A control method of a heat pump system and a heat pump system

Abstract

The present application relates to heat pump unit control technical field, disclose a kind of control method and heat pump system of heat pump system, the total water inlet and total water outlet of heat pump system are provided with multiple groups of parallel heat pump subsystems, method includes: obtaining the total water temperature and total water temperature of heat pump system;Based on total water temperature and total water temperature, the total operation demand of heat pump system is obtained by calculation;Based on total operation demand, control target quantity of heat pump subsystems is put into operation;Dynamic adjustment water flow in each running heat pump subsystem, so that the temperature difference of each heat pump subsystem reaches its corresponding target temperature difference.The present application can effectively improve the operation efficiency of heat pump system, significantly improve the control accuracy, reliability and heating stability of system.

Description

Technical Field

[0001] This invention relates to the field of heat pump unit control technology, specifically to a control method for a heat pump system and a heat pump system. Background Technology

[0002] Common dual-system heat pump units typically connect only one large circulating water pump to meet the heat exchange needs of both systems. This has the following disadvantages: 1. Low operating energy efficiency: When heating and hot water demand is low, the heat pump unit will be in a low load state. At this time, only one system is turned on, and the circulating water pump must be turned on (small load, large water pump), resulting in a low overall energy efficiency ratio of the system and wasting electricity.

[0003] 2. Low controllability: It is impossible to precisely control the operating speed of the water pump according to the operating conditions of each system to maximize the heat exchange efficiency of each system.

[0004] 3. Reliability is generally poor: The main circulating water pump serves two systems, making it impossible to accurately assess the operating status of each system and implement corresponding protective measures. When the only circulating water pump fails, the entire heating system will be completely paralyzed, impacting the customer experience. Summary of the Invention

[0005] In view of this, the present invention provides a control method for a heat pump system and a heat pump system to solve the problem of low energy efficiency in the operation of heat pump systems in the prior art.

[0006] In a first aspect, the present invention provides a control method for a heat pump system, wherein multiple sets of parallel heat pump subsystems are arranged between the total inlet and the total outlet of the heat pump system. The method includes: acquiring the total inlet water temperature and the total outlet water temperature of the heat pump system; calculating the total operating demand of the heat pump system based on the total inlet water temperature and the total outlet water temperature; controlling a target number of heat pump subsystems to be put into operation based on the total operating demand; and dynamically adjusting the water flow rate in each operating heat pump subsystem so that the inlet and outlet water temperature difference of each heat pump subsystem reaches its corresponding target temperature difference.

[0007] The heat pump system control method provided by this invention calculates the total operating demand based on the total inlet and outlet water temperatures and controls the number of subsystems put into operation accordingly. This achieves precise matching between load and system capacity, fundamentally solving the energy waste problem of "small load, large pump" under low load conditions and significantly improving the overall energy efficiency ratio of the system. By independently adjusting the water flow rate and controlling the inlet and outlet water temperature difference of each operating subsystem to reach the target value, it achieves refined control of the heat exchange efficiency of each subsystem, ensuring that each subsystem always operates at the optimal heat exchange efficiency point, greatly improving the overall heat exchange performance and control accuracy of the system. By establishing an independent monitoring and control loop for each subsystem, it achieves accurate fault identification and isolation, ensuring that the abnormality of a single subsystem does not affect the normal operation of other subsystems based on the total demand, greatly enhancing the system's operational reliability and heating continuity.

[0008] In one optional implementation, the process of calculating the total operating requirements of the heat pump system based on the total inlet water temperature and the total outlet water temperature includes: calculating the average water temperature based on the total inlet water temperature and the total outlet water temperature; and calculating the total operating requirements by proportional-integral calculation based on the difference between the average water temperature and the preset target water temperature.

[0009] In one optional implementation, the process of controlling the number of heat pump subsystems to be put into operation based on the total operating demand includes: setting multiple sequentially increasing operating demand thresholds, with each pair of adjacent operating demand thresholds forming a threshold interval, and each threshold interval corresponding to a unique desired number of heat pump subsystems to be put into operation; comparing the total operating demand with each threshold interval; and using the number of subsystems to be put into operation corresponding to the threshold interval where the total operating demand is located as the target number.

[0010] In one optional implementation, the process of dynamically adjusting the water flow rate in each operating heat pump subsystem so that the inlet and outlet water temperature difference of each heat pump subsystem reaches its corresponding target temperature difference includes: acquiring the independent inlet water temperature and independent outlet water temperature of each heat pump subsystem respectively, and calculating the independent inlet and outlet water temperature difference of each heat pump subsystem respectively; calculating the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference respectively; identifying the preset temperature difference range in which the temperature difference of each heat pump subsystem is located, and adjusting the water flow rate through the heat pump subsystem in steps according to the fixed adjustment amount corresponding to the preset temperature difference range.

