of the compressor as a second overmodulation region when the first coefficient is within a second preset range, wherein the upper limit of the first preset range is equal to the lower limit of the second preset range.

[0013] According to one embodiment of this application, adjusting the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient includes: when the overmodulation region where the compressor is located is a first overmodulation region, determining a second coefficient based on the upper limit of a first preset range; determining a first d-axis voltage limit value based on a first product between the second coefficient, the bus voltage, and the first preset coefficient, and the product of the first product and the first overmodulation processing coefficient corresponding to the first overmodulation region; determining a target d-axis voltage as the d-axis voltage when the d-axis voltage is less than the first d-axis voltage limit value; determining a target d-axis voltage as the first d-axis voltage limit value when the d-axis voltage is greater than or equal to the first d-axis voltage limit value; and determining a target q-axis voltage based on a first difference between the square of the first product and the square of the target d-axis voltage, and the square root of the first difference.

[0014] According to one embodiment of this application, adjusting the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient includes: when the overmodulation region where the compressor is located is a second overmodulation region, determining a third coefficient based on the upper limit of a second preset range; determining a second d-axis voltage limit value based on a second product between the third coefficient, the bus voltage, and the second preset coefficient, and the product of the second product and the second overmodulation processing coefficient corresponding to the second overmodulation region; determining a target d-axis voltage as the d-axis voltage when the d-axis voltage is less than the second d-axis voltage limit value; determining a target d-axis voltage as the second d-axis voltage limit value when the d-axis voltage is greater than or equal to the second d-axis voltage limit value; and determining a target q-axis voltage based on a second difference between the square of the second product and the square of the target d-axis voltage, and the square root of the second difference.

[0015] According to one embodiment of this application, the first overmodulation processing coefficient is smaller than the second overmodulation processing coefficient.

[0016] According to one embodiment of this application, the compressor control method further includes: determining that the compressor is in a no-overmodulation region when the first coefficient is less than or equal to the lower limit of the first preset range, and determining the target d-axis voltage as the d-axis voltage and the target q-axis voltage as the q-axis voltage.

[0017] According to one embodiment of this application, determining a first coefficient based on a bus voltage and a reference vector voltage includes: obtaining the ratio between the reference vector voltage and the bus voltage; and determining the first coefficient based on the product of the ratio and a preset coefficient.

[0018] According to one embodiment of this application, obtaining a reference vector voltage includes: obtaining a d-axis voltage and a q-axis voltage; and determining the reference vector voltage based on the sum of the squares of the d-axis voltage and the square root of the sum.

[0019] To achieve the above objectives, a second aspect of this application provides a compressor control device, comprising: an acquisition module for acquiring a bus voltage and a reference vector voltage when the compressor is operating at a frequency within a preset frequency range; a determination module for determining a first coefficient based on the bus voltage and the reference vector voltage; and a control module for determining the overmodulation region of the compressor based on the first coefficient, and adjusting the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region of the compressor and its corresponding overmodulation processing coefficient.

[0020] According to the compressor control device of this application embodiment, the acquisition module acquires the bus voltage and reference vector voltage when the compressor is operating at a frequency within a preset frequency range. The determination module determines a first coefficient based on the bus voltage and reference vector voltage. The control module determines the overmodulation region of the compressor based on the first coefficient and adjusts the d-axis and q-axis voltages of the compressor according to the overmodulation region and its corresponding overmodulation processing coefficient. Thus, the device adjusts the d-axis and q-axis voltages of the compressor using different overmodulation processing coefficients based on the overmodulation region, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, improve the compressor's acceleration capability, and prevent compressor shutdown due to insufficient field weakening during high-frequency operation.

[0021] To achieve the above objectives, a third aspect of this application provides a computer-readable storage medium storing a compressor control program thereon, which, when executed by a processor, implements the compressor control method described above.

[0022] According to the computer-readable storage medium of the present application embodiment, when the compressor control program is executed by the processor, the above-described compressor control method is implemented. Based on the above-described compressor control method, sufficient d-axis voltage is prioritized, and q-axis voltage is reduced to maximize field weakening, thereby improving the compressor's speed-up capability and preventing compressor shutdown due to insufficient field weakening during high-frequency operation.

