Compressor reverse phase protection determination and control method and device for air conditioning unit

Abstract

This disclosure presents a method and apparatus for determining and controlling reverse phase protection of an air conditioning unit's compressor. One specific implementation of the method includes: in response to generating a compressor start command, real-time acquisition of compressor operating parameters; joint determination of the acquired operating parameters; in response to generating a joint determination result; accumulation of the number of reverse phase occurrences based on the generated joint determination result; and in response to the accumulation of the number of reverse phase occurrences within a preset window reaching the protection trigger count, control the compressor to stop operating and enter a locked state. This implementation relates to the field of air conditioning unit technology, achieving precise protection of the compressor's physical hardware and providing key technical support for the reliable operation of air conditioning units under complex operating conditions.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the field of air conditioning unit technology, specifically to a method and apparatus for determining and controlling compressor reverse phase protection in air conditioning units. Background Technology

[0002] The compressor is the core power component of an air conditioning unit, and its normal operation depends on the correct correspondence between the power supply phase sequence and the compressor's wiring terminals. During the installation of air conditioning units, on-site power distribution modifications, or compressor replacement and repair, incorrect wiring by construction personnel or changes in the power supply phase sequence often result in the power supply phase sequence being reversed, causing the compressor to run in reverse. When it runs in reverse, the scroll plate cannot compress the refrigerant in the designed direction, and the normal pressure difference between the high and low pressure sides of the system cannot be established. Within minutes, this can lead to the scroll plate breaking, bearing wear, or motor burnout. The cost of replacing the damaged compressor and cleaning the system in a single incident can typically reach tens of thousands of yuan.

[0003] To prevent the aforementioned hazards, existing air conditioning units are generally equipped with compressor reverse phase protection. The current mainstream method for determining reverse phase protection involves setting a starting current threshold or instantaneous current threshold in the compressor drive board or the unit's main control board. When the actual detected starting current or instantaneous current value reaches or exceeds this set value, the unit is determined to have a reverse phase fault and triggers a protective shutdown. This judgment logic based on a single current threshold has the following technical problems: First, the current value is affected by various non-reverse phase factors, leading to false protection. Fluctuations in grid voltage and increased starting resistance due to residual pressure differences when the compressor restarts shortly after a shutdown can cause the starting current to deviate significantly from the normal value, easily triggering the threshold and causing the unit to misjudge reverse phase. In places with extremely high requirements for cooling continuity, such as data centers and hospital operating rooms, a single false shutdown can lead to uncontrolled ambient temperature and business losses of hundreds of thousands to millions of yuan due to server downtime. The compressor repeatedly experiences a cycle of "start-false judgment-shutdown," and each start and stop causes additional impact on the bearings and motor windings, accelerating component fatigue and aging. Second, raising the threshold to prevent false protection can lead to protection failure. In engineering, the current threshold is often set too high to allow for a margin, but when reverse phase actually occurs, the peak current may not reach the threshold. The compressor continues to operate in reverse without protection, and irreversible damage such as scroll plate breakage and bearing wear occurs, resulting in equipment replacement and system repair costs far exceeding normal maintenance costs. The core contradiction of using a single current threshold to determine reverse phase lies in the fact that the current may be too high to trigger a false alarm when the phase is not reversed, while the current may not be high enough to cause a missed alarm when the phase is reversed. The dilemma of "choosing a high or low threshold" cannot be solved simply by adjusting the threshold parameter. Thirdly, directly cutting off the power supply after detection lacks a safety buffer. Current technology typically cuts off the compressor's power supply directly after detecting reverse phase. The compressor's sudden stop while a high pressure differential still exists within the system further exacerbates the mechanical damage to the scroll plate and bearings due to rotational inertia impact and reverse leakage from the high pressure differential. The back electromotive force generated by the inverter's DC bus may also cause power device breakdown.

[0004] The information disclosed in this background section is only intended to enhance the understanding of the background of the present disclosure concept, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] The summary portion of this disclosure is intended to provide a brief overview of the concepts, which will be described in detail in the detailed description portion. This summary portion is not intended to identify key or essential features of the claimed technical solutions, nor is it intended to limit the scope of the claimed technical solutions.

[0006] Some embodiments of this disclosure provide image segmentation methods, apparatuses, electronic devices, and computer-readable media to address the technical problems mentioned in the background section above.

[0007] In a first aspect, some embodiments of this disclosure provide a method for determining and controlling reverse phase protection of a compressor in an air conditioning unit, comprising: in response to generating a compressor start command, real-time acquisition of compressor operating parameters, wherein the operating parameters include start time, start current, differential pressure, and speed; and joint determination of the acquired operating parameters, including: in response to the acquired start time being less than or equal to a start time limit threshold, generating a first determination result; in response to the acquired start current being greater than or equal to a start current threshold, generating a start current change value; and in response to the generated start current change value being less than or equal to a current increment threshold, generating... A second determination result is generated; in response to the collected differential pressure being less than or equal to the pressure build-up threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third determination result is generated; in response to the collected rotational speed being less than or equal to the rotational speed threshold, a fourth determination result is generated; in response to the generation of the first determination result, the second determination result, the third determination result, and the fourth determination result, a combined determination result is generated; based on the generated combined determination result, the number of reverse phase occurrences is accumulated; in response to the number of reverse phase occurrences accumulated within the preset window reaching the protection trigger count, the compressor is controlled to stop operating and enter a locked state.

[0008] Secondly, some embodiments of this disclosure provide a compressor reverse phase protection determination and control device for an air conditioning unit, comprising: a data acquisition unit configured to acquire compressor operating parameters in real time in response to generating a compressor start command, wherein the operating parameters include start time, start current, differential pressure, and speed; and a determination unit configured to jointly determine the acquired operating parameters, including: generating a first determination result in response to the acquired start time being less than or equal to a start time limit threshold; generating a start current change value in response to the acquired start current being greater than or equal to a start current threshold; and generating a second determination result in response to the generated start current change value being less than or equal to a current increment threshold. The system generates a second determination result; in response to the collected differential pressure being less than or equal to the pressure build-up threshold, it generates a differential pressure change value, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, it generates a third determination result; in response to the collected rotational speed being less than or equal to the rotational speed threshold, it generates a fourth determination result; in response to the generation of the first determination result, the second determination result, the third determination result, and the fourth determination result, it generates a combined determination result; the accumulation unit is configured to accumulate the number of reverse phase occurrences based on the generated combined determination result; the control unit is configured to control the compressor to stop operating and enter a locked state in response to the number of reverse phase occurrences accumulated within a preset window reaching the protection trigger count.

[0009] Thirdly, some embodiments of this disclosure provide an electronic device, including: one or more processors; and a storage device having one or more programs stored thereon, such that when the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any implementation of the first aspect.

[0010] Fourthly, some embodiments of this disclosure provide a computer-readable medium having a computer program stored thereon, wherein the program, when executed by a processor, implements the method as described in any implementation of the first aspect.

[0011] The method provided in the above embodiments of this disclosure has the following beneficial effects: by combining the judgment of multi-dimensional physical parameters and the anti-jitter confirmation mechanism of the counting window, accurate identification of reverse phase faults in air conditioning compressors is achieved, significantly reducing the false protection rate and false alarm rate of the single current threshold scheme under complex operating conditions, and effectively avoiding environmental temperature runaway caused by false shutdown and irreversible compressor damage caused by reverse operation. Specifically, in traditional reverse phase protection schemes (such as existing schemes that rely on a single current threshold), under non-reverse phase interference scenarios such as grid voltage fluctuations and system residual pressure difference, the peak starting current may rise abnormally due to non-reverse phase factors, triggering the threshold and causing the unit to shut down falsely; if the threshold is raised to avoid false protection, the peak current cannot reach the threshold when reverse phase actually occurs, and the compressor continues to operate in reverse without protection, resulting in irreversible damage such as scroll plate breakage and bearing wear. Based on this, the compressor reverse phase protection judgment method of the above embodiments of this disclosure firstly, in response to the generation of a compressor start command, collects the compressor's operating parameters in real time, including start time, start current, pressure difference, and speed. Therefore, synchronous monitoring of multiple key physical quantities is established immediately upon compressor startup, providing a parallel data foundation for subsequent multi-dimensional joint judgment. This ensures that judgments across different physical dimensions are based on the real-time status of the same startup process, avoiding misjudgments due to data asynchrony. Then, the collected operating parameters are jointly judged, including: generating a first judgment result in response to the collected startup time being less than or equal to a startup time limit threshold. Thus, startup time is used as the time dimension basis for reverse phase judgment; that is, reverse phase faults only occur during the startup phase. If the startup time has exceeded the time limit threshold required for normal startup, it indicates that the compressor has passed the startup transition period and entered the stable operation phase. At this point, any abnormalities in other parameters are no longer attributed to reverse phase, eliminating the possibility of false triggering under non-reverse phase operating conditions from a time dimension. Next, in response to the collected startup current being greater than or equal to a startup current threshold, a startup current change value is generated; and in response to the generated startup current change value being less than or equal to a current increment threshold, a second judgment result is generated. Therefore, the starting current change value is introduced as a dual criterion for current dimension judgment: it is necessary to check whether the current reaches the basic starting threshold, and whether the current shows a continuous upward trend after reaching the threshold and the current detection time. During normal startup, the current will continue to rise to a higher peak value after reaching the threshold, and the starting current change value is a large positive value; during reverse phase, the current cannot continue to rise after reaching the threshold or even decreases, and the change value is a small positive value, zero, or negative value. This mechanism enables the current dimension judgment to have a dual verification capability of "absolute value compliance + subsequent trend verification", avoiding single-point misjudgment caused by non-reverse phase factors (such as instantaneous fluctuations in the power grid). Next, in response to the collected differential pressure being less than or equal to the pressure build-up threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third judgment result is generated.Therefore, the differential pressure change value is introduced as a dual criterion for determining the differential pressure dimension: it is necessary to check whether the differential pressure has reached the basic pressure build-up threshold, and whether the differential pressure shows a continuous increasing trend after reaching the threshold and after a certain period of differential pressure monitoring. During normal startup, the differential pressure will continue to rise after reaching the threshold; during reverse phase, the compressor reverses and cannot effectively compress the refrigerant, and the differential pressure reaches a low value and cannot continue to increase or even decrease. The introduction of the differential pressure change value enables the determination of the differential pressure dimension to also have the dual verification capability of "absolute value compliance + subsequent trend verification", quantifying the typical physical characteristics of "slow pressure build-up or inability to continuously build up pressure" during reverse phase into comparable judgment conditions. Next, in response to the collected speed being less than or equal to the speed threshold, a fourth judgment result is generated. Thus, speed is used as the motion dimension criterion for reverse phase determination. During normal startup, the compressor speed should continuously rise to near the rated speed, while during reverse phase, it cannot reach the normal speed due to reversal or inability to build up load. The introduction of the speed threshold enables this method to have the ability to directly monitor the actual motion state of the compressor, without relying on indirect inference from current or pressure. Next, in response to the generation of the first, second, third, and fourth judgment results, a joint judgment result is generated. This logically converges the judgment results from four physical dimensions—time, current, differential pressure, and rotational speed—and triggers protection only when all four conditions are simultaneously met. This eliminates the risk of protection being triggered by interference with any single physical quantity, ensuring the judgment results are corroborated by multi-dimensional physical evidence. Then, based on the generated joint judgment result, the number of reverse phase occurrences is accumulated. Therefore, an anti-jitter counting mechanism is introduced, preventing shutdown from being triggered simply because a single joint judgment result is true; instead, the judgment results are accumulated to avoid false triggers due to momentary disturbances. Finally, in response to the accumulated number of reverse phase occurrences within a preset window reaching the protection trigger count, the compressor is controlled to stop operating and enter a locked state. Therefore, the shutdown action is only actually executed when the cumulative number of reverse phase judgments within the preset time window reaches the protection trigger threshold. This further filters out sporadic interference signals, ensuring that the shutdown decision is based on continuous and stable evidence of abnormal conditions. Simultaneously, it provides timely protection for the compressor's physical hardware (motor windings, bearings, scroll plate), preventing irreversible mechanical damage caused by reverse operation. Furthermore, because this method sets independent judgment conditions for four physical dimensions—time, current, differential pressure, and speed—and employs a dual verification mechanism combining the dynamic trend characteristic of "change value" with the static characteristic of "absolute value," it can effectively distinguish between single-parameter anomalies caused by non-reverse phase factors and global parameter coordinated anomalies caused by true reverse phase. It possesses an inherent "filtering" capability for non-reverse phase interference such as grid fluctuations, residual differential pressure startup, and ambient temperature changes.Meanwhile, through the logical convergence of "four conditions being met simultaneously" and the timing confirmation mechanism of "cumulative counting" and "preset window comparison," this method forms a complete closed loop in the time domain, current domain, pressure domain, and motion domain, from "signal acquisition" to "feature extraction" to "multi-dimensional verification" to "anti-jitter confirmation" and then to "physical execution." Thus, by combining the joint judgment of multiple physical quantities, the verification of dynamic change trends, and the anti-jitter confirmation of the counting window, it fundamentally solves the technical contradiction of "false protection and missed reporting" in a single current threshold scheme, achieving precise protection of the compressor's physical hardware and providing key technical support for the reliable operation of air conditioning units under complex operating conditions. Attached Figure Description