[0011] In one optional implementation, after calculating the temperature difference between the independent inlet and outlet water temperature difference and the target temperature difference for each heat pump subsystem, the method further includes: based on the temperature difference between the independent inlet and outlet water temperature difference and the target temperature difference for each heat pump subsystem, calculating the control quantity for adjusting the water flow rate of each corresponding heat pump subsystem using a proportional-integral-derivative control algorithm; and adjusting the water flow rate through the corresponding heat pump subsystem based on the control quantity.

[0012] In one optional implementation, the method further includes: acquiring independent operating parameters for each operating heat pump subsystem; and performing fault protection for any heat pump subsystem when the independent operating parameters of any heat pump subsystem are abnormal.

[0013] In one optional implementation, the independent operating parameters include: independent outlet water temperature and independent inlet / outlet water temperature difference. The process of fault protection for the heat pump subsystem includes: comparing the independent outlet water temperature and independent inlet / outlet water temperature difference of each heat pump subsystem with preset protection parameters, which include an outlet water temperature frequency limit value, an outlet water temperature frequency reduction value, an outlet water temperature shutdown value, and an inlet / outlet water temperature difference shutdown value; when it is determined that the independent outlet water temperature is greater than the outlet water temperature frequency limit value and less than or equal to the outlet water temperature frequency reduction value, locking the operating frequency of the heat pump subsystem and increasing the water flow rate of the heat pump subsystem; when it is determined that the independent outlet water temperature is greater than the outlet water temperature frequency reduction value and less than or equal to the outlet water temperature shutdown value, reducing the operating frequency of the heat pump subsystem and adjusting the water flow rate of the heat pump subsystem to the maximum; when it is determined that the independent outlet water temperature is greater than the outlet water temperature shutdown value, or when it is determined that the independent inlet / outlet water temperature difference is greater than the inlet / outlet water temperature difference shutdown value, controlling the heat pump subsystem to shut down.

[0014] The control method for a heat pump system provided by this invention establishes a multi-parameter, multi-level linkage protection mechanism based on independent outlet water temperature and inlet / outlet water temperature difference, achieving accurate identification and protection against heat pump subsystem faults. When an abnormal outlet water temperature is detected, the system sequentially executes frequency limiting and flow rate increase, frequency reduction and flow rate maximization, until finally shutting down, forming a progressively stronger protection gradient. This effectively avoids false shutdowns caused by instantaneous fluctuations in single-point parameters, while providing the system with opportunities for self-adjustment and recovery. Independent monitoring of the inlet / outlet water temperature difference can promptly detect hidden faults such as abnormal water flow or a sudden drop in heat exchange efficiency. A judgment logic parallel to temperature protection ensures that corresponding protection actions are activated when any abnormal condition is triggered. This layered, parallel protection strategy maximizes system safety while significantly reducing the probability of unnecessary shutdowns, improving the continuity and intelligence of system operation.

[0015] In a second aspect, the present invention provides a heat pump system, comprising: a controller, a main inlet water pipe, a main outlet water pipe, a main inlet water temperature sensor, a main outlet water temperature sensor, and at least one heat pump subsystem, wherein the controller is electrically connected to the main inlet water temperature sensor, the main outlet water temperature sensor, and each heat pump subsystem, and the controller is used to execute the method described in the first aspect or any corresponding embodiment thereof; each heat pump subsystem is connected in parallel between the main inlet water pipe and the main outlet water pipe, and each heat pump subsystem includes: an inlet water temperature sensor, a circulating water pump, a heating unit, and an outlet water temperature sensor arranged sequentially along the water flow direction; the main inlet water temperature sensor is disposed on the main inlet water pipe; the main outlet water temperature sensor is disposed on the main outlet water pipe.

[0016] The heat pump system provided by this invention achieves high modularity and scalability in its hardware architecture by using multiple parallel and structurally identical heat pump subsystems in conjunction with a controller to execute the aforementioned control method. Each subsystem integrates complete independent temperature sensing, flow drive, and heating functions, enabling the controller to independently monitor and precisely regulate the operating status of each subsystem. This ensures that while improving overall operating energy efficiency and heat exchange accuracy, a fault in any subsystem can be effectively isolated without affecting the normal operation of the rest, thus achieving a highly efficient, reliable, and flexible integrated heat pump solution at the system level.

[0017] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method described in the first aspect or any corresponding embodiment thereof.

