Superhigh-temperature heat pump starting cooperative control system and method based on multi-stage preheating

Abstract

The invention provides an ultrahigh-temperature heat pump starting cooperative control system and method based on multi-stage preheating, and the method comprises the steps: collecting temperature signals of the bottom of a compressor, the bottom of a gas-liquid separator and a water inlet of an evaporator, and comparing the temperature signals with a preset starting threshold value; if any temperature does not reach the standard, the corresponding heating device is controlled to conduct independent heating till the temperatures of the three points all reach the preset threshold value; based on the temperature of the bottom of the gas-liquid separator and the temperature rise rate thereof, judging whether the lubricating oil is activated from a high-viscosity state to a flowing state or not; under the lubricating oil activation state, the pre-position opening degree of the electronic expansion valve is calculated, and the electronic expansion valve is controlled to be opened to establish micro pressure difference; on the basis of the micro pressure difference and the oil return state, a collaborative ready index is constructed, and whether the system meets a starting condition or not is judged; if the starting condition is met, a starting mode of the compressor is selected according to the collaborative ready index, and starting operation is executed; and after completion, switching to a system normal operation mode, releasing the preheating device and recovering the standard control program.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of heat pumps, and particularly relates to a super-high-temperature heat pump starting cooperative control system and method based on multi-stage preheating. BACKGROUND

[0002] With the popularization and application of heat pump technology in high-temperature drying, heating and other industrial and civil fields, the selection of refrigerant directly affects the safety and reliability of the system. The existing heat pump system mostly uses R410A, R134a, R407C, R32, R290 and other medium and low temperature refrigerants. The boiling points of these working substances are generally lower than the normal temperature. When the system is shut down or on standby, the low-pressure side is mainly in gaseous or easily vaporized liquid state. When the compressor starts, the gasification can be realized by relying on the negative pressure generated by the body, so the starting is stable, the risk of liquid knock is small, and the oil film protection can be maintained. However, R1233zd is a low-GWP super-high-temperature refrigerant, and its boiling point is 18.26℃, which is in liquid state at normal temperature, which is significantly different from medium and low temperature refrigerants. When the system is shut down, there is usually liquid refrigerant in the bottom of the compressor cavity and the bottom of the gas-liquid separator, and the high-temperature lubricating oil matched with it has high viscosity and poor flowability at room temperature. If it is started directly at this time, the liquid refrigerant is easy to wash away the oil film and cause liquid knock and dry friction, which seriously affects the service life of the compressor. At the same time, the low-pressure side is not fully gasified, and the compressor is easy to trigger false alarm when pumping negative pressure, so the low-pressure switch is damaged. Because the evaporation side and the condensation side lack preheating during the starting stage, the system high and low pressure difference is formed slowly, the fluctuation is large at the initial stage of operation, and the compressor is in unstable working condition, which further accelerates the wear. More prominent is that the high-viscosity lubricating oil retained in the bottom of the gas-liquid separator at room temperature is difficult to return in time, resulting in lack of oil operation of the compressor at the initial stage of starting. The existing improvement measures such as simply increasing the crank heating belt or setting fixed preheating time are mostly solutions for low-boiling-point refrigerants, and cannot truly solve the problems of liquid knock, false alarm, slow pressure difference and oil shortage encountered by R1233zd system during the starting stage. SUMMARY

[0003] The purpose of the present application is to design a super-high-temperature heat pump starting cooperative control system and method based on multi-stage preheating, which can cover safety control from system preheating to the whole process of final running switching, and give solutions to the problems of liquid knock, false alarm, slow pressure difference and oil shortage which cannot be overcome by traditional strategies.

[0004] In order to achieve the above purpose, in the first aspect of the present application, a super-high-temperature heat pump starting cooperative control method based on multi-stage preheating is provided, which comprises: Collecting original temperature signals and comparing them with preset starting threshold values; if any temperature does not meet the standard, controlling the corresponding heating device to independently heat until the three temperatures all reach the preset threshold values; judging whether the lubricating oil is activated from high-viscosity state to flowable state based on the temperature and temperature rise rate at the bottom of the gas-liquid separator; When the lubricating oil is activated to flow state, a one-time pre-position opening degree of the electronic expansion valve is calculated and controlled to open to establish a micro pressure difference, and the micro pressure difference is estimated, and whether the oil return is completed is judged based on the micro pressure difference; Based on the micro pressure difference and the oil return state, a cooperative readiness index is constructed, and whether the start condition is met is judged based on the cooperative readiness index; If the start condition is met, the start mode of the compressor is selected according to the size of the cooperative readiness index, and the start operation is performed; after the start is completed, the system is switched to the normal operation mode, the preheating device is removed, and the standard control program is restored.

