Control method for air conditioner and air conditioner

Abstract

The application relates to a control method for an air conditioner and the air conditioner, wherein the control method comprises the following steps: acquiring an input voltage of an alternating-current power input in the air conditioner and an instantaneous power of the alternating-current power input; determining a first current component to be injected according to the instantaneous power of the alternating-current power input and / or the input voltage of the alternating-current power input; generating a first current by using a control module, injecting the first current component on the first current, and obtaining an injected current; determining a motor driving signal of the air conditioner according to the injected current; and driving the compressor to operate according to the motor driving signal. By injecting a current based on a power waveform and / or a voltage waveform in the air conditioner, the application can improve the power factor of the power supply in the air conditioner, reduce the charging and discharging current of the bus capacitor, and prolong the service life of the bus capacitor.

Description

Technical Field

[0001] This application relates to the field of air conditioner technology, and in particular to a control method for an air conditioner and an air conditioner. Background Technology

[0002] In related technologies, air conditioners are generally divided into indoor and outdoor units. The outdoor unit of an air conditioner contains a control circuit and loads such as a compressor, fan, and relays. The control circuit of the outdoor unit receives alternating current, such as from the mains, to drive the load. The load requires a stable input power, but in reality, the input power at the load end fluctuates, necessitating the use of a bus capacitor to balance these fluctuations.

[0003] However, the bus capacitors are frequently charged and discharged, leading to heat generation and accelerating the aging process. Related technologies often employ injecting high-order harmonic signals into the input AC current to reduce the peak value of the bus current, thereby reducing the heat generated by the bus capacitors. However, this results in a decrease in the circuit's power factor. Summary of the Invention

[0004] In view of this, this application proposes a control method and an air conditioner for an air conditioner, which can improve the power factor of the power supply in the air conditioner while reducing the charging and discharging current of the bus capacitor, thereby improving the life of the bus capacitor.

[0005] According to one aspect of this application, a control method for an air conditioner is provided, the air conditioner including an AC power supply, a control module, and a compressor, the method comprising: acquiring the input voltage and instantaneous power of the AC power supply currently input to the air conditioner; determining a first current component to be injected based on the instantaneous power and / or the input voltage of the AC power supply; generating a first current using the control module, and injecting the first current component into the first current to obtain an injected current; determining a motor drive signal for the air conditioner based on the injected current; and driving the compressor to operate based on the motor drive signal.

[0006] Further, determining the first current component to be injected based on the instantaneous power of the AC power input includes: acquiring the input current of the AC power input in the current air conditioner; determining the instantaneous power of the AC power input based on the input voltage and the input current of the AC power input; determining a first current coefficient based on the instantaneous power of the AC power input; and determining the first current component to be injected based on the first current coefficient.

[0007] Further, determining the first current component to be injected based on the first current coefficient includes: generating a second current using the control module; adjusting the amplitude or phase of the second current to obtain a third current; and determining the first current component to be injected based on the first current coefficient and the third current.

[0008] Further, determining the first current coefficient based on the instantaneous power input of the AC power source includes: acquiring the frequency of the AC power source, detecting the peak value of the instantaneous power based on the frequency of the AC power source, and obtaining a peak power with the same frequency as the AC power source; and determining the first current coefficient based on the peak power and the instantaneous power.

[0009] Further, adjusting the amplitude or phase of the second current to obtain the third current includes: adjusting the amplitude of the second current according to the frequency of the AC power supply to obtain the effective value of the second current; obtaining the third current based on the effective value of the second current, or detecting the real-time value of the input voltage; determining a first phase offset based on the real-time value of the input voltage, wherein the first phase offset is the angle of rotation of the compressor when the real-time value of the input voltage is zero; and adjusting the phase of the second current based on the first phase offset to obtain the third current.

[0010] Further, determining the first current component to be injected based on the input voltage of the AC power supply includes: determining a second current coefficient based on the input voltage of the AC power supply; and determining the first current component to be injected based on the second current coefficient.

[0011] Further, determining the first current component to be injected based on the second current coefficient includes: generating a fourth current using the control module; adjusting the amplitude or phase of the fourth current to obtain a fifth current; and determining the first current component based on the second current coefficient and the fifth current.

[0012] Further, determining the second current coefficient based on the input voltage of the AC power supply includes: acquiring the frequency of the AC power supply, detecting the peak value of the input voltage based on the frequency of the AC power supply, and obtaining a peak voltage with the same frequency as the AC power supply; and determining the second current coefficient based on the peak voltage and the input voltage.

[0013] Further, adjusting the amplitude or phase of the fourth current to obtain the fifth current includes: adjusting the amplitude of the fourth current according to the frequency of the AC power supply to obtain the effective value of the fourth current; obtaining the fifth current based on the effective value of the fourth current, or detecting the real-time value of the input voltage; pre-setting a second phase offset using the control module; and adjusting the phase of the fourth current according to the real-time value of the input voltage and the second phase offset to obtain the fifth current.

[0014] According to another aspect of this application, an air conditioner is provided, the air conditioner comprising: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute the control method for the air conditioner.