[0018] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the method described in the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic flowchart of a first method for controlling a heat pump system according to an embodiment of the present invention; Figure 2 This is a second flowchart illustrating the control method of a heat pump system according to an embodiment of the present invention; Figure 3 This is a third flowchart illustrating the control method of a heat pump system according to an embodiment of the present invention; Figure 4 This is a fourth flowchart illustrating the control method of a heat pump system according to an embodiment of the present invention; Figure 5 This is a fifth flowchart illustrating the control method of a heat pump system according to an embodiment of the present invention; Figure 6 This is a sixth flowchart illustrating the control method of a heat pump system according to an embodiment of the present invention; Figure 7 This is a composition diagram of a heat pump system according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0023] This embodiment provides a control method for a heat pump system, wherein multiple sets of parallel heat pump subsystems are set between the main inlet and main outlet of the heat pump system, such as... Figure 1 As shown, the method includes: Step S1: Obtain the total inlet water temperature and total outlet water temperature of the heat pump system.

[0024] Specifically, by deploying high-precision temperature sensors at key nodes in the main circulation pipeline of the heat pump system—namely, the main inlet and main outlet—the system can monitor the main inlet and main outlet temperatures in real time. The main inlet temperature directly reflects the heat load status of the low-temperature return water from the user's terminal, while the main outlet temperature characterizes the actual hot water temperature level currently output by the system. Simultaneous monitoring of these two temperature parameters not only provides instantaneous temperature difference data to assess the current heat exchange intensity, but also allows the system to accurately determine whether the current heating / hot water supply meets the set targets.

[0025] Step S2: Calculate the total operating requirements of the heat pump system based on the total inlet water temperature and the total outlet water temperature.

[0026] Specifically, after obtaining the total inlet and outlet water temperature data, the system calculates the deviation between the actual average water temperature and the preset target water temperature through an embedded algorithm. This deviation is input into a preset, adjustable control algorithm model (e.g., a demand calculator using a proportional-integral algorithm), which quantizes the continuous temperature difference signal into a discrete total operating demand value that characterizes the instantaneous total heat power required by the system. This enables the system to accurately assess the total heat power required to eliminate the current water temperature deviation.

[0027] Step S3: Based on the total operating requirements, control the target number of heat pump subsystems to be put into operation.

[0028] Specifically, the system compares the calculated total operating demand with a pre-set series of operating demand thresholds arranged in ascending order. These thresholds are set based on the rated capacity and energy efficiency curves of different numbers of heat pump subsystems. By determining which demand interval defined by adjacent thresholds the total operating demand falls into, each interval uniquely corresponds to an optimal number of subsystems to operate. This allows the system to accurately activate the minimum necessary number of heat pump subsystems to meet current demand, achieving on-demand energy supply. This avoids simultaneous inefficient operation of all subsystems under low load conditions and ensures sufficient capacity output under high load conditions, significantly optimizing system energy efficiency under partial load.

[0029] Step S4: Dynamically adjust the water flow rate in each operating heat pump subsystem so that the inlet and outlet water temperature difference of each heat pump subsystem reaches its corresponding target temperature difference.

[0030] Specifically, after identifying which subsystems are operational, an independent, closed-loop flow regulation loop is activated for each operating subsystem. The independent inlet and outlet water temperature difference of that subsystem is used as the core controlled variable, and compared with the target temperature difference to obtain the temperature difference deviation. Based on this temperature difference deviation, a control signal is output through a specific regulation algorithm (such as PID control or tiered logic) to dynamically adjust the water flow rate on that branch, so that the actual temperature difference of the subsystem approaches and stabilizes near the target temperature difference. In this way, the water flow rate of each subsystem is independently optimized, ensuring that it operates under optimal heat exchange conditions at various load rates, avoiding pump power waste due to excessive flow or insufficient heat exchange due to insufficient flow, ultimately achieving a secondary improvement in the overall system energy efficiency and stable control of the supply water temperature.

[0031] The heat pump system control method provided in this embodiment calculates the total operating demand based on the total inlet and outlet water temperatures and controls the number of subsystems put into operation accordingly. This achieves precise matching between load and system capacity, fundamentally solving the energy waste problem of "small load, large pump" under low load conditions and significantly improving the overall energy efficiency ratio of the system. By independently adjusting the water flow rate and controlling the inlet and outlet water temperature difference of each operating subsystem to reach the target value, it achieves fine-grained control of the heat exchange efficiency of each subsystem, ensuring that each subsystem always operates at the optimal heat exchange efficiency point, greatly improving the overall heat exchange performance and control accuracy of the system. By establishing an independent monitoring and control loop for each subsystem, it achieves accurate fault identification and isolation, ensuring that the abnormality of a single subsystem does not affect the normal operation of other subsystems based on the total demand, greatly enhancing the system's operational reliability and heating continuity.