[0005] Further, the original temperature signal includes the temperature signal of the compressor bottom, the bottom of the gas-liquid separator and the inlet of the evaporator, the temperature signal of the compressor bottom is used to represent the actual metal shell temperature at the bottom of the compressor cavity, the temperature signal of the bottom of the gas-liquid separator is used to perceive the heat change of the metal area close to the lower part of the oil return hole, and the temperature signal of the inlet of the evaporator is used to measure the initial temperature of the hot water circulating system entering the evaporator.

[0006] Further, the step of judging whether the lubricating oil is activated to flow state includes: calculating the temperature rising rate of the bottom of the gas-liquid separator in unit time; if the temperature reaches a threshold value and the temperature rising rate is lower than a set threshold value, it is determined that the lubricating oil has been activated to flow state.

[0007] Further, a thermal imbalance suppression term is introduced in the calculation of the pre-position opening degree of the electronic expansion valve, which is used to suppress the flow mutation caused by the temperature difference between the compressor and the gas-liquid separator.

[0008] Further, the establishment of the micro pressure difference depends on the geometric height difference between the liquid accumulator and the gas-liquid separator and the pipeline resistance, and is estimated by a calibration coefficient.

[0009] Further, the construction of the cooperative readiness index includes: weighting and synthesizing the micro pressure difference amplitude, the oil return state and the pressure difference change rate; if the index continuously exceeds a threshold value and remains for a certain time, it is determined that the start condition is met.

[0010] Further, the start mode includes standard start and delay soft start, and the start mode is selected according to the ratio of the cooperative readiness index to the threshold value.

[0011] Further, if the ratio is lower than 1, the delay soft start mode is adopted, and the compressor voltage is gradually increased; if the ratio is equal to or higher than 1, the direct standard start mode is adopted.

[0012] Further, the method does not rely on additional pressure or flow sensors before the start of the compressor, and only realizes the whole process closed loop control through temperature signal and valve control.

[0013] In a second aspect of the application, a multi-stage preheating-based ultra-high temperature heat pump startup cooperative control system is provided, the system comprising: A partition preheating module is configured to collect original temperature signals and compare them with preset startup threshold values; if any temperature fails to meet the threshold, the corresponding heating device is controlled to independently heat until all three temperatures reach the preset threshold values; based on the temperature at the bottom of the gas-liquid separator and the temperature rise rate, it is determined whether the lubricating oil is activated from a high viscosity state to a flow state; An oil return state module is configured to calculate a one-time pre-position opening degree of the electronic expansion valve when the lubricating oil is activated to the flow state, control the opening of the electronic expansion valve to establish a micro pressure difference, and estimate the size of the micro pressure difference, based on which it is determined whether the oil return is completed; A cooperative decision module is configured to construct a cooperative readiness index based on the micro pressure difference and the oil return state, and determine whether the system meets the startup condition; An execution module is configured to select a startup mode of the compressor according to the size of the cooperative readiness index if the startup condition is met, and perform a startup operation; after the startup is completed, the system is switched to a normal operation mode, the preheating device is removed, and the standard control program is restored.

