Temperature control method for heating, ventilation and air conditioning system, and heating, ventilation and air conditioning system controller

Abstract

The present disclosure provides a temperature control method for a heating, ventilation and air conditioning system, comprising the following steps: acquiring the current temperature of a heating, ventilation and air conditioning system; calculating a heating rate and a cooling rate of the heating, ventilation and air conditioning system; respectively calculating a heating duration and a cooling duration required by the heating, ventilation and air conditioning system; entering a control stage while exiting a prediction stage; and after entering the control stage, controlling the continuous heating time and the continuous cooling time of the heating, ventilation and air conditioning system on the basis of the heating duration and the cooling duration, so that the current temperature is kept within an amplitude error interval of a set temperature. Also provided is a heating, ventilation and air conditioning system controller. The heating duration and the cooling duration are calculated on the basis of the heating rate and the cooling rate, respectively, and the continuous heating time and the continuous cooling time of the heating, ventilation and air conditioning system are controlled, allowing the existence of an acceptable temperature difference, enabling the current temperature to be dynamically stable within an amplitude error of an allowed set temperature, reducing the number of temperature regulations and reducing power consumption.

Description

A temperature control method and controller for a heating, ventilation, and air conditioning (HVAC) system

[0001] Cross-references to related applications

[0002] This disclosure claims priority to Chinese Patent Application No. 202411687054.X, filed on November 22, 2024, entitled "A Temperature Control Method and Controller for a Heating, Ventilation and Ventilation System", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of temperature control technology for HVAC systems, and in particular to a temperature control method and controller for HVAC systems. Background Technology

[0004] Heating, ventilation, and air conditioning systems mainly include two types: HVAC and HVACR. HVAC (Heating, Ventilation, Air-conditioning, and Cooling) is a system or related equipment responsible for heating, ventilation, and air conditioning in indoor spaces or vehicles. It consists of three main parts: heat medium preparation (heat source), heat medium transportation, and heat medium utilization (heat dissipation equipment). It can control the temperature and humidity of the air, improving the comfort of indoor spaces or vehicles. Some HVAC systems also include a cooler, i.e., HVACR (Heating, Ventilation, and Air Conditioning, Refrigeration). In addition to heating, ventilation, and air conditioning, it also includes a refrigerant circuit for introducing fluids, removing heat from the treated fluids through a refrigeration cycle (e.g., vapor compression cycle).

[0005] Thermostats in HVAC systems are used to control the temperature of single-stage or multi-stage traditional HVAC systems or heat pump systems. They typically employ specific algorithms to control the air outlets to blow cold or hot air by turning the cooler or heater on or off, thereby maintaining the indoor temperature stably near the set temperature.

[0006] Common algorithms include threshold comparison and PID algorithms. Threshold comparison compares the current temperature with a preset temperature to determine whether to turn the heater / cooler on or off, but it suffers from large control errors. Taking the control of a heater in an HVAC system as an example, when the heater is turned on, causing the indoor temperature to rise, it takes time for the indoor temperature to reach the temperature sensor inside the HVAC system. That is, by the time the temperature sensor detects that the set temperature has been reached, the indoor temperature is already higher than the set temperature, resulting in an error. When the heater is turned off, due to thermal inertia, the indoor temperature will rise for a period before starting to fall, thus introducing another error. Similarly, when controlling the cooling of a cooler, some error will also occur. Furthermore, due to differences in room insulation and the heat transfer characteristics of the HVAC system itself, thermal inertia becomes more pronounced, leading to larger control errors.

[0007] The PID algorithm uses the PWM algorithm to adjust a fixed heating / cooling rate to a variable rate. When the indoor temperature is near the set temperature, high-frequency PWM is needed to stabilize the temperature change rate at a small value to reduce the impact error caused by a large rate. However, the PID algorithm is easily affected by the ambient temperature, making the parameter tuning process very difficult. Moreover, the purpose of the PID algorithm is to eliminate control error, which may require frequent switching control, which will have an adverse effect on the service life of the HVAC system. Summary of the Invention

[0008] To address the shortcomings of the aforementioned technologies, this disclosure presents a temperature control method for a heating, ventilation, and air conditioning (HVAC) system and an HVAC system controller.

[0009] The temperature control method for a heating, ventilation, and air conditioning system disclosed herein includes the following steps:

[0010] Collect the current temperature of the temperature-controlled environment of the HVAC system according to the temperature measurement cycle;

[0011] Entering the prediction phase, the cooling rate and heating rate of the HVAC system are calculated;

[0012] The cooling rate is calculated as follows:

[0013] Calculate the rate of temperature change when the temperature drops from the previous temperature to the current temperature less than or equal to the minimum allowable temperature within a temperature measurement cycle, and use this as the cooling rate.

[0014] The heating rate is calculated as follows:

[0015] The rate of temperature change from the previous moment to the current temperature being greater than or equal to the maximum allowable temperature is calculated within a temperature measurement cycle and is taken as the heating rate.

[0016] Based on the heating rate, the cooling rate, and the amplitude error, calculate the heating time and cooling time required for the HVAC system, respectively.

[0017] Upon exiting the prediction phase, it simultaneously enters the control phase;

[0018] After entering the control phase, the continuous heating time and continuous cooling time of the HVAC system are controlled according to the heating time and cooling time, so as to realize the heating and cooling of the HVAC system respectively, and keep the current temperature within the amplitude error of the set temperature.

[0019] In one embodiment, the heating time is calculated as follows:

[0020] The cooling time is calculated as follows:

[0021] Wherein, is the heating time, is the cooling time, is the heating rate, is the cooling rate, is the amplitude error range width, and is twice the amplitude error.

[0022] In one embodiment, the step of entering the prediction phase, calculating the cooling rate and heating rate of the HVAC system, includes the following steps:

[0023] Determine if the current temperature is greater than or equal to the maximum allowable temperature. If it is, control the HVAC system to cool down.

[0024] After the HVAC system is cooled down, it is determined whether the current temperature is less than or equal to the minimum allowable temperature. If it is less than or equal to the minimum allowable temperature, the HVAC system is heated up, and the cooling rate is calculated.

[0025] After the HVAC system is heated, it is determined whether the current temperature is greater than or equal to the maximum allowable temperature for the second time. If it is greater than or equal to the maximum allowable temperature, the HVAC system is controlled to cool down, and the heating rate is calculated.

[0026] In one embodiment, the step of entering the prediction phase, calculating the cooling rate and heating rate of the HVAC system, includes the following steps:

[0027] Determine if the current temperature is less than or equal to the minimum allowable temperature. If it is, control the HVAC system to heat up.

[0028] After the HVAC system is heated, it is determined whether the current temperature is greater than or equal to the maximum allowable temperature. If it is greater than or equal to the maximum allowable temperature, the HVAC system is controlled to cool down, and the heating rate is calculated.

[0029] After the HVAC system is cooled down, it is determined whether the current temperature is less than or equal to the minimum allowable temperature for the second time. If it is less than or equal to the minimum allowable temperature, the HVAC system is heated up, and the cooling rate is calculated.

