Air conditioner energy demand control method

Abstract

The invention relates to the technical field of air conditioners, and discloses an air conditioner energy demand control method which is applied to an air conditioning system comprising an indoor unit and an outdoor unit and comprises the steps that at least one state parameter representing the operation demand of the air conditioning system is obtained in the indoor unit, and the energy demand of the air conditioner is determined based on the state parameter; calculating and generating a quantized control instruction for adjusting the operation frequency of a variable-frequency compressor in the outdoor unit; the indoor unit encodes the control instruction into the duty ratio of one switching signal in a preset communication period, and different values of the quantization control instruction correspond to different duty ratio values; a switching signal bearing duty ratio information is transmitted to the outdoor unit from the indoor unit; receiving and measuring the duty ratio of the switching signal in a preset communication period in the outdoor unit, and decoding a quantized control instruction corresponding to the measured duty ratio based on the measured duty ratio; and the outdoor unit adjusts the operation frequency of the inverter compressor according to the decoded quantized control instruction.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to a method for controlling the functions of an air conditioner. Background Technology

[0002] With the worsening global warming and energy crisis, energy conservation and emission reduction have become a focus of attention across all industries, especially in high-energy-consuming sectors. Air conditioners, as necessities of modern life, are increasingly highlighting their enormous energy consumption. Statistics show that air conditioning energy consumption accounts for 20% to 40% of total building energy consumption, and puts enormous pressure on the power grid during hot seasons. Therefore, improving the energy efficiency of air conditioners and achieving energy-saving operation has become a top priority in current air conditioning technology research and development.

[0003] Modern inverter air conditioners adjust their cooling / heating output by regulating the compressor's operating frequency to match the actual room heat load, thus achieving precise temperature control and energy-saving operation. Compared to traditional fixed-frequency air conditioners, inverter control avoids the energy consumption surges caused by frequent start-stop cycles and keeps the compressor operating in a relatively efficient speed range for most of the operating time. To achieve this refined inverter control, the indoor unit needs to calculate the real-time energy demand based on changes in the indoor environment and user settings, and effectively transmit the corresponding compressor speed adjustment commands to the outdoor unit responsible for execution.

[0004] In existing air conditioning control systems, there are two main technical approaches to achieve communication between the indoor and outdoor units and control of the compressor speed:

[0005] The first type is based on advanced digital communication buses, typically using serial communication technologies such as RS-485 or CAN bus. This type of solution can transmit complex digital messages over cables via specialized communication protocols, carrying a large amount of information, exhibiting strong anti-interference capabilities, and accurately transmitting large amounts of data such as inverter commands, operating modes, and fault information calculated by the indoor unit. Upon receiving these digital commands, the outdoor unit can directly drive the inverter to achieve precise speed regulation. However, this type of solution has significant drawbacks: First, it requires dedicated communication transceiver chips and more complex microcontrollers (MCUs) on the indoor and outdoor unit control boards, and necessitates the development and maintenance of a complex software communication protocol stack, significantly increasing the hardware and R&D costs of the control system. Second, air conditioning manufacturers typically use their own proprietary, undisclosed communication protocols, leading to incompatibility between indoor and outdoor unit systems of different brands or models. This creates a technical barrier, limiting product versatility and interchangeability, and hindering market promotion, retrofitting of existing equipment, or flexible user configuration of indoor and outdoor units.

[0006] The second approach is based on traditional, simple switching signals. For example, a 24V AC voltage signal is used to control the basic operating status of the outdoor unit (such as start-stop) via a relay. The advantages of this approach are: extremely simple circuit structure, very low hardware cost, high system reliability, and due to its simplicity, high versatility and interchangeability; products from different manufacturers can often achieve basic interlocking control through simple wiring. However, this approach has a fatal flaw: a simple switching signal can essentially only transmit binary information of "on" or "off," with extremely limited information capacity. It cannot carry the multi-level, quantified compressor speed adjustment commands calculated by complex algorithms for the indoor unit. Therefore, air conditioning systems using this communication method typically only achieve simple constant-speed start-stop control for the compressor, or at most, a few preset frequency switches (such as high frequency and low frequency), unable to make continuous or multi-level precise adjustments based on subtle changes in room heat load. This results in the compressor not operating at its optimal efficiency point for most of the operating time, leading to low energy efficiency. Furthermore, the inability to achieve smooth energy output regulation easily causes indoor temperature fluctuations, affecting user comfort.