[0023] To achieve the above objectives, a fourth aspect of this application provides a controller, including a memory, a processor, and a compressor control program stored in the memory and executable on the processor. When the processor executes the compressor control program, it implements the compressor control method described above.

[0024] According to the controller of the present application embodiment, when the processor executes the compressor control program, it implements the above-mentioned compressor control method. Based on the above-mentioned compressor control method, it prioritizes ensuring sufficient d-axis voltage and reduces q-axis voltage to maximize field weakening, improve the compressor's speed-up capability, and prevent the compressor from stopping due to insufficient field weakening during high-frequency operation.

[0025] To achieve the above objectives, a fifth aspect of this application provides a compressor, including a control device for the compressor or a controller.

[0026] According to the embodiments of this application, the compressor, based on the control device or controller of the compressor, improves the compressor's speed-up capability and prevents shutdown due to insufficient weak magnetism during high-frequency operation.

[0027] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0028] Figure 1 This is a flowchart of a compressor control method according to an embodiment of this application;

[0029] Figure 2 This is a flowchart of a compressor control method according to an embodiment of this application;

[0030] Figure 3 This is a schematic diagram of the connection of the control device of the compressor according to an embodiment of this application;

[0031] Figure 4 This is a block diagram of a controller according to an embodiment of this application;

[0032] Figure 5 This is a block diagram of a compressor according to one embodiment of the present application;

[0033] Figure 6 This is a block diagram of a compressor according to another embodiment of this application. Detailed Implementation

[0034] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0035] The following description, with reference to the accompanying drawings, outlines a compressor control method, a compressor control device, a computer-readable storage medium, a controller, and a compressor according to embodiments of this application.

[0036] With increasingly stringent global requirements for energy conservation and environmental protection, and ever-more stringent customer demands for lower air conditioning prices and reduced noise levels, the compressor, as the core power unit of an air conditioner, must shoulder the responsibility of reducing noise, improving energy efficiency, and lowering costs. Therefore, as the heart of the compressor, the motor's mission in this era is to pursue the ultimate in cost-effectiveness and continuously explore optimal structural topologies.

[0037] Multi-pole, low-thickness compressor motors achieve higher power density by increasing the number of pole pairs and enhancing pole-slot matching. This allows for a lower stack thickness, resulting in smaller, lighter compressor motors and ultimately lower costs. However, the most significant characteristic of multi-pole, low-thickness compressor motors is their high back EMF. While a high back EMF indicates better power output, it also makes them more prone to voltage saturation.

[0038] In related technologies, when the compressor motor is overmodulated, voltage regulation is achieved by proportionally scaling the d-axis voltage to a specified limit voltage. However, in practical applications, the applicant has found that for multi-pole, low-layer-thickness compressors, using the proportional scaling method results in insufficient d-axis voltage and excessive q-axis voltage. This causes the compressor to shut down at high frequencies due to insufficient field weakening.

[0039] To address at least one of the aforementioned technical problems, this application proposes a compressor control method. When the compressor operates at a frequency within a preset frequency range, the method acquires the bus voltage and reference vector voltage, determines a first coefficient based on the bus voltage and reference vector voltage, and determines the overmodulation region of the compressor based on the first coefficient. The method then adjusts the d-axis voltage and q-axis voltage of the compressor according to the overmodulation region and its corresponding overmodulation processing coefficient. This allows for the adjustment of the compressor's d-axis and q-axis voltages using different overmodulation processing coefficients based on the overmodulation region, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, thereby enhancing the compressor's acceleration capability and preventing compressor shutdown due to insufficient field weakening during high-frequency operation.

[0040] The control method of the compressor of this application will be described in detail below with reference to the accompanying drawings.

[0041] like Figure 1 As shown, the compressor control method of this application embodiment may include:

[0042] S1, when the compressor is running at a frequency within a preset frequency range, obtain the bus voltage Vdc and the reference vector voltage Vs;

[0043] S2, determine the first coefficient M1 based on the bus voltage Vdc and the reference vector voltage Vs;

[0044] S3. Determine the overmodulation region of the compressor based on the first coefficient M1, and adjust the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region of the compressor and its corresponding overmodulation processing coefficient.

[0045] Specifically, the preset frequency range can be set according to the actual situation. For example, the preset frequency range can be a relatively high frequency range, so as to control the compressor in high-frequency operation through the compressor control method.