[0030] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the first control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0031] The first control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to the set temperature or is lower than the set temperature for the first time.

[0032] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the second control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0033] The second control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to or less than the sum of the set temperature and the amplitude error for the first time.

[0034] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the third control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0035] The third control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to or less than the difference between the set temperature and the amplitude error for the first time.

[0036] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the fourth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0037] The fourth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to the set temperature or exceeds the set temperature for the first time.

[0038] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is found to meet the fifth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0039] The fifth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to or greater than the sum of the set temperature and the amplitude error for the first time.

[0040] In one embodiment, the step of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is found to meet the sixth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously.

[0041] The sixth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to or greater than the difference between the set temperature and the amplitude error for the first time.

[0042] In one embodiment, after entering the control phase;

[0043] The heating and ventilation system is controlled to cool down, and the continuous cooling time is the product of the cooling duration and a first coefficient; then the heating and ventilation system is controlled to alternate between heating and cooling, and the continuous heating time is the product of the heating duration and a second coefficient, and the continuous cooling time is the product of the cooling duration and a third coefficient.

[0044] In one embodiment, after entering the control phase, the HVAC system is controlled to heat up, and the heating duration is the product of the heating duration and a first coefficient; then the HVAC system is controlled to alternate between cooling and heating, and the cooling duration is the product of the cooling duration and a second coefficient, and the heating duration is the product of the heating duration and a third coefficient.

[0045] In one embodiment, the HVAC system includes a heater, which is activated when heating up for a duration equal to the activation duration of the heater; and deactivated when cooling down for a duration equal to the deactivation duration of the heater.

[0046] In one embodiment, the HVAC system includes a heater and a cooler. When heating up, the heater is activated and the cooler is turned off. The heating time is the same as the heater activation time. When cooling down, the heater is turned off for natural cooling, and the cooler is activated for active cooling. The cooling time is the same as the heater shutdown time and the cooler activation time.

[0047] In one embodiment, the method further includes the following steps:

[0048] The prediction phase only begins after the prediction conditions are met.

[0049] The prediction condition is the first prediction condition, which is the first operation of the HVAC system controller.

[0050] In one embodiment, the method further includes the step of: the prediction condition is a second prediction condition, the second prediction condition including one of the following conditions:

[0051] During the control phase, when the peak value of the current temperature is continuously collected and exceeds the maximum allowable temperature for a first set number of times;

[0052] During the control phase, when the valley value of the current temperature is continuously collected and is less than the minimum allowable temperature for a second set number of times;

[0053] During the control phase, the current error is obtained, and the current error is greater than the product of the amplitude error and the threshold coefficient.

[0054] In one embodiment, the maximum allowable temperature is the sum of the set temperature and the equilibrium zone temperature, and the minimum allowable temperature is the difference between the set temperature and the equilibrium zone temperature.

[0055] In one embodiment, the first coefficient is 0.5, and the second and third coefficients are both 1.

[0056] In one embodiment, both the first set number of times and the second set number of times are 3, and the threshold coefficient is 3.

[0057] This disclosure also provides a heating, ventilation, and air conditioning (HVAC) system controller, employing the temperature control method of the HVAC system described above.

[0058] The temperature control method and controller for HVAC systems disclosed herein have the following technical effects: for example, the heating time and cooling time are calculated based on the heating rate and cooling rate, respectively, and the continuous heating time and continuous cooling time of the HVAC system are controlled, allowing an acceptable temperature difference, and making the current temperature dynamically stable within the allowable amplitude error of the set temperature, reducing the number of temperature adjustments and reducing power consumption, while making the temperature control accuracy controllable and the temperature control consistency good. Attached Figure Description

[0059] Figure 1 is a temperature change waveform diagram of an embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure.

[0060] Figure 2 is a temperature change waveform diagram of another embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure;

[0061] Figure 3 is a temperature change waveform diagram of another embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure;

[0062] Figure 4 is a temperature change waveform diagram of another embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure.

[0063] Figure 5 is a temperature change waveform diagram of another embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure.

[0064] Figure 6 is a schematic diagram of the steps in Figure 1;

[0065] Figure 7 is a flowchart of Figure 1;

[0066] Figure 8 is a flowchart of the prediction stage in Figure 7;

[0067] Figure 9 is a flowchart of the control phase in Figure 7;

[0068] Figure 10 is a temperature change waveform diagram of another embodiment of a temperature control method for a heating, ventilation and air conditioning system provided in this disclosure;

[0069] Figure 11 is a flowchart of the prediction phase in Figure 10. Detailed Implementation

[0070] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure are within the scope of protection of this disclosure.

[0071] In one embodiment of this disclosure, as shown in FIG6, a temperature control method for a heating, ventilation, and air conditioning (HVAC) system is disclosed for controlling the temperature of the HVAC system. The HVAC system and its controller constitute a temperature control system. In this embodiment, the application scenario of the temperature control system is a residential building, and the temperature collected or the ambient temperature is the room temperature. The temperature control method includes six steps, S1-S6. These six steps can be consecutive, or there can be other steps known to those skilled in the art between them; even, the order of some of the six steps can be reversed, such as the steps in the prediction stage and the steps in the control stage.

[0072] S1: Collect the current temperature of the HVAC system's temperature control environment according to the temperature measurement cycle Time_unit.

[0073] The temperature measurement cycle Time_unit is determined at the factory based on the user's application scenario, which includes room size, HVAC system heat dissipation performance, and the output power of the controlled object (i.e., the HVAC system, such as heaters, coolers, etc.). The current temperature Temp_current is detected and updated every Time_unit interval to obtain the latest temperature value of the controlled environment.

[0074] In this embodiment, the temperature measurement period Time_unit is 10s. Under the condition of no interference (e.g., without considering the influence of the ambient temperature and the aging of the HVAC system on temperature changes), the temperature 10s before or after the current temperature changes little compared to the current temperature Temp_current, generally around 0.5℃ and will not exceed 1℃. Therefore, it can meet the needs of subsequent parameter prediction and control.

[0075] S2: When entering the prediction phase, if the current temperature Temp_current is greater than the maximum allowable temperature, control the HVAC system to cool down; otherwise, control the HVAC system to heat up.

[0076] Generally, heaters are only needed to raise the room temperature when the ambient temperature is lower than the set temperature Temp_target (e.g., in winter). Therefore, HVAC systems include heaters. As shown in Figure 7, the prediction phase begins only after the prediction condition is met; the prediction condition can be the first prediction condition. The first prediction condition is the first operation of the HVAC system controller. When the HVAC system controller starts for the first time, it defaults to entering the prediction phase. It first determines the temperature range of the current temperature Temp_current. If the collected current temperature Temp_current is greater than the maximum allowable temperature, it controls or keeps the heater off to cool down; otherwise, it controls or keeps the heater on to raise the temperature.