[0032] In some alternative implementations, the process of calculating the total operating requirements of the heat pump system based on the total inlet water temperature and the total outlet water temperature, such as... Figure 2 As shown, it includes: Step S21: Calculate the average water temperature based on the total inlet water temperature and the total outlet water temperature.

[0033] Step S22: Based on the difference between the average water temperature and the preset target water temperature, the total operating requirements are obtained through proportional-integral calculation.

[0034] Specifically, by arithmetically averaging the real-time collected total inlet and outlet water temperatures, an average water temperature value reflecting the overall thermal state of the system is obtained. This value effectively integrates the temperature characteristics of both the supply and return ends of the system, overcoming potential local deviations in single-point temperature monitoring. Subsequently, this average water temperature is compared with a preset target water temperature to obtain the current real-time water temperature deviation of the system. This deviation is input into a preset proportional-integral controller for processing: the proportional unit generates a fast response component based on the instantaneous amplitude of the current deviation, enabling timely tracking of load fluctuations; the integral unit performs cumulative calculations of the deviation over time to eliminate steady-state control errors in the system. Through weighted synthesis of the proportional and integral term outputs, a continuous and quantified total operating demand parameter is finally generated.

[0035] Specifically, the system controller calculates the total operating demand D based on the total inlet water temperature, the total outlet water temperature, and the target temperature. D = Kp × ΔT + I, where Kp is the proportionality coefficient, ΔT is the difference between the actual average water temperature and the target temperature, and I is the integral term. The controller updates the total operating demand D every predetermined time interval Tt (e.g., 1 minute).

[0036] In some alternative implementations, the process of controlling the target number of heat pump subsystems to be put into operation based on total operating demand, such as... Figure 3 As shown, it includes: Step S31: A plurality of operation demand thresholds increasing sequentially are set, every two adjacent operation demand thresholds form a threshold interval, and each threshold interval corresponds to a unique expected put-in number of heat pump subsystems.

[0037] Specifically, the controller preconfigures a set of numerically increasing operation demand thresholds according to the design capacity, energy efficiency characteristics and operation constraints of each heat pump subsystem. These operation demand thresholds divide the entire possible total operation demand range into a plurality of continuous interval segments, and assign a unique corresponding expected put-in number of heat pump subsystems to each such interval segment. This number represents the theoretically optimal number of units to be started by the system to achieve efficient and stable operation at this demand level.

[0038] Step S32: The total operation demand is compared with each threshold interval.

[0039] Specifically, the controller compares the current total operation demand value calculated or acquired in real time with all the threshold intervals defined in step S31 one by one, and checks whether the value of the total operation demand is greater than the lower limit threshold of a certain interval and less than or equal to the upper limit threshold thereof.

[0040] Step S33: The put-in number corresponding to the threshold interval where the total operation demand is located is taken as the target number.

[0041] Specifically, after the specific threshold interval where the current total operation demand is located is determined in step S32, the controller directly obtains the expected put-in number of heat pump subsystems corresponding to the interval according to the mapping relationship established in step S31, and sets this number as the target number to be executed currently. Subsequently, the target number is converted into a specific device-level control instruction, for example, controlling the start and stop of the heat pump subsystem with a specific number.

[0042] For example, a startup threshold A, a single-system operation threshold B and a dual-subsystem operation threshold C are set, where A is less than B, and B is less than C. The total operation demand D is compared with the startup threshold A, the single-system operation threshold B and the dual-subsystem operation threshold C respectively: (1) If D>A and D<C, only one heat pump subsystem is turned on.

[0043] (2) If D≥C, two heat pump subsystems are turned on at the same time.

[0044] (3) During single-system operation, if D≥B, the second heat pump subsystem is started.

[0045] (4) During dual-system operation, if D<B, one heat pump subsystem is turned off.

[0046] In some alternative implementations, the process of dynamically adjusting the water flow rate in each operating heat pump subsystem to achieve the corresponding target temperature difference between the inlet and outlet water of each heat pump subsystem is as follows: Figure 4 As shown, it includes: Step S41: Obtain the independent inlet water temperature and independent outlet water temperature of each heat pump subsystem, and calculate the independent inlet and outlet water temperature difference of each heat pump subsystem.

[0047] Specifically, the controller synchronously reads the real-time temperature data of each branch through independently configured inlet and outlet water temperature sensors for each heat pump subsystem. Subsequently, for each operating subsystem, the difference between its independent outlet water temperature and independent inlet water temperature is calculated, thereby obtaining the independent inlet and outlet water temperature difference, which characterizes the current instantaneous heat exchange intensity of the subsystem. The independent inlet and outlet water temperature difference directly reflects the actual temperature rise of water flowing through the heat exchange unit of the subsystem and is the core raw parameter for evaluating its heat exchange efficiency and load status.

