Air conditioner and stepless speed regulation method of direct current motor of air conditioner

Abstract

The invention discloses an air conditioner and a stepless speed regulation method of a direct current motor of the air conditioner, and belongs to the technical field of air conditioners. The method comprises the steps that a fan control level interval output by a temperature controller is divided into a plurality of fan control level subintervals; configuring a corresponding compensation correction value for each fan control level subinterval; in a normal operation mode, the temperature controller sends out a fan control level Ut in a fan control level interval, the drive board detects a voltage signal U't transmitted by the temperature controller, the fan control level subinterval where the voltage signal U't is located is judged, the voltage signal U't is compensated and corrected according to the compensation correction value delta Uj of the corresponding subinterval, and the fan control level Ut is obtained. And controlling the rotating speed of the direct current motor of the air conditioner by taking U ''t = U't + delta Uj as a control level. The problem that attenuation of a signal line caused by a cable affects fan rotating speed control is solved, fan rotating speed control is more accurate, and an air conditioner control system is more comfortable and saves more energy.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of air conditioners, and more particularly relates to an air conditioner and a stepless speed regulation method for a direct current motor thereof. BACKGROUND

[0002] A direct current motor has the advantages of low noise, energy saving, stepless speed regulation, etc. relative to an alternating current motor. With the progress of technology, the price difference between the direct current motor and the alternating current motor is gradually reduced, and the central air conditioner fan coil gradually uses the direct current motor. The alternating current motor is often three gears of high, medium and low, and the direct current motor can be theoretically divided into countless wind speed gears. The control of the direct current motor is also relatively mature at present.

[0003] The prior art document 1 (CN105020858B) discloses a stepless speed regulation method for an indoor direct current fan in an air conditioner. For a direct current terminal fan coil, a temperature controller often outputs a 0-10V voltage signal. A drive board on the fan coil detects the voltage signal transmitted by the temperature controller, and determines the high and low speed according to the 0-10V signal voltage. The speed protocol is determined in advance, and different voltage values correspond to different speeds.

[0004] The prior art document 1 has the disadvantage that the distance from the temperature controller to the fan coil can be far, which can cause 0-10V voltage attenuation, and finally cause a certain gap between the running speed and the target speed. For example but not limited to, the temperature controller outputs 6V, which corresponds to a target speed of 800r / min. The voltage detected by the drive board on the fan coil is 5.9V, which corresponds to a speed of 780 / min, resulting in a gap of 20r / min from the target speed.

[0005] The prior art document 2 (CN112032916B) discloses a motor control system and an air conditioner, which is used for accurately controlling the speed of a direct current fan coil by a 0-10V temperature controller. The core idea is to accurately control the fan speed by a multi-stage feedback method. This scheme is relatively complex, and requires multiple sensors and multiple feedback signal lines.

[0006] There is no good solution to the problem of signal line attenuation caused by the cable in the industry. SUMMARY

[0007] To solve the problems in the prior art, the present application provides a stepless speed regulation method for an air conditioner and a direct current motor thereof, which solves the problem of fan speed control affected by cable attenuation on signal lines, makes the fan speed control more accurate, and makes the air conditioner control system more comfortable and energy-saving.

[0008] The present application adopts the following technical solutions.

[0009] A first aspect of the present invention provides a stepless speed regulation method for a DC motor of an air conditioner, comprising the following steps:

[0010] Set the fan control level range [U S ,U max ] is divided into N fan control level sub-intervals [U S ,U1],(U1,U2],……,(U N-1 ,U N ];

[0011] Configure the corresponding compensation correction value ΔU for each fan control level sub-interval i , i=1,2,…,N;

[0012] In normal operation mode, the temperature controller sends out the fan control level interval [U S ,U max ] within the fan control level U t , the driver board detects the voltage signal U' transmitted from the thermostat t , determine the voltage signal U′ t Located in the jth fan control level sub-interval, j = 1, 2, ..., N, then the jth compensation correction value ΔU j For voltage signal U′ t Make compensation correction and change U′ t =U′ t +ΔU j As the control level, the speed of the air conditioner DC motor is controlled.

[0013] Preferably, the output voltage range of the thermostat [U min ,U max ] with the limit value U S Divided into non-fan control level interval [U min ,U S ) and fan control level range [U S ,U max ], in the non-fan control level range [U min ,U S ) select a value as the self-test instruction level U a , used to guide the thermostat and driver board into self-test mode, and configure the corresponding compensation correction value ΔU in self-test mode i .

[0014] Preferably, the temperature controller issues a self-test instruction level U a , the driver board detects the voltage signal U' transmitted from the thermostat a , if the voltage decays U′ a -U aIf the voltage attenuation is not more than the preset maximum allowed attenuation value ΔU, the synchronization enters the self-check mode; if the voltage attenuation is more than the maximum allowed attenuation value ΔU, it is necessary to check whether the line connection is abnormal.