[0046] The bus voltage Vdc is acquired by a voltage acquisition unit, and the target voltage is obtained based on a preset voltage control strategy. Then, the reference vector voltage Vs is determined based on the target voltage. For example, the reference vector voltage Vs is calculated using the d-axis and q-axis voltages obtained through the control strategy.

[0047] The first coefficient M1 is determined based on the relationship between the bus voltage Vdc and the reference vector voltage Vs. M1 is used to assess the current overmodulation level of the compressor, and then the overmodulation region where the compressor is currently located is determined based on M1. Specifically, multiple preset overmodulation regions can be obtained based on the setting of multiple preset coefficients. The interval is determined by the relationship between the first coefficient M1 and the preset coefficients, and the preset overmodulation region corresponding to this interval is taken as the overmodulation region where the compressor is currently located.

[0048] In addition, different overmodulation processing coefficients are set for each preset overmodulation region to meet the voltage regulation requirements of compressors in different overmodulation regions and ensure their stable operation. For example, three pre-set overmodulation regions are designated as the first overmodulation region, the second overmodulation region, and the third overmodulation region. The first overmodulation region corresponds to the first coefficient range and the first overmodulation processing coefficient; the second overmodulation region corresponds to the second coefficient range and the second overmodulation processing coefficient; and the third overmodulation region corresponds to the third coefficient range and the third overmodulation processing coefficient. The calculated first coefficient M1 is compared with the aforementioned first, second, and third coefficient ranges. If the first coefficient M1 falls within the third coefficient range, the compressor is determined to be in the third overmodulation region. The d-axis voltage and q-axis voltage of the compressor are then adjusted using the third overmodulation processing coefficient to maximize the strength of the field weakening voltage, i.e., the d-axis voltage, and avoid compressor shutdown due to insufficient field weakening.

[0049] When the compressor operates at high frequency, the back EMF is the main voltage drain, requiring only a small amount of q-axis voltage to maintain operation. For the compressor to operate at high frequency, sufficient field weakening, i.e., a sufficient d-axis voltage, is a necessary condition. This embodiment employs a variable-proportion overmodulation technique to maximize the sufficiency of the d-axis voltage and improve the compressor's operational stability.

[0050] In one embodiment of this application, determining the overmodulation region of the compressor based on a first coefficient M1 includes: determining the overmodulation region of the compressor as a first overmodulation region when the first coefficient M1 is within a first preset range; and determining the overmodulation region of the compressor as a second overmodulation region when the first coefficient M1 is within a second preset range, wherein the upper limit of the first preset range is equal to the lower limit of the second preset range.

[0051] In other words, the first and second preset intervals can be set according to actual conditions to classify the degree of overmodulation of the compressor. It is assumed that a higher value of the first coefficient M1 indicates a higher degree of overmodulation of the compressor, meaning that compressors within the second preset interval have a higher degree of overmodulation. For example, if the first preset interval is (1.15, 1.25] and the second preset interval is (1.25, 1.33], then when 1.15 < M1 ≤ 1.25, the compressor is determined to be in the first overmodulation region; when 1.25 < M1 ≤ 1.33, the compressor is determined to be in the second overmodulation region.

[0052] In one embodiment of this application, adjusting the d-axis voltage and q-axis voltage of the compressor according to the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient includes: when the overmodulation region where the compressor is located is a first overmodulation region, determining a second coefficient M2 based on the upper limit of a first preset range; determining a first d-axis voltage limit value Vdmax1 based on a first product between the second coefficient M2, the bus voltage Vdc, and the first preset coefficient K1, and the product of the first product and the first overmodulation processing coefficient Kh1 corresponding to the first overmodulation region; determining a target d-axis voltage Vdlimit as the d-axis voltage Vd when the d-axis voltage Vd is less than the first d-axis voltage limit value Vdmax1; determining a target d-axis voltage Vdlimit as the first d-axis voltage limit value Vdmax1 when the d-axis voltage Vd is greater than or equal to the first d-axis voltage limit value Vdmax1; and determining a target q-axis voltage Vqlimit based on a first difference between the square of the first product and the square of the target d-axis voltage Vdlimit, and the square root of the first difference.