[0048] Step S42: Calculate the temperature difference between the independent inlet and outlet water temperature difference and the target temperature difference for each heat pump subsystem.

[0049] Specifically, after acquiring the independent inlet and outlet water temperature difference for each subsystem, the controller compares it with a pre-set target temperature difference for that subsystem. The target temperature difference is a preset value, typically corresponding to the optimal heat transfer efficiency point of this type of heat exchanger under ideal operating conditions. The controller calculates the algebraic difference between the independent inlet and outlet water temperature differences and the target temperature difference, thus obtaining the real-time temperature difference deviation value. The sign and magnitude of this deviation value indicate whether the current heat exchange state is higher or lower than the expected efficiency, and the degree of deviation, thereby transforming the actual operating state of the heat exchanger into a clear error signal that can be processed by the control algorithm.

[0050] Step S43: After identifying the preset temperature difference range where the temperature difference of each heat pump subsystem is located, adjust the water flow rate through the heat pump subsystem step by step according to the fixed adjustment amount corresponding to the preset temperature difference range.

[0051] Specifically, the controller matches the temperature difference deviation value of each subsystem calculated in step S42 with a set of predefined temperature difference intervals divided according to the magnitude of the deviation, identifying the specific interval range into which the deviation value falls. Each temperature difference interval is associated with a fixed water flow adjustment, such as increasing or decreasing a specific speed setting or duty cycle step. Based on the matching result, the controller issues a command to the subsystem to gradually change its output according to the determined fixed adjustment amount, thereby regulating the water flow through the subsystem. This interval-based regulation strategy, through discretized control actions, drives the actual inlet and outlet water temperature difference of each subsystem to approach its target value in a simple and reliable manner, ultimately achieving independent optimization and stable control of the heat exchange efficiency of each subsystem.

[0052] For example, during system operation, the controller monitors the individual inlet and outlet water temperatures of each subsystem in real time, calculates the corresponding independent inlet and outlet water temperature difference Tdif, and makes a judgment every 60 seconds. It then adjusts the pump speed of that subsystem to make the independent inlet and outlet water temperature difference Tdif approach the preset target temperature difference Ttra. For example, the pump speed duty cycle step ΔSTEP is adjusted according to the following rule: ΔT = Tdif - Ttra, where N is the pump speed adjustment range parameter per cycle. (1) When 3℃≤ΔT, control ΔSTEP=2N to significantly increase the rotational speed.

[0053] (2) When 1℃≤ΔT<3℃, control ΔSTEP=N to increase the rotation speed.

[0054] (3) When -1℃ < ΔT < 1℃, control ΔSTEP = 0 and maintain the rotation speed.

[0055] (4) When -3℃ < ΔT ≤ -1℃, control ΔSTEP = -N to reduce the speed.

[0056] (5) When ΔT≤-3℃, control ΔSTEP=-2N to significantly reduce the speed.

[0057] In some alternative implementations, after calculating the temperature difference between the independent inlet and outlet water temperature differences of each heat pump subsystem and the target temperature difference, as follows: Figure 5 As shown, it also includes: Step S44: Based on the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference, the control quantity for adjusting the water flow of each corresponding heat pump subsystem is calculated using a proportional-integral-derivative control algorithm.

[0058] Specifically, the controller uses the independent temperature difference deviation value of each subsystem obtained in step S42 as an input signal, feeding it into a dedicated proportional-integral-derivative (PID) control algorithm module. This algorithm performs real-time calculations on the input signal: the proportional term provides a rapid response based on the instantaneous magnitude of the current deviation, the integral term eliminates steady-state error by accumulating historical deviations, and the derivative term makes proactive adjustments based on the trend of deviation changes to suppress system oscillations. Through weighted synthesis of the three outputs, the algorithm generates a continuous, dynamic control output for each heat pump subsystem. This control output is a precise adjustment command, representing the magnitude and direction of the water flow adjustment required to eliminate the current temperature difference deviation and stabilize the system.

[0059] Step S45: Adjust the water flow rate through the corresponding heat pump subsystem based on the control quantity.

[0060] Specifically, after obtaining the precise control quantity for each subsystem calculated in step S44, the controller converts this digital quantity into an analog signal or pulse width modulation signal that can be recognized by the corresponding actuator (such as a variable frequency drive-driven circulating water pump or an electric regulating valve). Subsequently, this command signal is sent to the flow regulating actuator of the corresponding heat pump subsystem, driving its operating state to change continuously or in steps, thereby precisely adjusting the water flow rate through the heat exchanger of that subsystem. Through closed-loop feedback, the change in water flow rate will, in turn, affect the independent inlet and outlet water temperature difference of the subsystem, causing it to gradually approach and stabilize near the target value.