[0077] In some embodiments, the heater can be an air conditioner with heating function. Alternatively, the heater in a heating and ventilation system can also be a hydronic heating system, which includes a boiler supplying hot water and water pipes connected to the boiler and installed in the room; the hydronic heating system is controlled to raise the room temperature. Obviously, the heater can also be other equipment with heating or heat-generating functions.

[0078] The maximum allowable temperature is the sum of the set temperature (Temp_target) and the equilibrium zone temperature (Temp_balanceLine), i.e., Temp_target + Temp_balanceLine. In the embodiment shown in Figure 1, the set temperature (Temp_target) is 20°C; obviously, the set temperature (Temp_target) can be set according to user needs. The equilibrium zone temperature (Temp_balanceLine) is 2°C, meaning the maximum allowable temperature is 22°C. The minimum allowable temperature is the difference between the set temperature (Temp_target) and the equilibrium zone temperature (Temp_balanceLine), i.e., Temp_target - Temp_target - Temp_balanceLine. Obviously, in this embodiment, the minimum allowable temperature is 18°C. The equilibrium zone temperature (Temp_balanceLine) is set at the factory and generally cannot be modified by the user. In this embodiment, the HVAC system does not include a cooler; cooling the HVAC system refers to turning off the heater, thus allowing natural cooling. This applies to HVAC systems.

[0079] S3: In the prediction phase, calculate the heating rate V_up and cooling rate V_down of the HVAC system.

[0080] As shown in Figure 8, step S3 specifically includes the following 9 steps, S31-S39:

[0081] S31: Determine whether the current temperature Temp_current is greater than or equal to the maximum allowable temperature, and then proceed to step S32 or S33.

[0082] S32: If the temperature is greater than or equal to the maximum allowable temperature, control the HVAC system to cool down, i.e., control or keep the heater off. As shown in Figure 1, the temperature will continue to rise to the maximum temperature due to thermal inertia before falling, meaning the subsequent cooling process will begin above the maximum allowable temperature.

[0083] S33: If the temperature is lower than the maximum allowable temperature, control the HVAC system to heat up, i.e., control or keep the heater running, until the collected current temperature Temp_current is greater than or equal to the maximum allowable temperature, then control the HVAC system to cool down. Specifically, every temperature measurement cycle Time_unit, the current temperature Temp_current is collected and updated, and the updated current temperature Temp_current is compared with the maximum allowable temperature.

[0084] S34: After controlling the HVAC system to cool down, determine whether the current temperature Temp_current is equal to or less than the minimum allowable temperature for the first time, and then proceed to step S35 or S36.

[0085] S35: If the temperature is equal to or first falls below the minimum allowable temperature, control the HVAC system to heat up, i.e., start the heater, and calculate the current temperature change rate Temp_current as the actual cooling rate V_down. As shown in Figure 1, the temperature will continue to drop from the minimum allowable temperature to the lowest temperature due to thermal inertia before starting to rise again.

[0086] S36: If the temperature is higher than the minimum allowable temperature, the HVAC system will continue to cool down until the current temperature (Temp_current) is equal to or first falls below the minimum allowable temperature. Then, the HVAC system will be controlled to heat up, i.e., the heater will be started, and the cooling rate (V_down) will be calculated. Specifically, every temperature measurement cycle (Time_unit), the current temperature (Temp_current) is collected and updated, and the updated current temperature (Temp_current) is compared with the minimum allowable temperature.

[0087] The calculation of the cooling rate V_down is the rate of temperature change when the temperature drops from the previous moment to the current moment for the first time after one temperature measurement cycle.

[0088] The following formula is used:

[0089] Where V_current is the rate of temperature change at any given moment, Temp_current is the current temperature, Temp_previous is the temperature at the previous moment, and the interval between the previous and current moments is equal to one temperature measurement period, Time_unit. Clearly, when calculating the cooling rate V_down, if the current temperature is exactly equal to the minimum allowable temperature, then...

[0090] S37: After controlling the HVAC system to raise the temperature, determine whether the current temperature Temp_current collected is greater than or equal to the maximum allowable temperature for the second time, and then proceed to step S38 or S39.

[0091] S38: If the temperature is greater than or equal to the maximum allowable temperature for the second time, control the HVAC system to cool down, that is, turn off the heater to cool down and calculate the current temperature change rate V_current as the actual heating rate V_up, and record the Runflag bit as 1.

[0092] S39: If the temperature is lower than the maximum allowable temperature, the HVAC system continues to heat up until the collected current temperature Temp_current is greater than or equal to the maximum allowable temperature for the second time. Then, the HVAC system is controlled to cool down, i.e., the heater is turned off, and the heating rate V_up is calculated. Specifically, every temperature measurement cycle Time_unit, the current temperature Temp_current is collected and updated, and the updated current temperature Temp_current is compared with the maximum allowable temperature.

[0093] Among them, the heating rate V_up is calculated, which is the rate of temperature change when the temperature rises from the previous moment to the current temperature for the second time after one temperature measurement cycle.

[0094] The following formula is used:

[0095] Where Temp_current is the current temperature, Temp_previous is the temperature at the previous moment, and the interval between the previous moment and the current moment is equal to one temperature measurement cycle Time_unit. Clearly, when calculating the heating rate V_up, if the current temperature equals the maximum allowable temperature for the second time, then...

[0096] During the prediction phase, the moment when the cooling rate V_down is calculated is the moment when the heating system is controlled to heat up. This can be either the moment when the current temperature equals the minimum allowable temperature during the cooling process, or the moment when the current temperature first falls below the minimum allowable temperature during the cooling process. As shown in Figure 1, when entering the prediction phase, in this embodiment, the heater is in the starting heating state. Every time a temperature measurement cycle Time_unit is reached, the current temperature Temp_current is collected and updated. When it is detected that the current temperature Temp_current is still less than 22°C (e.g., Temp_current = 21°C), the heater is kept running to continue heating until the current temperature Temp_current is detected to be equal to 22°C or exceeds 22°C for the first time (e.g., current temperature Temp_current = 22.4°C). At this point, the heater is shut down for the first time. After that, the current temperature will continue to rise to the maximum temperature due to thermal inertia before gradually decreasing.

[0097] When the current temperature Temp_current is detected to drop to or below 18°C ​​for the first time, the cooling rate V_down is calculated. In one embodiment, when the current temperature Temp_current is detected to drop to 17.8°C, and this is the first time it has fallen below 18°C, the cooling rate V_down is calculated. The current temperature at this moment is 17.8°C, and the previous temperature Temp_previous is the temperature corresponding to the moment before the current temperature of 17.8°C was collected. The heater is started for the second time while calculating the cooling rate V_down.

[0098] Since the initial conditions of the first heating process are unknown throughout the prediction phase, it is uncertain whether the prediction phase is entered due to interference during the control phase (as in the aforementioned embodiment) or because the HVAC system controller is running for the first time. Furthermore, the first heating process in the prediction phase may be affected by uncertain factors not involving the HVAC system. To reduce prediction errors, the first heating process in the prediction phase is not used to calculate the heating rate V_up. Instead, starting from the cooling phase, the cooling rate V_down is calculated first, followed by the heating rate V_up.