[0053] Specifically, taking the first preset interval range of (1.15, 1.25) as an example, if 1.15 < M1 ≤ 1.25, the compressor is determined to be in the first overmodulation region, and the second coefficient M2 is 1.25.

[0054] The first d-axis voltage limit value Vdmax1 is calculated using the following formula:

[0055] Vdmax1=Kh1*(M2*Vdc*K1) (1)

[0056] Wherein, Vdmax1 represents the first d-axis voltage limit value, Kh1 represents the first overmodulation processing coefficient, M2 represents the second coefficient, Vdc represents the bus voltage, and K1 represents the first preset coefficient.

[0057] Further, the first preset coefficient can be set according to the actual situation, such as 0.5. The first overmodulation coefficient can be set according to the actual situation. For example, the value range of the first overmodulation coefficient is 0.8 - 0.85, and the specific value can be determined according to the calculated first coefficient M1 or set according to user selection, which is not limited here.

[0058] The calculated first d-axis voltage limit value Vdmax1 is the upper limit value of the d-axis voltage corresponding to the first overmodulation region, which is used to limit the d-axis voltage. The smaller voltage value between the d-axis voltage Vd and the first d-axis voltage limit value Vdmax1 is used as the target d-axis voltage Vdlimit. That is, if Vd < Vdmax1, then Vdlimit = Vd; otherwise, Vdlimit = Vdmax1.

[0059] Calculate the target q-axis voltage Vqlimit according to the following formula:

[0060]

[0061] Among them, Vqlimit represents the target q-axis voltage, M2 * Vdc * K1 represents the first product, M2 represents the second coefficient, Vdc represents the bus voltage, K1 represents the first preset coefficient, and Vdlimit represents the target d-axis voltage.

[0062] In an embodiment of the present application, the d-axis voltage and q-axis voltage of the compressor are adjusted according to the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient, including: when the overmodulation region where the compressor is located is the second overmodulation region, determining the third coefficient M3 according to the upper limit value of the second preset interval range; determining the second d-axis voltage limit value Vdmax2 according to the second product of the third coefficient M3, the bus voltage Vdc and the second preset coefficient K2, and the product of the second product and the second overmodulation processing coefficient Kh2 corresponding to the second overmodulation region; when the d-axis voltage Vd is less than the second d-axis voltage limit value Vdmax2, determining the target d-axis voltage Vdlimit as the d-axis voltage Vd; when the d-axis voltage Vd is greater than or equal to the second d-axis voltage limit value Vdmax2, determining the target d-axis voltage Vdlimit as the second d-axis voltage limit value Vdmax2; determining the target q-axis voltage Vqlimit according to the second difference between the square of the second product and the square of the target d-axis voltage Vdlimit, and the square root of the second difference.

[0063] Specifically, continuing to take the second preset interval range as (1.25, 1.33] as an example, when 1.25 < M1 ≤ 1.33 is satisfied, it is determined that the compressor is in the second overmodulation region, and the third coefficient M3 is determined to be 1.33.

[0064] The second d-axis voltage limit value Vdmax2 is calculated by the following formula:

[0065] Vdmax2 = Kh2 * (M3 * Vdc * K2) (3)

[0066] Where, Vdmax2 represents the second d-axis voltage limit value, Kh2 represents the second overmodulation processing coefficient, M3 represents the third coefficient, Vdc represents the bus voltage, and K2 represents the second preset coefficient.

[0067] Furthermore, the second preset coefficient K2 can be set according to the actual situation, such as 0.5. The second overmodulation coefficient Kh2 can be set according to the actual situation. The second overmodulation coefficient Kh2 can be greater than the first overmodulation coefficient Kh1. For example, the value range of the first overmodulation coefficient Kh1 is 0.8 - 0.85, then the value range of the second overmodulation coefficient is 0.85 - 0.9. The specific value can be determined according to the calculated first coefficient M1 or set according to user selection, and there is no limitation here.

[0068] The calculated second d-axis voltage limit value Vdmax2 is the upper limit value of the d-axis voltage corresponding to the second overmodulation region, which is used to limit the d-axis voltage. The smaller voltage value between the d-axis voltage Vd and the second d-axis voltage limit value Vdmax2 is used as the target d-axis voltage Vdlimit. That is, if Vd < Vdmax2, then Vdlimit = Vd; otherwise, Vdlimit = Vdmax2.