[0061] For example, after obtaining the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference, speed regulation based on a PID algorithm can also be used, and the calculation formula is as follows: Δu(k)=Kp×[e(k)-e(k-1)]+(Ki×T)×e(k)+(Kd / T)×[e(k)-2e(k-1)+e(k-2)] Where Δu(k) is the increment of the duty cycle step of the calculated pump speed; k is the current sampling period; e(k) is the current temperature difference deviation, e(k)=Ttra-Tdif(k); e(k-1) is the historical deviation of the previous period; e(k-2) is the historical deviation of the previous two periods; Kp is the proportional coefficient of the controller; Ki is the integral coefficient of the controller; Kd is the derivative coefficient of the controller; T is the sampling period in seconds.

[0062] In some alternative implementations, such as Figure 6 As shown, the method also includes: Step S5: Obtain the independent operating parameters of each running heat pump subsystem.

[0063] Specifically, during the operation of the heat pump subsystem, the controller continuously acquires multi-dimensional parameters characterizing its key operating status through a sensor network independently configured for each subsystem. These parameters typically include, but are not limited to: independent outlet water temperature, used to monitor the heat load status and potential overheating risks at the heat exchange terminal; independent inlet water temperature, used to assess the return water condition; and independent inlet and outlet water temperature difference, used to determine the heat exchange efficiency and water flow matching degree in real time.

[0064] Step S6: When any independent operating parameter of a heat pump subsystem is abnormal, fault protection is performed on that heat pump subsystem.

[0065] Specifically, when the controller continuously monitors and identifies, in step S5, any independent operating parameter of the heat pump subsystem (such as outlet water temperature or inlet / outlet water temperature difference) exceeding a preset safety threshold, it determines that the subsystem has malfunctioned. Subsequently, the system immediately activates a tiered protection protocol for that specific subsystem. This protocol, based on the type of abnormal parameter, the severity of the exceedance, and the duration, executes progressive protection actions ranging from mild intervention to forced shutdown, such as limiting compressor frequency increase, forcibly reducing frequency, increasing water pump speed, and ultimately shutting down the compressor and water pump. The entire protection process applies only to the single subsystem malfunctioning, ensuring that the control processes of other normally operating subsystems (such as start-up / shutdown and frequency regulation based on total demand) remain completely unaffected.

[0066] Specifically, independent operating parameters include: independent outlet water temperature and independent inlet / outlet water temperature difference. The process of fault protection for this heat pump subsystem includes: (1) Compare the independent outlet water temperature Tout and the independent inlet and outlet water temperature difference of a heat pump subsystem with the preset protection parameters. The preset protection parameters include the outlet water temperature frequency limiting value TPro1, the outlet water temperature frequency reduction value TPro2, the outlet water temperature shutdown value TPro3, and the inlet and outlet water temperature difference shutdown value TdifPro, where TPro1 > TPro2 > TPro3 > TdifPro.

[0067] (2) When it is determined that the independent outlet water temperature of one of the heat pump subsystems is greater than the outlet water temperature frequency limit value and less than or equal to the outlet water temperature frequency reduction value, i.e., TPro1<Tout≤TPro2, the operating frequency of the heat pump subsystem is locked and the water flow of the heat pump subsystem is increased. For example, the compressor frequency of the subsystem is locked (prohibited from rising), and the pump speed is increased by 1 level. The adjustment is made once every 20 seconds.

[0068] (3) When it is determined that the independent outlet water temperature of one of the heat pump subsystems is greater than the outlet water temperature frequency reduction value and less than or equal to the outlet water temperature shutdown value, i.e., TPro2<Tout≤TPro3, reduce the operating frequency of the heat pump subsystem and adjust the water flow of the heat pump subsystem to the maximum. For example, reduce the compressor frequency of the subsystem by 2Hz and increase the water pump speed to the maximum. Adjust once every 20 seconds.

[0069] (4) When it is determined that the independent outlet water temperature of one of the heat pump subsystems is greater than the outlet water temperature shutdown value, i.e., Tout>TPro3, or when it is determined that the independent inlet and outlet water temperature difference is greater than the inlet and outlet water temperature difference shutdown value, i.e., Tdif>TdifPro, control the heat pump subsystem to shut down, for example, turn off the compressor and water pump of the subsystem.

[0070] Optionally, when the controller performs other protections such as high-pressure protection or low-pressure protection based on the fault of any subsystem, it will also shut down the compressor and water pump of that subsystem separately, take corresponding measures for that subsystem, actively adjust its operating parameters, avoid shutdown faults in advance, and ensure system safety when necessary, without affecting the normal operation of other normal subsystems, reducing water temperature fluctuations and ensuring the continuous heating capacity of the system.