[0015] Preferably, after entering the self-check mode, the temperature controller sends N reference levels U1, U2, …, UN in turn within the fan control level interval [U S ,U max ] according to a set timing. N , N = U max ;

[0016] According to the timing, the drive board detects the voltage signals U'1, U'2, …, U'N sent by the temperature controller. N-1 , N ;

[0017] The voltage attenuations under the reference levels are calculated with the deviation value ΔU i = U i -U' i , and the i-th deviation value ΔU i is taken as the compensation correction value of the i-th fan control level sub-interval.

[0018] Preferably, if the compensation correction values of the adjacent fan control level sub-intervals are the same in the last self-check mode, the self-check this time combines the adjacent fan control level sub-intervals, and one reference level is correspondingly reduced.

[0019] Preferably, the control level U" t is checked, if the control level U" t is higher than the maximum level U max of the working range of the temperature controller, the control level U" max is updated with the maximum level U t of the working range of the temperature controller; if the control level U" t is lower than the limit value U S and higher than the limit value U S , the difference between the limit value U S and the preset maximum allowed attenuation value ΔU, the control level U" t is updated with the limit value U .

[0020] Preferably, after the air conditioner is powered on, the temperature controller enters the self-check mode in the air conditioner shutdown state, sends a self-check instruction level U a , and generates a compensation correction value for the voltage attenuation amount.

[0021] After the air conditioner is powered on, the compensation correction value obtained in the last self-check process is used to compensate the voltage signal U t ' detected by the drive board from the temperature controller, so as to accurately control the fan speed.

[0022] Preferably, the temperature controller outputs a voltage ranging from 0 to 10V, the fan control level interval [2V, 10V] and the non-fan control level interval [0V, 2V) are divided;

[0023] The self-checking instruction level U a is set to 1V;

[0024] The maximum allowed attenuation value ΔU is 0.3V, and the drive board detects that the level is between [0.7V, 1V], and then synchronously enters the self-checking mode.

[0025] The second aspect of the present application provides an air conditioner, comprising: a direct current motor, a drive board connected with the direct current motor, and a temperature controller outputting a voltage signal to the drive board; the air conditioner runs the stepless speed regulation method of the air conditioner direct current motor as described in the first aspect.

[0026] The third aspect of the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to realize the stepless speed regulation method of the air conditioner direct current motor as described in the first aspect.

[0027] Compared with the prior art, the present application has at least the following beneficial effects: for the stepless speed regulation temperature controller, the voltage output to the fan coil is deviated from the actual voltage value detected by the fan coil side, and the present application provides a method for adaptively detecting voltage attenuation and correcting the same, the deviation between the preset value and the actual value is used for correction, the attenuation caused by the cable to the signal line is overcome, and the fan speed control is accurate and reliable. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a flow chart of the stepless speed regulation method of the air conditioner direct current motor provided according to the embodiment of the present application;

[0029] Figure 2 is a wiring diagram of the air conditioner provided according to the embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. The described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the spirit of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0031] Embodiment 1 of the present application provides a stepless speed regulation method of an air conditioner direct current motor, comprising the following steps:

[0032] The fan control level interval [US ,U max ] is divided into N fan control level sub-intervals [U S ,U1],(U1,U2],……,(U N-1 ,U N ];

[0033] Configure the corresponding compensation correction value ΔU for each fan control level sub-interval i , i=1,2,…,N;

[0034] In normal operation mode, the temperature controller sends out the fan control level interval [U S ,U max ] within the fan control level U t , the driver board detects the voltage signal U' transmitted from the thermostat t , judge the voltage signal U′ t Located in the jth fan control level sub-interval, j = 1, 2, ..., N, then the jth deviation value ΔU j For voltage signal U′ t Make compensation correction and change U″ t =U′ t +ΔU j As the control level, the speed of the air conditioner DC motor is controlled.

[0035] like Figure 1 As shown, embodiment 2 of the present invention provides a stepless speed regulation method for a DC motor of an air conditioner. As one of the outstanding essential features of the present invention, embodiment 2 provides a method for configuring a corresponding compensation correction value ΔU for each fan control level sub-interval based on embodiment 1. i , i=1,2,…,N specific method.