[0012] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. Throughout the drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and elements are not necessarily drawn to scale.

[0013] Figure 1 This is a flowchart of some embodiments of the compressor reverse phase protection determination and control method for air conditioning units according to the present disclosure; Figure 2 This is a schematic diagram of the structure of some embodiments of the compressor reverse phase protection determination and control device for air conditioning units according to the present disclosure; Figure 3 This is a schematic diagram of the structure of an electronic device suitable for implementing some embodiments of the present disclosure. Detailed Implementation

[0014] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0015] It should also be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other.

[0016] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0017] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0018] The names of messages or information exchanged between multiple devices in the embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of such messages or information.

[0019] This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] refer to Figure 1 The flowchart 100 illustrates some embodiments of a compressor reverse phase protection determination and control method for an air conditioning unit according to the present disclosure. The compressor reverse phase protection determination and control method for an air conditioning unit includes the following steps: Step 101: In response to the generation of the compressor start command, the operating parameters of the compressor are collected in real time.

[0021] In some embodiments, the executing entity of the above-described method for determining and controlling the reverse phase protection of an air conditioning unit (e.g., the main control board of the air conditioning unit) can, in response to generating a compressor start command, collect the compressor's operating parameters in real time. These operating parameters include start-up time, start-up current, differential pressure, and speed. The start-up time refers to the accumulated time of a timer within the main control board from the moment the compressor begins to rotate. In practice, the main control board monitors in real time whether the compressor rotor has started rotating using a speed sensor. When the main control board detects that the compressor speed has changed from zero to a value greater than zero, the timer within the main control board starts counting, and the accumulated time is the start-up time. The start-up current refers to the current value collected from the power supply line during the compressor motor's start-up process. In practice, the main control board collects the current signal on the compressor's power supply line in real time using a current sensor (e.g., a Hall effect current sensor or a current transformer). The current sensor converts the collected current signal into a voltage signal and outputs it to the analog-to-digital converter interface of the main control board. The main control board then converts the voltage signal into a digital current value through analog-to-digital conversion. The aforementioned pressure difference refers to the difference between the compressor's discharge port pressure and suction port pressure. This pressure difference is the difference between the compressor's high-pressure and low-pressure values. In practice, the main control board collects the compressor's discharge port pressure and suction port pressure using high-pressure and low-pressure sensors respectively. It converts the voltage signals output by the sensors into corresponding pressure values, then calculates the difference between the high-pressure and low-pressure values ​​to obtain the pressure difference. The pressure difference can also be directly collected using a pressure difference sensor. The aforementioned rotational speed refers to the number of revolutions the compressor rotor makes per unit time, usually expressed in revolutions per minute (rpm). In practice, the main control board collects the compressor's rotational speed using a speed sensor. This speed sensor can be a Hall effect sensor, mounted on the compressor stator frame, used to detect changes in the magnetic field generated by the permanent magnets on the compressor rotor. Each time the permanent magnets on the rotor pass the Hall effect sensor, the sensor outputs a pulse signal. The main control board captures these pulse signals and calculates the number of pulses per unit time to obtain the rotational speed. The rotational speed can also be estimated using a sensorless vector control algorithm. In practice, after generating the compressor start command, the main control board responds by starting to collect the aforementioned operating parameters in real time. For example, in cooling mode, when the indoor ambient temperature is higher than the user-set target temperature and the temperature difference is greater than or equal to 2 degrees Celsius, the main control board generates a compressor start command; in heating mode, when the indoor ambient temperature is lower than the user-set target temperature and the absolute value of the temperature difference is greater than or equal to 2 degrees Celsius, the main control board generates a compressor start command.For example, if the compressor starts at 0 seconds, the main control board responds to the generated compressor start command and begins to collect operating parameters in real time. At 0 seconds, it collects the compressor starting current as 90 amps, the differential pressure as 0.25 MPa, the speed as 0 rpm, and the start time as 0 seconds. At 2 seconds, it collects the starting current as 150 amps, the differential pressure as 0.62 MPa, the speed as 2100 rpm, and the start time as 2 seconds. At 3 seconds, it collects the starting current as 180 amps, the differential pressure as 0.60 MPa, the speed as 1800 rpm, and the start time as 3 seconds.

[0022] Optionally, the aforementioned implementing entity may also perform the following steps: Step 1: Obtain the indoor ambient temperature and the user-set target temperature. The indoor ambient temperature refers to the air temperature inside the room where the air conditioning unit is located, in degrees Celsius. In practice, an indoor temperature sensor (e.g., a negative temperature coefficient thermistor) is installed at the return air vent of the indoor unit of the air conditioner. It converts temperature changes into resistance changes. The main control board reads the voltage signal corresponding to this resistance value through a voltage divider circuit and an analog-to-digital converter interface, and converts the voltage signal into a temperature value, which is the indoor ambient temperature. The user-set target temperature refers to the temperature value that the user expects the air conditioning unit to maintain in the indoor environment, input via a remote control or wired controller, in degrees Celsius. In practice, the main control board receives the user-set command sent by the remote control or wired controller via an infrared receiving module or communication bus, and parses the user-set target temperature value from the command.

[0023] Step two: Based on the temperature difference between the acquired indoor ambient temperature and the target temperature, a compressor start command is generated. This temperature difference refers to the difference between the indoor ambient temperature and the user-set target temperature. In practice, after acquiring the indoor ambient temperature and the user-set target temperature, the main control board calculates the temperature difference by subtracting the target temperature from the indoor ambient temperature. Specifically, in cooling mode, when the indoor ambient temperature is higher than the user-set target temperature and the temperature difference is greater than or equal to 2 degrees Celsius, the main control board generates a compressor start command; in heating mode, when the indoor ambient temperature is lower than the user-set target temperature and the absolute value of the temperature difference is greater than or equal to 2 degrees Celsius, the main control board generates a compressor start command. For example, in cooling mode, if the user-set target temperature is 26 degrees Celsius and the indoor ambient temperature acquired by the main control board is 30 degrees Celsius, the temperature difference is 4 degrees Celsius, which is greater than 2 degrees Celsius, so the main control board generates a compressor start command. For example, in heating mode, if the user sets a target temperature of 20 degrees Celsius, and the main control board obtains an indoor ambient temperature of 16 degrees Celsius, the temperature difference is -4 degrees Celsius. Since the absolute value of the temperature difference is 4 degrees Celsius, which is greater than 2 degrees Celsius, the main control board generates a compressor start command. When the absolute value of the temperature difference is less than 2 degrees Celsius, for example, in cooling mode, the temperature difference between the indoor ambient temperature and the target temperature is only 1 degree Celsius, the main control board does not generate a compressor start command, and the compressor remains in standby mode.

[0024] Step 102: Perform a joint determination on the collected operating parameters.

[0025] In some embodiments, the aforementioned execution entity can perform joint determination on the collected operating parameters. This joint determination refers to comparing the start-up time, start-up current, differential pressure, and rotational speed collected in real-time in step 101 with their respective preset thresholds, generating corresponding determination results based on each comparison, and then logically converging all determination results. In practice, the main control board performs independent threshold comparisons on the collected start-up time, start-up current, differential pressure, and rotational speed, generating an independent determination result for each comparison. After all determination results are generated, the main control board then determines whether all determination results meet the conditions. If all conditions are met, it is considered a valid reverse-phase determination; if any one condition is not met, the determination is invalid.

[0026] Step 1021: In response to the collected startup time being less than or equal to the startup time limit threshold, a first determination result is generated.