[0099] Similarly, during the prediction phase, since the time when the heating rate V_up is calculated (i.e., the time when the HVAC system shuts down the heaters to cool down), the current temperature Temp_current collected is not necessarily equal to the maximum allowable temperature. Instead, it represents the second time during the prediction phase that the temperature exceeds the maximum allowable temperature. Because the HVAC system has already experienced a time when it exceeds or equals the maximum allowable temperature once after startup, this second time refers to the time after the cooling rate V_down is calculated, when the temperature exceeds or equals the maximum allowable temperature again. Therefore, when the current temperature Temp_current is detected to rise below 22°C (e.g., Temp_current = 21°C), the calculation of the heating rate V_up is not triggered until the current temperature Temp_current is detected to be equal to 22°C or exceeds 22°C again (e.g., current temperature Temp_current = 22.5°C), at which point the heating rate V_up is calculated. In one embodiment, the current temperature for calculating the heating rate V_up is 22.5°C, and the previous temperature Temp_previous is the temperature corresponding to the previous moment when the current temperature was 22.5°C. While calculating the heating rate V_up, the heater is turned off for the second time to cool down.

[0100] Obviously, in other embodiments, the calculation time for the cooling rate V_down during the prediction phase can be calculated after the current temperature has been lower than or equal to the minimum allowable temperature multiple times, such as two or three times; similarly, the calculation time for the heating rate V_up can be calculated after the current temperature has been higher than or equal to the maximum allowable temperature multiple times, such as three or four times; however, if the prediction phase takes too long, it will obviously reduce the efficiency of adjusting the room temperature to the set temperature.

[0101] S4: Based on the heating rate V_up, cooling rate V_down, and amplitude error Error_target1, calculate the required heating time OnTime_balance and cooling time OffTime_balance for the HVAC system during the control phase. The heating time OnTime_balance refers to the heating time of the HVAC system, which can be the start-up time of the heater; the cooling time OffTime_balance refers to the cooling time of the HVAC system, which can be the shutdown time of the heater.

[0102] The heating time OnTime_balance is calculated using the following formula:

[0103] The cooling time OffTime_balance is calculated using the following formula:

[0104] In this embodiment, as shown in Figure 1, the amplitude error Error_target1 is 1.5℃, so the amplitude error range width Error_target is 3℃, which is twice the amplitude error Error_target1. The current temperature Temp+current is controlled within 1.5℃ above and below the set temperature Temp_target. Since the set temperature Temp_target is 20℃, the current temperature Temp_current is controlled between 18.5℃ and 21.5℃, ensuring the current temperature is within the amplitude error range. Here, 18.5℃ and 21.5℃ are the lowest and highest temperatures within the amplitude error range, respectively. The amplitude error Error_target1 can be manually set or modified according to user needs: to improve comfort, the amplitude error Error_target1 can be decreased; to increase the amplitude error Error_target1, the frequency of temperature adjustment can be reduced, thereby reducing energy consumption.

[0105] S5: When the current temperature is found to meet the first control condition, exit the prediction phase and enter the control phase. The first control condition includes the current temperature reaching the first temperature control condition; when the first control condition is met, maintain the most recent temperature control state of the HVAC system, i.e., maintain the heating or cooling state.

[0106] The first control condition is as follows: when the HVAC system is in the prediction phase, it has already triggered and calculated the heating rate V_up and cooling rate V_down, and is in a cooling state. During the cooling process after calculating the heating rate V_up, when the current temperature Temp_current is equal to the set temperature Temp_target or is lower than the set temperature Temp_target for the first time, the prediction phase is exited and the control phase is entered simultaneously. At this time, the HVAC system continues to maintain the cooling state. In this embodiment, the first temperature control condition is that the current temperature is equal to or lower than the set temperature for the first time; where, "lower than the set temperature for the first time" means that during the cooling process, the current temperature, updated according to the temperature measurement cycle, is compared with the set temperature, and the current temperature is lower than the set temperature for the first time.

[0107] As shown in Figure 1, during the prediction phase, after calculating the cooling rate V_down and heating rate V_up, the heaters of the HVAC system are shut down again, entering a cooling state. The temperature then continues to rise to its maximum and gradually decreases. When the current temperature is found to be higher than the set temperature Temp_target (e.g., 21°C), the prediction phase does not end until the current temperature Temp_current equals the set temperature Temp_target (20°C). At this point, the HVAC system exits the prediction phase and simultaneously enters the control phase. Clearly, when determining whether the current temperature Temp_current has reached the set temperature Temp_target during the cooling process, since Temp_current is only collected once every measurement cycle Time_unit, the collected current temperature Temp_current may not be exactly equal to the set temperature Temp_target; it may also be lower. Therefore, when the collected current temperature Temp_current is found to be lower than the set temperature Temp_target for the first time (e.g., 19.7°C), the prediction phase ends, and the control phase begins.

[0108] S6: After entering the control phase, based on the heating duration (OnTime_balance) and cooling duration (OffTime_balance), the continuous heating and cooling times of the HVAC system are controlled to achieve heating and cooling of the HVAC system respectively. The current temperature (Temp_current) is kept within the range of the amplitude error (Error_target1) of the set temperature (Temp_target), i.e., Temp_target - Error_target1 ≤ Temp_current ≤ Temp_target + Error_target1. Specifically, achieving heating and cooling of the HVAC system separately means alternately and cyclically controlling the heating and cooling of the HVAC system according to the heating and cooling durations.

[0109] As shown in Figure 9, step S6 specifically includes three steps: S61-S63.

[0110] S61: When the current temperature Temp_current is less than or equal to the set temperature Temp_target, exit the prediction phase and enter the control phase at the same time.

[0111] S62: After entering the control phase, maintain the cooling of the HVAC system, and the continuous cooling time is the product of the cooling duration and the first coefficient.

[0112] Taking a heater as an example, the heater is kept off, and its continuous cooling time is the product of the cooling duration and a first coefficient, i.e., the product of the heater's cooling duration OffTime_balance and the first coefficient. In this embodiment, the first coefficient is 0.5, and the continuous cooling time is 0.5 * cooling duration OffTime_balance. Obviously, the value of the first coefficient can be adjusted accordingly based on the specific application scenario of the HVAC system.

[0113] As shown in the embodiment of Figure 1, according to the calculation formula of the cooling time OffTime_balance, this cooling time is roughly equivalent to the continuous off-time of the heater when the temperature drops from 21.5℃ to 18.5℃. Similarly, according to the calculation formula of the heating time OnTime_balance, this heating time is roughly equivalent to the continuous start-up time of the heater when the temperature rises from 18.5℃ to 21.5℃. Therefore, the time required to turn off the heater from 20℃ to 18.5℃ is approximately 0.5 times the cooling time OffTime_balance.