[0069] The target q-axis voltage Vqlimit is calculated according to the following formula:

[0070]

[0071] Where, Vqlimit represents the target q-axis voltage, M3 * Vdc * K2 represents the second product, M3 represents the third coefficient, Vdc represents the bus voltage, K2 represents the second preset coefficient, and Vdlimit represents the target d-axis voltage.

[0072] In an embodiment of the present application, the first overmodulation processing coefficient Kh1 is less than the second overmodulation processing coefficient Kh2. When the overmodulation degree of the compressor is relatively strong, the weak magnetic field is enhanced by increasing the distribution ratio of the d-axis voltage, and the speed-up performance of the compressor is improved.

[0073] In an embodiment of the present application, the control method of the compressor further includes: when the first coefficient M1 is less than or equal to the lower limit value of the first preset interval range, it is determined that the compressor is in the non-overmodulation region, and the target d-axis voltage Vdlimit is determined as the d-axis voltage Vd, and the target q-axis voltage Vqlimit is determined as the q-axis voltage Vq.

[0074] Specifically, taking the first preset interval range of (1.15, 1.25] as an example, when the calculated first coefficient M1≤1.15, it is determined that the compressor is in the no-overmodulation region, and the target d-axis voltage Vdlimit=Vd and the target q-axis voltage Vqlimit=Vq participate in the duty cycle calculation.

[0075] In addition, taking the second preset range of (1.25, 1.33) as an example, when the calculated first coefficient M1 > 1.33, the d-axis voltage and q-axis voltage of the compressor can be adjusted according to the control method when the compressor is in the second overmodulation region.

[0076] According to one embodiment of this application, determining a first coefficient M1 based on a bus voltage Vdc and a reference vector voltage Vs includes: obtaining the ratio between the reference vector voltage Vs and the bus voltage Vdc; and determining the first coefficient M1 based on the product of the ratio and a preset coefficient k.

[0077] In other words, the first coefficient is calculated using the following formula:

[0078]

[0079] Where M1 represents the first coefficient, Vs represents the reference vector voltage, Vdc represents the bus voltage, and k represents the preset coefficient, which can be set according to the actual situation, for example, 0.5.

[0080] In one embodiment of this application, obtaining the reference vector voltage Vs includes: obtaining the d-axis voltage and the q-axis voltage; and determining the reference vector voltage Vs based on the sum of the squares of the d-axis voltage and the square root of the sum.

[0081] Specifically, based on the d-axis voltage Vd and q-axis voltage Vq obtained from FOC (Field-Oriented Control), the reference vector voltage is calculated using the following formula:

[0082]

[0083] Where Vs represents the reference vector voltage, Vd represents the d-axis voltage, and Vq represents the q-axis voltage.

[0084] As a specific embodiment of this application, taking a first preset interval range of (1.15, 1.25] and a second preset interval range of (1.25, 1.33] as an example, the compressor control method is as follows: Figure 2 As shown, the following steps may be included:

[0085] S101, based on FOC control, obtains the d-axis voltage Vd and the q-axis voltage Vq.

[0086] S102, Calculate the reference vector voltage

[0087] S103, Calculate the first coefficient

[0088] S104, determine if M1 is greater than 1.15. If yes, proceed to step S105; otherwise, proceed to step S118.

[0089] S105, determine if M1 is greater than 1.25. If yes, proceed to step S106; otherwise, proceed to step S112.

[0090] S106, determine the third coefficient M3 = 1.33.

[0091] S107, calculate the second d-axis voltage limit value Vdmax2=Kh2*(M3*Vdc*K2).

[0092] S108, determine whether the current voltage Vd is greater than or equal to Vdmax2. If yes, proceed to step S109; otherwise, proceed to step S110.

[0093] S109, Target d-axis voltage Vdlimit = Vdmax2. Execute step S111.

[0094] S110, target d-axis voltage Vdlimit=Vd.

[0095] S111, Calculate the target q-axis voltage

[0096] S112, determine the second coefficient M2 = 1.25.

[0097] S113, calculate the first d-axis voltage limit value Vdmax1=Kh1*(M2*Vdc*K1).

[0098] S114. Determine whether the current voltage Vd is greater than or equal to Vdmax1. If yes, proceed to step S115; otherwise, proceed to step S116.