[0014] The application has at least the following beneficial technical effects: To solve the above problems, the application provides a multi-stage preheating-based ultra-high temperature heat pump startup cooperative control system and method, which collects and preheats multiple temperatures at the bottom of the compressor, the bottom of the gas-liquid separator and the evaporator inlet, and determines whether the oil film is truly converted from a high viscosity state to a flow state by combining the temperature rise rate, so that a more real oil film activation state is obtained before startup. Based on the premise of oil film activation, the controller calculates a one-time micro-opening pre-position opening degree of the electronic expansion valve, introduces a thermal imbalance suppression term to avoid sudden surges, and uses the height difference between the liquid accumulator and the gas-liquid separator to establish a slight pressure difference to complete the induced return flow of the lubricating oil without starting the compressor. Then, by constructing a cooperative readiness index containing the pressure difference amplitude, the oil return state and its stability term, a comprehensive determination across the heat, pressure and oil fields is realized to ensure that the startup signal is only sent when all conditions are stable. Finally, the cooperative index is combined with the startup execution mode to introduce a startup execution factor to determine the actual power-on mode of the compressor, to adopt a delay or soft startup when the conditions just meet the threshold, to directly enter the standard startup when the margin is sufficient, and to gradually restore the system operation parameters during the switching process, so that the entire heat pump system smoothly enters a stable working condition. This innovative scheme realizes a full-process closed-loop control of multi-point preheating, oil film activation determination, oil return channel establishment, cooperative state determination and execution switching without changing the hardware structure of the main machine, truly fits the physical property characteristics of R1233zd working medium, and significantly improves the safety and reliability of the system startup. BRIEF DESCRIPTION OF DRAWINGS

[0015] The present invention is further described with reference to the accompanying drawings. However, the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative effort.

[0016] Figure 1 This is a flow chart of the ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating of the present invention.

[0017] Figure 2 This is a framework diagram of the ultra-high temperature heat pump startup coordinated control system based on multi-stage preheating of the present invention. DETAILED DESCRIPTION

[0018] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0019] In one or more embodiments, Figure 1 As shown, a method for coordinated control of ultra-high temperature heat pump startup based on multi-stage preheating is disclosed, the method comprising the following steps: S1: Collects the original temperature signal and compares it with the preset start threshold. If any temperature does not meet the standard, the corresponding heating device is controlled to independently heat until the temperatures of all three points reach the preset threshold. Based on the temperature and temperature rise rate at the bottom of the gas-liquid separator, it is determined whether the lubricating oil has been activated from a highly viscous state to a fluid state. Specifically, when the R1233zd heat pump system is not in operation, the refrigerant is still liquid at room temperature, which can easily form a liquid stagnation layer at the bottom of the compressor, in the gas-liquid separator, and on one side of the evaporator. Furthermore, the lubricating oil used is highly viscous and has poor fluidity at room temperature. Therefore, a "multi-point thermal activation" operation must be completed before the compressor is started. The core goal of this operation is to ensure that three key nodes of the system—the compressor cavity (to prevent liquid hammer), the bottom of the gas-liquid separator (to clear the oil return path), and the evaporator water inlet (to improve initial heat exchange capacity)—have reached independent thermal stability. It also determines whether the lubricating oil has been activated from a highly viscous state to a flowable state, providing assurance for oil return control and pressure differential establishment in subsequent operations.

[0020] The original input of this step is three temperature sensor signals, namely the thermocouple installed on the bottom shell of the compressor , used to collect the actual metal shell temperature at the bottom of the compressor cavity; the thermocouple installed on the bottom side wall of the gas-liquid separator , used to sense thermal changes in the metal area just below the oil return hole; and the thermistor attached to the copper tube at the C port (water inlet) of the evaporator , for measuring the initial temperature of the hot water circulating system into the evaporator. All sensor signals are merged into the main control board through the A / D module, and the numerical format is unified to 32-bit floating point, with an update period of once per second. To ensure stable temperature response, each reading is filtered by a 3-second moving average filter to reduce external interference errors.

[0021] The control mainboard first compares , and with the preset start threshold one by one. The bottom of the compressor needs to reach ; the bottom of the gas-liquid separator needs to reach ; the evaporator inlet temperature needs to reach . If any temperature does not meet the standard, the system maintains the "preheating" state, and controls the corresponding heating unit according to the unqualified item: when does not meet the standard, the heating belt one is powered on to heat the bottom of the compressor; does not meet the standard, the heating belt two works; does not meet the standard, the linked water pump and the electric heating element in the water tank send hot water into the evaporator to raise the inlet water temperature. It is worth noting that the heating methods of the three areas are independently operated and do not interfere with each other, and are controlled by the main control program to close or open according to the real-time temperature.

[0022] In the process of determining whether the lubricating oil at the bottom of the gas-liquid separator has fluidity, it is not enough to rely only on the absolute value of the temperature . Because in the structural layer, the oil often stays near the bottom oil return hole, and the heat conduction has hysteresis, if just meets the standard, but the oil layer has not completed the heat penetration, it may appear that the temperature meets the standard but the oil is not activated. Therefore, this step introduces the temperature rise rate criterion to assist in determining whether the oil film is truly activated.