[0007] In summary, existing technologies face a significant bottleneck in communication and energy demand control between indoor and outdoor air conditioning units: powerful digital communication solutions are expensive and have poor compatibility; low-cost on / off control solutions are too simplistic and cannot achieve precise variable frequency control. The market urgently needs a solution that can overcome the information capacity limitations of traditional on / off control methods while maintaining their low cost and high versatility, enabling multi-level, quantitative, and precise adjustment of compressor speed. How to "encode" and transmit complex control information far exceeding its inherent dimensions on the simplest 24V on / off signal medium is a key technical challenge that urgently needs to be solved in the field of air conditioning energy demand control. Summary of the Invention

[0008] This invention provides an air conditioning energy demand control method. Based on the low-cost and highly versatile traditional air conditioning indoor and outdoor unit communication hardware, it breaks through the limitations of its information transmission capabilities and realizes multi-level, quantitative and precise control of the operating frequency of the outdoor unit's inverter compressor by the indoor unit. This ensures user comfort while maximizing the optimization of the air conditioning system's energy efficiency and reducing operating energy consumption.

[0009] This invention provides an air conditioning function control method, applied to an air conditioning system including an indoor unit and an outdoor unit, comprising:

[0010] S1: Obtain at least one state parameter characterizing the operating requirements of the air conditioning system in the indoor unit, and calculate and generate a quantitative control command based on the state parameter to adjust the operating frequency of the variable frequency compressor in the outdoor unit.

[0011] S2: The indoor unit encodes the control command into the duty cycle of a switch signal within a preset communication cycle, where different values ​​of the quantized control command correspond to different duty cycle values;

[0012] S3: The switch signal carrying duty cycle information is transmitted from the indoor unit to the outdoor unit;

[0013] S4: Receive and measure the duty cycle of the switch signal within a preset communication cycle in the outdoor unit, and decode the corresponding quantized control command based on the measured duty cycle value;

[0014] S5: The outdoor unit adjusts the operating frequency of the inverter compressor based on the decoded quantized control commands.

[0015] Preferably, in step S1, the state parameters include indoor ambient temperature and set temperature, and the calculation and generation of quantified control commands includes:

[0016] The temperature deviation is calculated based on the difference between the indoor ambient temperature and the set temperature.

[0017] Energy requirement parameters are calculated based on temperature deviation;

[0018] The control command is determined based on the energy demand parameter.

[0019] Preferably, the energy requirement parameters calculated based on temperature deviation include:

[0020] Q1=Q2+4*(△t1-△t2)+r*(△t1+△t2)*40 / f

[0021] Where Q1 represents the energy demand parameter of the current cycle; Δt1 represents the temperature deviation of the current cycle; Δt2 represents the temperature deviation of the previous cycle; Q2 represents the energy demand parameter of the previous cycle; r is the integral coefficient; and f is the value function.

[0022] Preferably, the integral coefficient r and the value function f are determined based on the absolute value of the current period temperature deviation Δt1, specifically as follows:

[0023] When |△t1|≥10, f=5, r=1;

[0024] When 0.5 ≤ |△t1| < 10, f = 60 - (|△t1| - 1) × 55 / 9, r = 1;

[0025] When |△t1|<0.5, r=0.

[0026] Preferably, the quantized control command is a compressor frequency increment, determined according to the numerical range of the energy demand parameter Q1, including +6Hz, +4Hz, +2Hz, 0Hz, -2Hz, -4Hz and -6Hz.

[0027] Preferably, in step S2, the correspondence between encoding the control command into duty cycles is as follows:

[0028] A compressor frequency increase of -6Hz corresponds to a duty cycle of 20%.

[0029] A compressor frequency increase of -4Hz corresponds to a duty cycle of 30%.

[0030] A compressor frequency increase of -2Hz corresponds to a duty cycle of 40%.

[0031] A 0Hz increase in compressor frequency corresponds to a 50% duty cycle;

[0032] A compressor frequency increase of +2Hz corresponds to a duty cycle of 60%.