[0015] By first acquiring the input voltage and instantaneous power of the AC power input in the current air conditioner, then determining the first current component to be injected based on the instantaneous power and / or the input voltage of the AC power input, then generating a first current using the control module, and injecting the first current component into the first current to obtain the injected current, and finally determining the motor drive signal of the air conditioner based on the injected current and driving the compressor to operate based on the electrode drive signal, according to various aspects of this application, current based on power waveform and / or voltage waveform can be injected into the air conditioner, thereby improving the power factor of the power supply in the air conditioner while reducing the charging and discharging current of the bus capacitor, thereby improving the life of the bus capacitor. Attached Figure Description

[0016] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0017] Figure 1 A flowchart illustrating a control method for an air conditioner according to an embodiment of this application is shown.

[0018] Figure 2 A schematic diagram of the structure of an air conditioner according to an embodiment of this application is shown.

[0019] Figure 3 A schematic diagram of the control module according to an embodiment of this application is shown.

[0020] Figure 4 A schematic diagram of a power waveform injection module according to an embodiment of this application is shown.

[0021] Figure 5 A schematic diagram of a power waveform injection module according to an embodiment of this application is shown.

[0022] Figure 6 A schematic diagram of the control module according to an embodiment of this application is shown.

[0023] Figure 7 A schematic diagram of a voltage waveform injection module according to an embodiment of this application is shown.

[0024] Figure 8 A schematic diagram of a voltage waveform injection module according to an embodiment of this application is shown.

[0025] Figure 9 A schematic diagram of the control module according to an embodiment of this application is shown. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0027] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] The following disclosure provides many different implementations or examples for carrying out different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials. In some instances, methods, means, elements, and circuits well known to those skilled in the art are not described in detail in order to highlight the main points of this application.

[0030] Figure 1 A flowchart illustrating a control method for an air conditioner according to an embodiment of this application is shown.

[0031] like Figure 1 As shown, the air conditioner includes an AC power supply, a control module, and a compressor. The control method for the air conditioner includes:

[0032] Step S10: Obtain the input voltage and instantaneous power of the AC power input in the current air conditioner;

[0033] Step S20: Determine the first current component to be injected based on the instantaneous power of the AC power input and / or the input voltage of the AC power input;

[0034] Step S30: Use the control module to generate a first current, and inject the first current component into the first current to obtain the injected current;

[0035] Step S40: Determine the motor drive signal of the air conditioner based on the injected current;

[0036] Step S50: Drive the compressor to operate according to the electrode drive signal.

[0037] By first acquiring the input voltage and instantaneous power of the AC power input in the current air conditioner, then determining the first current component to be injected based on the instantaneous power and / or the input voltage of the AC power input, then generating a first current using the control module, and injecting the first current component into the first current to obtain the injected current, and finally determining the motor drive signal of the air conditioner based on the injected current and driving the compressor to operate based on the electrode drive signal, this application can inject current based on power waveform and / or voltage waveform into the air conditioner, thereby improving the power factor of the power supply in the air conditioner while reducing the charging and discharging current of the bus capacitor, thereby improving the life of the bus capacitor.

[0038] It should be noted that the air conditioner may include an indoor unit and an outdoor unit. Optionally, the control method for the air conditioner is applied to the outdoor unit of the air conditioner. Of course, the indoor and outdoor units of the air conditioner can also be integrated, such as in a window air conditioner, and the control method for the air conditioner is equally applicable. Furthermore, the air conditioner can be an inverter air conditioner or a fixed-frequency air conditioner. For ease of explanation, the following description uses the application of the control method for the air conditioner to the outdoor unit as an example. It is understood that this application does not limit the type of air conditioner.

[0039] Figure 2 A schematic diagram of the structure of an air conditioner according to an embodiment of this application is shown.

[0040] like Figure 2 As shown, the air conditioner can be an inverter air conditioner. The outdoor unit of the air conditioner may include an AC power supply, a power factor correction module, an intelligent power module, and a compressor, etc. It can be understood that... Figure 2 The structure in the document can be the hardware portion of the outdoor unit of the air conditioner. The outdoor unit may also include, for example, a software portion consisting of algorithms, which can be used to control the operation of the hardware portion of the outdoor unit. For example, the control module may also include a processor ( Figure 2 (not shown in the image) and a program running on the processor, which can load a pre-set program to send control signals to the power factor correction module.

[0041] See Figure 2 The AC power supply may include mains power (AC), a rectifier bridge, and a filter inductor L1. The mains power may be 220V AC voltage with a frequency of 50Hz or 60Hz. After bridge rectification, this AC voltage outputs a fluctuating AC voltage V in a "bun" shape. db (That is, the input voltage of the AC power supply). For example, AC voltage V db It can include only the positive half-cycle of a sine wave. The filter inductor L1 can filter out large fluctuations in the AC voltage V. db Smoothing filtering is performed to obtain a DC voltage with smaller fluctuations.