[0023] ; where represents the temperature rise rate per unit time at the bottom of the gas-liquid separator, is the moving average value of after processing at the current time, is the rate calculation time window, set to 30 seconds.

[0024] Combining and , the oil film activation state variable is defined by the following conditions: ; where is a Boolean variable, indicating whether the lubricating oil has been converted from high viscosity state to flow state; is the rate threshold of oil film activation, and the set value is 0.03.

[0025] Specifically, in the present embodiment, when the current has risen to 49.8, and the growth rate of the temperature within 10 seconds is 0.4, it is determined that the oil film has been activated; if the temperature rise rate is still greater than 0.05, it is considered that the oil layer has not been sufficiently heated, and needs to continue heating. , the control system enters the next stage of operation. , it is considered that the oil layer has been activated; if the temperature rise rate is still greater than 0.05, it is considered that the oil layer has not been sufficiently heated, and needs to continue heating.

[0026] Finally, when , , and , the control system enters the next stage of operation.

[0027] S2: When the lubricating oil is activated to the flow state, the one-time pre-position opening degree of the electronic expansion valve is calculated, and the opening is controlled to establish a micro pressure difference, and the micro pressure difference is estimated, and it is judged whether the oil return is completed based on the micro pressure difference; Specifically, under the premise that the compressor is not started, the thermal standard of step one and the oil film activation result are the only trigger conditions, the small pre-position of the electronic expansion valve (EEV) and the system geometric liquid level difference are used to build a low disturbance channel and a controllable micro pressure difference, so that the lubricating oil at the bottom of the gas-liquid separator returns to the compressor cavity along the return hole through the tee, and the oil film regression before starting is completed. The particularity here is that R1233zd is liquid at room temperature, and the oil is high viscosity. If the channel and the micro pressure difference are lacking, the oil is easy to stay at the bottom of the separator; and early large opening degree is easy to cause sudden change and false report on the low pressure side.

[0028] After the control mainboard confirms that , , all reach the corresponding threshold value and , the one-time pre-position opening degree is calculated, and the opening degree is written into the step drive chip of EEV1 and EEV2 (the pulse count is converted according to the valve full stroke percentage, and after writing, it is maintained and not adjusted again). The calculation of the pre-position opening degree introduces a "thermal imbalance suppression term" to automatically converge the opening degree when the temperature has reached the standard but there is still a difference between the temperatures of the two key cavities, so as to avoid sudden surge when the temperature is not completely balanced. The formula is as follows: ; Among them, is the opening degree ratio of the one-time pre-position of the EEV (dimensionless value with full stroke as 1); is used to directly set the opening degree to zero when the oil film is not activated; The three-point temperature threshold constants are set at the factory; the three ratios are normalized according to the thresholds to ensure numerical consistency; Constrain the opening degree not to exceed the "thermal completion degree" of the weakest link; difference item is the thermal imbalance suppression term, the coefficient To solidify the penalty weight, its function is to suppress the excessively fast channel opening when there is a residual temperature difference between the compressor cavity and the separator cavity. , then the three ratios are approximately , taking the minimum value of approximately The difference is approximately , corresponding to the penalty ,get ,like Then arm according to this value.

[0029] EEV Press After pre-positioning, a micro-pressure difference that can be determined is established under low disturbance by relying on the equivalent geometric height of the reservoir relative to the separator and the pipeline resistance. To facilitate engineering implementation, the geometric-operating coefficient synthesized by bench calibration is used. (Convert the liquid density, gravity, equivalent height, and minimum flow cross-sectional resistance into a single coefficient and store it in the mainboard non-volatile memory) to estimate the size of the micro-pressure difference in a one-time manner: ; in, is the estimated channel pressure value (the calculation dimension has been normalized by coefficient integration); It is a factory calibration constant obtained by fitting the static level difference and the minimum opening flow rate. The control board starts timing after writing the opening, maintaining the EEV pre-position and system static time window (for example, a fixed value of 60); if the low-pressure side protection is not triggered within the time window, and If the value is not less than the solidification threshold (for example, a fixed value of 150), the channel is considered established and has sufficient traction to allow the retained oil to return along the oil return hole, the tee, the return air line, and finally the compressor cavity. In actual implementation, no additional pressure or flow sensors are required, avoiding structural modifications. The valve opening command is written once, and this step ends when the time window expires.