[0027] In some embodiments, the aforementioned execution entity may generate a first determination result in response to the collected start-up time being less than or equal to a start-up time limit threshold. The start-up time limit threshold refers to the preset maximum allowable time required for the compressor to start rotating and complete startup, measured in seconds. The specific value of the start-up time limit threshold is pre-calibrated and stored in the non-volatile memory of the main control board based on the compressor model, start-up characteristics, and design parameters of the air conditioning unit. In practice, the main control board compares the start-up time collected in real-time in step 101 with the start-up time limit threshold. If the start-up time is less than or equal to the start-up time limit threshold, it indicates that the compressor is still within the start-up time limit, and the main control board generates a first determination result, which indicates that "the compressor is currently within the start-up time limit." If the start-up time is greater than the start-up time limit threshold, it indicates that the compressor has exceeded the normal start-up time limit, and the main control board does not generate a first determination result; the joint determination terminates directly. For example, the start-up time limit threshold for a certain model of compressor is calibrated to 5 seconds. When the main control board collects a start-up time of 3 seconds, since 3 seconds is less than 5 seconds, the main control board generates a first determination result. If the main control board collects a startup time of 7 seconds, since 7 seconds is greater than 5 seconds, the main control board will not generate the first judgment result, and the joint judgment will be terminated.

[0028] Step 1022: In response to the collected starting current being greater than or equal to the starting current threshold, a starting current change value is generated; and in response to the generated starting current change value being less than or equal to the current increment threshold, a second determination result is generated.

[0029] In some embodiments, the execution entity can generate a starting current change value in response to the collected starting current being greater than or equal to a starting current threshold, and generate a second determination result in response to the generated starting current change value being less than or equal to a current increment threshold. The starting current threshold refers to a preset minimum current value that should be reached during compressor startup, measured in amperes. The specific value of the starting current threshold is pre-calibrated based on the compressor's motor parameters, rated power, and startup characteristics and stored in the non-volatile memory of the main control board. The starting current change value refers to the difference between the current value and the starting current threshold after the starting current reaches the starting current threshold and after a current detection period, measured in amperes. This difference is used to characterize the trend of change in the starting current after reaching the threshold. The specific generation method of the starting current change value is shown in steps 10221 to 10223. The current increment threshold is a preset critical value used to determine whether the starting current change value is normal, measured in amperes. The specific value of the current increment threshold is pre-calibrated based on the normal starting current change characteristics of the compressor and stored in the non-volatile memory of the main control board. In practice, the main control board compares the generated starting current change value with the current increment threshold. If the starting current change value is less than or equal to the current increment threshold, it indicates that the starting current failed to generate sufficient increment after reaching the threshold, meaning the current did not exhibit the continuous upward trend expected during normal startup. The main control board generates a second judgment result, indicating "abnormal starting current change value." If the starting current change value is greater than the current increment threshold, it indicates that the starting current maintained a normal upward trend after reaching the threshold. The main control board does not generate a second judgment result, and this joint judgment terminates. For example, the starting current threshold for a certain model of compressor is 100 amps, and the current increment threshold is 5 amps. The main control board collects a starting current of 120 amps (reaching the starting current threshold), starts timing, and after the current detection time (e.g., 2 seconds), collects the current value of 135 amps. The calculated starting current change value is 135 minus 100, which equals 35 amps, greater than the current increment threshold of 5 amps. This indicates that the current is rising normally, and no second judgment result is generated. If the current value is 102 amps after the current detection period, the starting current change value is calculated as 102 minus 100 equals 2 amps, which is less than the current increment threshold of 5 amps. This indicates that the current has not risen normally, and the main control board generates a second judgment result.

[0030] In some optional implementations of certain embodiments, the aforementioned execution entity may generate the startup current change value through the following steps: Step 10221: In response to the collected starting current being greater than or equal to the aforementioned starting current threshold, timing begins. Here, timing refers to the duration accumulated by a timer inside the main control board from the moment the starting current reaches the starting current threshold. This timer is independent of the timer used to record the startup time in step 101. In practice, the main control board compares the collected starting current with the starting current threshold in real time. When the starting current first reaches or exceeds the starting current threshold, the main control board triggers the timer to start timing.

[0031] Step 10222: In response to the accumulated timing duration reaching the current detection duration, the current value is acquired. The aforementioned current detection duration refers to a preset waiting time, in seconds, between the start-up current reaching the start-up current threshold and the acquisition of the current value. The specific value of the current detection duration is pre-calibrated based on the compressor's start-up current rise rate and stored in the main control board's non-volatile memory. In practice, the main control board's timer continuously counts; when the accumulated timing duration reaches the current detection duration, the main control board acquires the current value at that moment through the current sensor; this current value is the current current value.

[0032] Step 10223: Generate the starting current change value based on the difference between the collected current value and the aforementioned starting current threshold. In practice, the main control board subtracts the starting current threshold from the current value collected in step 10222, and the calculated difference is the starting current change value. For example, the starting current threshold of a certain model of compressor is 100 amps, and the current detection time is 2 seconds. When the main control board collects a starting current of 120 amps, the starting current threshold is reached, and the main control board starts timing. After 2 seconds, the current value is collected as 135 amps. Subtracting the starting current threshold of 100 amps from the current current value of 135 amps yields a starting current change value of 35 amps. If, after 2 seconds, the current value is collected as 102 amps, subtracting the starting current threshold of 100 amps from the current current value of 102 amps yields a starting current change value of 2 amps.

[0033] Step 1023: In response to the collected differential pressure being less than or equal to the pressure establishment threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third determination result is generated.

[0034] In some embodiments, the aforementioned execution entity may generate a pressure difference change value in response to the collected pressure difference being less than or equal to the pressure build-up threshold, and generate a third determination result in response to the generated pressure difference change value being less than or equal to the pressure difference increment threshold. The pressure build-up threshold refers to the minimum pressure difference value that should be established between the high and low pressure values ​​during normal compressor startup, measured in megapascals (MPA). The specific value of the pressure build-up threshold is pre-calibrated based on the compressor's design parameters and the normal startup pressure build-up characteristics of the air conditioning unit's refrigeration system and stored in the non-volatile memory of the main control board. The pressure difference change value refers to the difference between the current pressure difference value and the pressure build-up threshold after the pressure difference reaches the pressure build-up threshold and after a pressure difference detection period, measured in megapascals (MPA). This difference is used to characterize the trend of pressure difference change after reaching the threshold. The specific generation method of the pressure difference change value is described in steps 10231 and 10233. The pressure difference increment threshold refers to a preset critical value used to determine whether the pressure difference change value is normal, measured in megapascals (MPA). The specific value of the differential pressure increment threshold is pre-calibrated based on the compressor's normal start-up pressure build-up characteristics and stored in the main control board's non-volatile memory. In practice, the main control board compares the generated differential pressure change value with the differential pressure increment threshold. If the differential pressure change value is less than or equal to the differential pressure increment threshold, it indicates that the differential pressure has not generated a sufficient increment after reaching the pressure build-up threshold, meaning the differential pressure has not shown the continuous upward trend that should be present during normal start-up. The main control board generates a third judgment result, which indicates "abnormal differential pressure change value." If the differential pressure change value is greater than the differential pressure increment threshold, it indicates that the differential pressure continues to rise normally after reaching the pressure build-up threshold. The main control board does not generate a third judgment result, and this joint judgment terminates. For example, the pressure build-up threshold of a certain model of compressor is 0.3 MPa, and the differential pressure increment threshold is 0.05 MPa. The main control board acquires a differential pressure of 0.35 MPa (reaching the pressure build-up threshold) and starts timing. After a differential pressure detection period (e.g., 3 seconds), the current differential pressure value is acquired to be 0.65 MPa. The calculated differential pressure change is 0.65 minus 0.3, which equals 0.35 MPa. This is greater than the differential pressure increment threshold of 0.05 MPa, indicating that the differential pressure is rising normally, and no third judgment result is generated. If, after the differential pressure detection period, the current differential pressure value is acquired to be 0.32 MPa, the calculated differential pressure change is 0.32 minus 0.3, which equals 0.02 MPa. This is less than the differential pressure increment threshold of 0.05 MPa, indicating that the differential pressure is not rising normally, and the main control board generates a third judgment result.

[0035] In some optional implementations of certain embodiments, the aforementioned execution entity may generate the differential pressure change value through the following steps: Step 10231: In response to the collected differential pressure being less than or equal to the aforementioned pressure build-up threshold, timing begins. Here, the aforementioned timing refers to the timer inside the main control board accumulating duration from the moment the differential pressure reaches the pressure build-up threshold. This timer is independent of the timer used to record the start-up time in step 101, and also independent of the timer used to record the current detection duration in step 10221. In practice, the main control board compares the collected differential pressure with the pressure build-up threshold in real time. When the differential pressure first reaches or exceeds the pressure build-up threshold, the main control board triggers the timer to start timing.

[0036] Step 10232: In response to the accumulated timing duration reaching the differential pressure detection duration, the current differential pressure value is acquired. The aforementioned differential pressure detection duration refers to a preset waiting time, in seconds, between the differential pressure reaching the pressure build-up threshold and the acquisition of the current differential pressure value. The specific value of the differential pressure detection duration is pre-calibrated based on the compressor's normal pressure build-up rate and stored in the main control board's non-volatile memory. In practice, the main control board's timer continuously counts. When the accumulated timing duration reaches the differential pressure detection duration, the main control board acquires the high-pressure value and low-pressure value at that moment through the high-pressure sensor and low-pressure sensor, respectively, and calculates the difference between the high-pressure value and the low-pressure value to obtain the current differential pressure value.

[0037] Step 10233: Generate the differential pressure change value based on the difference between the collected current differential pressure value and the aforementioned pressure build-up threshold. In practice, the main control board subtracts the pressure build-up threshold from the current differential pressure value collected in step 10232, and the calculated difference is the differential pressure change value. For example, the pressure build-up threshold of a certain model compressor is 0.3 MPa, and the differential pressure detection time is 3 seconds. When the main control board collects a differential pressure of 0.35 MPa, the pressure build-up threshold is reached, and the main control board starts timing. After 3 seconds, the current differential pressure value is collected as 0.65 MPa. Subtracting the pressure build-up threshold of 0.3 MPa from the current differential pressure value of 0.65 MPa yields a differential pressure change value of 0.35 MPa. If, after 3 seconds, the current differential pressure value is collected as 0.32 MPa, subtracting the pressure build-up threshold of 0.3 MPa from the current differential pressure value of 0.32 MPa yields a differential pressure change value of 0.02 MPa.

[0038] Step 1024: In response to the collected rotational speed being less than or equal to the rotational speed threshold, a fourth determination result is generated.