[0042] Furthermore, the output of the rectifier bridge includes positive and negative terminals. AC voltage V db The sampling points can collect the voltage and AC current I between the positive and negative terminals of the rectifier bridge output. ac The sampling point for the AC power input (i.e., the input current) can be located at the negative terminal of the rectifier bridge output. It can be understood that the AC current I... ac The sampling point can also be located at the positive terminal of the rectifier bridge output. This application applies to AC voltage V. db Sampling points and AC current Iac The location of the sampling points is not limited.

[0043] Further, the input voltage and input current of the AC power supply are obtained, and the instantaneous power of the AC power supply is calculated based on the input voltage and input current. For example, in Figure 2 In the middle, the collected AC voltage V db and alternating current I ac Perform a product operation to obtain the instantaneous power P. ac That is, P ac =V db *I ac .

[0044] although Figure 2 As not shown in the diagram, those skilled in the art should understand that the outdoor unit of the air conditioner may also include a processor, a communication module, a solenoid four-way valve, and a condenser, which, together with the indoor unit, form the complete air conditioner unit for cooling or heating. For example, the communication module of the outdoor unit can send detection signals, fault diagnosis information, and operating status signals from the outdoor unit to the indoor unit for processing. The indoor unit can send control signals to the outdoor unit via the communication module to control the operation of the solenoid four-way valve, etc. It is understood that this application does not limit the specific structure and composition of the outdoor unit of the air conditioner.

[0045] Further, see Figure 2 The power factor correction (PFC) module may include transistor Q1, diode D1, and bus capacitor C1. Transistor Q1 can be a bipolar transistor or a field-effect transistor. The gate of transistor Q1 can receive a first control signal output from the outdoor unit's processor. This first control signal can be a pulse width modulation (PWM) signal, used to control the transistor Q1 to turn on or off. Bus capacitor C1 is used to balance the bus voltage V. bus Fluctuations. Diode D1 can prevent the influence of downstream circuits, such as those of intelligent function modules, on the PFC module, thus providing protection. The power factor correction module can be of the Boost type. It is understood that this application does not limit the type of power factor correction module or the types of components in the power factor correction module.

[0046] Furthermore, in Figure 2In this context, the Intelligent Power Module (IPM) can be a hybrid integrated circuit, including inverter circuits, logic control circuits, detection circuits, and power interfaces. For example, the detection circuit can be used for undervoltage detection. It is worth noting that the outdoor unit of a variable frequency air conditioner may include a variable frequency module, which may include the intelligent power module. The variable frequency module can be used to adjust the compressor speed to achieve changes in the air conditioner's cooling or heating capacity. In addition to the intelligent power module, the variable frequency module may also include optocouplers, connectors, and peripheral components.

[0047] For example, the optocoupler can receive a second control signal sent by the processor of the outdoor unit, perform photoelectric conversion on the received second control signal to obtain a third control signal, and then send the photoelectric converted third control signal to the intelligent power module. At the same time, the optocoupler also plays an isolation role.

[0048] Furthermore, the logic control circuit can perform logic processing on the third control signal to generate a fourth control signal for driving the inverter circuit, and the fourth control signal can be a pulse width modulation signal.

[0049] Furthermore, the inverter circuit may include six insulated gate bipolar transistors (IGBTs) and six damped diodes. The IGBTs are also called gate-controlled transistors; it is understood that the IGBTs can also be replaced by power transistors or field-effect power transistors. This application does not limit the type of transistors in the inverter circuit.

[0050] See also Figure 2 The input to the intelligent power module can be the bus voltage V. bus The voltage between the positive and negative power lines of the intelligent power module input is used to provide power to the intelligent power module. The output of the intelligent module can be a three-phase drive signal, including U-phase current, W-phase current, and V-phase current, used to drive the compressor. Three sampling points can be set at the output of the intelligent power module to collect the U-phase current, W-phase current, and V-phase current, respectively.

[0051] Furthermore, the fourth control signal generated by the logic control circuit can be sent to the gate of each IGBT in the inverter circuit to control the conduction and cutoff of each IGBT. In addition, by controlling the conduction sequence of each IGBT, the direction and sequence of the current in each winding of the compressor can be controlled, thereby forming a rotating magnetic field that rotates the rotor in the compressor, driving the compressor to work. In one example, the inverter circuit can invert and convert the DC voltage (e.g., bus voltage) sent to the intelligent power module into an AC frequency conversion signal (e.g., a three-phase drive signal) to control the compressor.

[0052] Furthermore, the compressor can employ a brushless DC motor, i.e., a DC inverter motor. This brushless DC motor is three-phase and has high control precision. Alternatively, the compressor can also employ an AC induction motor, i.e., an AC inverter motor. It is understood that this application does not limit the type of compressor.

[0053] Furthermore, the compressor employs a brushless DC motor, the stator of which may be wound with electromagnetic coils, and the rotor uses permanent magnets. The voltage or current signal applied to the brushless DC motor can be a pulse signal output by the intelligent power module. When the amplitude or frequency of the voltage or current signal applied to the brushless DC motor increases, the speed increases; when the amplitude or frequency of the voltage or current signal applied to the brushless DC motor decreases, the speed decreases.