[0030] S3: constructing a collaborative readiness index based on the micro-pressure difference and the oil return state, and determining whether a startup condition is met based on the collaborative readiness index; Specifically, this step is executed after the first two steps are completed. The goal is to make a unified judgment on whether the oil film reflux is completed and whether the micro-pressure difference is effectively established, and convert the result into the start-up release instruction of the compressor. Different from the traditional logic that only relies on the temperature reaching the standard, the output of step 2 is converted into and As the only decision input, combined with a timing retention mechanism and a special regularization term, it ensures that the pressure difference is not formed by instantaneous pulse, but truly and stably exists, while confirming that the oil film has returned to the compressor cavity smoothly. The significance of doing so is that the R1233zd refrigerant in this embodiment is liquid at room temperature and has high oil viscosity. If only the temperature is considered, there is a risk of false pressure difference or oil film not returning before starting.

[0031] The control mainboard receives With , does not immediately issue a start command, but first constructs a cooperative readiness index to judge the stability of the micro-pressure difference and oil return state. This index not only considers The amplitude, but also introduces a change rate suppression term to avoid the system being misjudged as meeting the conditions due to pressure transients. The formula is as follows: ; Where, is the cooperative readiness index; is the minimum effective pressure difference threshold (calibrated in bench tests, such as a fixed value of 150); , , are weight coefficients optimized through prototype experiments (such as 0.7, 0.3, 0.05). is the normalized change rate within the decision time window , defined as: ; Where, is the built-in timing constant of the control mainboard (such as 30s). If the pressure still fluctuates significantly within this time window , then is positive, the suppression term increases to prevent misjudgment; if the pressure tends to be stable, then is close to zero, and the index value is mainly determined by the pressure difference amplitude and the oil return state.

[0032] The control logic stipulates that when and the decision duration is greater than , it is considered that the system has stabilized in the three physical fields of heat, pressure, and oil, and the mainboard immediately issues a start signal , while turning off heating zone one and heating zone two, ending the preheating phase. This command directly drives the compressor contactor through the digital output interface of the mainboard, making the compressor enter the actual running state. The entire process does not perform dynamic feedback optimization, relying entirely on one-time decision execution to ensure system behavior reproducibility.

[0033] S4: If the start condition is met, the start mode of the compressor is selected according to the size of the coordination readiness index, and the start operation is performed; after the start is completed, the system is switched to the normal operation mode, the preheating device is removed, and the standard control program is restored.

[0034] Specifically, the only task of this step is to convert the start instruction output in step three into the actual action of the compressor, and at the same time, switch the system state from "preheating-oil preparation" to "normal operation".

[0035] In , the control mainboard first cuts off the power supply of heating band one and heating band two, to avoid the preheating device from continuing to work and causing an energy overshoot. Then, the mainboard sends a power-on signal to the compressor contactor through the relay control circuit, so that the compressor motor is powered on and started. To ensure that the process is physically reproducible and avoid mechanical impact caused by sudden load, this step designs a start execution factor , which is not a new judgment, but a control quantity that maps the judgment result to the actual execution mode.

[0036] ; Among them, is the start execution factor, dimensionless; is the coordination readiness index output in step three; is the coordination threshold value (usually 1.0). If is much higher than the threshold value, then is close to 1, indicating that the compressor can be directly operated according to the standard start mode; if is just close to the threshold value, then will be less than 1, and the control mainboard will automatically select the delay start mode (for example, delay 5 seconds to start), which ensures that the execution action closely follows the judgment of the previous step.

[0037] During execution, the mainboard selects different start curves according to : when , the compressor is directly powered on at full voltage; when , the mainboard controls the soft start module to gradually increase the motor voltage within 2-5 seconds, ensuring that even if the system conditions just meet the requirements, there will be no oil film disturbance or low pressure fluctuation due to instantaneous impact. Take an example: if the output of step three is , then , the system immediately performs standard start; if , just exceeds the 1.0 threshold value, then , the mainboard selects the delay start mode of 5 seconds and starts with gradual pressure increase. Through this mapping, the start behavior is no longer a single action, but closely depends on the previous judgment result, ensuring the closed-loop nature of the control logic.