[0114] S63: Then control the HVAC system to alternate between heating and cooling. The continuous heating time is the product of the heating duration and the second coefficient, and the continuous cooling time is the product of the cooling duration and the third coefficient.

[0115] In this embodiment, both the second and third coefficients are 1. As shown in Figure 1, before entering the control phase, the room temperature has already dropped to 20°C, or is close to 20°C. Obviously, the temperature measurement cycle can be adjusted to keep the time of entering the control phase close to the set temperature. During the control phase, the heater remains off. After the first 0.5 * cooling time OffTime_balance, before the room temperature reaches the minimum temperature of 18.5℃, the heater is activated to raise the temperature. The temperature will first drop to near the minimum temperature of 18.5℃ before starting to rise again. The heater is then activated and maintains the temperature rise for one time onTime_balance. Before the temperature reaches the maximum temperature of 21.5℃, the heater is turned off and maintains the temperature drop for one time offTime_balance. The temperature will then first rise to near the maximum temperature of 21.5℃ before starting to drop again. The heater is then activated again and maintains the temperature rise for one time onTime_balance. This cycle of starting and turning off the heater continues, ensuring that the current room temperature Temp_current remains within the amplitude error Error_target1 range of the set temperature Temp_target, i.e., between 18.5℃ and 21.5℃. Clearly, the values ​​of the second and third coefficients can be adjusted according to the specific application scenario of the HVAC system.

[0116] It should be noted that during the control phase, although the room temperature may drop to below 18.5°C after the temperature drops to below 20°C and the heater is kept off for 0.5 times the cooling time OffTime_balance, the difference in perceived temperature is negligible due to the small error.

[0117] This disclosure also provides a heating and ventilation system controller that employs the above-described temperature control method for heating and ventilation systems.

[0118] In another embodiment of this disclosure, as shown in Figure 2, the difference from the aforementioned embodiment lies in the different process after calculating the heating rate V_up and the cooling rate V_down. Specifically, when the current temperature is found to meet the second control condition, the system exits the prediction phase and enters the control phase. Meeting the second control condition includes the current temperature reaching a second temperature control condition; when the second control condition is met, the system simultaneously maintains the most recent temperature control state of the HVAC system, i.e., maintains either a heating or cooling state.

[0119] In this embodiment, the second temperature control condition is that during the cooling process after calculating the heating rate V_up, the current temperature is equal to or less than the sum of the set temperature and the amplitude error Error_target1 for the first time; wherein, the first time less than the sum of the set temperature and the amplitude error Error_target1 means that during the cooling process, the current temperature updated according to the temperature measurement cycle is compared with the set temperature, and the current temperature is less than the sum of the set temperature and the amplitude error Error_target1 for the first time.

[0120] The specific steps for distinguishing are as follows:

[0121] S5: Control the HVAC system to cool down until the current temperature Temp_current is less than or equal to the sum of the set temperature and the amplitude error Error_target1, that is, when it is equal to or less than 21.5℃ for the first time, exit the prediction stage and enter the control stage.

[0122] S61: Keep the HVAC system cooled down, and the cooling time is the product of the cooling duration OffTime_balance and the first coefficient.

[0123] S62: Then control the HVAC system to alternate between heating and cooling. The heating time is the product of the heating duration OnTime_balance and the second coefficient, and the cooling time is the product of the cooling duration OffTime_balance and the third coefficient.

[0124] The first, second, and third coefficients are all 1.

[0125] In another embodiment of this disclosure, as shown in Figure 3, the difference from the aforementioned embodiments lies in the different processes after calculating the heating rate V_up and cooling rate V_down. Specifically, when the current temperature is found to meet the third control condition, the system exits the prediction phase and enters the control phase. Meeting the third control condition includes the current temperature reaching the third temperature control condition; when the third control condition is met, the most recent temperature control state of the HVAC system is changed, i.e., from a cooling state to a heating state.

[0126] In this embodiment, the third temperature control condition is that during the cooling process after calculating the heating rate V_up, the current temperature is equal to or less than the difference between the set temperature and the amplitude error Error_target1 for the first time; wherein, the first time less than the difference between the set temperature and the amplitude error Error_target1 means that during the cooling process, the current temperature updated according to the temperature measurement cycle is compared with the set temperature, and the current temperature is less than the difference between the set temperature and the amplitude error Error_target1 for the first time.

[0127] The specific steps for distinguishing are as follows:

[0128] S5: Control the HVAC system to cool down until the current temperature Temp_current is less than or equal to the difference between the set temperature and the amplitude error Error_target1, that is, when it is equal to or less than 18.5℃ for the first time, exit the prediction stage and enter the control stage.

[0129] S61: Control and maintain the heating system to heat up, with the heating time being the product of the heating duration OnTime_balance and the first coefficient.

[0130] S62: Then control the HVAC system to alternate between cooling and heating. The continuous cooling time is the product of the cooling duration OffTime_balance and the second coefficient, and the continuous heating time is the product of the heating duration OnTime_balance and the third coefficient.

[0131] The first, second, and third coefficients are all 1.

[0132] In another embodiment of this disclosure, the difference from the aforementioned embodiments lies in that, during the process of controlling the heater's operating state according to the heating time OnTime_balance and cooling time OffTime_balance, changes in the external ambient temperature, such as daytime and nighttime temperature variations, winter and summer temperature variations, or power reduction due to aging of the cooler / heater, can affect the temperature control of the HVAC system. Therefore, after entering the control phase, when the second prediction condition is met, the system exits the control phase and re-enters the prediction phase to improve the system's anti-interference capability and control accuracy. At this time, the prediction condition is the second prediction condition.

[0133] Preferably, the second prediction condition includes the following conditions:

[0134] During the control phase, when the peak value of the current temperature Temp_current, Temp_top, is continuously collected and exceeds the maximum allowable temperature for the first set number of times, the control phase is exited and the prediction phase is re-entered.

[0135] During the operation of the HVAC system, specifically in the control phase, the peak value of the current temperature, Temp_top, is determined, confirmed, and stored. In the control phase, the determination and storage of the peak value, Temp_top, can be further restricted. It can be determined and stored only when the current temperature, Temp_current, is greater than the sum of the set temperature, Temp_target, and the amplitude error, Error_target1. The first set number of times is three, as shown in Figure 9. The second prediction condition for exiting the control phase is as follows: when three consecutive peak values ​​are greater than the maximum allowable temperature, the control phase exits from the time point of the third peak value acquisition and enters the prediction phase, setting the run flag of the control phase to 0; otherwise, after waiting for one temperature measurement cycle, Time_unit, the system continues to determine whether the peak value, Temp_top, of the current temperature meets the second prediction condition of the control phase. In one embodiment, the peak value is determined as follows: A, B, and C are the current temperatures (Temp_current) collected by any three consecutive temperature measurement cycles (Time_unit). When it is determined that the temperature value at point C is less than the temperature value at point B, it is then determined whether the temperature value at point A is also less than the temperature value at point B. If the temperature values ​​at both points A and C are less than the temperature value at point B, then the temperature value at point B is determined to be the peak value. The above method for determining the peak value is one embodiment; obviously, there are other methods as well.