[0033] A compressor frequency increase of +4Hz corresponds to a duty cycle of 70%.

[0034] A compressor frequency increase of +6Hz corresponds to a duty cycle of 80%.

[0035] Preferably, in step S3, the switching signal is a 24V AC voltage signal, which is controlled by the on / off state of a relay, and the switching signal is transmitted between the indoor unit and the outdoor unit through a single signal line.

[0036] Preferably, in step S4, before transmitting the switch signal carrying duty cycle information, the indoor unit sends a synchronization signal to the outdoor unit. The synchronization signal is a continuous switch signal with a preset duration, used to align the time axes of the indoor unit and the outdoor unit.

[0037] The synchronization signal is a continuous ON signal lasting 30 seconds. After the synchronization signal ends, the indoor unit and the outdoor unit simultaneously start a 60-second communication cycle timer.

[0038] After one communication cycle ends, the system enters a 120-second waiting period before starting the next control and adjustment cycle.

[0039] Preferably, the method for calculating the temperature deviation is related to the air conditioning operating mode:

[0040] In cooling mode, the temperature deviation Δt1 = T1 - Ts;

[0041] In heating mode, the temperature deviation Δt1 = Ts - T1;

[0042] Where T1 is the indoor ambient temperature and Ts is the set temperature.

[0043] Preferably, in step S5, adjusting the operating frequency of the variable frequency compressor includes:

[0044] Adjusted frequency = current operating frequency + frequency increment;

[0045] Calculate the new operating frequency and control the variable frequency compressor to operate at the new operating frequency.

[0046] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0047] This invention discloses an air conditioner energy demand control method that breaks through the limitation of traditional switch signals, which can only transmit binary information, enabling them to carry multi-level, quantified, and complex control commands. While maintaining the low cost and high versatility advantages of the 24V switch signal hardware solution, it achieves a refined control effect that previously required complex digital communication. Based on a universal switch signal interface, it improves the compatibility and interchangeability between indoor and outdoor units of different brands and models of air conditioners. Through multi-level quantized control, the compressor can more accurately match actual energy demand, improving the system's energy efficiency ratio and user comfort. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of an air conditioning function control method provided in an embodiment of the present invention. Detailed Implementation

[0049] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0050] like Figure 1 As shown, this application provides an air conditioning function control method, applied to an air conditioning system including an indoor unit and an outdoor unit, comprising:

[0051] S1: Obtain at least one state parameter characterizing the operating requirements of the air conditioning system in the indoor unit, and calculate and generate a quantitative control command based on the state parameter to adjust the operating frequency of the variable frequency compressor in the outdoor unit.

[0052] S2: The indoor unit encodes the control command into the duty cycle of a switch signal within a preset communication cycle, where different values ​​of the quantized control command correspond to different duty cycle values;

[0053] S3: The switch signal carrying duty cycle information is transmitted from the indoor unit to the outdoor unit;

[0054] S4: Receive and measure the duty cycle of the switch signal within a preset communication cycle in the outdoor unit, and decode the corresponding quantized control command based on the measured duty cycle value;

[0055] S5: The outdoor unit adjusts the operating frequency of the inverter compressor based on the decoded quantized control commands.

[0056] The above solution has significant technical advantages:

[0057] (1) Significantly reduce system costs and improve versatility and adaptability:

[0058] Because this application uses "switching signals" as the information carrier, its physical layer can be constructed from extremely simple and inexpensive relays and ordinary wires, completely avoiding the need for dedicated communication transceiver chips (such as RS-485 / CAN transceivers), dedicated shielded cables, and complex communication protocol software stacks. This directly leads to a significant reduction in the hardware cost of the indoor and outdoor unit control boards. At the same time, this communication method based on a simple electrical interface has extremely high versatility, making it easy to achieve compatibility between indoor and outdoor units of different brands and models, or to carry out energy-saving retrofits on existing fixed-frequency / simple variable-frequency air conditioners, thereby greatly expanding the product's market adaptability and deployment flexibility.