[0039] In some embodiments, the aforementioned execution entity may generate a fourth determination result in response to the collected rotational speed being less than or equal to a rotational speed threshold. The aforementioned rotational speed threshold refers to a preset minimum rotational speed value that the compressor should reach during normal startup, expressed in revolutions per minute (rpm). The specific value of the rotational speed threshold is pre-calibrated based on the compressor's design rated speed and normal startup characteristics and stored in the non-volatile memory of the main control board. In practice, the main control board compares the rotational speed collected in real-time in step 101 with the rotational speed threshold. If the rotational speed is less than or equal to the rotational speed threshold, it indicates that the compressor has failed to reach the minimum rotational speed required for normal operation during the startup phase, and the main control board generates a fourth determination result indicating "compressor speed abnormal." If the rotational speed is greater than the rotational speed threshold, it indicates that the compressor has reached or exceeded the minimum rotational speed required for normal startup, and the main control board does not generate a fourth determination result; the joint determination terminates. For example, if the speed threshold of a certain model compressor is calibrated to 1500 rpm, and the main control board collects the current speed as 1200 rpm, since 1200 is less than 1500, the main control board generates a fourth judgment result; if the main control board collects the current speed as 2100 rpm, since 2100 is greater than 1500, the main control board does not generate a fourth judgment result, and the joint judgment terminates.

[0040] Step 1025: In response to the generation of the first determination result, the second determination result, the third determination result, and the fourth determination result, a joint determination result is generated.

[0041] In some embodiments, the aforementioned execution entity can generate a joint judgment result in response to the generation of a first judgment result, a second judgment result, a third judgment result, and a fourth judgment result. The joint judgment result refers to a comprehensive judgment signal generated by logically aggregating the first, second, third, and fourth judgment results. This signal characterizes whether all four physical dimensions of the judgment conditions are met during the current compressor startup process. The joint judgment result is only generated when all four judgment results are generated. In practice, after the main control board completes its respective threshold comparison and generates judgment results in steps 1021, 1022, 1023, and 1024, it checks whether the first, second, third, and fourth judgment results have all been generated. If all four judgment results have been generated, the main control board generates a joint judgment result, indicating that a reverse phase judgment is successful. If any one of the judgment results is not generated, the main control board does not generate a joint judgment result, the reverse phase judgment is unsuccessful, and the main control board continues the cyclical process of real-time acquisition and joint judgment. For example, during a startup process, if the main control board detects a startup time of 3 seconds (less than the startup time threshold of 5 seconds) and generates a first judgment result; if the startup current reaches the startup current threshold and the current value collected during the current detection period is calculated to be 2 amps (less than the current increment threshold of 5 amps), a second judgment result is generated; if the differential pressure reaches the pressure build-up threshold and the current differential pressure value collected during the differential pressure detection period is calculated to be 0.02 MPa (less than the differential pressure increment threshold of 0.05 MPa), a third judgment result is generated; and if the rotational speed is 1200 rpm (less than the rotational speed threshold of 1500 rpm), a fourth judgment result is generated. Once all four judgment results are generated, the main control board generates a joint judgment result. If, among the four judgment results, the startup time, startup current change, and differential pressure change all meet the conditions, but the rotational speed is 2100 rpm (greater than the rotational speed threshold of 1500 rpm), and the fourth judgment result is not generated, then the main control board does not generate a joint judgment result, and the reverse phase judgment is invalid.

[0042] Step 103: Based on the generated joint determination result, accumulate the number of times the reverse phase occurs.

[0043] In some embodiments, the aforementioned execution entity can accumulate the number of reverse phase occurrences based on the generated joint determination result. The number of reverse phase occurrences refers to the total number of times the main control board has cumulatively determined a reverse phase since the compressor started. In practice, after generating the joint determination result, the main control board converts this valid determination into a reverse phase count. The reverse phase counter inside the main control board is incremented by one based on the current count value to obtain the updated reverse phase occurrence count, which is then stored in the main control board's non-volatile memory or random access memory. Simultaneously, the main control board also records the cumulative count within the current preset window according to its internal timer. For example, between the 0th and 10th seconds after the compressor starts, the main control board generates a joint determination result at the 3rd second, changing the reverse phase counter from 0 to 1; it generates another joint determination result at the 7th second, changing the reverse phase counter from 1 to 2; and it generates yet another joint determination result at the 12th second, changing the reverse phase counter from 2 to 3.

[0044] In the process of using the above technical solutions to solve the technical problems mentioned in the background technology, for the application scenario: in places with extremely high requirements for continuous cooling, such as data centers, hospital operating rooms, and subway stations, air conditioning units usually use variable frequency compressors and are in a state of continuous operation for a long time. The compressor starts and stops frequently and operates under high load. Once a reverse phase fault occurs and the unit needs to be stopped immediately for protection, the following technical problems often arise: the existing solutions usually directly cut off the power supply to the compressor after determining the reverse phase, causing the compressor to suddenly stop while there is still a high pressure difference inside the system. When a compressor stops abruptly while rotating at high speed, the enormous rotational inertial impact is directly transmitted to the scroll plate, crankshaft, and bearings. The root of the scroll teeth bears the impact load, causing fatigue cracks that gradually propagate. The bearing raceway surface forms indentations due to the impact, leading to stress concentration as the rollers rotate, ultimately causing the bearing to shatter. Simultaneously, the high-pressure refrigerant on both the high and low-pressure sides of the system leaks backward through the compressor's internal gaps to the low-pressure side, pushing the scroll plate to rotate in the opposite direction and generating abnormal impact noise, further exacerbating mechanical damage. For inverter-driven compressors, the sudden stop also causes a high-voltage back electromotive force to be generated on the inverter's DC bus, damaging power switching devices due to overvoltage breakdown. In data centers and similar locations, compressor damage can cost tens of thousands of yuan on average to replace the compressor and clean up the system. Furthermore, the interruption of cooling during maintenance can cause server rack temperatures to exceed limits, leading to server downtime. A single downtime can result in business losses ranging from hundreds of thousands to millions of yuan. Given the following requirements for this application scenario: when a compressor experiences a reverse phase fault, it must be shut down in a manner that minimizes the impact on the hardware, ensuring that the compressor's mechanical structure and the inverter's electrical components are not damaged by the sudden stop, and preventing business losses due to equipment failure and cooling interruption, we have decided to adopt the following solution: Step 104: In response to the number of reverse phase occurrences accumulated within the preset window reaching the protection trigger count, the compressor is controlled to stop operating and enter a locked state.

[0045] In some embodiments, the aforementioned execution entity may control the compressor to stop operating and enter a locked state in response to the cumulative number of reverse phase occurrences within a preset window reaching the protection trigger count. Here, the preset window refers to a pre-defined time length, used as a time window for counting the number of reverse phase occurrences, in seconds. The protection trigger count refers to a preset minimum number of reverse phase occurrences required to trigger the compressor shutdown within the preset window. In practice, the main control board records the current time each time a joint judgment result is generated and counts the cumulative number of reverse phase occurrences within the preset window time length. When the cumulative number of reverse phase occurrences within the preset window reaches the protection trigger count, the main control board initiates the shutdown control process. For example, if the preset window is 60 seconds and the protection trigger count is 3, the main control board initiates the shutdown control process when the cumulative number of reverse phase occurrences reaches 3 within the 60-second time window.

[0046] In some optional implementations of certain embodiments, the aforementioned execution entity may control the compressor to stop operating and enter a locked state in response to the cumulative number of reverse phase occurrences within a preset window reaching the protection trigger count through the following steps: Step 1041: In response to the cumulative number of reverse phase occurrences within the preset window reaching the protection trigger count, the current compressor speed and current differential pressure are acquired. The current speed refers to the actual compressor speed at the current moment, measured in revolutions per minute (rpm). The current differential pressure refers to the actual differential pressure of the compressor at the current moment, i.e., the difference between the high and low pressure values ​​at the current moment, measured in megapascals (MPa). In practice, after determining that the cumulative number of reverse phase occurrences within the preset window has reached the protection trigger count, the main control board immediately acquires the compressor's current speed through the speed sensor, and simultaneously acquires the current high and low pressure values ​​through the high-pressure and low-pressure sensors, calculating the difference between them to obtain the current differential pressure.

[0047] Step 1042: In response to the acquired current pressure difference being greater than zero, increase the output opening of the electronic expansion valve. The aforementioned electronic expansion valve refers to an electrically controlled regulating valve in the air conditioning unit's refrigeration system used to regulate refrigerant flow. Internally, a stepper motor drives the valve needle to move, adjusting the refrigerant mass flow rate by changing the flow cross-sectional area of ​​the valve orifice. The aforementioned output opening refers to the displacement of the electronic expansion valve's valve needle relative to the fully closed position, expressed as the number of steps of the stepper motor or as a percentage relative to the fully open position. In practice, the main control board compares the current pressure difference acquired in step 1041 with zero. If the current pressure difference is greater than zero, it indicates a positive pressure difference exists between the high-pressure and low-pressure sides of the system, requiring the release of this pressure difference to reduce the compressor's shutdown impact. The main control board outputs an opening increase signal to the electronic expansion valve. The stepper motor rotates forward according to this signal, driving the valve needle away from the valve seat, increasing the flow cross-sectional area of ​​the valve orifice, allowing refrigerant to flow from the high-pressure side to the low-pressure side, thus releasing the system pressure difference.

[0048] Step 1043: During the process of increasing the output opening of the electronic expansion valve, the real-time speed and real-time differential pressure of the compressor are continuously acquired. The real-time speed refers to the compressor's speed at various moments during the depressurization process, measured in revolutions per minute (rpm). The real-time differential pressure refers to the pressure difference of the compressor at various moments during the depressurization process, measured in megapascals (MPa). In practice, the main control board continuously increases the output opening of the electronic expansion valve, and during this process, the compressor's speed and differential pressure are continuously acquired at a preset sampling period (e.g., 100 milliseconds) to monitor the compressor's operating status changes in real time during the depressurization process.

