Compressor start-up control method, apparatus, compressor, and medium

Abstract

The application discloses a kind of compressor starting control method, device, compressor and medium, first based on the mode of speed open loop starts compressor, and obtains the current starting duration and current feedback speed of compressor;On the premise that current starting duration satisfies maintaining starting condition, and current feedback speed does not satisfy speed closed loop condition, the cumulative duration that current feedback speed exceeds speed preset range is counted, if cumulative duration is greater than preset cumulative duration threshold, then determine that the pressure difference between suction pipe and exhaust pipe of compressor is greater than preset threshold, drive compressor to stop. That is, the time accumulation of speed fluctuation is used as the judgment condition whether the pressure difference between suction pipe and exhaust pipe is greater than preset threshold, so that the pressure difference between suction pipe and exhaust pipe of compressor is determined to be greater than preset threshold and stopped in advance, the compressor can be stopped before or just after the noise occurs, effectively reduce noise level and the probability of cylinder collision.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and in particular to a compressor start-up control method, device, compressor, and medium. Background Technology

[0002] Energy conservation has always been a focus and pursuit for businesses and consumers. For example, the cooling capacity of inverter refrigerators is adjustable, allowing for a better match between the refrigerator's cooling capacity and its load. Therefore, using an inverter refrigerator reduces energy consumption compared to using a traditional refrigerator.

[0003] However, the use of inverter refrigerators also has certain limitations. For example, during the compressor startup process, if the pressure difference between the suction pipe and the discharge pipe exceeds the preset threshold, the compressor's load torque will be too high, making it difficult to reach a balanced speed. This can easily lead to cylinder knocking and abnormal noise. Therefore, it is crucial to minimize the risk of suction and discharge pressure exceeding limits during compressor startup. Summary of the Invention

[0004] Therefore, it is necessary to provide a compressor start-up control method, device, compressor and medium to minimize the pressure difference between the intake pipe and the exhaust pipe from exceeding a preset threshold during compressor start-up, thereby reducing the occurrence of cylinder knocking noise.

[0005] A compressor start-up control method, the method comprising:

[0006] The compressor is started using a speed-open-loop method, and the current start-up time and current feedback speed of the compressor are obtained.

[0007] Under the premise that the current startup duration meets the conditions for maintaining startup and the current feedback speed does not meet the speed closed-loop conditions, the cumulative duration for which the current feedback speed exceeds the preset speed range is counted. If the cumulative duration is greater than the preset cumulative duration threshold, it is determined that the pressure difference between the compressor's suction pipe and discharge pipe is greater than the preset threshold, thereby driving the compressor to stop.

[0008] In one embodiment, after obtaining the current start-up duration and current feedback speed of the compressor, the method further includes:

[0009] If the current startup duration meets the conditions for maintaining startup and the current feedback speed does not meet the speed closed-loop conditions, and if the current feedback speed does not exceed the preset speed range, then return to the steps of obtaining the current startup duration and current feedback speed of the compressor and subsequent steps.

[0010] In one embodiment, after calculating the cumulative duration for which the current feedback speed exceeds the preset speed range, the method further includes:

[0011] If the cumulative duration is less than or equal to a preset cumulative duration threshold, then return to the step of obtaining the current start-up duration and current feedback speed of the compressor, and subsequent steps.

[0012] In one embodiment, after obtaining the current start-up duration and current feedback speed of the compressor, the method further includes:

[0013] Provided that the current startup duration meets the conditions for maintaining startup and the current feedback speed meets the conditions for speed closed-loop operation, the compressor is driven to switch into speed closed-loop operation.

[0014] In one embodiment, after obtaining the current start-up duration and current feedback speed of the compressor, the method further includes:

[0015] If the current startup duration does not meet the conditions for maintaining startup, the compressor will be shut down.

[0016] In one embodiment, the method further includes:

[0017] When the current startup duration is less than a preset startup duration threshold, it is determined that the current startup duration meets the conditions for maintaining startup.

[0018] When the current feedback speed is less than the preset equilibrium speed, it is determined that the current feedback speed does not meet the speed closed-loop condition.

[0019] In one embodiment, the preset rotational speed range is expressed as:

[0020] [n-Δn1, n+Δn1]

[0021] Where n is the current reference speed, and Δn1 is the preset speed deviation.