[0071] This embodiment provides a heat pump system, such as Figure 7 As shown, it includes: a controller 1, a main inlet water pipe 2, a main outlet water pipe 3, a main inlet water temperature sensor 4, a main outlet water temperature sensor 5, and at least one heat pump subsystem 6. The controller 1 is electrically connected to the main inlet water temperature sensor 4, the main outlet water temperature sensor 5, and each heat pump subsystem 6. The main inlet water temperature sensor 4 is installed on the main inlet water pipe 2, and the main outlet water temperature sensor 5 is installed on the main outlet water pipe 3.

[0072] Figure 7 In this configuration, each heat pump subsystem 6 is connected in parallel between the main inlet pipe 2 and the main outlet pipe 3. Each heat pump subsystem 6 includes: an inlet water temperature sensor 61, a circulating water pump 62, a heating unit 63, and an outlet water temperature sensor 64, arranged sequentially along the water flow direction. The controller 1 is used to execute the method of the above embodiment or any corresponding implementation thereof.

[0073] Specifically, Figure 7 In this system, controller 1 serves as the central processing unit, and the main inlet water pipe 2 and the main outlet water pipe 3 constitute the system-level water circulation backbone. The main inlet water temperature sensor 4 and the main outlet water temperature sensor 5 are respectively deployed on the above-mentioned pipes to collect the main inlet water temperature and the main outlet water temperature, which characterize the overall thermal state of the system, in real time, and transmit the data to controller 1.

[0074] Specifically, Figure 7 In this system, multiple heat pump subsystems 6 are connected in parallel between the main inlet water pipe 2 and the main outlet water pipe 3, forming a parallel energy supply module. Each heat pump subsystem 6 integrates, sequentially along the water flow direction, the following components: an inlet water temperature sensor 61, a circulating water pump 62, a heating unit 63, and an outlet water temperature sensor 64. The inlet water temperature sensor 61 and the outlet water temperature sensor 64 are used to collect the independent inlet and outlet water temperatures of the subsystem; the circulating water pump 62 is used to independently regulate the water flow rate through the subsystem; and the heating unit 63, as the core heat exchange component, may include a compressor, heat exchanger, throttling device, etc.

[0075] Specifically, Figure 7In this embodiment, controller 1 communicates with all temperature sensors and electrical devices within the heat pump subsystem 6 via electrical connections and executes the control method described above. The controller 1's control logic closed loop is as follows: First, it calculates the total system operating demand based on data from the total inlet water temperature sensor 4 and the total outlet water temperature sensor 5; second, based on this total operating demand, it determines the target number of heat pump subsystems 6 that need to be put into operation and controls the corresponding number of heating units 63 and their circulating water pumps 62 to start; finally, for each operating heat pump subsystem 6, based on data collected by its independent inlet water temperature sensor 61 and outlet water temperature sensor 64, it independently adjusts the speed of its circulating water pump 62 to control the inlet and outlet water temperature difference of that subsystem to approach a preset target value, thereby achieving precise closed-loop control of the heat exchange process of each subsystem. The entire control process is accomplished by controller 1 through the fusion processing of multi-level sensor signals and the independent driving of multiple actuators.

[0076] It should be noted that the other control methods of the controller in this embodiment are the same as those in the above embodiments or any corresponding implementation methods, and will not be repeated here.

[0077] The heat pump system provided in this embodiment achieves high modularity and scalability in its hardware architecture by using multiple parallel and structurally identical heat pump subsystems in conjunction with a controller to execute the aforementioned control method. Each subsystem integrates complete independent temperature sensing, flow drive, and heating functions, enabling the controller to independently monitor and precisely regulate the operating status of each subsystem. This ensures that while improving overall operating energy efficiency and heat exchange accuracy, a fault in any subsystem can be effectively isolated without affecting the normal operation of the rest, thus achieving a highly efficient, reliable, and flexible integrated heat pump solution at the system level.

[0078] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0079] The following is a detailed reference. Figure 8 The diagram illustrates a structural schematic suitable for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 001, which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 002 or a program loaded from memory 008 into random access memory (RAM) 003. The RAM 003 also stores various programs and data required for the operation of the electronic device. The processor 001, ROM 002, and RAM 003 are interconnected via bus 004. An input / output (I / O) interface 005 is also connected to bus 004.

[0080] Typically, the following devices can be connected to I / O interface 005: input devices 006 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 007 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 008 including, for example, magnetic tapes, hard disks, etc.; and communication devices 009. Communication device 009 allows electronic devices to exchange data via wireless or wired communication with other devices. Although Figure 8 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0081] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory 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 communication device 009, or installed from memory 008, or installed from ROM 002. When the computer program is executed by processor 001, it performs the functions defined in the methods of the embodiments of the present invention.

[0082] Figure 8 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments of the present invention.