[0099] S115, Target d-axis voltage Vdlimit = Vdmax1. Execute step S117.

[0100] S116, target d-axis voltage Vdlimit=Vd.

[0101] S117, Calculate the target q-axis voltage

[0102] S118, the target d-axis voltage Vdlimit = Vd, and the target q-axis voltage Vqlimit = Vq. Compressor control is then performed based on the target d-axis and target q-axis voltages.

[0103] Therefore, this embodiment calculates and tests the required range of d-axis voltage based on the overmodulation region, and determines the overmodulation processing coefficient based on the range (the second overmodulation region is Kh1, and the second overmodulation region is Kh2). Based on this coefficient, when the system voltage saturates and enters overmodulation, the d-axis voltage is prioritized to be sufficient, while the q-axis voltage is reduced. This is a variable scaling method. Using this method can maximize the field weakening and improve the compressor's speed-up capability.

[0104] In summary, the compressor control method according to the embodiments of this application, when the compressor operates at a frequency within a preset frequency range, acquires the bus voltage and reference vector voltage, determines a first coefficient based on the bus voltage and reference vector voltage, determines the overmodulation region of the compressor based on the first coefficient, and adjusts the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region of the compressor and its corresponding overmodulation processing coefficient. Therefore, this method adjusts the d-axis voltage and q-axis voltage of the compressor using different overmodulation processing coefficients according to the overmodulation region of the compressor, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, improve the compressor's acceleration capability, and prevent compressor shutdown due to insufficient field weakening during high-frequency operation.

[0105] Corresponding to the above embodiments, this application also proposes a compressor control device.

[0106] like Figure 3 As shown, the compressor control device in this application embodiment may include: an acquisition module 10, a determination module 20, and a control module 30.

[0107] The acquisition module 10 acquires the bus voltage and reference vector voltage when the compressor operates at a frequency within a preset frequency range. The determination module 20 determines a first coefficient based on the bus voltage and reference vector voltage. The control module 30 determines the overmodulation region of the compressor based on the first coefficient and adjusts the d-axis and q-axis voltages of the compressor according to the overmodulation region and its corresponding overmodulation processing coefficient.

[0108] According to one embodiment of this application, the control module 30 determines the overmodulation region where the compressor is located based on a first coefficient, specifically configured to: determine the overmodulation region where the compressor is located as a first overmodulation region when the first coefficient is within a first preset range; and determine the overmodulation region where the compressor is located as a second overmodulation region when the first coefficient is within a second preset range, wherein the upper limit of the first preset range is equal to the lower limit of the second preset range.

[0109] According to one embodiment of this application, the control module 30 adjusts the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient. Specifically, it is used to: determine a second coefficient based on the upper limit of a first preset range when the overmodulation region where the compressor is located is a first overmodulation region; determine a first d-axis voltage limit value based on a first product between the second coefficient, the bus voltage, and the first preset coefficient, and the product of the first product and the first overmodulation processing coefficient corresponding to the first overmodulation region; determine a target d-axis voltage when the d-axis voltage is less than the first d-axis voltage limit value; determine a target d-axis voltage as the first d-axis voltage limit value when the d-axis voltage is greater than or equal to the first d-axis voltage limit value; and determine a target q-axis voltage based on a first difference between the square of the first product and the square of the target d-axis voltage, and the square root of the first difference.

[0110] According to one embodiment of this application, the control module 30 adjusts the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region where the compressor is located and its corresponding overmodulation processing coefficient. Specifically, it is used to: determine a third coefficient based on the upper limit of a second preset range when the overmodulation region where the compressor is located is a second overmodulation region; determine a second d-axis voltage limit value based on the second product between the third coefficient, the bus voltage, and the second preset coefficient, and the product of the second product and the second overmodulation processing coefficient corresponding to the second overmodulation region; determine a target d-axis voltage when the d-axis voltage is less than the second d-axis voltage limit value; determine a target d-axis voltage as the second d-axis voltage limit value when the d-axis voltage is greater than or equal to the second d-axis voltage limit value; and determine a target q-axis voltage based on the second difference between the square of the second product and the square of the target d-axis voltage, and the square root of the second difference.

[0111] According to one embodiment of this application, the first overmodulation processing coefficient is smaller than the second overmodulation processing coefficient.