[0136] During the alternating heating and cooling control process in the control phase, if the Runflag flag is not 1, it indicates that the second prediction condition of the control phase has been met, and the process exits the control phase and re-enters the prediction phase. If the Runflag flag is 1, the process remains in the control phase and continues to alternately control heating and cooling. The first set number of times and the Runflag flag can be set as needed.

[0137] As shown in Figure 4, when interference is encountered during the control phase but the second prediction condition is not yet met (i.e., the collected room temperature (current temperature) is greater than 21.5℃ but less than the maximum allowable temperature of 22℃), the heater is still started and stopped according to the control process described in the previous embodiment because the temperature error is within a controllable range. When the interference causes the temperature error to gradually exceed the controllable range (i.e., the peak value of the collected room temperature is greater than the maximum allowable temperature of 22℃ three times consecutively), the control phase is exited and the prediction phase begins. At this time, the heater is in the off state. Subsequently, if the collected current temperature Temp_current is still greater than or equal to 18.5℃, since the heater is in the off state, it is only necessary to keep the heater off for cooling. When the collected current temperature Temp_current equals 18℃ or is less than 18℃ for the first time, the cooling rate V_down is calculated, and the heater is started for heating. Then, when the collected current temperature Temp_current equals 22℃ or is greater than 22℃ for the first time, the heating rate V_up is calculated. The subsequent prediction and control phases are the same as in the previous embodiment and will not be described again here.

[0138] After re-entering the prediction phase, the new heating rate V_up and the new cooling rate V_down under the current environment will be recalculated, thus obtaining new heating and cooling durations to ensure that the subsequent control phases are adapted to the changing environment, thereby making the subsequent temperature control more accurate and the temperature control consistency better.

[0139] In yet another embodiment of this disclosure, the difference from the foregoing embodiments is that, preferably, the second prediction condition includes the following conditions:

[0140] During the control phase, if the valley value of the current temperature Temp_current is continuously collected and is less than the minimum allowable temperature up to the second set number of times, the control phase will be exited and the prediction phase will be re-entered.

[0141] As shown in Figure 9, in this embodiment, the second set number of times is three. When the valley value of the current temperature Temp_current is less than the minimum allowable temperature for three consecutive times, the control phase will be exited and the prediction phase will be entered, and the run flag bit Runflag of the control phase will be set to 0; otherwise, after waiting for one temperature measurement cycle Time_unit, it will continue to determine whether the current temperature meets the second prediction condition of the control phase.

[0142] Since the temperature enters a heating state after three consecutive measurements of the valley value of the current temperature Temp_current being less than the minimum allowable temperature, the temperature will gradually rise. Therefore, after re-entering the prediction stage, the heating rate V_up can be calculated first and then the cooling rate V_down. Of course, it is also possible that after the temperature is in a downward trend, the cooling rate V_down can be calculated first and then the heating rate V_up can be calculated.

[0143] During the alternating heating and cooling control process in the control phase, if the Runflag flag is not detected to be 1, it indicates that the second prediction condition of the control phase is met, and the control phase is exited and the prediction phase is re-entered; if the Runflag flag is detected to be 1, the alternating heating and cooling control in the control phase continues. The second set number of times and the Runflag flag can be set as needed.

[0144] During the operation of the HVAC system, the current temperature valley value (Temp_button) is determined, confirmed, and stored. In the control phase, the determination and storage of the valley value can be further limited; it can be determined and stored only when the current temperature is less than the difference between the set temperature and the amplitude error (Error_target1). The specific method for determining the valley value (Temp_button) corresponding to exiting the control phase is as follows: when three consecutive valley values ​​are all less than the minimum allowable temperature, the control phase exits from the time point of the third valley value acquisition and enters the prediction phase. In one embodiment, the valley value is determined as follows: A1, B1, and C1 are the current temperatures (Temp_current) collected by any three consecutive temperature measurement cycles (Time_unit). When it is determined that the temperature value at point C1 is greater than the temperature value at point B1, it is determined whether the temperature value at point A1 is also greater than the temperature value at point B1. If the temperature values ​​at points A1 and C1 are both greater than the temperature value at point B1, then the temperature value at point B1 is determined to be the valley value (Temp_button). The above method for determining the valley value (Temp_button) is one embodiment; obviously, there are other determination methods.

[0145] In yet another embodiment of this disclosure, the difference from the foregoing embodiments is that, preferably, the second prediction condition includes the following conditions:

[0146] During the control phase, the current error Error_current is obtained. When the current error Error_current is greater than the product of the amplitude error Error_target1 and the threshold coefficient, the control phase is exited and the prediction phase is re-entered.

[0147] As shown in Figure 9, in this embodiment, the threshold coefficient is 3. During the control phase, when controlling the continuous working time or continuous off time of the heater, the current error Error_current is obtained in real time. When the current error Error_current is greater than 3 * amplitude error Error_target1, the run flag bit Runflag of the control phase is set to 0; otherwise, after waiting for one temperature measurement cycle Time_unit, it continues to determine whether the current error of the heater meets the second prediction condition of the control phase.

[0148] During the alternating heating and cooling control process in the control phase, if the Runflag flag is not 1, it indicates that the second prediction condition of the control phase is met, and the control phase is exited and the prediction phase is re-entered; if the Runflag flag is 1, the alternating heating and cooling control in the control phase continues. The threshold coefficient and the Runflag flag can be set according to the specific application scenario.

[0149] The current error, Error_current, is calculated using the following formula:

[0150] Error_current=Temp_top-Temp_button

[0151] Wherein, the peak value Temp_top is the highest temperature when the current temperature Temp_current is greater than the maximum allowable temperature each time it is collected; Temp_button is the previous lowest temperature corresponding to each time the current temperature Temp_current is greater than the maximum allowable temperature. As shown in Figure 5, during the control phase, the highest and lowest temperatures of the HVAC system are collected and stored in real time. Each highest temperature is recorded as the peak value Temp_top, and each lowest temperature is recorded as the valley value Temp_button. When the calculated current error Error_current is greater than 3 * amplitude error Error_target1, the moment corresponding to the peak value Temp_top of the current error Error_current is the moment of exiting the control phase and re-entering the prediction phase. In the control phase, the method for determining the corresponding peak value Temp_top and valley value Temp_button can be the same as the method in the aforementioned embodiment. Here, Figure 5 is only used as a schematic diagram of the temperature change trend and the nodes of the prediction and control phases.