[0038] After the completion of the compressor start, the control mainboard switches the system operation mode to "normal operation", and at the same time, the standard program of unlocking the condenser fan, the circulating water pump and the EEV opening degree control is executed, so that the heat pump enters a stable heat cycle. At this time, the whole system formally ends the preheating and oil return stage, and enters the continuous heating work.

[0039] In one or more embodiments, as shown in Figure 2 a multi-stage preheating based ultra-high temperature heat pump start-up cooperative control system is disclosed, which comprises: a partition preheating module for collecting original temperature signals and comparing them with preset start-up threshold values; if any temperature does not meet the standard, the corresponding heating device is controlled to be independently heated until the three temperatures all reach the preset threshold values; based on the temperature at the bottom of the gas-liquid separator and the temperature rise rate, it is judged whether the lubricating oil is activated from a high viscosity state to a flow state; an oil return state module for calculating the one-time pre-position opening degree of the electronic expansion valve when the lubricating oil is activated to a flow state, and controlling it to be opened to establish a micro pressure difference, and estimating the size of the micro pressure difference, and judging whether the oil return is completed based on the micro pressure difference; a cooperative decision module for constructing a cooperative readiness index based on the micro pressure difference and the oil return state, and judging whether the system meets the start-up condition; an execution module for selecting the start-up mode of the compressor according to the size of the cooperative readiness index if the start-up condition is met, and performing the start-up operation; after the completion of the start-up, the system is switched to the normal operation mode, the preheating device is unlocked and the standard control program is restored.

[0040] It is worth noting that the specific working process of the multi-stage preheating based ultra-high temperature heat pump start-up cooperative control system provided by the embodiment of the present application is the same as the process of the multi-stage preheating based ultra-high temperature heat pump start-up cooperative control method described in the above embodiment, and will not be repeated here.

[0041] The embodiment of the present application also provides a multi-stage preheating based ultra-high temperature heat pump start-up cooperative control device, which comprises a processor, a memory and a computer program stored in the memory and configured to be executed by the processor, and the processor implements the steps in the above multi-stage preheating based ultra-high temperature heat pump start-up cooperative control method embodiment when executing the computer program, such as the steps S1-S4 described in Figure 1 ; or, the processor implements the functions of each module in the above each system embodiment when executing the computer program.

[0042] Exemplarily, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to implement the present invention. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program in the ultra-high temperature heat pump startup coordinated control device based on multi-stage preheating.

[0043] The multi-stage preheating ultra-high temperature heat pump startup coordinated control device can be a computing device such as a desktop computer, laptop, PDA, or cloud server. The multi-stage preheating ultra-high temperature heat pump startup coordinated control device can include, but is not limited to, a processor and memory. Those skilled in the art will appreciate that the multi-stage preheating ultra-high temperature heat pump startup coordinated control device can also include input / output devices, network access devices, buses, and the like.

[0044] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASAC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor. The processor serves as the control center of the ultra-high temperature heat pump startup coordinated control device based on multi-stage preheating, and utilizes various interfaces and lines to connect various parts of the ultra-high temperature heat pump startup coordinated control device based on multi-stage preheating.

[0045] The memory can be used to store the computer program and / or modules, and the processor realizes various functions of the multi-stage preheating based ultra-high temperature heat pump startup collaborative control device by running or executing the computer program and / or modules stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required by a function, etc.; and the data storage area can store data created according to the running of the air conditioner controller, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (SmartMedaaCard, SMC), a secure digital (SecureDagatal, SD) card, a flash card (FlashCard), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0046] The modules integrated in the multi-stage preheating based ultra-high temperature heat pump startup collaborative control device can be stored in a computer readable storage medium if they are realized in the form of software function units and sold or used as independent products. Based on such understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer readable storage medium. The computer program can implement the steps of the above-mentioned various method embodiments when executed by a processor. The computer program includes computer program code, which can be in the form of source code, object code, executable files or some intermediate forms, etc. The computer readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium, etc.

[0047] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware, and the program can be stored in a computer readable storage medium, and the program can include the processes of the above-mentioned various method embodiments when executed. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0048] The above is the preferred embodiment of the present application, it should be pointed out that, for those skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements are also considered to be within the scope of the present application.