[0036] The stepless speed regulation method of the air conditioner DC motor specifically comprises the following steps:

[0037] Step 1: Set the thermostat output voltage range [U min ,U max ] with the limit value U S Divided into non-fan control level interval [U min ,U S ) and fan control level range [U S ,U max ], where U min is the minimum level of the thermostat working range, U max The maximum level of the thermostat working range; in the non-fan control level range [U min ,U S ) select a value as the self-test instruction level U a , that is U a∈[U min ,U S )。

[0038] Step 2: Set the self-check mode on the temperature controller, the temperature controller sends a self-check instruction level U a , the drive board on the fan coil detects the voltage signal U' sent by the temperature controller a , if the voltage attenuation U' does not exceed the preset maximum allowable attenuation value ΔU, then it synchronously enters the self-check mode. a -U a

[0039] It can be understood that, considering the case of long connection line, the maximum allowable attenuation value ΔU has been set to be large enough, and in the case of normal wiring, it will not exceed the maximum attenuation value. If it exceeds the maximum allowable attenuation value ΔU, it needs to check the line connection, whether the interface is rusty or the contact is poor, causing too large impedance, so that the level exceeds the maximum attenuation value or even cannot receive the level.

[0040] Step 3: After entering the self-check mode, the temperature controller sends N reference levels U1, U2, …, UN in the fan control level interval [U S ,U max ] according to the set time sequence, wherein U N =U N ; according to the time sequence, the drive board on the fan coil detects the voltage signal U'1, U'2, …, UN sent by the temperature controller, and U'1, U'2, …, UN, and the voltage attenuation under each reference level is calculated, i.e. the deviation value ΔU1, ΔU2, …, ΔUN, i.e. ΔU1=U1-U'1, ΔU2=U2-U'2, …, ΔUN=UN-UN, i=1, 2, …, N. max N-1 N i i i N .

[0041] Step 4: Divide the fan control level interval [U N ,U S ] into N fan control level subintervals [U max ,U1], (U1, U2], …, (U S ,U N-1 ], and take the i-th deviation value ΔU N as the compensation correction value of the i-th fan control level subinterval. i

[0042] ​​​​​​​​Preferably but not restrictively, the lengths of the N fan control level subintervals can be equal or unequal; if the compensation correction values ​​of adjacent fan control level subintervals are the same in the previous self-test mode, this self-test merges the adjacent fan control level subintervals, correspondingly reducing one reference level.

[0043] Step 5: After exiting the self-test mode and entering the normal operation mode, the thermostat will send out the fan control level interval [U S ,U max ] within the fan control level U t The driver board on the fan coil detects the voltage signal U' transmitted from the thermostat t , judge the voltage signal U′ t Located in the jth fan control level sub-interval, j = 1, 2, ..., N, then the jth deviation value ΔU j For voltage signal U′ t Make compensation correction and change U t =U′ t +ΔU j As the control level, the control level U t Control the speed of the air conditioner DC motor.

[0044] Preferably, but not limited to, the control level U″ t Check, if the control level U″ t Higher than the maximum level U of the thermostat working range max , then the maximum level U of the thermostat working range max Update control level U″ t ; If the control level U″ t Fall into (U S -ΔU,U min ], that is, below the limit value U S And higher than the limit U S The difference from the preset maximum permissible attenuation value ΔU is calculated as the limit value U S Update control level U″ t .

[0045] Preferably, but not restrictively, after the air conditioner is powered on, in the off state, the thermostat enters the self-test mode and issues a self-test instruction level U a , generating a compensation correction value for the voltage attenuation. After the air conditioner is turned on, the compensation correction value obtained in the previous correction process is used to detect the voltage signal U' transmitted from the thermostat on the driver board of the fan coil. t Compensate and accurately control the fan speed.

[0046] In order to more clearly introduce the outstanding substantial features of the present application and the significant progress brought to the prior art, an application example of implementing the present application is introduced as follows. Specifically, embodiment 3 of the present application provides a stepless speed regulation method for a direct current motor of an air conditioner, comprising the following steps:

[0047] Step 1: The output voltage range of the temperature controller is 0-10V, and the 0-10V level is divided into a fan control level interval and a non-fan control level interval. Preferably but not limitedly, the fan control level interval is [2V, 10V], and the non-fan control level interval is [0V, 2V).

[0048] The self-checking instruction level U is selected in the non-fan control level interval [0V, 2V). a Further preferably but not limitedly, a set difference is maintained with the fan control level interval, for example but not limitedly, the self-checking instruction level U is set to 1V. a

[0049] It is worth noting that, as one of the outstanding substantial features of the present application, a relatively low voltage value is abandoned, effectively avoiding fan misoperation under power grid fluctuation. [U S , U max ] corresponds to 0%-100% of the fan speed, and in embodiment 3, 2V is preferably but not limitedly used, so that a certain difference between the speed control level and the self-checking level is also achieved, avoiding misoperation.

[0050] Step 2: Set the self-checking mode: set the self-checking mode on the temperature controller, and the temperature controller sends the self-checking instruction level U a , i.e. 1V, and the drive board detects that the level is within the self-checking instruction level range [U a -ΔU, U a ], then the self-checking mode is entered synchronously. ΔU is the maximum allowed attenuation value, preferably but not limitedly, the maximum allowed attenuation value ΔU is 0.3V, and the drive board detects that the level is between [0.7V, 1V], then the self-checking mode is entered synchronously.