[0083] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0084] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0085] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A control method for a heat pump system, characterized in that, The method includes setting up multiple parallel heat pump subsystems between the main inlet and the main outlet of the heat pump system. Obtain the total inlet water temperature and total outlet water temperature of the heat pump system; The total operating requirements of the heat pump system are calculated based on the total inlet water temperature and the total outlet water temperature. Based on the total operational requirements, the target number of heat pump subsystems will be put into operation. The water flow rate in each operating heat pump subsystem is dynamically adjusted so that the inlet and outlet water temperature difference of each heat pump subsystem reaches its corresponding target temperature difference. The process of controlling the operation of a target number of heat pump subsystems based on the total operating demand includes: Multiple sequentially increasing operation demand thresholds are set, and each pair of adjacent operation demand thresholds constitutes a threshold interval. Each threshold interval corresponds to a unique number of desired heat pump subsystems to be put into operation. The total operational requirements are compared with each of the threshold intervals; The number of inputs corresponding to the threshold range where the total operating demand is located is taken as the target number.

2. The method according to claim 1, characterized in that, The process of calculating the total operating requirements of the heat pump system based on the total inlet water temperature and the total outlet water temperature includes: The average water temperature is calculated based on the total inlet water temperature and the total outlet water temperature. The total operating requirements are obtained by proportional-integral calculation based on the difference between the average water temperature and the preset target water temperature.

3. The method according to claim 1, characterized in that, The process of dynamically adjusting the water flow rate in each operating heat pump subsystem to ensure that the inlet and outlet water temperature difference of each heat pump subsystem reaches its corresponding target temperature difference includes: The independent inlet and outlet water temperatures of each heat pump subsystem are obtained, and the independent inlet and outlet water temperature difference of each heat pump subsystem is calculated. Calculate the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference; After identifying the preset temperature difference range in which the temperature difference of each heat pump subsystem is located, the water flow rate through the heat pump subsystem is adjusted stepwise according to the fixed adjustment amount corresponding to the preset temperature difference range.

4. The method according to claim 3, characterized in that, After calculating the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference, the process further includes: Based on the temperature difference between the independent inlet and outlet water temperature difference of each heat pump subsystem and the target temperature difference, the control quantity for adjusting the water flow of each corresponding heat pump subsystem is calculated by the proportional-integral-derivative control algorithm. Based on the control quantity, the water flow rate through the corresponding heat pump subsystem is adjusted.

5. The method according to claim 1, characterized in that, Also includes: Obtain the independent operating parameters of each running heat pump subsystem; When any independent operating parameter of a heat pump subsystem is abnormal, fault protection is provided for that heat pump subsystem.

6. The method according to claim 5, characterized in that, The independent operating parameters include: independent outlet water temperature and independent inlet and outlet water temperature difference. The process of fault protection for this heat pump subsystem includes: The independent outlet water temperature and independent inlet / outlet water temperature difference of each heat pump subsystem are compared with preset protection parameters, which include outlet water temperature frequency limit value, outlet water temperature frequency reduction value, outlet water temperature shutdown value, and inlet / outlet water temperature difference shutdown value. When it is determined that the independent outlet water temperature is greater than the outlet water temperature frequency limit value and less than or equal to the outlet water temperature frequency reduction value, the operating frequency of the heat pump subsystem is locked and the water flow rate of the heat pump subsystem is increased. When it is determined that the independent outlet water temperature is greater than the outlet water temperature frequency reduction value and less than or equal to the outlet water temperature shutdown value, the operating frequency of the heat pump subsystem is reduced and the water flow rate of the heat pump subsystem is adjusted to the maximum. When it is determined that the independent outlet water temperature is greater than the outlet water temperature shutdown value, or when it is determined that the independent inlet and outlet water temperature difference is greater than the inlet and outlet water temperature difference shutdown value, the heat pump subsystem is controlled to shut down.

7. A heat pump system, characterized in that, include: The system comprises a controller, a main inlet water pipe, a main outlet water pipe, a main inlet water temperature sensor, a main outlet water temperature sensor, and at least one heat pump subsystem. The controller is electrically connected to the total inlet water temperature sensor, the total outlet water temperature sensor and each of the heat pump subsystems, and the controller is used to perform the method according to any one of claims 1 to 6; Each of the heat pump subsystems is connected in parallel between the main inlet pipe and the main outlet pipe. Each heat pump subsystem includes: an inlet water temperature sensor, a circulating water pump, a heating unit, and an outlet water temperature sensor arranged sequentially along the water flow direction. The main inlet water temperature sensor is installed on the main inlet water pipe; The main outlet water temperature sensor is installed on the main outlet water pipe.

8. A computer device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method according to any one of claims 1 to 6.

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