[0022] A compressor start-up control device, the device comprising:

[0023] The parameter acquisition module is used to start the compressor in a speed-open-loop manner and acquire the current start-up duration and current feedback speed of the compressor.

[0024] The control module is used to calculate the cumulative duration during which the current feedback speed exceeds a preset speed range, provided that the current startup duration meets the conditions for maintaining startup and the current feedback speed does not meet the speed closed-loop conditions. If the cumulative duration is greater than a preset cumulative duration threshold, the module determines that the pressure difference between the compressor's intake pipe and exhaust pipe is greater than a preset threshold and drives the compressor to stop.

[0025] A computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the compressor start-up control method described above.

[0026] A compressor includes a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of the compressor start-up control method described above.

[0027] This invention provides a compressor start-up control method, device, compressor, and medium. First, the compressor is started using a speed open-loop method, and the current start-up duration and current feedback speed are acquired. Under the premise that the current start-up duration meets the conditions for maintaining startup and the current feedback speed does not meet the speed closed-loop conditions, the cumulative duration for which the current feedback speed exceeds a preset speed range is calculated. If the cumulative duration exceeds a preset cumulative duration threshold, it is determined that the pressure difference between the compressor's suction pipe and discharge pipe is greater than the preset threshold, causing the compressor to stop. In other words, the cumulative time of speed fluctuation is used as the criterion for determining whether the pressure difference between the suction and discharge pipes exceeds the preset threshold. This criterion applies under the premise that the current start-up duration meets the conditions for maintaining startup and the current feedback speed does not meet the speed closed-loop conditions. By determining in advance that the pressure difference between the compressor's suction and discharge pipes exceeds the preset threshold and stopping the compressor, the compressor can be stopped before or immediately after noise occurs, effectively shortening the start-up attempt time and reducing noise levels and the probability of cylinder knocking. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] in:

[0030] Figure 1 This is a flowchart illustrating the compressor start-up control method in one embodiment;

[0031] Figure 2 This is a flowchart illustrating the control system in one embodiment;

[0032] Figure 3 This is a schematic diagram of a compressor controlling a variable frequency compressor using a field-oriented control algorithm in one embodiment;

[0033] Figure 4 A partial schematic diagram of a power electronic circuit in one embodiment.

[0034] Figure 5 This is a partial schematic diagram of a power electronic circuit in one embodiment;

[0035] Figure 6 This is a schematic diagram of a variable frequency compressor in one embodiment;

[0036] Figure 7 This is a schematic diagram illustrating the change of the speed of the variable frequency compressor over time during the open-loop acceleration phase and the closed-loop phase in one embodiment.

[0037] Figure 8 This is a first logic diagram of the compressor start-up control method;

[0038] Figure 9 This is a second logic diagram of the compressor start-up control method;

[0039] Figure 10 This is a schematic diagram of the compressor start-up control device in one embodiment;

[0040] Figure 11 This is a structural block diagram of a compressor in one embodiment. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] like Figure 1 As shown, Figure 1 This is a flowchart illustrating the compressor start-up control method in one embodiment. (Refer to...) Figure 2 The complete control system includes a main controller, a drive, and a variable frequency compressor. When the main controller sends a speed command to the drive, the drive controls the operation of the variable frequency compressor.

[0043] The driver consists of a microcontroller, a rectifier and voltage regulator circuit, a switching power supply, a power electronic circuit, a communication circuit, and a current sampling circuit. The rectifier and voltage regulator circuit converts AC power into unidirectional pulsating DC power and stabilizes the DC output voltage when the AC power supply voltage fluctuates or the load changes. The switching power supply controls the power supply to the microcontroller, power electronic circuit, and current sampling circuit. The current sampling circuit samples the current output from the rectifier and voltage regulator circuit and feeds it back to the microcontroller. The communication circuit transmits commands and feedback between the microcontroller and the main control machine. Figure 3 As shown, the microcontroller is used to control the variable frequency compressor using a field-oriented control (FOC) algorithm. Figure 4 and Figure 5 As shown, power electronic circuits include various switching devices used to generate various output waveforms, which are used to control the start and stop of the compressor.