[0049] Step 1044: In response to the acquired real-time rotational speed decreasing to a first safe rotational speed threshold and the acquired real-time differential pressure decreasing to a first safe differential pressure threshold, the compressor's operating frequency is reduced by the compressor's drive board according to a preset frequency reduction rate. The first safe rotational speed threshold is a preset minimum safe rotational speed value, measured in revolutions per minute (rpm), which is lower than the compressor's rated rotational speed but higher than zero. The first safe differential pressure threshold is a preset safe differential pressure value, measured in megapascals (MPA), which is lower than the differential pressure during normal compressor operation but higher than zero, indicating that the system differential pressure has been released to a level suitable for safe frequency reduction. The drive board refers to the compressor drive board, i.e., the power electronic device used to drive the compressor motor, which internally includes an inverter circuit and a drive control circuit, capable of changing the compressor's operating frequency according to the control signal output by the main control board. The preset frequency reduction rate refers to the preset rate at which the compressor's operating frequency decreases per unit time, measured in hertz per second (Hz). In practice, when the main control board detects that the real-time speed has decreased to the first safe speed threshold and the real-time differential pressure has decreased to the first safe differential pressure threshold, the main control board sends a frequency reduction command to the drive board. The drive board then gradually reduces the compressor's operating frequency according to a preset frequency reduction rate, allowing the compressor to smoothly decrease from its current speed. For example, if the first safe speed threshold is 1500 rpm, the first safe differential pressure threshold is 0.5 MPa, and the preset frequency reduction rate is 2 Hz / s, when the main control board detects that the real-time speed has decreased to 1500 rpm and the real-time differential pressure has decreased to 0.5 MPa, the main control board sends a frequency reduction command to the drive board, and the drive board reduces the compressor's operating frequency at a rate of 2 Hz / s.

[0050] Step 1045: During the process of reducing the operating frequency of the compressor, continuously acquire the updated real-time speed and updated real-time pressure difference of the compressor. The updated real-time speed refers to the compressor's speed value at various moments during the frequency reduction process, measured in revolutions per minute (rpm). The updated real-time pressure difference refers to the pressure difference value of the compressor at various moments during the frequency reduction process, measured in megapascals (MPA). In practice, as the drive board reduces the compressor's operating frequency according to the preset frequency reduction rate, the main control board continuously acquires the compressor's speed through a speed sensor and acquires and calculates the pressure difference through high-pressure and low-pressure sensors to monitor the changes in the compressor's speed and pressure difference in real time during the frequency reduction process.

[0051] Step 1046: In response to the acquired updated real-time rotational speed decreasing to zero and the acquired updated real-time differential pressure decreasing to the second safe differential pressure threshold, the power supply to the compressor is cut off via the compressor's drive board. The second safe differential pressure threshold is a preset safe differential pressure value, in megapascals (MPa), that allows for the disconnection of the compressor's power supply. This value is lower than the first safe differential pressure threshold and can be zero or close to zero, indicating that the system differential pressure has been largely released and that power-off will not cause mechanical shock when the compressor is completely stationary. In practice, when the main control board detects that the compressor's updated real-time rotational speed has decreased to zero (i.e., the compressor has completely stopped rotating) and the updated real-time differential pressure has decreased to the second safe differential pressure threshold, the main control board sends a power-off command to the drive board, which then cuts off the power supply to the compressor motor. For example, if the second safe differential pressure threshold is 0.05 MPa, when the main control board detects that the compressor speed has dropped to 0 rpm and the differential pressure has dropped to 0.05 MPa, the main control board sends a power-off command to the drive board, cutting off the compressor's power supply.

[0052] Step 1047: In response to the power supply to the compressor being cut off, the compressor is controlled to enter a mechanically locked state. This mechanically locked state refers to a state where the compressor rotor is fixed by a braking device or mechanical locking mechanism and cannot rotate freely. In practice, after confirming that the power supply to the compressor has been cut off, the main control board outputs a locking control signal to the compressor's mechanical locking device. The mechanical locking device activates, locking the compressor rotor in its current position to prevent the compressor from rotating unexpectedly under system pressure fluctuations or external forces, ensuring the compressor remains safely stationary.

[0053] Steps 1041 to 1047 of the above embodiments of this disclosure serve as an inventive point of this disclosure, solving the technical problem that "existing reverse phase protection schemes directly cut off the compressor power supply after determining reverse phase, causing the compressor to suddenly stop under high-speed rotation and high system pressure difference, thereby causing physical hardware damage such as scroll plate breakage, bearing impact damage and overvoltage breakdown of inverter power devices". Existing technologies for shutdown control after reverse phase detection have the following shortcomings: Firstly, after reverse phase detection, the compressor power supply is usually cut off directly, causing the compressor rotor to stop instantly at high speed. The huge rotational inertial impact is directly transmitted to the scroll plate, crankshaft, and bearings. The root of the scroll teeth bears the impact load, causing fatigue cracks that gradually propagate. The bearing raceway surface forms indentations due to the impact, leading to stress concentration when the rollers rotate, ultimately causing the bearing to break. Secondly, a high pressure difference still exists between the high and low pressure sides of the system at the moment of emergency stop. When the high-pressure refrigerant leaks backward through the internal gaps of the compressor to the low-pressure side, it pushes the scroll plate to rotate in the reverse direction, generating abnormal impact noise and further aggravating mechanical damage. Thirdly, for inverter-driven compressors, emergency stop also causes a high-voltage back electromotive force to be generated on the inverter's DC bus, damaging the power switching devices due to overvoltage breakdown and increasing user maintenance costs. Solving the above problems would allow the compressor to stop smoothly without mechanical impact or electrical damage after a reverse phase fault occurs, while maintaining a safe mechanical lock-in state, achieving dual protection for both the compressor's physical hardware and the inverter's electrical hardware. To achieve this effect, this disclosure proposes the following steps: Step 1041, in response to the accumulated number of reverse phase occurrences within a preset window reaching the protection trigger count, the current compressor speed and current differential pressure are acquired. Thus, the compressor's current motion and pressure states are acquired immediately upon triggering the shutdown process, providing physical parameter basis for subsequent staged shutdown control. This ensures that each control action is based on the compressor's current actual physical state rather than blindly executing fixed parameters, solving the problem of the emergency stop scheme lacking real-time compressor status awareness. Step 1042, in response to the acquired current differential pressure being greater than zero, the output opening of the electronic expansion valve is increased. Thus, by actively increasing the opening of the electronic expansion valve, the high-pressure refrigerant on the high-pressure side of the system is released to the low-pressure side through the throttling channel of the electronic expansion valve, actively reducing the system differential pressure. This active release of differential pressure ensures that the pressure between the high and low pressure sides of the system has been effectively reduced before the compressor's frequency reduction and power failure, solving the problem of secondary impact damage to the scroll plate caused by reverse leakage of high-pressure refrigerant through the compressor's internal gaps during emergency stop. Step 1043, during the process of increasing the output opening of the electronic expansion valve, the real-time compressor speed and real-time differential pressure are continuously acquired. Therefore, by establishing continuous monitoring of compressor speed and system pressure difference during the depressurization process, dynamic judgment basis is provided for the subsequent switch from the depressurization stage to the frequency reduction stage, solving the problem of lack of status feedback and inability to accurately judge the switching timing during the depressurization process.Step 1044: In response to the acquired real-time speed decreasing to the first safe speed threshold and the acquired real-time differential pressure decreasing to the first safe differential pressure threshold, the compressor's operating frequency is reduced by the compressor's drive board according to a preset frequency reduction rate. Thus, the compressor's frequency reduction and deceleration process begins once both the speed and differential pressure have decreased to the safe thresholds. The preset frequency reduction rate allows the compressor speed to decrease smoothly rather than abruptly, and the compressor rotor gradually transitions from high speed to low speed. Rotational inertia is gradually released through the frequency reduction process, and the scroll plate, crankshaft, and bearings no longer bear the high impact load during emergency stops. The inverter also does not generate high-voltage back electromotive force due to emergency stops, thus solving the problem of damage to the compressor hardware and inverter power devices caused by emergency stop impacts from both mechanical and electrical perspectives. Step 1045: During the process of reducing the compressor's operating frequency, the updated real-time speed and updated real-time differential pressure of the compressor are continuously acquired. Therefore, continuous monitoring of the compressor speed and system differential pressure is established during the frequency reduction process, providing dynamic judgment criteria for switching from the frequency reduction phase to the power-off phase, solving the problem of lack of status feedback and inability to accurately determine the timing of power-off during the frequency reduction process. Step 1046: In response to the acquired updated real-time rotational speed decreasing to zero and the acquired updated real-time differential pressure decreasing to the second safe differential pressure threshold, the power supply to the compressor is cut off via the compressor drive board. Therefore, the power-off action is only performed when both conditions are met simultaneously: the compressor rotor has completely stopped rotating and the system differential pressure has been substantially released. Zero rotational speed means all moving parts are completely stationary, and rotational inertia has been gradually released through the pressure relief and frequency reduction stages. At this point, power-off will not cause impact on any mechanical parts. A differential pressure reduced to the second safe differential pressure threshold means there is no high pressure differential within the system. After power-off, there is no risk of high-pressure refrigerant reverse flow, and the inverter does not generate back electromotive force when the compressor is stationary, thus solving the problem of mechanical impact and electrical damage caused by improper power-off timing. Step 1047: In response to the compressor power supply being cut off, the compressor is controlled to enter a mechanical lock state. Therefore, after the compressor is completely stationary and the power supply is cut off, the compressor rotor is fixed by the mechanical locking device, preventing the compressor from rotating unexpectedly under system differential pressure fluctuations or external vibrations, thus solving the safety hazard caused by the lack of physical locking after the compressor stops. In summary, steps 1041 to 1047 of this embodiment cooperate with each other, starting from the entire link of "state acquisition, differential pressure release, state monitoring, frequency reduction and deceleration, state monitoring, power failure confirmation to mechanical locking", and by constructing a three-stage hierarchical shutdown control framework of "first depressurization, then frequency reduction, and then power failure", a smooth and shock-free transition of the compressor from high-speed operation to complete standstill after a reverse phase fault is achieved.During the pressure relief phase, the high pressure differential backlash problem was resolved by actively opening the electronic expansion valve to release the system pressure difference. During the frequency reduction phase, the mechanical impact problem of emergency stop was resolved by smoothly releasing the rotational inertia through a preset frequency reduction rate. During the power-off phase, the problem of improper power-off timing was resolved by verifying the dual conditions of zero speed and zero pressure difference. During the locking phase, the problem of accidental rotation after shutdown was resolved by a mechanical locking device. Thus, the impact damage to the scroll plate, bearings, and crankshaft caused by emergency stop, as well as the electrical damage to the inverter power devices, were effectively eliminated. This achieved dual protection for the compressor's physical hardware and the inverter's electrical hardware, and to a certain extent, met the core requirement of safe and smooth shutdown of the air conditioning unit after a reverse phase fault.