Claims

1. A coordinated control method for starting an ultra-high temperature heat pump based on multi-stage preheating, characterized in that: The method comprises: The original temperature signal is collected and compared with the preset start-up threshold. If any temperature does not meet the standard, the corresponding heating device is controlled to independently heat until all temperatures reach the preset threshold. Based on the temperature and temperature rise rate at the bottom of the gas-liquid separator, it is determined whether the lubricating oil has been activated from a highly viscous state to a fluid state. When the lubricating oil is activated in a flowing state, the pre-position opening of the electronic expansion valve is calculated, and its opening is controlled to establish a micro-pressure difference, and the size of the micro-pressure difference is estimated, and whether the oil return is completed is determined based on the micro-pressure difference; constructing a collaborative readiness index based on the micro-pressure difference and the oil return state, and judging whether a startup condition is met based on the collaborative readiness index; If the startup conditions are met, the startup mode of the compressor is selected according to the size of the collaborative readiness index, and the startup operation is performed; after the startup is completed, the system is switched to normal operating mode, the preheating device is released and the standard control procedure is restored.

2. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1 is characterized in that: The original temperature signal includes the temperature signals of the bottom of the compressor, the bottom of the gas-liquid separator and the water inlet of the evaporator. The temperature signal at the bottom of the compressor is used to represent the actual metal shell temperature at the bottom of the compressor cavity; the temperature signal at the bottom of the gas-liquid separator is used to sense the thermal changes in the metal area just below the oil return hole, and the temperature signal at the water inlet of the evaporator is used to measure the initial temperature of the hot water circulation system sent to the evaporator.

3. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1 is characterized in that: The step of determining whether the lubricating oil has been activated from a high-viscosity state to a fluid state includes: calculating the temperature rise rate of the bottom temperature of the gas-liquid separator per unit time; if the temperature reaches a threshold and the temperature rise rate is lower than a set threshold, determining that the lubricating oil has been activated to a fluid state.

4. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1 is characterized in that: A thermal imbalance suppression term is introduced into the calculation of the pre-position opening of the electronic expansion valve to suppress sudden changes in flow caused by the temperature difference between the compressor and the gas-liquid separator.

5. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1, characterized in that: The establishment of the micro-pressure difference depends on the geometric height difference between the liquid storage container and the gas-liquid separator and the pipeline resistance, and is estimated by the calibration coefficient.

6. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1, characterized in that: The construction of the collaborative readiness index includes: weighted integration of the micro-pressure difference amplitude, oil return status and pressure difference change rate; if the index continuously exceeds a threshold and remains for a certain period of time, it is determined that the startup condition is met.

7. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1, characterized in that: The startup mode includes standard startup and delayed soft startup, and the startup mode is selected according to the ratio of the collaborative readiness index to the threshold.

8. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 7, characterized in that: If the ratio is lower than 1, a delayed soft start method is used to gradually increase the compressor voltage; if the ratio is equal to or higher than 1, a direct standard start method is used.

9. The ultra-high temperature heat pump startup coordinated control method based on multi-stage preheating according to claim 1, characterized in that: Before the compressor starts, no additional pressure or flow sensors are required, and closed-loop control of the entire process is achieved only through temperature signals and valve control.

10. Ultra-high temperature heat pump startup coordinated control system based on multi-stage preheating, characterized in that: The system comprises: The zoned preheating module collects raw temperature signals and compares them with preset start-up thresholds. If any temperature falls below the threshold, the corresponding heating device is controlled to independently heat the system until all three temperatures reach the preset threshold. Based on the temperature and temperature rise rate at the bottom of the gas-liquid separator, it determines whether the lubricating oil has been activated from a highly viscous state to a fluid state. The oil return status module is used to calculate the one-time pre-position opening of the electronic expansion valve when the lubricating oil is activated in the flow state, control its opening to establish a micro-pressure difference, estimate the size of the micro-pressure difference, and determine whether the oil return is completed based on the micro-pressure difference; A collaborative decision module, configured to construct a collaborative readiness index based on the micro-pressure difference and the oil return status, and determine whether the system meets the startup conditions; The execution module is used to select the compressor startup mode according to the size of the collaborative readiness index and perform the startup operation if the startup conditions are met; after the startup is completed, it switches to the normal operating mode of the system, releases the preheating device and restores the standard control program.

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