[0054] Furthermore, the compressor employs an AC induction motor. The voltage or current signal applied to this brushless DC motor can be a three-phase sinusoidal signal output from the intelligent power module, with each phase differing by 120 degrees. In this case, the inverter circuit in the intelligent power module can inversely convert the input DC voltage into an AC signal, and the inverse conversion process can be controlled by instructions sent by the processor of the outdoor unit.

[0055] The structure and operation of the main hardware components of the air conditioner have been described above. It can be understood that the outdoor unit of the air conditioner also includes a processor, and the control method for the air conditioner can run on the processor of the outdoor unit. Preferably, the processor of the outdoor unit can be a DSP processor.

[0056] Figure 3 A schematic diagram of the control module according to an embodiment of this application is shown.

[0057] like Figure 3As shown, the control module may include multiple functional modules, such as a speed loop regulator, a position observer, and a current loop regulator. The control module can adjust based on the acquired three-phase drive signals and output six PWM signals to the intelligent power module to regulate the rotational speed and angle of the motor inside the compressor. It is understood that each functional module of the control module can be implemented using software, programs, or algorithms. Notably, the power waveform injection module can be located between the speed loop regulator and the field weakening and MTPA control modules; that is, in specific program or algorithm steps, the power waveform injection module can be executed after the speed loop regulator and before the field weakening and MTPA control modules.

[0058] See Figure 3 The three-phase drive signal output by the intelligent power module can be sampled to obtain the U-phase current I in the compressor's three-phase coordinate system. u Phase W current I w and V-phase current I v Then, combining the rotation angle of the rotor inside the compressor, the current in the three-phase coordinate system is transformed into the d-axis current I in the two-phase coordinate system through Park and Clark transformations. d and q-axis current I q .

[0059] Furthermore, in Figure 3 In the middle, the position observer can obtain the bus voltage V bus d-axis voltage U d q-axis voltage U q d-axis current I d q-axis current I q And can be based on the obtained bus voltage V bus d-axis voltage U d q-axis voltage U q d-axis current I d q-axis current I q The rotation angle (angle) and angular velocity (spd) of the rotor inside the compressor are calculated, where the angular velocity (spd) can be obtained by differentiating the angle (angle). It is understood that this application does not limit how the rotation angle and velocity of the rotor inside the compressor are obtained.

[0060] Further, see Figure 3The control module internally generates an angular velocity reference spdref and compares the angular velocity spd with the angular velocity reference spdref in a comparator. The comparison result between the angular velocity spd and the angular velocity reference spdref can be sent to the speed loop regulator for adjustment. It should be noted that the speed loop regulator can determine the first current (i.e., Is_in) based on the difference between the current rotor rotation angular velocity spd and the angular velocity reference spdref, meaning that the value of the first current at any given moment can change in real time.

[0061] Furthermore, in Figure 3 In this process, the power waveform injection module can inject the first current component into the first current to obtain the injected current Is_out.

[0062] Furthermore, the field weakening control and maximum torque-to-current ratio (MTPA) control module can be used to maintain the electromagnetic torque of the permanent magnet motor, ensuring its normal operation. The field weakening control and MTPA control module can receive the injected current, process it, and output an AC current. This AC current is then compared with the d-axis current I... d and q-axis current I q The samples are fed into different comparators, compared separately, and the results are then processed by different current loop regulators to obtain the d-axis voltage U. d and q-axis voltage U q d-axis voltage U d and q-axis voltage U q It can be used as input for a position observer.

[0063] Furthermore, the d-axis voltage U can be... d q-axis voltage U q The instantaneous values ​​of the three-phase voltages are obtained by performing Park and Clark inverse transforms on the angle. The control module may also include a pulse width modulator (PWM) for comparing the instantaneous values ​​of the three-phase voltages with carrier waves stored in the PWM to obtain six pulse width modulated (PWM) signals. The PWM may be a space vector pulse width modulator (SVPWM).

[0064] Further, determining the first current component to be injected based on the instantaneous power input of the AC power supply includes:

[0065] Step S21: Obtain the input current of the AC power supply in the current air conditioner;

[0066] Step S22: Determine the instantaneous power of the AC power input based on the input voltage and the input current of the AC power input;

[0067] Step S23: Determine the first current coefficient based on the instantaneous power input of the AC power supply;

[0068] Step S24: Determine the first current component to be injected based on the first current coefficient.

[0069] Further, determining the first current component to be injected based on the first current coefficient includes:

[0070] Step S25: Generate a second current using the control module;

[0071] Step S26: Adjust the amplitude or phase of the second current to obtain the third current;

[0072] Step S27: Determine the first current component to be injected based on the first current coefficient and the third current.

[0073] The first current component can be obtained by multiplying the first current coefficient and the third current. For example, if the first current coefficient is G and the third current is I1, then the first current component is G*I1.