[0054] In addressing the technical problems mentioned in the background section using the above-described technical solutions, considering the application scenario—in locations with extremely high requirements for continuous cooling, such as data centers, hospital operating rooms, and subway stations—air conditioning units typically operate continuously throughout the year. The electronic expansion valve in its refrigeration system, as a precision regulating component, has a stepper motor driving the valve needle to slide back and forth within the valve body for extended periods. Even minute impurities, lubricating oil carbon deposits, or mechanical wear of the valve body can cause the valve needle to jam. Once the electronic expansion valve jams during reverse-phase shutdown and pressure relief, it is often accompanied by the following technical issues. Problem: The main control board continuously sends an opening increase signal to the electronic expansion valve, but the valve needle does not actually move. The control command is disconnected from the actual state of the valve body, and the system pressure difference cannot be released through the electronic expansion valve. During the pressure relief phase, the main control board continuously waits for the pressure difference to decrease to the safe threshold, but because the pressure relief path has failed, the pressure difference can never reach the target, forming a dead loop of "pressure relief waiting," which indefinitely blocks subsequent frequency reduction and power-off steps. During this period, the compressor continues to run in reverse, and every second of reverse operation aggravates the wear of the scroll plate and bearings, ultimately leading to irreversible compressor damage due to missing the protection window. For critical locations such as data centers, a cooling interruption of several hours or even days caused by compressor failure will directly lead to excessive rack temperature and server downtime, causing incalculable business losses. To address the following requirements for this application scenario: the pressure relief path should have hardware redundancy and fault tolerance capabilities. When the electronic expansion valve becomes stuck, it should be quickly identified and automatically switched to the backup pressure relief path to ensure that the pressure relief process can be reliably completed under any circumstances, providing conditions for subsequent frequency reduction and power-off steps. We have decided to adopt the following solution: Optionally, during the process of increasing the output opening of the aforementioned electronic expansion valve, the aforementioned actuator may also perform the following steps: The first step is to obtain the initial opening value of the electronic expansion valve before it increases in opening, and then begin accumulating the jamming detection time. The initial opening value refers to the output opening value of the electronic expansion valve in a stable operating state before receiving the opening increase signal, expressed as the number of steps of the stepper motor or a percentage relative to the fully open position. The jamming detection time refers to the accumulated observation time, measured in seconds, from the start of the electronic expansion valve's opening increase action to determine whether jamming has occurred. In practice, while the main control board outputs the opening increase signal to the electronic expansion valve, it obtains the output opening value of the electronic expansion valve at the current moment through the valve position feedback sensor or by counting the drive pulses of the stepper motor; this value is the initial opening value. Simultaneously, the timer inside the main control board starts counting, and the accumulated time is the jamming detection time.

[0055] The second step is to obtain the real-time opening value of the aforementioned electronic expansion valve. This real-time opening value refers to the current output opening value of the electronic expansion valve during the process of increasing its opening. In practice, the main control board continuously acquires the output opening value of the electronic expansion valve at a preset sampling period (e.g., 50 milliseconds), and this value is the real-time opening value.

[0056] The third step is to generate the real-time opening change based on the acquired real-time opening value and the aforementioned initial opening value. This real-time opening change refers to the change in the real-time opening value relative to the initial opening value, used to characterize whether the electronic expansion valve produces actual displacement during the opening increase process. In practice, the main control board subtracts the initial opening value from the real-time opening value, and the calculated difference is the real-time opening change.

[0057] The fourth step involves generating a jamming judgment result in response to the generated real-time opening change being less than a preset opening change threshold and the accumulated jamming detection time reaching a preset jamming judgment time. The preset opening change threshold is a pre-defined minimum opening change threshold used to determine whether the electronic expansion valve has produced an effective opening change, expressed as a number of steps or a percentage. The preset jamming judgment time is a pre-defined maximum allowable observation time, in seconds, used to determine whether the electronic expansion valve has jammed. The jamming judgment result is a judgment signal indicating that the electronic expansion valve has jammed. In practice, the main control board compares the real-time opening change with the preset opening change threshold and the accumulated jamming detection time with the preset jamming judgment time. If the real-time opening change is less than the preset opening change threshold and the jamming detection time reaches the preset jamming judgment time, it indicates that the electronic expansion valve has failed to produce an effective opening change within the preset observation time, meaning the electronic expansion valve has jammed, and the main control board generates a jamming judgment result. For example, the preset opening change threshold is 10 steps, and the preset jamming detection time is 3 seconds. The main control board acquires an initial opening value of 100 steps and continuously acquires the real-time opening value during the electronic expansion valve's opening increase process. If the real-time opening value remains at 100 steps for 3 seconds, the real-time opening change is 0 steps, which is less than the preset opening change threshold of 10 steps, and the jamming detection time has reached 3 seconds, the main control board generates a jamming judgment result. If the main control board acquires a real-time opening value of 120 steps for 3 seconds, the real-time opening change is 20 steps, which is greater than the preset opening change threshold of 10 steps, it indicates that the electronic expansion valve has effectively responded to the opening increase command, and the main control board does not generate a jamming judgment result.

[0058] The fifth step involves obtaining the current status of the system bypass valve in response to the generated jamming determination result. The aforementioned system bypass valve refers to a backup pressure relief valve connected in parallel with the electronic expansion valve in the air conditioning unit's refrigeration system. Internally, it is driven by an electromagnetic coil, which opens the valve core when energized, forming a bypass flow path. This allows refrigerant to bypass the electronic expansion valve and flow from the high-pressure side to the low-pressure side, providing an alternative pressure relief path in case of electronic expansion valve failure or jamming. The aforementioned current status refers to the current state of the system bypass valve, including both closed and open states. In practice, after generating the jamming determination result, the main control board reads the current status of the system bypass valve through its status feedback signal line.

[0059] Step 6: In response to the acquired current state of the system bypass valve being closed, control the system bypass valve to open. The closed state refers to the state where the valve core of the system bypass valve completely seals the bypass flow path, preventing refrigerant from flowing through the bypass path. In practice, when the main control board detects that the current state of the system bypass valve is closed, it outputs an opening control signal to the solenoid coil of the system bypass valve. After the solenoid coil is energized, it generates electromagnetic force to drive the valve core to move, causing the valve core to leave the valve seat and opening the bypass flow path.

[0060] Step 7: In response to the successful opening or current open state of the system bypass valve, control the electronic expansion valve to maintain its current opening degree and keep the system bypass valve continuously open to jointly release the pressure difference. The aforementioned open state refers to the state where the valve core of the system bypass valve is completely away from the valve seat, the bypass flow path is fully open, and the refrigerant can flow freely through the bypass path. In practice, if the current state of the system bypass valve is already open (e.g., due to other faults or a previous operation), or if the main control board confirms successful opening of the system bypass valve through its status feedback signal, then the main control board controls the electronic expansion valve to maintain its current opening degree (stopping further increases in opening degree), while simultaneously controlling the system bypass valve to remain open. This allows the refrigerant to flow from the high-pressure side to the low-pressure side simultaneously through the current flow section of the electronic expansion valve and the bypass flow path of the system bypass valve, jointly releasing the system pressure difference.

[0061] Step 8: During the process of the electronic expansion valve and the system bypass valve jointly releasing the pressure difference, the real-time pressure difference of the compressor is obtained. The joint release of pressure difference refers to the process where the electronic expansion valve and the system bypass valve are simultaneously open, and the refrigerant flows from the high-pressure side to the low-pressure side through two parallel flow paths to reduce the system pressure difference. In practice, while the electronic expansion valve maintains its current opening and the system bypass valve remains open, the main control board continuously obtains the compressor's discharge port pressure and suction port pressure through the high-pressure sensor and low-pressure sensor, and calculates the difference between the two as the real-time pressure difference.

[0062] Step 9: In response to the acquired real-time differential pressure decreasing to the aforementioned first safe differential pressure threshold, the system bypass valve is controlled to close, and the opening of the electronic expansion valve is stopped from increasing. In practice, when the main control board detects that the real-time differential pressure has decreased to the first safe differential pressure threshold, it indicates that the system differential pressure has been released to a level where subsequent frequency reduction operations can be safely performed. The main control board outputs a closing control signal to the solenoid coil of the system bypass valve. After the solenoid coil is de-energized, the valve core returns to the valve seat under the action of the return spring, the bypass flow path is closed, and the system bypass valve returns to the closed state. At the same time, the main control board outputs a stop opening signal to the electronic expansion valve, keeping the electronic expansion valve in its current position. For example, the first safe differential pressure threshold is 0.5 MPa. During the joint depressurization process of the electronic expansion valve and the system bypass valve, the main control board continuously monitors the real-time differential pressure at 1.2 MPa, 0.9 MPa, and 0.6 MPa, eventually decreasing to 0.5 MPa. The main control board then controls the system bypass valve to close and stops increasing the opening of the electronic expansion valve. If the real-time differential pressure does not drop to 0.5 MPa during the depressurization process, the main control board will keep the system bypass valve open and the electronic expansion valve at its current opening position, and continue depressurizing until the conditions are met.