[0059] (2) Achieve refined frequency conversion control and significantly improve energy efficiency:

[0060] By quantizing control commands and encoding them using duty cycles, this application achieves multi-level step-by-step adjustment of the compressor frequency (e.g., ±2 / ±4 / ±6Hz, etc.). Compared to the traditional on / off or high / low two-level modes of switch control, this refined adjustment capability allows the compressor's cooling / heating output to more accurately match the room's real-time dynamic heat load. This avoids frequent start-stop or prolonged high-frequency operation due to overshoot, ensuring that the compressor operates in its most efficient operating range most of the time. This significantly improves the overall energy efficiency ratio (EER / COP) of the air conditioning system, ultimately achieving the goal of energy saving and emission reduction.

[0061] (3) Improve temperature control accuracy and optimize user comfort experience:

[0062] The refined energy output regulation directly results in more stable indoor temperature control. Because the system can make small, gradual frequency adjustments, it avoids the drastic fluctuations in indoor temperature caused by large changes in energy output in traditional control methods. This application can maintain the room temperature more stably near the user-set value, providing a constant and uniform comfortable environment, thereby greatly improving the user's actual experience.

[0063] (4) Enhanced system reliability and robustness:

[0064] The hardware architecture (relays, simple circuits) upon which this application relies has been rigorously tested and is technologically mature. It is inherently more robust than complex digital communication systems and less susceptible to electromagnetic interference or protocol-layer software errors. The duty cycle decoding method, based on time measurement, is also insensitive to slight fluctuations in signal voltage. Therefore, the entire control system possesses higher inherent reliability and environmental adaptability (robustness), reducing failure rates and maintenance costs.

[0065] Preferably, in step S1, the state parameters include indoor ambient temperature and set temperature, and the calculation and generation of quantified control commands includes:

[0066] The temperature deviation is calculated based on the difference between the indoor ambient temperature and the set temperature.

[0067] Energy requirement parameters are calculated based on temperature deviation;

[0068] The control command is determined based on the energy demand parameter.

[0069] In the above scheme, key information reflecting the actual indoor thermal state and the user's desired thermal state in real time is the foundation for achieving closed-loop temperature control. Quantifying the difference between the current indoor environment and the set value accurately reflects the temperature error that the system needs to eliminate, providing the core driving signal for subsequent control algorithms. Through specific calculations, the simple temperature deviation is transformed into a more comprehensive and dynamic energy demand parameter. This allows control decisions to not only rely on instantaneous temperature differences but also consider changing trends and historical accumulation, thus providing a smoother and more accurate basis for subsequent compressor adjustments. Mapping the calculated energy demand parameter to a finite number of discrete frequency adjustment commands is a necessary quantification step because it simplifies complex control requirements into several definite states that can be transmitted through a carrier with limited information capacity (such as duty cycle signals). At the same time, these quantized commands represent different levels of adjustment requirements, forming the basis for multi-level variable frequency control, which has a higher precision than simple ON / OFF or high / low two-level control.

[0070] Preferably, the energy requirement parameters calculated based on temperature deviation include:

[0071] Q1=Q2+4*(△t1-△t2)+r*(△t1+△t2)*40 / f

[0072] Where Q1 represents the energy demand parameter of the current cycle; Δt1 represents the temperature deviation of the current cycle; Δt2 represents the temperature deviation of the previous cycle; Q2 represents the energy demand parameter of the previous cycle; r is the integral coefficient; and f is the value function.

[0073] In the above scheme, the introduction of the previous cycle state (Q2, Δt2) makes the current energy demand calculation not only based on instantaneous temperature deviation, but also possesses memory and accumulation effects. The accumulation effect of Q2 helps to eliminate the final steady-state temperature error, ensuring that the temperature can be accurately locked near the set value. The introduction of Δt2 allows the algorithm to sense the trend of temperature change, achieving earlier response and smoother control. The term based on the deviation change rate (Δt1-Δt2) enables the system to react promptly to rapid temperature changes. When the temperature deviates from the set value faster, this term rapidly increases Q1, prompting the compressor to increase output more quickly; when the temperature approaches the set value too quickly, this term rapidly decreases Q1 to avoid overshoot. This helps improve the dynamic response performance and control stability of the system. The term based on the deviation value (Δt1+Δt2) and adjusted by r and f: This term (when r=1) provides control force related to the deviation amplitude, ensuring that the larger the deviation, the larger the change amplitude of the calculated energy demand parameter, thereby driving a larger frequency adjustment to eliminate the deviation as quickly as possible. Meanwhile, the dynamic adjustment of r and f can make the contribution of this term change as the temperature deviates from the set value, thus achieving a more intelligent control strategy.