[0074] Further, determining the first current coefficient based on the instantaneous power input of the AC power supply includes:

[0075] Step S231: Obtain the frequency of the AC power supply, and detect the peak value of the instantaneous power according to the frequency of the AC power supply to obtain the peak power with the same frequency as the AC power supply;

[0076] Step S232: Determine the first current coefficient based on the peak power and the instantaneous power.

[0077] The frequency of the AC power supply can be the frequency of mains power, such as 50Hz or 60Hz. By detecting the peak value of the instantaneous power based on the frequency or period of the AC power supply, the peak power P can be obtained. max In one example, the peak power P can be... max With instantaneous power P ac The ratio of these two values ​​is taken as the first current coefficient, i.e., the first current coefficient G = P. ac / P max .

[0078] For example, the input voltage can be expressed as: V = V max *cos(θ / f), where f can be the frequency of the AC power supply, and θ is the phase. That is, the frequency of the input voltage can be the same as and in phase with the AC mains power. Under the premise that the power factor is 1, the input current can be expressed as: I = I0 max*cos(θ / f), therefore, the instantaneous power can be expressed as:

[0079]

[0080] At this moment, P is the instantaneous power, and the peak power is V. ,ax *I max Therefore, the first current coefficient can be [1+cos(2θ / f)] / 2. Of course, 1+cos(2θ / f) can also be used as the first current coefficient. In addition, the first current coefficient can also be preset, and this application is not limited in this regard.

[0081] Further, adjusting the amplitude or phase of the second current to obtain the third current includes:

[0082] Step S261: Adjust the amplitude of the second current according to the frequency of the AC power supply to obtain the effective value of the second current;

[0083] Step S262: Obtain the third current based on the effective value of the second current.

[0084] or,

[0085] Step S263: Detect the real-time value of the input voltage;

[0086] Step S264: Determine the first phase offset based on the real-time value of the input voltage, wherein the first phase offset is the angle of rotation of the compressor when the real-time value of the input voltage is zero;

[0087] Step S265: Adjust the phase of the second current according to the first phase offset to obtain the third current.

[0088] It is worth noting that steps S261, S262 and steps S263, S264 and S265 can be different schemes for determining the third current, and can be equivalently replaced. In practical applications, they can be selected as needed.

[0089] Taking the adjustment of the amplitude of the second current to obtain the third current as an example, the effective value of the second current detected according to the frequency of the AC power supply can be used as the third current. The second current can be generated internally by the control module; specifically, it can be generated using software or hardware such as a sine wave generator. The waveform of the second current can be the same as or related to the waveform of the first current. The waveform of the second current can also be, for example, a triangular wave; this application does not limit the waveform of the second current.

[0090] Alternatively, the first current can be directly used as the second current. In this case, the waveform of the second current is the same as that of the first current, for example, both are sine waves. The second current can also be the output of the speed loop regulator.

[0091] Furthermore, taking the adjustment of the phase of the second current to obtain the third current as an example, the second current can be preset and can be associated with the first current coefficient. For example, the second current can be expressed as [1+cos(2θ / f)]. When the real-time value of the input voltage is detected to be zero, the rotation angle θ of the compressor at this time is recorded. zero and the angle θ zero The phase of the second current is adjusted as the first phase offset. For example, the second current can be adjusted to [1+cos(2(θ-θ)]. zero ) / f)).

[0092] Figure 4 A schematic diagram of a power waveform injection module according to an embodiment of this application is shown. Figure 4 As shown, Figure 4 One embodiment of the power waveform injection module.

[0093] First, the input voltage Vdb and input current Iac of the AC power supply are sampled, and the instantaneous power P is calculated using a multiplier. The instantaneous power P is then processed by a power peak detection module, which detects the maximum value of the instantaneous power P according to the frequency of the AC power supply, thereby obtaining the peak power Pmax. The instantaneous power P and the peak power Pmax can be divided by a divider to calculate their ratio, thus obtaining the first current coefficient Pwave.

[0094] Furthermore, the AC current Is_in can be generated internally by the control module, and IsRms can be obtained by detecting the effective value of the AC current Is_in. IsRms is multiplied by the first current coefficient Pwave through a multiplier to obtain the injected current Iinject. Finally, the injected current Iinject is injected into the AC current Is_in to obtain the output current Is_out.

[0095] Figure 5 A schematic diagram of a power waveform injection module according to an embodiment of this application is shown. Figure 5 As shown, Figure 5 Another embodiment of the power waveform injection module.

[0096] First, the control module internally generates a waveform [1+cos(2θ / freq)]. Here, freq is the frequency of the waveform. This frequency can be the same as the frequency of the AC power supply, or it can be internally set. Simultaneously, the real-time value of the AC input voltage Vdb is detected, and the angle of compressor rotation when the real-time value of the input voltage Vdb is zero is detected using zero-crossing detection. This angle of compressor rotation is then used as the phase offset to regenerate the waveform. For example, the regenerated waveform can be represented as [1+cos(2(θ+offset) / freq)].