[0044] Variable frequency compressors use brushless direct current motors (BLDCMs), overcoming the inherent shortcomings of brushed direct current motors by replacing the mechanical commutator with an electronic commutator. For example... Figure 6 As shown, a variable frequency compressor includes an intake pipe, an exhaust pipe, and a process pipe. During compressor startup, if the pressure difference between the intake and exhaust pipes is too large, the compressor's load torque will be too high, making it difficult to reach a balanced speed. This can easily lead to cylinder knocking and abnormal noise. Therefore, it is crucial to minimize the pressure difference between the intake and exhaust pipes from exceeding a preset threshold during compressor startup.

[0045] The compressor start-up control method provided in this embodiment includes the following steps:

[0046] S101 starts the compressor using a speed-open-loop method and obtains the compressor's current start-up duration and current feedback speed.

[0047] Among them, such as Figure 7 As shown, when the drive performs open-loop speed control (i.e., when the motor inside the compressor is in the open-loop acceleration phase), the motor speed will fluctuate significantly according to the load changes. In this step, after the compressor starts, the current start-up time t of the compressor is obtained at equal intervals. ′ and the current feedback speed n ′ If closed-loop speed control is then implemented (i.e., when the motor is in the closed-loop stage), the motor speed fluctuation will be significantly reduced. This shows that the dynamic response and accuracy of the motor in the open-loop acceleration stage are not as good as in the closed-loop stage, and the problem of cylinder knocking and abnormal noise is more likely to occur.

[0048] S102, under the premise that the current start-up duration meets the conditions for maintaining start-up and the current feedback speed does not meet the speed closed-loop conditions, the cumulative duration of the current feedback speed exceeding the preset speed range is counted. If the cumulative duration is greater than the preset cumulative duration threshold, it is determined that the pressure difference between the compressor's suction pipe and discharge pipe is greater than the preset threshold, and the compressor is driven to stop.

[0049] In a specific embodiment, first, it is determined that the current startup duration meets the condition for maintaining startup and the current feedback speed does not meet the speed closed-loop condition through the following steps: If the current startup duration is less than the preset startup duration threshold t2, it is determined that the current startup duration meets the condition for maintaining startup; if the current feedback speed is less than the preset balanced speed n2, it is determined that the current feedback speed does not meet the speed closed-loop condition. Of course, the startup duration threshold t2 and the balanced speed n2 here can be set according to actual requirements.

[0050] Specifically, referring to Figure 8 , Figure 8 which is the logic schematic diagram of this specific embodiment, first determine whether t ′ <t2. If the judgment result of t ′ <t2 is yes (Y), then determine whether n ′ >n2. If the judgment result of n ′ >n2 is no (N), then count the cumulative duration △t. That is, determine whether the current n' exceeds the rotational speed preset range [n - Δn1, n + Δn1], where n is the current reference rotational speed, referring to Figure 7 , n changes with time, and Δn1 is the preset rotational speed deviation, which is a fixed value. If the judgment result that n' exceeds the rotational speed preset range [n - Δn1, n + Δn1] is yes (Y), then count the cumulative duration △t. For example, when the judgment frequency of the compressor is 6000 Hz, △t is judged and accumulated once every 167 microseconds. Further, determine whether △t≥t0. If the judgment result of △t≥t0 is yes (Y), then it is determined that the pressure difference between the suction pipe and the discharge pipe of the compressor is greater than the preset threshold, driving the compressor to stop.

[0051] This is because the achievement speed of △t is positively correlated with the suction and discharge pressure difference of the compressor. The greater the suction and discharge pressure difference, the greater the speed fluctuation, and the shorter the achievement time of △t≥t0; conversely, the smaller the speed fluctuation, the longer the achievement time of △t. If △t≥t0 during the startup process, it is considered that the suction and discharge pressure difference is within the startup range, and this type of protection is not triggered at this time. It can be understood that the threshold t0 can be adjusted for different environments to achieve a balance between protection and successful startup.

[0052] It can be seen that the above startup control method of the compressor uses the time accumulation amount of speed fluctuation as the judgment condition for whether the pressure difference between the suction pipe and the discharge pipe is greater than the preset threshold. This judgment condition is applicable under the premise that the current startup duration meets the condition for maintaining startup and the current feedback speed does not meet the speed closed-loop condition. In this way, it is determined in advance that the pressure difference between the suction pipe and the discharge pipe of the compressor is greater than the preset threshold and the compressor is stopped, which can stop the compressor before or just when the noise occurs, effectively shortening the startup attempt time and reducing the noise level and the probability of cylinder collision.