[0112] According to one embodiment of this application, the control module 30 is further configured to: determine that the compressor is in an overmodulation-free region when the first coefficient is less than or equal to the lower limit of the first preset range, and determine the target d-axis voltage as the d-axis voltage and the target q-axis voltage as the q-axis voltage.

[0113] According to one embodiment of this application, the determining module 20 determines a first coefficient based on the bus voltage and the reference vector voltage, specifically used for: obtaining the ratio between the reference vector voltage and the bus voltage; and determining the first coefficient based on the product of the ratio and a preset coefficient.

[0114] According to one embodiment of this application, the acquisition module 10 acquires a reference vector voltage, specifically for: acquiring the d-axis voltage and the q-axis voltage; and determining the reference vector voltage based on the sum of the squares of the d-axis voltage and the square root of the sum.

[0115] It should be noted that for details not disclosed in the compressor control device of the embodiments of this application, please refer to the details disclosed in the compressor control method of the above embodiments of this application, which will not be repeated here.

[0116] According to the compressor control device of this application embodiment, the acquisition module acquires the bus voltage and reference vector voltage when the compressor is operating at a frequency within a preset frequency range. The determination module determines a first coefficient based on the bus voltage and reference vector voltage. The control module determines the overmodulation region of the compressor based on the first coefficient and adjusts the d-axis and q-axis voltages of the compressor according to the overmodulation region and its corresponding overmodulation processing coefficient. Thus, the device adjusts the d-axis and q-axis voltages of the compressor using different overmodulation processing coefficients based on the overmodulation region, prioritizing sufficient d-axis voltage and reducing q-axis voltage to maximize field weakening, improve the compressor's acceleration capability, and prevent compressor shutdown due to insufficient field weakening during high-frequency operation.

[0117] Corresponding to the above embodiments, this application also proposes a computer-readable storage medium.

[0118] The computer-readable storage medium of this application embodiment stores a compressor control program thereon, which, when executed by a processor, implements the compressor control method described above.

[0119] According to the computer-readable storage medium of the present application embodiment, when the compressor control program is executed by the processor, the above-described compressor control method is implemented. Based on the above-described compressor control method, different overmodulation processing coefficients are used to adjust the d-axis voltage and q-axis voltage of the compressor, so as to prioritize ensuring sufficient d-axis voltage and reduce q-axis voltage, thereby maximizing field weakening, improving the compressor's speed-up capability, and preventing the compressor from stopping due to insufficient field weakening during high-frequency operation.

[0120] Corresponding to the above embodiments, this application also proposes a controller.

[0121] like Figure 4 As shown, the controller 100 in this embodiment includes a memory 110, a processor 120, and a compressor control program stored in the memory 110 and executable on the processor 120. When the processor 120 executes the compressor control program, it implements the compressor control method described above.

[0122] According to the controller of the present application embodiment, when the processor executes the compressor control program, it implements the above-mentioned compressor control method. Based on the above-mentioned compressor control method, different overmodulation processing coefficients are used to adjust the d-axis voltage and q-axis voltage of the compressor, so as to prioritize ensuring the sufficiency of the d-axis voltage and reduce the q-axis voltage, thereby maximizing the field weakening, improving the compressor's speed-up capability, and preventing the compressor from stopping due to insufficient field weakening when the compressor is running at high frequency.

[0123] Corresponding to the above embodiments, this application also proposes a compressor.

[0124] like Figure 5 As shown, the compressor 200 in this embodiment includes the control device 210 of the compressor described above, or as... Figure 6 As shown, the compressor 200 in this embodiment includes the controller 100 described above.

[0125] According to the compressor of the present application embodiment, based on the compressor control device or the controller, the d-axis voltage is prioritized to be sufficient, the q-axis voltage is reduced, the field weakening is maximized, the compressor speed-up capability is improved, and the compressor shutdown is prevented due to insufficient field weakening during high-frequency operation.

[0126] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0127] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0128] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0129] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0130] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0131] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A control method of a compressor, characterized by, The method includes: When the compressor operates at a frequency within a preset frequency range, the bus voltage and reference vector voltage are obtained; The first coefficient is determined based on the bus voltage and the reference vector voltage; The overmodulation region of the compressor is determined based on the first coefficient, and the d-axis voltage and q-axis voltage of the compressor are adjusted according to the overmodulation region of the compressor and its corresponding overmodulation processing coefficient.