[0097] It should be noted that the regenerated waveform can be used directly as the injection current, or it can be multiplied by the first current coefficient to obtain the injection current. For example, the regenerated waveform can be multiplied by the first current coefficient Pwave through the Gain module to obtain the injection current Iinject. Finally, the injection current Iinject is injected into the AC current Is_in to obtain the output current Is_out.

[0098] By injecting a first current component based on instantaneous power into the first current to generate an injection current, and adjusting the motor drive signal output by the intelligent power module according to the injection current to control the operation of the compressor, the embodiments of this application can improve the power factor of the air conditioner while reducing the charging and discharging current of the bus capacitor, thereby improving the life of the bus capacitor.

[0099] Figure 6 A schematic diagram of the control module according to an embodiment of this application is shown.

[0100] like Figure 6 As shown, in this embodiment of the application, a voltage waveform injection module can also be used to replace... Figure 3 The power waveform injection module in the middle determines the first current component. The difference is that in... Figure 6 In this configuration, the voltage waveform injection module can be located after the field weakening and MTPA control module, i.e., on the q-axis. The output of the field weakening and MTPA control module can serve as the input of the voltage waveform injection module, and the output of the voltage waveform injection module can be correlated with the q-axis current I. q The comparison is performed, and the comparison result is sent to the current loop regulator for adjustment. It is understood that the position of the voltage waveform injection module can also be the same as the position of the power waveform injection module; this application does not limit the positions of the voltage waveform injection module and the power waveform injection module. Figure 6 Other parts of the text and Figure 3 Similarly, I will not elaborate further.

[0101] Further, determining the first current component to be injected based on the input voltage of the AC power supply includes:

[0102] Step S31: Determine the second current coefficient based on the input voltage of the AC power supply;

[0103] Step S32: Determine the first current component to be injected based on the second current coefficient.

[0104] Further, determining the first current component to be injected based on the second current coefficient includes:

[0105] Step S33: Generate a fourth current using the control module;

[0106] Step S34: Adjust the amplitude or phase of the fourth current to obtain the fifth current;

[0107] Step S35: Determine the first current component based on the second current coefficient and the fifth current.

[0108] The first current component can be obtained by multiplying the second current coefficient and the fifth current. The fourth current may have the same waveform as the first current or be associated with the second current coefficient.

[0109] Further, determining the second current coefficient based on the input voltage of the AC power supply includes:

[0110] Step S311: Obtain the frequency of the AC power supply, and detect the peak value of the input voltage according to the frequency of the AC power supply to obtain a peak voltage with the same frequency as the AC power supply;

[0111] Step S312: Determine the second current coefficient based on the peak voltage and the input voltage.

[0112] The frequency of the AC power supply can be the frequency of the mains power. Specifically, the ratio of the peak voltage to the input voltage can be used as the second current coefficient.

[0113] Further, adjusting the amplitude or phase of the fourth current to obtain the fifth current includes:

[0114] Step S341: Adjust the amplitude of the fourth current according to the frequency of the AC power supply to obtain the effective value of the fourth current;

[0115] Step S342: Obtain the fifth current based on the effective value of the fourth current.

[0116] or,

[0117] Step S343: Detect the real-time value of the input voltage;

[0118] Step S344: Pre-set the second phase offset using the control module;

[0119] Step S345: Adjust the phase of the fourth current according to the real-time value of the input voltage and the second phase offset to obtain the fifth current.

[0120] Taking the adjustment of the amplitude of the fourth current to obtain the fifth current as an example, the effective value of the fourth current detected according to the frequency of the AC power supply can be used as the fifth current. The frequency of the AC power supply can be 50Hz, and the effective value of the fourth current can be collected every 0.02 seconds to obtain the fifth current.

[0121] Furthermore, taking the adjustment of the phase of the fourth current to obtain the fifth current as an example, the fourth current can be a sine wave, generated internally by the control module, and denoted by sinθ. The second phase offset can be θ0. When the real-time value of the input voltage is detected to be zero, θ of the fourth current can be replaced by (θ-θ0) to obtain the fifth current sin(θ-θ0).

[0122] It is worth noting that steps S341, S342 and steps S343, S344 and S345 are different schemes for determining the fifth current, which can be substituted for each other and can be selected as needed in practical applications.

[0123] Figure 7 A schematic diagram of a voltage waveform injection module according to an embodiment of this application is shown. Figure 7 As shown, Figure 7 One embodiment of the voltage waveform injection module.

[0124] First, the input voltage Vdb of the AC power supply is sampled, and the maximum value of the input voltage Vdb, VdbMax, is detected by a period peak detection module according to the frequency of the AC voltage. The input voltage Vdb and the maximum value VdbMax can be fed into a divider to calculate their ratio, thereby obtaining the second current coefficient.

[0125] Furthermore, the AC current Is_in can be generated internally by the control module, or the input current Iac of the AC power supply can be sampled and used as Is_in. Next, by performing RMS detection on the AC current Is_in, IsRms can be obtained. IsRms is multiplied by the second current coefficient using a multiplier to obtain the injected current Iinject. Finally, the injected current Iinject is injected into the AC current Is_in to obtain the output current Is_out.