[0053] Further, in a specific embodiment, after S101, the following steps are further executed: On the premise that the current startup duration meets the maintenance startup condition and the current feedback speed does not meet the speed closed-loop condition, if the current feedback speed does not exceed the speed preset range, return to execute the steps of obtaining the current startup duration and the current feedback speed of the compressor and subsequent steps.

[0054] As Figure 9 shown, that is, if the judgment result that n’ exceeds the speed preset range [n - Δn1, n + Δn1] is No (N), then the cumulative duration △t is not counted, and return to obtain the current startup duration t ′ and the current feedback speed n ′ , and execute subsequent steps, so as to realize loop judgment in the open-loop acceleration stage.

[0055] Further, in a specific embodiment, after S101, the following steps are further executed: If the cumulative duration is less than or equal to the preset cumulative duration threshold, return to execute the steps of obtaining the current startup duration and the current feedback speed of the compressor and subsequent steps.

[0056] As Figure 9 shown, that is, if the judgment result that △t≥t0 is No (N), then the compressor is not driven to stop, and return to obtain the current startup duration t ′ and the current feedback speed n ′ , and execute subsequent steps, so as to realize loop judgment in the open-loop acceleration stage.

[0057] Further, in a specific embodiment, after S101, the following steps are further executed: If the current startup duration does not meet the maintenance startup condition, drive the compressor to stop.

[0058] As Figure 9 shown, that is, if the judgment result that t ′ <t2 is No (N), drive the compressor to stop, in this case, it can avoid infinite loop for a long time.

[0059] Further, in a specific embodiment, after S101, the following steps are further executed: On the premise that the current startup duration meets the maintenance startup condition and the current feedback speed meets the speed closed-loop condition, drive the compressor to switch to speed closed-loop operation.

[0060] As Figure 9 shown, that is, if the judgment result that t ′ <t2 is Yes (Y), and n ′If the judgment result of >n2 is yes (Y), the compressor is directly driven to cut into speed closed-loop operation. This situation indicates that the condition of △t < t0 in the open-loop acceleration stage cannot be achieved, and it is considered that the suction and discharge pressure difference is within the starting range. At this time, the protection of premature shutdown is not triggered, and the compressor starts normally.

[0061] In one embodiment, as Figure 10 shown, a starting control device for a compressor is proposed. The device includes:

[0062] A parameter acquisition module 1001, configured to start the compressor based on a speed open-loop manner, and acquire the current starting duration and the current feedback speed of the compressor;

[0063] A control module 1002, configured to, on the premise that the current starting duration meets the condition for maintaining startup and the current feedback speed does not meet the speed closed-loop condition, count the cumulative duration during which the current feedback speed exceeds the preset speed range. If the cumulative duration is greater than the preset cumulative duration threshold, it is determined that the pressure difference between the suction pipe and the discharge pipe of the compressor is greater than the preset threshold, and the compressor is driven to stop.

[0064] Figure 11 shows the internal structure diagram of a compressor in one embodiment. As Figure 11 shown, the compressor includes a processor, a memory, and a serial communication interface (UART) connected through a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the compressor stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor can implement the starting control method of the compressor. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor can execute the starting control method of the compressor. Those skilled in the art can understand that Figure 11 the structure shown in

[0065] is only a block diagram of some structures related to the solution of this application, and does not constitute a limitation on the compressor to which the solution of this application is applied. The specific compressor may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements. A compressor includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the following steps are implemented: starting the compressor based on a speed open-loop manner, and acquiring the current starting duration and the current feedback speed of the compressor; on the premise that the current starting duration meets the condition for maintaining startup and the current feedback speed does not meet the speed closed-loop condition, counting the cumulative duration during which the current feedback speed exceeds the preset speed range. If the cumulative duration is greater than the preset cumulative duration threshold, it is determined that the pressure difference between the suction pipe and the discharge pipe of the compressor is greater than the preset threshold, and the compressor is driven to stop.