[0063] Steps one through nine of the above embodiments of this disclosure serve as an inventive point of this disclosure, solving the technical problem that "existing reverse phase protection schemes do not have valve body status monitoring and fault response mechanisms when releasing pressure through electronic expansion valves. When the electronic expansion valve becomes stuck, the pressure relief path fails, the system pressure difference cannot be released, the compressor continues to run in reverse, and subsequent frequency reduction and power-off steps cannot be executed, ultimately leading to irreversible damage to the compressor." Existing technologies for pressure relief control of electronic expansion valves have the following shortcomings: Firstly, as a precision regulating component in the refrigeration system, the electronic expansion valve's internal stepper motor drives the valve needle to slide within the valve body. After long-term operation, the valve needle and valve body may become stuck due to impurity accumulation, lubricating oil carbonization, or mechanical wear, preventing the valve needle from responding to the main control board's opening command and producing actual displacement. Secondly, existing pressure relief control schemes lack monitoring methods to determine whether the electronic expansion valve has produced actual opening changes. The main control board continuously sends opening increase signals, but the valve body does not respond, resulting in a disconnect between the control command and the actual state of the valve body, and the main control board cannot detect that the pressure relief path has failed. Furthermore, after the pressure relief path fails, the system pressure difference cannot be released, and the compressor continues to operate in reverse. Every second of reverse operation exacerbates the wear of the scroll plate and bearings, while the main control board is still waiting for the pressure difference to drop to the safe threshold, forming a vicious cycle of "pressure relief waiting," ultimately missing the protection window. Solving the above problems enables rapid fault identification and switching to a backup pressure relief path when the electronic expansion valve is stuck, ensuring reliable release of system differential pressure and providing conditions for subsequent frequency reduction and power-off steps, thus achieving hardware redundancy and fault tolerance of the pressure relief path. To achieve this, this disclosure proposes the following steps: First, obtain the initial opening value of the electronic expansion valve before its opening increases and begin accumulating the stuck detection time. Thus, while the electronic expansion valve begins its opening increase action, its initial position is recorded and timing is started, providing a benchmark for subsequent judgment of whether the electronic expansion valve has generated actual displacement, solving the problem of lacking quantitative criteria for whether the electronic expansion valve has truly responded to the opening command. Second, obtain the real-time opening value of the electronic expansion valve. Thus, during the opening increase process, the actual position of the electronic expansion valve is continuously acquired, providing real-time status input for calculating the opening change, solving the problem of lack of monitoring of the actual position of the electronic expansion valve during execution. Third, generate the real-time opening change based on the obtained real-time opening value and the initial opening value. Therefore, by quantifying the change in real-time opening value relative to the initial opening value, the actual displacement of the electronic expansion valve is transformed into a comparable mathematical quantity, solving the problem of the inability to quantitatively evaluate the opening response of the electronic expansion valve. The fourth step involves generating a jamming judgment result in response to the generated real-time opening change being less than a preset opening change threshold and the accumulated jamming detection time reaching a preset jamming judgment time. Thus, when the opening change remains below the effective change threshold for a preset observation period, the electronic expansion valve is judged to have jammed.The preset opening change threshold ensures that the judgment is based on effective displacement rather than noise signals, and the preset jamming judgment duration ensures that the judgment is based on continuous abnormal states rather than instantaneous fluctuations, solving the problem of the lack of clear and reliable judgment criteria for the jamming state of electronic expansion valves. The fifth step, in response to the generation of the jamming judgment result, obtains the current state of the system bypass valve. Therefore, after confirming the jamming failure of the electronic expansion valve, the current state of the backup pressure relief path is immediately obtained, providing a status basis for switching the pressure relief path, solving the problem of lack of awareness of the current state of the system bypass valve and the inability to determine whether it can be immediately put into use. The sixth step, in response to the obtained current state of the system bypass valve being closed, controls the opening of the aforementioned system bypass valve. Therefore, when the system bypass valve is in a usable closed state, the valve is actively opened to establish a backup pressure relief path, allowing the refrigerant to bypass the jammed electronic expansion valve and flow from the high-pressure side to the low-pressure side through the bypass flow path, solving the problem of lacking alternative pressure relief means after the pressure relief path fails due to the jamming of the electronic expansion valve. Step 7: In response to the successful opening or current open state of the system bypass valve, the electronic expansion valve is controlled to maintain its current opening, and the system bypass valve is kept open to jointly release the pressure difference. Thus, when the system bypass valve is in a pressure-relief state, the electronic expansion valve is maintained in its current position and no longer sends increasing signals to avoid a disconnect between the control command and the actual state. Simultaneously, the system bypass valve remains open, allowing the refrigerant to release the pressure difference through two parallel paths: the existing flow section of the electronic expansion valve and the bypass flow path of the system bypass valve. This solves the problem of insufficient pressure release flow from a single path leading to slow pressure difference release. Step 8: During the joint pressure difference release process of the electronic expansion valve and the system bypass valve, the real-time pressure difference of the compressor is acquired. Therefore, during the parallel pressure relief process of the two valves, the change in system pressure difference is continuously monitored, providing real-time status input for determining whether pressure relief is complete, solving the problem of lack of monitoring of pressure difference changes during the dual-valve pressure relief process. In the ninth step, in response to the acquired real-time differential pressure decreasing to the aforementioned first safe differential pressure threshold, the system bypass valve is closed, and the opening of the electronic expansion valve is stopped from increasing. Thus, when the system differential pressure has been released to a safe level, the backup pressure relief path is closed, allowing the refrigeration system to return to normal flow. Simultaneously, the signal to increase the opening of the electronic expansion valve is stopped, completing the pressure relief phase. This provides a clear completion signal for subsequent frequency reduction and power-off steps, resolving the problem of the system state not being reset after pressure relief, leading to a disconnect in subsequent control processes. In summary, steps one through nine of this embodiment cooperate with each other, starting from the entire chain of "position recording, status monitoring, quantitative evaluation, jamming judgment, status perception, valve opening, dual-valve parallel pressure relief, differential pressure monitoring, and pressure relief completion reset." By constructing a fault-tolerant pressure relief control framework with valve status monitoring, fault diagnosis, and backup path switching capabilities, hardware redundancy and fault tolerance of the pressure relief path are achieved.When the electronic expansion valve becomes stuck, the fault is determined by both the change in opening degree and the duration of the sticking detection. A backup pressure relief path is established by opening the system bypass valve. The electronic expansion valve maintains its current opening degree while the system bypass valve remains open, achieving parallel pressure relief with both valves. Differential pressure monitoring and pressure relief complete the reset process, ensuring seamless integration with the subsequent frequency reduction and power-off procedure. This effectively eliminates the risk of pressure relief failure caused by electronic expansion valve sticking, ensuring reliable release of system differential pressure under any circumstances. It provides fault-tolerant protection for the pressure relief stage in step 104's three-stage shutdown, achieving hardware redundancy in the pressure relief path and, to a certain extent, meeting the high reliability requirements of the air conditioning unit for safe shutdown after reverse phase failure under electronic expansion valve failure conditions.

[0064] The method provided in the above embodiments of this disclosure has the following beneficial effects: by combining the judgment of multi-dimensional physical parameters and the anti-jitter confirmation mechanism of the counting window, accurate identification of reverse phase faults in air conditioning compressors is achieved, significantly reducing the false protection rate and false alarm rate of the single current threshold scheme under complex operating conditions, and effectively avoiding environmental temperature runaway caused by false shutdown and irreversible compressor damage caused by reverse operation. Specifically, in traditional reverse phase protection schemes (such as existing schemes that rely on a single current threshold), under non-reverse phase interference scenarios such as grid voltage fluctuations and system residual pressure difference, the peak starting current may rise abnormally due to non-reverse phase factors, triggering the threshold and causing the unit to shut down falsely; if the threshold is raised to avoid false protection, the peak current cannot reach the threshold when reverse phase actually occurs, and the compressor continues to operate in reverse without protection, resulting in irreversible damage such as scroll plate breakage and bearing wear. Based on this, the compressor reverse phase protection judgment method of the above embodiments of this disclosure firstly, in response to the generation of a compressor start command, collects the compressor's operating parameters in real time, including start time, start current, pressure difference, and speed. Therefore, synchronous monitoring of multiple key physical quantities is established immediately upon compressor startup, providing a parallel data foundation for subsequent multi-dimensional joint judgment. This ensures that judgments across different physical dimensions are based on the real-time status of the same startup process, avoiding misjudgments due to data asynchrony. Then, the collected operating parameters are jointly judged, including: generating a first judgment result in response to the collected startup time being less than or equal to a startup time limit threshold. Thus, startup time is used as the time dimension basis for reverse phase judgment; that is, reverse phase faults only occur during the startup phase. If the startup time has exceeded the time limit threshold required for normal startup, it indicates that the compressor has passed the startup transition period and entered the stable operation phase. At this point, any abnormalities in other parameters are no longer attributed to reverse phase, eliminating the possibility of false triggering under non-reverse phase operating conditions from a time dimension. Next, in response to the collected startup current being greater than or equal to a startup current threshold, a startup current change value is generated; and in response to the generated startup current change value being less than or equal to a current increment threshold, a second judgment result is generated. Therefore, the starting current change value is introduced as a dual criterion for current dimension judgment: it is necessary to check whether the current reaches the basic starting threshold, and whether the current shows a continuous upward trend after reaching the threshold and the current detection time. During normal startup, the current will continue to rise to a higher peak value after reaching the threshold, and the starting current change value is a large positive value; during reverse phase, the current cannot continue to rise after reaching the threshold or even decreases, and the change value is a small positive value, zero, or negative value. This mechanism enables the current dimension judgment to have a dual verification capability of "absolute value compliance + subsequent trend verification", avoiding single-point misjudgment caused by non-reverse phase factors (such as instantaneous fluctuations in the power grid). Next, in response to the collected differential pressure being less than or equal to the pressure build-up threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third judgment result is generated.Therefore, the differential pressure change value is introduced as a dual criterion for determining the differential pressure dimension: it is necessary to check whether the differential pressure has reached the basic pressure build-up threshold, and whether the differential pressure shows a continuous increasing trend after reaching the threshold and after a certain period of differential pressure monitoring. During normal startup, the differential pressure will continue to rise after reaching the threshold; during reverse phase, the compressor reverses and cannot effectively compress the refrigerant, and the differential pressure reaches a low value and cannot continue to increase or even decrease. The introduction of the differential pressure change value enables the determination of the differential pressure dimension to also have the dual verification capability of "absolute value compliance + subsequent trend verification", quantifying the typical physical characteristics of "slow pressure build-up or inability to continuously build up pressure" during reverse phase into comparable judgment conditions. Next, in response to the collected speed being less than or equal to the speed threshold, a fourth judgment result is generated. Thus, speed is used as the motion dimension criterion for reverse phase determination. During normal startup, the compressor speed should continuously rise to near the rated speed, while during reverse phase, it cannot reach the normal speed due to reversal or inability to build up load. The introduction of the speed threshold enables this method to have the ability to directly monitor the actual motion state of the compressor, without relying on indirect inference from current or pressure. Next, in response to the generation of the first, second, third, and fourth judgment results, a joint judgment result is generated. This logically converges the judgment results from four physical dimensions—time, current, differential pressure, and rotational speed—and triggers protection only when all four conditions are simultaneously met. This eliminates the risk of protection being triggered by interference with any single physical quantity, ensuring the judgment results are corroborated by multi-dimensional physical evidence. Then, based on the generated joint judgment result, the number of reverse phase occurrences is accumulated. Therefore, an anti-jitter counting mechanism is introduced, preventing shutdown from being triggered simply because a single joint judgment result is true; instead, the judgment results are accumulated to avoid false triggers due to momentary disturbances. Finally, in response to the accumulated number of reverse phase occurrences within a preset window reaching the protection trigger count, the compressor is controlled to stop operating and enter a locked state. Therefore, the shutdown action is only actually executed when the cumulative number of reverse phase judgments within the preset time window reaches the protection trigger threshold. This further filters out sporadic interference signals, ensuring that the shutdown decision is based on continuous and stable evidence of abnormal conditions. Simultaneously, it provides timely protection for the compressor's physical hardware (motor windings, bearings, scroll plate), preventing irreversible mechanical damage caused by reverse operation. Furthermore, because this method sets independent judgment conditions for four physical dimensions—time, current, differential pressure, and speed—and employs a dual verification mechanism combining the dynamic trend characteristic of "change value" with the static characteristic of "absolute value," it can effectively distinguish between single-parameter anomalies caused by non-reverse phase factors and global parameter coordinated anomalies caused by true reverse phase. It possesses an inherent "filtering" capability for non-reverse phase interference such as grid fluctuations, residual differential pressure startup, and ambient temperature changes.Meanwhile, through the logical convergence of "four conditions being met simultaneously" and the timing confirmation mechanism of "cumulative counting" and "preset window comparison," this method forms a complete closed loop in the time domain, current domain, pressure domain, and motion domain, from "signal acquisition" to "feature extraction" to "multi-dimensional verification" to "anti-jitter confirmation" and then to "physical execution." Thus, by combining the joint judgment of multiple physical quantities, the verification of dynamic change trends, and the anti-jitter confirmation of the counting window, it fundamentally solves the technical contradiction of "false protection and missed reporting" in a single current threshold scheme, achieving precise protection of the compressor's physical hardware and providing key technical support for the reliable operation of air conditioning units under complex operating conditions.