[0126] Figure 8 A schematic diagram of a voltage waveform injection module according to an embodiment of this application is shown. Figure 8 As shown, Figure 8 Another embodiment of the voltage waveform injection module.

[0127] First, a sinusoidal waveform sinθ can be generated internally by the control module, and the input voltage Vdb of the AC power supply can be detected. The zero-crossing detection module detects the angle at which the real-time value of the input voltage Vdb is zero; for example, this angle could be the rotation angle of the compressor when the real-time value of the input voltage Vdb is zero. This angle can be used to correct the phase of the sinusoidal waveform sinθ, resulting in a corrected waveform. This corrected waveform is then processed by the ABS module and fed into the gain module, where it is multiplied by the second current coefficient to obtain the injected current Iinject. Finally, the injected current Iinject is injected into the AC current Is_in to obtain the output current Is_out.

[0128] It should be noted that the sine wave generated internally by the control module can also be a half-wave, which may include the positive half-cycle of the sine wave but not the negative half-cycle. There are various ways to adjust the phase of the sine wave generated internally by the control module, and this application is not limited to any particular method. For example, the periodic interruption time (i.e., step size) td and the power frequency period ts can be set first. The accumulator timer can accumulate the timing time; for example, t = t + td can be set, where t is the timing time. Next, the real-time value of the input voltage Vdb can be detected. When the real-time value of the input voltage Vdb is zero, t = tofoffset can be set, where tofoffset can be preset. Then, the waveform 1 + sin(2π*t / ts) is regenerated, and this waveform is multiplied by the second current coefficient to obtain the injected current Iinject. Finally, the injected current Iinject is injected into the AC current Is_in to obtain the output current Is_out.

[0129] By injecting a first current component based on the input voltage into the first current to generate an injection current, and adjusting the motor drive signal output by the intelligent power module according to the injection current to control the operation of the compressor, the embodiments of this application can improve the power factor of the power supply in the air conditioner while reducing the charging and discharging current of the bus capacitor, thereby improving the life of the bus capacitor.

[0130] Figure 9 A schematic diagram of the control module according to an embodiment of this application is shown.

[0131] like Figure 9 As shown, exemplarily, Figure 9The waveform in the input current can be either the second current or the fourth current. The waveforms of either the second or fourth current can be regenerated by adjusting the phase or amplitude, and the regenerated current is multiplied by the corresponding coefficient to obtain the first current component. Finally, the injected current is summed with the first current Is_in to obtain the injected current Is_out.

[0132] This application also provides a control device for an air conditioner, the control device being used to execute the control method for the air conditioner, the control device comprising: an acquisition module, configured to acquire the input voltage and instantaneous power of the AC power input in the current air conditioner; a first determination module, configured to determine a first current component to be injected based on the instantaneous power and / or the input voltage of the AC power input; an injection module, configured to generate a first current using the control module and inject the first current component into the first current to obtain an injection current; a second determination module, configured to determine a motor drive signal for the air conditioner based on the injection current; and a drive module, configured to drive the compressor to operate based on the motor drive signal.

[0133] Furthermore, the first determining module includes a third determining module and a fourth determining module.

[0134] Further, the third determining module is used to determine the first current component to be injected based on the instantaneous power of the AC power input, including: a first acquiring submodule, used to acquire the input current of the AC power input in the current air conditioner; a fifth determining module, used to determine the instantaneous power of the AC power input based on the input voltage and the input current of the AC power input; a sixth determining module, used to determine a first current coefficient based on the instantaneous power of the AC power input; and a seventh determining module, used to determine the first current component to be injected based on the first current coefficient.

[0135] Furthermore, the fourth determining module is used to determine the first current component to be injected based on the input voltage of the AC power supply, including: an eighth determining module, used to determine a second current coefficient based on the input voltage of the AC power supply; and a ninth determining module, used to determine the first current component to be injected based on the second current coefficient.

[0136] In addition, this application also provides an air conditioner, the air conditioner including the control device for the air conditioner and: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute the control method for the air conditioner.

[0137] Those skilled in the art will understand that the structure of the air conditioner does not constitute a limitation on the air conditioner, and may include more or fewer components, or combine certain components, or have different component arrangements.

[0138] in:

[0139] The processor is the control center of the air conditioner's control method. It connects various parts of the air conditioner via various interfaces and lines, and executes software programs and / or modules stored in memory, as well as calling data stored in memory, to perform various functions and process data, thereby providing overall monitoring of the air conditioner's control method operation. Optionally, the processor may include one or more processing cores; the processor can be a Central Processing Unit (CPU), or other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor. Preferably, the processor can integrate an application processor and a modem processor, where the application processor mainly handles the operating system, user interface, and applications, and the modem processor mainly handles wireless communication. It is understood that the modem processor may not be integrated into the processor.

[0140] Memory can be used to store software programs and modules. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory. Memory can primarily include a program storage area and a data storage area. The program storage area can store the operating system, at least one application program required for a given function, etc.; the data storage area can store data created based on the use of the air conditioner, etc. Furthermore, memory can include high-speed random access memory, and can also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, memory can also include a memory controller to provide the processor with access to the memory.