[0074] Preferably, the integral coefficient r and the value function f are determined based on the absolute value of the current period temperature deviation Δt1, specifically as follows:

[0075] When |△t1|≥10, f=5, r=1;

[0076] When 0.5 ≤ |△t1| < 10, f = 60 - (|△t1| - 1) × 55 / 9, r = 1;

[0077] When |△t1|<0.5, r=0.

[0078] In the above scheme, when |Δt1| is large, f takes a small value and r = 1, which enhances the control action related to the deviation and causes a larger change in the energy demand parameter Q1. This drives the compressor to increase or decrease the frequency more quickly (depending on the direction of the temperature difference), accelerating the indoor temperature towards the set value. When |Δt1| is moderate, f increases as the deviation decreases, causing the control action to gradually weaken. This avoids overshoot caused by excessive control force when approaching the set value, making temperature changes smoother and improving user comfort. When |Δt1| is very small, r = 0, eliminating the control term directly related to the deviation amplitude. At this time, the algorithm mainly maintains the existing state and responds to small trend changes, reducing unnecessary control actions and frequency fluctuations. This helps the system operate at a lower and more stable frequency after reaching the set temperature, maximizing energy saving while maintaining comfort and avoiding integral saturation.

[0079] Preferably, the quantized control command is a compressor frequency increment, determined according to the numerical range of the energy demand parameter Q1, including +6Hz, +4Hz, +2Hz, 0Hz, -2Hz, -4Hz and -6Hz.

[0080] In the above scheme, the complex energy demand calculation result (Q1) is transformed into a finite, discrete frequency adjustment command. This allows the control information to adapt to communication media with limited information capacity (such as duty cycle signals), resolving the contradiction between complex information and simple signals. It provides seven different frequency increment / decrease levels, enabling the compressor speed to be adjusted according to the level of energy demand, achieving smoother and more precise energy output regulation than traditional fixed-speed or simple two-level control. For example, ±2Hz is used when only fine-tuning is needed; ±6Hz is used when large adjustments are required. The complex energy demand parameters are transformed into intuitive frequency adjustment commands (+ / -Hz), facilitating subsequent encoding and decoding. The frequency converter typically operates by receiving frequency increase / decrease commands or target frequency commands.

[0081] Preferably, in step S2, the correspondence between encoding the control command into duty cycles is as follows:

[0082] A compressor frequency increase of -6Hz corresponds to a duty cycle of 20%.

[0083] A compressor frequency increase of -4Hz corresponds to a duty cycle of 30%.

[0084] A compressor frequency increase of -2Hz corresponds to a duty cycle of 40%.

[0085] A 0Hz increase in compressor frequency corresponds to a 50% duty cycle;

[0086] A compressor frequency increase of +2Hz corresponds to a duty cycle of 60%.

[0087] A compressor frequency increase of +4Hz corresponds to a duty cycle of 70%.

[0088] A compressor frequency increase of +6Hz corresponds to a duty cycle of 80%.

[0089] In the above scheme, by encoding information into the duty cycle, the simple switch signal, which could only transmit two states (ON / OFF), can now transmit seven different control commands (corresponding to seven duty cycles), significantly improving the dimension of information transmission. It successfully maps the multi-level frequency increment commands generated by the indoor unit onto a transmittable signal form, providing the necessary information carrier for the outdoor unit to decode and realize multi-level frequency conversion adjustment. It creatively utilizes the cumulative characteristics of the switch signal over time (duty cycle), rather than relying solely on its instantaneous level, which is a method of integrating digital information into analog time waveforms.

[0090] Preferably, in step S3, the switching signal is a 24V AC voltage signal, which is controlled by the on / off state of a relay, and the switching signal is transmitted between the indoor unit and the outdoor unit through a single signal line.