[0152] In another embodiment of this disclosure, the difference from the aforementioned embodiments lies in that the calculation of the current error Error_current is further limited by specific conditions. The current error Error_current is only calculated and obtained when these conditions are met. Specifically, the calculation of Error_current only occurs when the current temperature Temp_current is less than the difference between the set temperature Temp_target and the amplitude error Error_target1, or when the current temperature Temp_current is greater than the sum of the set temperature Temp_target and the amplitude error Error_target1. This is because when the current temperature Temp_current is within the range of the amplitude error Error_target1 of the set temperature Temp_target, the current error Error_current will theoretically not exceed the threshold coefficient of the amplitude error Error_target1, thus reducing data redundancy and improving system operating efficiency.

[0153] In another embodiment of this disclosure, the difference from the foregoing embodiments is that the HVAC system includes a heater and a cooler. When heating up, the heater is activated while the cooler is off; the heating duration is the same as the heater's activation duration. When cooling down, the heater is turned off for natural cooling, and the cooler is activated for active cooling; the cooling duration is the same as both the heater's shutdown duration and the cooler's activation duration. The cooling rate in this embodiment is significantly greater than that in the foregoing embodiments, and the heater's shutdown duration is shorter. In this case, the corresponding HVAC system is called HVACR.

[0154] In another embodiment of this disclosure, the difference from the aforementioned embodiment lies in the different application scenario of the HVAC system. Specifically, the HVAC system controller operates when the ambient temperature exceeds the set temperature Temp_target (e.g., in summer, when the heater is not running). In this case, the cooler is controlled to lower the room temperature. The HVAC system includes a heater and a cooler. Therefore, step S2 is:

[0155] When entering the prediction phase, if the current temperature Temp_current is less than the minimum allowable temperature, the HVAC system is controlled to heat up, that is, the cooler is turned off for natural heating and the heater is in the off state; otherwise, the HVAC system is controlled to cool down, that is, the cooler is controlled or kept running for cooling and the heater is in the off state.

[0156] As shown in Figure 11, when entering the prediction phase, the current temperature Temp_current is first determined. When the current temperature Temp_current is less than or equal to the minimum allowable temperature, the HVAC system is controlled to heat up. The temperature will continue to decrease from the minimum allowable temperature to the lowest temperature before starting to rise again. That is, the subsequent heating process starts below the minimum allowable temperature. After the HVAC system heats up, if the current temperature Temp_current is greater than or equal to the maximum allowable temperature, the heating rate V_up at the current moment is calculated and the HVAC system is controlled to cool down. The temperature will continue to rise from the maximum allowable temperature to the highest temperature before starting to fall again. After the HVAC system cools down, if the current temperature Temp_current is less than or equal to the minimum allowable temperature for the second time, the cooling rate V_down at the current moment is calculated and the HVAC system is controlled to heat up again.

[0157] As shown in Figure 10, during the prediction phase, the required heating time (OnTime_balance) and cooling time (OffTime_balance) of the HVAC system are calculated based on the heating rate (V_up), cooling rate (V_down), and amplitude error (Error_target1). Simultaneously, after the cooling rate (V_down) calculation time, the HVAC system is controlled to heat up until the current temperature (Temp_current) satisfies the fourth control condition. At this point, the prediction phase ends and the control phase begins. Although the HVAC system continues to heat up naturally after the cooling rate (V_down) calculation time (i.e., the cooler remains off), due to thermal inertia, the temperature will continue to drop to the minimum temperature before rising again. Every temperature measurement cycle (Time_unit) the current temperature (Temp_current) is collected and updated until it satisfies the fourth temperature control condition. Then, the HVAC system continues heating up (cooler off) and enters the control phase.

[0158] The fourth control condition is as follows: When the HVAC system is in the prediction phase, the heating rate V_up and cooling rate V_down have been triggered and calculated, and the system is in a heating state. During the heating process after calculating the cooling rate V_down, when the current temperature Temp_current is equal to or exceeds the set temperature Temp_target for the first time, the prediction phase ends and the system simultaneously enters the control phase. At this time, the HVAC system continues to maintain the heating state. The fourth control condition includes the current temperature reaching the fourth temperature control condition.

[0159] As shown in Figure 11, in this embodiment, the fourth temperature control condition is that during the heating process after calculating the cooling rate V_down, the current temperature Temp_current is equal to or greater than the set temperature Temp_target for the first time. Here, "greater than the set temperature for the first time" refers to the moment when, during the heating process, the current temperature, updated according to the temperature measurement cycle, is first greater than the set temperature when compared with the set temperature.

[0160] After entering the control phase, the HVAC system is kept heating up for a duration equal to the product of the first coefficient and the heating duration OnTime_balance. Then, the HVAC system is controlled to alternate between cooling and heating up. The cooling duration is equal to the product of the cooling duration OffTime_balance and the second coefficient, while the heating duration is equal to the product of the heating duration OnTime_balance and the third coefficient. The cooler is then started and stopped in a cycle to keep the current temperature Time_current within the amplitude error Error_target1 of the set temperature Time_targte.

[0161] Taking the use of an HVAC system in summer as an example, the heating time OffTime_balance refers to the time the cooler is turned off and kept off, i.e., the natural heating time; the cooling time OffTime_balance refers to the time the cooler is continuously turned on and kept on, i.e., the cooling time. The calculation of heating time OffTime_balance and cooling time OffTime_balance is the same as in the previous embodiment, and the values ​​of the first coefficient, the second coefficient, and the third coefficient are also the same as in the previous embodiment.

[0162] Obviously, the control conditions can be adjusted as needed. For example, when the current temperature (Time_current) meets the fifth temperature control condition, the system can exit the prediction phase and enter the control phase simultaneously. For instance, the fifth temperature control condition is: during the heating process after calculating the cooling rate (V_down), when the current temperature (Temp_current) is equal to or greater than the sum of the set temperature (Temp_target) and the amplitude error (Error_target1) for the first time, the system enters the control phase. It then controls and maintains the HVAC system to cool down for a duration equal to the product of the cooling duration (OffTime_balance) and the first coefficient. Next, the system alternates between heating up and cooling down, with the heating duration equal to the product of the heating duration (OnTime_balance) and the second coefficient, and the cooling duration equal to the product of the cooling duration (OffTime_balance) and the third coefficient. This cycle of starting and stopping the cooler continues. The first, second, and third coefficients are all equal to 1.

[0163] For example, when the current temperature Temp_current meets the sixth temperature control condition, the system exits the prediction phase and enters the control phase. The sixth temperature control condition is that during the heating process after calculating the cooling rate V_down, the current temperature Temp_current equals or for the first time exceeds the difference between the set temperature Temp_target and the amplitude error Error_target1. In this case, after entering the control phase, the HVAC system is kept heating up for a duration equal to the product of the heating duration and the first coefficient. Then, the HVAC system is controlled to alternate between cooling and heating up, with the cooling duration equal to the product of the cooling duration and the second coefficient, and the heating duration equal to the product of the heating duration and the third coefficient. The first, second, and third coefficients are all equal to 1.