2. The method of claim 1, wherein, Determining the overmodulation region of the compressor based on the first coefficient includes: If the first coefficient is within the first preset range, the overmodulation region where the compressor is located is determined to be the first overmodulation region; When the first coefficient is within the range of the second preset interval, the overmodulation region where the compressor is located is determined to be the second overmodulation region, wherein the upper limit of the first preset interval range is equal to the lower limit of the second preset interval range.

3. The method according to claim 2, characterized in that, The d-axis and q-axis voltages of the compressor are adjusted according to the overmodulation region in which the compressor is located and its corresponding overmodulation processing coefficient, including: When the compressor is located in the overmodulation region, which is the first overmodulation region, the second coefficient is determined based on the upper limit of the first preset interval range. The first d-axis voltage limit value is determined based on the first product between the second coefficient, the bus voltage, and the first preset coefficient, and the product of the first product and the first overmodulation processing coefficient corresponding to the first overmodulation region. When the d-axis voltage is less than the first d-axis voltage limit value, the target d-axis voltage is determined to be the d-axis voltage; When the d-axis voltage is greater than or equal to the first d-axis voltage limit value, the target d-axis voltage is determined to be the first d-axis voltage limit value; The target q-axis voltage is determined based on the first difference between the square of the first product and the square of the target d-axis voltage, and the square root of the first difference.

4. The method according to claim 2, characterized in that, The d-axis and q-axis voltages of the compressor are adjusted according to the overmodulation region in which the compressor is located and its corresponding overmodulation processing coefficient, including: When the overmodulation region where the compressor is located is the second overmodulation region, the third coefficient is determined based on the upper limit of the second preset interval range; The second d-axis voltage limit value is determined based on the second product between the third coefficient, the bus voltage, and the second preset coefficient, and the product of the second product and the second overmodulation processing coefficient corresponding to the second overmodulation region. When the d-axis voltage is less than the second d-axis voltage limit value, the target d-axis voltage is determined to be the d-axis voltage; When the d-axis voltage is greater than or equal to the second d-axis voltage limit value, the target d-axis voltage is determined to be the second d-axis voltage limit value; The target q-axis voltage is determined based on the second difference between the square of the second product and the square of the target d-axis voltage, and the square root of the second difference.

5. The method according to claim 3 or 4, characterized in that, The first overmodulation coefficient is less than the second overmodulation coefficient.

6. The method according to claim 2, characterized in that, The method further includes: When the first coefficient is less than or equal to the lower limit of the first preset range, the compressor is determined to be in the no-overmodulation region, the target d-axis voltage is determined to be the d-axis voltage, and the target q-axis voltage is determined to be the q-axis voltage.

7. The method according to claim 1, characterized in that, The step of determining the first coefficient based on the bus voltage and the reference vector voltage includes: Obtain the ratio between the reference vector voltage and the bus voltage; The first coefficient is determined by multiplying the ratio by a preset coefficient.

8. The method according to claim 1, characterized in that, Obtaining the reference vector voltage includes: Obtain the d-axis voltage and q-axis voltage; The reference vector voltage is determined based on the sum of the squares of the d-axis voltage and the squares of the q-axis voltage, and the square root of the sum.

9. A control device for a compressor, characterized in that, include: The acquisition module is used to acquire the bus voltage and the reference vector voltage when the compressor is operating at a frequency within a preset frequency range; The determining module is used to determine a first coefficient based on the bus voltage and the reference vector voltage; The control module is used to determine the overmodulation region of the compressor based on the first coefficient, and to adjust the d-axis voltage and q-axis voltage of the compressor based on the overmodulation region of the compressor and its corresponding overmodulation processing coefficient.

10. A computer-readable storage medium, characterized in that, It stores a compressor control program, which, when executed by a processor, implements the compressor control method according to any one of claims 1-8.

11. A controller, characterized in that, The system includes a memory, a processor, and a compressor control program stored in the memory and executable on the processor. When the processor executes the compressor control program, it implements the compressor control method according to any one of claims 1-8.

12. A compressor, characterized in that, It includes the control device for the compressor as described in claim 9, or the controller as described in claim 11.

Images