[0141] The air conditioner also includes a power supply for powering various components. Preferably, the power supply can be connected to the processor logic through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system. The power supply may also include one or more DC or AC power sources, a recharging system, a power fault detection circuit, a power converter or inverter, a power status indicator, or any other components.

[0142] The air conditioner may also include an input unit, which can be used to receive input digital or character information, and generate input signals related to user settings and function control via a remote control, air conditioner control panel, or through a smart home system such as a remote network, APP, or real-time voice signal input. Although not shown, the air conditioner may also include a display unit, such as a display panel for displaying air conditioner operating parameters, which will not be described in detail here.

[0143] This application also provides a storage medium storing computer program instructions thereon, which, when executed by a processor, implement the control method for an air conditioner. The storage medium may include: read-only memory (ROM), random access memory (RAM), etc.

[0144] In summary, this embodiment of the application first obtains the input voltage and instantaneous power of the AC power input in the current air conditioner, then determines the first current component to be injected based on the instantaneous power and / or the input voltage of the AC power input, then uses the control module to generate a first current, and injects the first current component into the first current to obtain the injected current, and finally determines the motor drive signal of the air conditioner based on the injected current and drives the compressor to operate based on the electrode drive signal. This allows current based on power waveform and / or voltage waveform to be injected into the air conditioner, thereby improving the power factor of the power supply in the air conditioner while reducing the charging and discharging current of the bus capacitor, thus improving the lifespan of the bus capacitor.

[0145] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0146] The control method for an air conditioner and the air conditioner provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A control method for an air conditioner, characterized in that, The air conditioner includes an AC power supply, a control module, and a compressor; the method includes: Obtain the input voltage and instantaneous power of the AC power input in the current air conditioner; The first current component to be injected is determined based on the instantaneous power of the AC power input and / or the input voltage of the AC power input. The control module generates a first current, and the first current component is injected into the first current to obtain the injected current. The motor drive signal of the air conditioner is determined based on the injected current; The compressor is driven to operate according to the motor drive signal; The step of determining the first current component to be injected based on the instantaneous power of the AC power input includes: acquiring the input current of the AC power input in the current air conditioner; determining the instantaneous power of the AC power input based on the input voltage and the input current of the AC power input; determining a first current coefficient based on the instantaneous power of the AC power input; and determining the first current component to be injected based on the first current coefficient. The step of determining the first current component to be injected based on the first current coefficient includes: generating a second current using the control module; adjusting the amplitude or phase of the second current to obtain a third current; and determining the first current component to be injected based on the first current coefficient and the third current. Alternatively, determining the first current component to be injected based on the input voltage of the AC power supply includes: determining a second current coefficient based on the input voltage of the AC power supply; determining the first current component to be injected based on the second current coefficient; wherein determining the first current component to be injected based on the second current coefficient includes: generating a fourth current using the control module; adjusting the amplitude or phase of the fourth current to obtain a fifth current; and determining the first current component based on the second current coefficient and the fifth current.

2. The method according to claim 1, characterized in that, Determining the first current coefficient based on the instantaneous power input of the AC power supply includes: The frequency of the AC power supply is obtained, and the peak value of the instantaneous power is detected based on the frequency of the AC power supply to obtain the peak power that is the same as the frequency of the AC power supply. The first current coefficient is determined based on the peak power and the instantaneous power.

3. The method according to claim 2, characterized in that, The step of adjusting the amplitude or phase of the second current to obtain the third current includes: The amplitude of the second current is adjusted according to the frequency of the AC power supply to obtain the effective value of the second current; The third current is obtained based on the effective value of the second current. or, Detect the real-time value of the input voltage; The first phase offset is determined based on the real-time value of the input voltage, wherein the first phase offset is the angle of rotation of the compressor when the real-time value of the input voltage is zero; The phase of the second current is adjusted based on the first phase offset to obtain the third current.

4. The method according to claim 1, characterized in that, The step of determining the second current coefficient based on the input voltage of the AC power supply includes: The frequency of the AC power supply is obtained, and the peak value of the input voltage is detected according to the frequency of the AC power supply to obtain a peak voltage with the same frequency as the AC power supply. The second current coefficient is determined based on the peak voltage and the input voltage.

5. The method according to claim 1, characterized in that, The step of adjusting the amplitude or phase of the fourth current to obtain the fifth current includes: The amplitude of the fourth current is adjusted according to the frequency of the AC power supply to obtain the effective value of the fourth current; The fifth current is obtained based on the effective value of the fourth current. or, Detect the real-time value of the input voltage; The second phase offset is preset using the control module; The phase of the fourth current is adjusted based on the real-time value of the input voltage and the second phase offset to obtain the fifth current.

6. An air conditioner, characterized in that, The air conditioner includes: processor; Memory used to store processor-executable instructions; The processor is configured to perform the method described in any one of claims 1 to 5.

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