[0091] The above solution, using relays and a standard 24V power supply, is one of the most basic and cost-effective hardware solutions in the HVAC control field. It avoids dedicated digital communication chips, complex transceiver circuits, and advanced MCUs, significantly reducing the hardware cost of the indoor and outdoor unit control boards. 24VAC control signals are widely used in the HVAC field, and many outdoor units themselves have 24V control inputs (although usually only used for start / stop). This application is compatible with this basic interface, allowing its control solution to be more widely applied to outdoor units of different brands or models, especially suitable for energy-saving retrofits of existing fixed-speed air conditioners. If the outdoor unit has inverter capability but the control interface is simple, it can be paired with a specially designed inverter outdoor unit. Single-wire connection also simplifies compatibility issues with existing wiring.

[0092] Preferably, in step S4, before transmitting the switch signal carrying duty cycle information, the indoor unit sends a synchronization signal to the outdoor unit. The synchronization signal is a continuous switch signal with a preset duration, used to align the time axes of the indoor unit and the outdoor unit.

[0093] The synchronization signal is a continuous ON signal lasting 30 seconds. After the synchronization signal ends, the indoor unit and the outdoor unit simultaneously start a 60-second communication cycle timer.

[0094] After one communication cycle ends, the system enters a 120-second waiting period before starting the next control and adjustment cycle.

[0095] In the above scheme, the 30-second continuous ON synchronization signal provides a clear and stable time reference point, ensuring that the indoor and outdoor units can start duty cycle timing measurement at almost the same moment, avoiding duty cycle measurement errors caused by different start times. The fixed and synchronized 60-second communication cycle provides a precise time window for the outdoor unit to measure the ON duration of the signal, which is the basis for decoding the correct instruction from the duty cycle. The 120-second waiting period sets the update frequency of control instructions, avoiding the impact of frequent adjustments on system stability. This allows the system time to reach a new steady state after each adjustment, and the indoor unit can also recalculate energy demand during this period, improving the effectiveness and stability of control. Based on the fixed duration and simple ON / OFF state changes as synchronization events, the entire communication protocol is very simple and easy to implement in a low-cost MCU, without the need for a complex communication protocol stack.

[0096] Preferably, the method for calculating the temperature deviation is related to the air conditioning operating mode:

[0097] In cooling mode, the temperature deviation Δt1 = T1 - Ts;

[0098] In heating mode, the temperature deviation Δt1 = Ts - T1;

[0099] Where T1 is the indoor ambient temperature and Ts is the set temperature.

[0100] In the above scheme, by standardizing the meaning of Δt1, the subsequent algorithms for calculating energy demand parameters and determining frequency increments based on Δt1 do not need to distinguish between cooling and heating modes. They can use the same set of logic and parameter tables, which reduces the complexity of algorithm design. In any mode, a positive Δt1 clearly indicates that more energy output is needed to correct the temperature, while a negative Δt1 indicates that energy input needs to be reduced or energy needs to be removed.

[0101] Preferably, in step S5, adjusting the operating frequency of the variable frequency compressor includes:

[0102] Adjusted frequency = current operating frequency + frequency increment;

[0103] Calculate the new operating frequency and control the variable frequency compressor to operate at the new operating frequency.

[0104] In the above scheme, the outdoor unit can receive and apply frequency increments (±2Hz, ±4Hz, ±6Hz) from the indoor unit at different speeds, thereby achieving multi-level step-by-step adjustment of the compressor speed. This allows the compressor output capacity to more precisely match actual needs, superior to traditional fixed-speed or simple two-speed inverters. Combined with the energy demand parameters accurately calculated by the indoor unit and quantified commands, the frequency adjustment performed by the outdoor unit can more accurately reflect the current energy demand. For example, when energy demand is high, the frequency increases significantly (+6Hz); when energy demand is low and stable, the frequency remains unchanged (0Hz) or is slightly adjusted (±2Hz). Because the frequency is adjusted gradually (at different speeds) rather than abruptly or simply by starting and stopping, the compressor's operating status changes more smoothly, reducing the impact on the power grid, lowering noise, and helping to maintain a more stable indoor temperature, thus improving user comfort. Based on existing inverter compressors and inverter drives, the incremental method of control commands is compatible with common inverter control modes.