[0164] This disclosure is not limited to the above-described preferred embodiments. Anyone can derive other products in various forms under the guidance of this disclosure. However, regardless of any changes in shape or structure, any technical solution that is the same as or similar to this disclosure falls within the protection scope of this disclosure. Industrial applicability

[0165] The temperature control method and controller for the HVAC system disclosed herein control the continuous heating time and continuous cooling time of the HVAC system, allowing for an acceptable temperature difference, so that the current temperature can be dynamically stabilized within the allowable amplitude error of the set temperature, reducing the number of temperature adjustments and power consumption, while making the temperature control accuracy controllable and greatly improving the consistency of temperature control.

Claims

1. A temperature control method for a heating, ventilation, and air conditioning system, characterized in that, Includes the following steps: Collect the current temperature of the temperature-controlled environment of the HVAC system according to the temperature measurement cycle; Entering the prediction phase, the cooling rate and heating rate of the HVAC system are calculated; The cooling rate is calculated as follows: Calculate the rate of temperature change when the temperature drops from the previous temperature to the current temperature less than or equal to the minimum allowable temperature within a temperature measurement cycle, and use this as the cooling rate. The heating rate is calculated as follows: The rate of temperature change from the previous moment to the current temperature being greater than or equal to the maximum allowable temperature is calculated within a temperature measurement cycle and is taken as the heating rate. Based on the heating rate, the cooling rate, and the amplitude error, calculate the heating time and cooling time required for the HVAC system, respectively. Upon exiting the prediction phase, it simultaneously enters the control phase; After entering the control phase, the continuous heating time and continuous cooling time of the HVAC system are controlled according to the heating time and cooling time, so as to realize the heating and cooling of the HVAC system respectively, and keep the current temperature within the amplitude error of the set temperature.

2. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 1, characterized in that: The heating time is calculated as follows: The cooling time is calculated as follows: 其 In this context, OffTime_balance is the heating time, OffTime_balance is the cooling time, V_up is the heating rate, V_down is the cooling rate, and Error_target is the amplitude error range width, which is twice the amplitude error.

3. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 1, characterized in that: The prediction phase, which calculates the cooling rate and heating rate of the HVAC system, includes the following steps: Determine if the current temperature is greater than or equal to the maximum allowable temperature. If it is, control the HVAC system to cool down. After the HVAC system is cooled down, it is determined whether the current temperature is less than or equal to the minimum allowable temperature. If it is less than or equal to the minimum allowable temperature, the HVAC system is heated up, and the cooling rate is calculated. After the HVAC system is heated, it is determined whether the current temperature is greater than or equal to the maximum allowable temperature for the second time. If it is greater than or equal to the maximum allowable temperature, the HVAC system is controlled to cool down, and the heating rate is calculated.

4. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 1, characterized in that: The prediction phase, which calculates the cooling rate and heating rate of the HVAC system, includes the following steps: Determine if the current temperature is less than or equal to the minimum allowable temperature. If it is, control the HVAC system to heat up. After the HVAC system is heated, it is determined whether the current temperature is greater than or equal to the maximum allowable temperature. If it is greater than or equal to the maximum allowable temperature, the HVAC system is controlled to cool down, and the heating rate is calculated. After the HVAC system is cooled down, it is determined whether the current temperature is less than or equal to the minimum allowable temperature for the second time. If it is less than or equal to the minimum allowable temperature, the HVAC system is heated up, and the cooling rate is calculated.

5. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 3, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the first control condition, the prediction phase is exited and the control phase is entered simultaneously. The first control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to the set temperature or is lower than the set temperature for the first time.

6. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 3, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the second control condition, the prediction phase is exited and the control phase is entered simultaneously. The second control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to or less than the sum of the set temperature and the amplitude error for the first time.

7. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 3, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the third control condition, the prediction phase is exited and the control phase is entered simultaneously. The third control condition is that, during the cooling process after calculating the heating rate, when the current temperature is equal to or less than the difference between the set temperature and the amplitude error for the first time.

8. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 4, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the fourth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously. The fourth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to the set temperature or exceeds the set temperature for the first time.

9. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 4, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the fifth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously. The fifth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to or greater than the sum of the set temperature and the amplitude error for the first time.

10. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 4, characterized in that: The process of exiting the prediction phase and entering the control phase simultaneously includes the following steps: when the current temperature is collected and meets the sixth temperature control condition, the prediction phase is exited and the control phase is entered simultaneously. The sixth temperature control condition is that, during the heating process after calculating the cooling rate, when the current temperature is equal to or greater than the difference between the set temperature and the amplitude error for the first time.

11. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 5-10, characterized in that: After entering the control phase; The heating and ventilation system is controlled to cool down, and the continuous cooling time is the product of the cooling duration and a first coefficient; then the heating and ventilation system is controlled to alternate between heating and cooling, and the continuous heating time is the product of the heating duration and a second coefficient, and the continuous cooling time is the product of the cooling duration and a third coefficient.

12. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 5-10, characterized in that: After entering the control phase; The heating and ventilation system is controlled to heat up, and the heating time is the product of the heating duration and a first coefficient; then the heating and ventilation system is controlled to alternate between cooling and heating, and the cooling time is the product of the cooling duration and a second coefficient, and the heating time is the product of the heating duration and a third coefficient.

13. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 11 or 12, characterized in that: The HVAC system includes a heater. When heating up, the heater is activated for the same duration as the heater's activation time. When cooling down, the heater is deactivated for the same duration as the heater's deactivation time.

14. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 11 or 12, characterized in that: The HVAC system includes a heater and a cooler. When heating up, the heater is activated and the cooler is turned off. The heating time is the same as the heater activation time. When cooling down, the heater is turned off for natural cooling and the cooler is activated for active cooling. The cooling time is the same as the heater shutdown time and the cooler activation time.

15. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 1-14, characterized in that, It also includes the following steps: The prediction phase only begins after the prediction conditions are met. The prediction condition is the first prediction condition, which is the first operation of the HVAC system controller.

16. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 1-14, characterized in that, It also includes the following steps: The prediction condition is a second prediction condition, which includes one of the following conditions: During the control phase, when the peak value of the current temperature is continuously collected and exceeds the maximum allowable temperature for a first set number of times; During the control phase, when the valley value of the current temperature is continuously collected and is less than the minimum allowable temperature for a second set number of times; During the control phase, the current error is obtained, and the current error is greater than the product of the amplitude error and the threshold coefficient.

17. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 1-16, characterized in that, The maximum allowable temperature is the sum of the set temperature and the equilibrium zone temperature, and the minimum allowable temperature is the difference between the set temperature and the equilibrium zone temperature.

18. The temperature control method for a heating, ventilation, and air conditioning system as described in any one of claims 11-14, characterized in that, The first coefficient is 0.5, and the second and third coefficients are both 1.

19. The temperature control method for a heating, ventilation, and air conditioning system as described in claim 16, characterized in that, The first set number of times and the second set number of times are both 3, and the threshold coefficient is 3.

20. A heating, ventilation, and air conditioning (HVAC) system controller, characterized in that: The temperature control method for the HVAC system as described in any one of claims 1-19 is adopted.

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