[0065] Further reference Figure 2 As an implementation of the methods shown in the above figures, this disclosure provides some embodiments of a compressor reverse phase protection determination and control device for air conditioning units. These device embodiments are similar to... Figure 1 Corresponding to the method embodiments shown, the compressor reverse phase protection determination and control device for air conditioning units can be specifically applied to various electronic devices.

[0066] like Figure 2 As shown, a compressor reverse phase protection judgment and control device 200 for an air conditioning unit includes: a data acquisition unit 201, a judgment unit 202, an accumulation unit 203, and a control unit 204. The data acquisition unit 201 is configured to acquire compressor operating parameters in real time in response to the generation of a compressor start command. These operating parameters include start time, start current, differential pressure, and speed. The judgment unit 202 is configured to perform joint judgment on the acquired operating parameters, including: generating a first judgment result in response to the acquired start time being less than or equal to a start time threshold; generating a start current change value in response to the acquired start current being greater than or equal to a start current threshold; and generating a second judgment result in response to the generated start current change value being less than or equal to a current increment threshold; and generating a second judgment result in response to the acquired differential pressure being less than or equal to a start current threshold. The pressure difference change value is generated when the pressure build-up threshold is equal to the pressure difference threshold, and a third judgment result is generated when the generated pressure difference change value is less than or equal to the pressure difference increment threshold; a fourth judgment result is generated when the collected rotational speed is less than or equal to the rotational speed threshold; a combined judgment result is generated when the first, second, third, and fourth judgment results are generated; the accumulation unit 203 is configured to accumulate the number of reverse phase occurrences based on the generated combined judgment result; the control unit 204 is configured to control the compressor to stop operating and enter a locked state when the number of reverse phase occurrences accumulated within a preset window reaches the protection trigger count.

[0067] It is understandable that the units described in the compressor reverse phase protection determination and control device 200 for air conditioning units and the reference Figure 1The steps in the described method correspond accordingly. Therefore, the operations, features, and beneficial effects described above for the method also apply to the compressor reverse phase protection determination and control device 200 for air conditioning units and the units contained therein, and will not be repeated here.

[0068] The following is for reference. Figure 3 It shows a method suitable for implementing this disclosure. Figure 1 A schematic diagram of the structure of an electronic device 300 in some corresponding embodiments. Figure 3 The electronic device shown is merely an example and should not be construed as limiting the functionality or scope of the embodiments of this disclosure. Figure 3 As shown, the electronic device 300 may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 301, which can perform various appropriate actions and processes according to a program stored in a read-only memory 302 or a program loaded from a storage device 308 into a random access memory 303. The random access memory 303 also stores various programs and data required for the operation of the electronic device 300. The processing unit 301, the read-only memory 302, and the random access memory 303 are interconnected via a bus 304. An input / output interface 305 is also connected to the bus 304.

[0069] Typically, the following devices can be connected to the input / output interface 305: input devices 306 including, for example, a touchscreen, touchpad, keyboard, mouse, camera, microphone, accelerometer, gyroscope, etc.; output devices 307 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 308 including, for example, magnetic tape, hard disk, etc.; and communication devices 309. Communication device 309 allows electronic device 300 to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 3 An electronic device 300 with various devices is shown; however, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively. Figure 3 Each box shown can represent a device or multiple devices as needed.

[0070] In particular, according to some embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, some embodiments of this disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 309, or installed from a storage device 308, or installed from a read-only memory 302. When the computer program is executed by the processing device 301, it performs the functions defined in the methods of some embodiments of this disclosure.

[0071] It should be noted that, in some embodiments of this disclosure, the computer-readable medium described above may be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical fiber, a portable compact disk read-only memory, an optical storage device, a magnetic storage device, or any suitable combination thereof. In some embodiments of this disclosure, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In some embodiments of this disclosure, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0072] In some implementations, clients and servers can communicate using any currently known or future-developed network protocol such as HTTP (Hypertext Transfer Protocol) and can interconnect with digital data communication (e.g., communication networks) of any form or medium. Examples of communication networks include local area networks (“LANs”), wide area networks (“WANs”), the Internet (e.g., the Internet of Things), and peer-to-peer networks (e.g., ad hoc peer-to-peer networks), as well as any currently known or future-developed networks.

[0073] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device. The aforementioned computer-readable medium carries one or more programs that, when executed by the electronic device, cause the electronic device to: in response to generating a compressor start command, collect compressor operating parameters in real time, wherein the operating parameters include start time, start current, differential pressure, and speed; and perform joint determination on the collected operating parameters, including: in response to the collected start time being less than or equal to a start time threshold, generating a first determination result; in response to the collected start current being greater than or equal to a start current threshold, generating a start current change value; and in response to the generated start current change value being less than or equal to a current increment threshold... The system generates a second judgment result based on the collected differential pressure value. It generates a differential pressure change value when the collected differential pressure is less than or equal to the pressure build-up threshold, and a third judgment result when the generated differential pressure change value is less than or equal to the differential pressure increment threshold. It generates a fourth judgment result when the collected rotational speed is less than or equal to the rotational speed threshold. It generates a combined judgment result based on the generated combined judgment result. It accumulates the number of reverse phase occurrences based on the accumulated number of reverse phase occurrences within the preset window. When the accumulated number of reverse phase occurrences within the preset window reaches the protection trigger count, it controls the compressor to stop operating and enter a locked state.

[0074] Computer program code for performing operations of some embodiments of this disclosure can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0075] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0076] The units described in some embodiments of this disclosure can be implemented in software or in hardware. The described units can also be located in a processor.

[0077] The functions described above in this document can be performed at least in part by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), and so on.

[0078] The above description is merely a selection of preferred embodiments of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in the embodiments of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of this disclosure.

Claims

1. A method for determining and controlling reverse phase protection of an air conditioning unit's compressor, characterized in that, include: In response to the generation of a compressor start command, the compressor's operating parameters are collected in real time, including start time, start current, differential pressure, and speed. The collected operating parameters are jointly determined, including: If the collected startup time is less than or equal to the startup time limit threshold, a first judgment result is generated; In response to the collected starting current being greater than or equal to the starting current threshold, a starting current change value is generated, and in response to the generated starting current change value being less than or equal to the current increment threshold, a second determination result is generated. In response to the collected differential pressure being less than or equal to the pressure establishment threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third judgment result is generated. In response to the collected rotational speed being less than or equal to the rotational speed threshold, a fourth determination result is generated; In response to the generation of the first determination result, the second determination result, the third determination result, and the fourth determination result, a joint determination result is generated; Based on the generated joint decision results, the cumulative number of reverse phase occurrences is calculated; In response to the cumulative number of reverse phase occurrences within a preset window reaching the protection trigger count, the compressor is controlled to stop operating and enter a locked state.

2. The method according to claim 1, characterized in that, The pressure difference is the difference between the high pressure value and the low pressure value of the compressor.

3. The method according to claim 1, characterized in that, The generated start-up current change value includes: Timing begins when the collected starting current is greater than or equal to the starting current threshold. When the accumulated timing duration reaches the current detection duration, the current value is collected; The starting current change value is generated based on the difference between the current value collected and the starting current threshold.

4. The method according to claim 1, characterized in that, The generated differential pressure change value includes: Timing begins when the collected differential pressure is less than or equal to the pressure build-up threshold. When the accumulated timing reaches the differential pressure detection duration, the current differential pressure value is collected; The pressure difference change value is generated based on the difference between the current pressure difference value and the pressure establishment threshold.

5. The method according to claim 1, characterized in that, Before collecting the compressor's operating parameters, the following steps are also included: Obtain the indoor ambient temperature and the user-set target temperature; Based on the temperature difference between the obtained indoor ambient temperature and the target temperature, a compressor start command is generated.

6. A compressor reverse phase protection determination and control device for an air conditioning unit, characterized in that, include: The acquisition unit is configured to acquire the compressor's operating parameters in real time in response to the generation of a compressor start command, wherein the operating parameters include start time, start current, differential pressure and speed; The determination unit is configured to perform joint determination on the collected operating parameters, including: If the collected startup time is less than or equal to the startup time limit threshold, a first judgment result is generated; In response to the collected starting current being greater than or equal to the starting current threshold, a starting current change value is generated, and in response to the generated starting current change value being less than or equal to the current increment threshold, a second determination result is generated. In response to the collected differential pressure being less than or equal to the pressure establishment threshold, a differential pressure change value is generated, and in response to the generated differential pressure change value being less than or equal to the differential pressure increment threshold, a third judgment result is generated. In response to the collected rotational speed being less than or equal to the rotational speed threshold, a fourth determination result is generated; In response to the generation of the first determination result, the second determination result, the third determination result, and the fourth determination result, a joint determination result is generated; The accumulation unit is configured to accumulate the number of inverse occurrences based on the generated joint decision result; The control unit is configured to control the compressor to stop operating and enter a locked state in response to the cumulative number of reverse phase occurrences within a preset window reaching the protection trigger count.

7. An electronic device, characterized in that, include: One or more processors; Storage device, on which one or more programs are stored, When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-5.

8. A computer-readable medium, characterized in that, It stores a computer program that, when executed by a processor, implements the method as described in any one of claims 1-5.

Images