[0105] In one embodiment provided in this application, 24VAC communication is used to control the adjustment of indoor and outdoor functions through the duty cycle of relay switching. The specific control logic is as follows:

[0106] The indoor and outdoor units are connected by an N1 signal line. The indoor unit calculates the energy requirement based on the difference between the indoor set temperature and the return air temperature, and transmits the energy requirement value to the outdoor unit through the N1 signal. The outdoor unit then controls the compressor speed.

[0107] The formula for calculating internal working capacity is as follows:

[0108] Energy requirements are calculated as follows:

[0109] Q1=Q2+4*(△t1-△t2)+r*(△t1+△t2)*40 / f

[0110] During cooling, Δt1 = T1 - Ts; during heating, Δt1 = Ts - T1; Δt1 is the deviation for the current cycle; Δt2 is the deviation for the previous cycle; Q1 is the energy demand increment for the current cycle; Q2 is the energy demand increment for the previous cycle; r is the integral coefficient; f is the value function.

[0111] Data should be retrieved according to Table 1 below.

[0112] Abs(△t1) f r ≥10 5 1 0.5≤Abs(△t1)<10 60-(Abs(△t1)-1)×55 / 9 1 ＜0.5 - 0

[0113] Table 1 Value Range

[0114] The temperature sensed by the sensor is substituted into the energy demand formula to calculate the energy demand. The calculation results are taken from Table 2 below. Compressor speed = initial speed + frequency increment:

[0115] Q1 decline phase Frequency increment determination Q1 Upward Phase Frequency increment determination Q1＞21 6 Q1＜12 0 (Maintain) 20＜Q1≤21 4 Q1＜20 2 19≤Q1≤20 2 Q1＜30 4 10＜Q1＜19 0 (Maintain) Q1≥30 6 Q1＜10 -2 Q1＜8 -4 Q1＜6 -6

[0116] Table 2 Compressor Frequency Increase Table

[0117] The compressor operates according to the startup platform. Six minutes after the platform operation is complete, the compressor speed is adjusted based on the above formula. The speed signal is transmitted in the following manner.

[0118] When the indoor unit needs to send a frequency increase / decrease request to the outdoor unit, it first sends a time synchronization signal to the outdoor unit to ensure that it corresponds with the outdoor unit's time axis: the N1 output ON signal is turned off after 30 seconds, and the indoor and outdoor units start a 60-second frequency increase / decrease judgment cycle timer at the same time. Based on the duty cycle time, the compressor speed change is input to the outdoor unit. After each adjustment, it takes another 120 seconds to enter the next adjustment.

[0119] N1 signal duty cycle 20%: compressor -6Hz;

[0120] N1 signal duty cycle 30%: compressor -4Hz;

[0121] N1 signal duty cycle 40%: compressor -2Hz;

[0122] N1 signal duty cycle 50%: compressor speed remains constant;

[0123] N1 signal duty cycle 60%: compressor +2Hz;

[0124] N1 signal duty cycle 70%: compressor +4Hz;

[0125] N1 signal duty cycle 80%: compressor +6Hz;

[0126] The energy demand parameters are calculated by setting the temperature of the indoor unit. The energy demand parameters are then used to find a reasonable compressor speed control by looking up a table. This control is then sent to the outdoor unit via duty cycle, thus enabling the outdoor unit to control the compressor speed.

[0127] Taking the initial startup as an example, the calculation is explained as follows:

[0128] For the initial startup, assuming the indoor air temperature is 29℃ and the set temperature is 25℃, Δt1 = 4, then the values ​​of r and f are calculated by referring to the table. Q2 is initially equal to 0, and then equal to the previous Q1. Δt1 is initially equal to 0, and then equal to the previous Δt1. Substituting the obtained values ​​into the formula, the calculation results are shown in the table. At the same time, the calculation process of the room temperature decreasing from 29℃ to 22℃ and then increasing from 22℃ to 29℃ was simulated. According to the calculation results, the compressor speed increment is shown in the table.