[0066] A computer-readable storage medium storing a computer program, which, when executed by a processor, performs the following steps: starting a compressor based on a speed open-loop method and acquiring the current start-up duration and current feedback speed of the compressor; under the premise that the current start-up duration meets the conditions for maintaining the start-up and the current feedback speed does not meet the conditions for speed closed-loop operation, calculating the cumulative duration for which the current feedback speed exceeds a preset speed range; if the cumulative duration is greater than a preset cumulative duration threshold, determining that the pressure difference between the compressor's suction pipe and discharge pipe is greater than a preset threshold, and driving the compressor to stop.

[0067] It should be noted that the above-mentioned compressor start-up control method, device, compressor, and computer-readable storage medium belong to the same general inventive concept, and the contents of the embodiments of the compressor start-up control method, device, compressor, and computer-readable storage medium are applicable to each other.

[0068] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The above embodiments merely illustrate several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A startup control method of a compressor, characterized by, The method comprises: starting the compressor in a speed open loop manner, and acquiring a current starting duration and a current feedback rotating speed of the compressor; under the premise that the current starting duration satisfies a starting maintaining condition and the current feedback rotating speed does not satisfy a speed closed loop condition, counting an accumulated duration in which the current feedback rotating speed exceeds a preset rotating speed range; if the accumulated duration is greater than a preset accumulated duration threshold, determining that a pressure difference between a suction pipe and a discharge pipe of the compressor is greater than a preset threshold, and driving the compressor to stop; The method further comprises: when the current starting duration is less than a preset starting duration threshold, determining that the current starting duration satisfies the starting maintaining condition; when the current feedback rotating speed is less than a preset balance rotating speed, determining that the current feedback rotating speed does not satisfy the speed closed loop condition.

2. The method of claim 1, wherein, After the current starting duration and the current feedback rotating speed of the compressor are acquired, the method further comprises: under the premise that the current starting duration satisfies the starting maintaining condition and the current feedback rotating speed does not satisfy the speed closed loop condition, if the current feedback rotating speed does not exceed the preset rotating speed range, returning to execute the step of acquiring the current starting duration and the current feedback rotating speed of the compressor and subsequent steps.

3. The method of claim 1, wherein, After the accumulated duration in which the current feedback rotating speed exceeds the preset rotating speed range is counted, the method further comprises: if the accumulated duration is less than or equal to the preset accumulated duration threshold, returning to execute the step of acquiring the current starting duration and the current feedback rotating speed of the compressor and subsequent steps.

4. The method of claim 1, wherein, After the current starting duration and the current feedback rotating speed of the compressor are acquired, the method further comprises: under the premise that the current starting duration satisfies the starting maintaining condition and the current feedback rotating speed satisfies the speed closed loop condition, driving the compressor to enter a speed closed loop operation.

5. The method of claim 1, wherein, After the current starting duration and the current feedback rotating speed of the compressor are acquired, the method further comprises: if the current starting duration does not satisfy the starting maintaining condition, driving the compressor to stop.

6. The method according to any one of claims 1 to 5, characterized in that, The preset rotating speed range is represented as: wherein, is the current reference rotational speed, is the preset rotational speed deviation.

7. A starting control device for a compressor, characterized by comprising: The device comprises: a parameter acquisition module configured to start the compressor in a speed open loop manner, and acquire a current starting duration and a current feedback rotating speed of the compressor; a control module configured to, under the premise that the current starting duration satisfies a starting maintaining condition and the current feedback rotating speed does not satisfy a speed closed loop condition, count an accumulated duration in which the current feedback rotating speed exceeds a preset rotating speed range, and if the accumulated duration is greater than a preset accumulated duration threshold, determine that a pressure difference between a suction pipe and a discharge pipe of the compressor is greater than a preset threshold, and drive the compressor to stop. The device is further configured to: when the current starting duration is less than a preset starting duration threshold, determine that the current starting duration satisfies the starting maintaining condition; when the current feedback rotating speed is less than a preset balance rotating speed, determine that the current feedback rotating speed does not satisfy the speed closed loop condition.

8. A computer readable storage medium storing a computer program, characterized in that, The computer program, when executed by a processor, causes the processor to perform the steps of the method according to any one of claims 1 to 6.

9. A compressor comprising a memory and a processor, characterized in that, The memory stores a computer program which, when executed by the processor, causes the processor to perform the steps of the method of any one of claims 1 to 6.

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