[0129]

[0130]

[0131] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for controlling the function of an air conditioner, applied to an air conditioning system including an indoor unit and an outdoor unit, characterized in that, include: S1: Obtain at least one state parameter characterizing the operating requirements of the air conditioning system in the indoor unit, and calculate and generate a quantitative control command based on the state parameter to adjust the operating frequency of the variable frequency compressor in the outdoor unit. S2: The indoor unit encodes the control command into the duty cycle of a switch signal within a preset communication cycle, where different values ​​of the quantized control command correspond to different duty cycle values; S3: The switch signal carrying duty cycle information is transmitted from the indoor unit to the outdoor unit; S4: Receive and measure the duty cycle of the switch signal within a preset communication cycle in the outdoor unit, and decode the corresponding quantized control command based on the measured duty cycle value; S5: The outdoor unit adjusts the operating frequency of the inverter compressor based on the decoded quantized control commands.

2. The air conditioning function requirement control method according to claim 1, characterized in that, In step S1, the state parameters include the indoor ambient temperature and the set temperature, and the calculation and generation of quantized control commands includes: The temperature deviation is calculated based on the difference between the indoor ambient temperature and the set temperature. Energy requirement parameters are calculated based on temperature deviation; The control command is determined based on the energy demand parameter.

3. The air conditioning function requirement control method according to claim 2, characterized in that, The energy requirement parameters calculated based on temperature deviation include: Q1=Q2+4*(△t1-△t2)+r*(△t1+△t2)*40 / f Where Q1 represents the energy demand parameter of the current cycle; Δt1 represents the temperature deviation of the current cycle; Δt2 represents the temperature deviation of the previous cycle; Q2 represents the energy demand parameter of the previous cycle; r is the integral coefficient; and f is the value function.

4. The air conditioning function requirement control method according to claim 3, characterized in that, The integral coefficient r and the value function f are determined based on the absolute value of the current period temperature deviation Δt1, specifically as follows: When |△t1|≥10, f=5, r=1; When 0.5 ≤ |△t1| < 10, f = 60 - (|△t1| - 1) × 55 / 9, r = 1; When |△t1|<0.5, r=0.

5. The air conditioning function requirement control method according to claim 3, characterized in that, The quantized control command is a compressor frequency increment, determined according to the value range of the energy requirement parameter Q1, including +6Hz, +4Hz, +2Hz, 0Hz, -2Hz, -4Hz, and -6Hz.

6. The air conditioning function requirement control method according to claim 3, characterized in that, In step S2, the correspondence between encoding the control command into duty cycles is as follows: A compressor frequency increase of -6Hz corresponds to a duty cycle of 20%. A compressor frequency increase of -4Hz corresponds to a duty cycle of 30%. A compressor frequency increase of -2Hz corresponds to a duty cycle of 40%. A 0Hz increase in compressor frequency corresponds to a 50% duty cycle; A compressor frequency increase of +2Hz corresponds to a duty cycle of 60%. A compressor frequency increase of +4Hz corresponds to a duty cycle of 70%. A compressor frequency increase of +6Hz corresponds to a duty cycle of 80%.

7. The air conditioning function requirement control method according to claim 6, characterized in that, In step S3, the switch signal is a 24V AC voltage signal, which is controlled by the on / off state of a relay. The switch signal is transmitted between the indoor unit and the outdoor unit through a single signal line.

8. The air conditioning function requirement control method according to claim 7, characterized in that, In step S4, before transmitting the switch signal carrying duty cycle information, the indoor unit sends a synchronization signal to the outdoor unit. The synchronization signal is a continuous switch signal with a preset duration, used to align the time axes of the indoor unit and the outdoor unit. The synchronization signal is a continuous ON signal lasting 30 seconds. After the synchronization signal ends, the indoor unit and the outdoor unit simultaneously start a 60-second communication cycle timer. After one communication cycle ends, the system enters a 120-second waiting period before starting the next control and adjustment cycle.

9. The air conditioning function requirement control method according to claim 3, characterized in that, The calculation method for the temperature deviation is related to the air conditioning operating mode: In cooling mode, the temperature deviation Δt1 = T1 - Ts; In heating mode, the temperature deviation Δt1 = Ts - T1; Where T1 is the indoor ambient temperature and Ts is the set temperature.

10. The air conditioning function requirement control method according to claim 8, characterized in that, In step S5, adjusting the operating frequency of the variable frequency compressor includes: Adjusted frequency = current operating frequency + frequency increment; Calculate the new operating frequency and control the variable frequency compressor to operate at the new operating frequency.

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