[0051] ​Step 3: After entering the self-check mode, the temperature controller sends out 8 reference levels U1=3V, U2=4V, U3=5V, U4=6V, U5=7V, U6=8V, U7=9V, U8=10V in sequence according to the time sequence; the drive board detects the level values after the attenuation of the 8 reference levels in sequence according to the time sequence, for example but not limited to, U'1=2.96V, U'2=3.94V, U'3=4.94V, U'4=5.93V, U'5=6.92V, U'6=7.92V, U'7=8.91V, U'8=9.90V; 8 deviation values ΔU1=0.04V, ΔU2=0.06V, ΔU3=0.06V, ΔU4=0.07V, ΔU5=0.08V, ΔU6=0.08V, ΔU7=0.09V, ΔU8=0.10V are obtained.

[0052] Step 4: The fan control level interval [2V, 10V] is divided into 8 fan control level sub-intervals [2V, 3V], (3V, 4V], …, (9V, 10V] by using the 8 reference levels U1=3V, U2=4V, U3=5V, U4=6V, U5=7V, U6=8V, U7=9V, U8=10V; the i-th deviation value ΔUi, i=1, 2, …, N is used as the compensation correction value of the i-th fan control level sub-interval. i The i-th deviation value ΔUi, i=1, 2, …, N is used as the compensation correction value of the i-th fan control level sub-interval.

[0053] Step 5: After that, when the drive board detects the level U t less than or equal to U1=3V, the control level U" t is the detection value U t +ΔU1, when the drive board detects the level U t between (U1, U2], i.e. between (3V, 4V], the control level U" t is the detection value U t +ΔU2, …, when the drive board detects the level U t between (U7, U8], i.e. between (9V, 10V], the control level U" t is the detection value U t +ΔU8.

[0054] Preferably but not limitedly, the corrected level value also needs to be processed, when the level is higher than the upper limit, the level value is considered as the upper limit of the speed regulation, if the level is lower than the lower limit of the speed regulation and the difference is not greater than the maximum attenuation value ΔU, the level is considered as the lower limit of the speed regulation. For example, the corrected level value is greater than 10V, the level value is 10V, if the level value is close to slightly less than 2V, the level value is processed as 2V.

[0055] For example, Figure 2As shown, embodiment 4 of the present invention provides an air conditioner, comprising: a DC motor, a temperature controller, and a drive board arranged on a fan coil unit and connected to the DC motor; the air conditioner operates according to the stepless speed regulation method of the DC motor of the air conditioner described in embodiment 1, 2 or 3.

[0056] Specifically, the output voltage range of the thermostat [U min ,U max ] with the limit value U S Divided into non-fan control level interval [U min ,U S ) and fan control level range [U S ,U nax ]; The temperature controller is used to send a self-test instruction level U to the driver board in the self-test mode a , U a ∈[U min ,U S ), and N reference levels U1, U2, ..., U N , and in normal operating mode, sends the fan control level U to the driver board t , U t ∈[U S ,U max ].

[0057] The driver board is in self-test mode, corresponding to the N reference levels U1, U2, ..., U sent by the temperature controller. N , detect the voltage signal U'1, U'2, ..., U' transmitted by the thermostat N-1 , U′ N , the main control unit of the driver board calculates the voltage attenuation under each reference level and obtains N corresponding deviation values ​​ΔU1, ΔU2, ..., ΔU N .

[0058] In normal operation mode, the driver board detects the voltage signal U' transmitted from the thermostat t , determine the voltage signal U′ t Located in the jth fan control level sub-interval, the jth deviation value ΔU j For voltage signal U′ t Make compensation correction and change U″ t =U′ t +ΔU j As the control level, it controls the speed of the air conditioner DC motor.

[0059] Embodiment 5 of the present invention provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the stepless speed regulation method of the air conditioner DC motor according to embodiment 1, 2 or 3.

[0060] As the prominent essential feature of the present application, the preset voltage is compared with the detected voltage to determine the speed regulating voltage attenuation amount and correct it, so that the complicated closed-loop feedback control, especially the complicated multi-stage feedback control, is not needed, the control device and logic are greatly simplified, and the problem of the fan rotating speed control affected by the output voltage attenuation of the temperature controller is solved. The fan rotating speed control is accurate, and the air conditioner control system is more comfortable and energy-saving.

[0061] It is worth noting that in the embodiments of the present application, "step + number" is only a kind of expression for clearly describing the specific implementation of the stepless speed regulating method of the direct current motor of the air conditioner, and is not an absolute limit to the order of each step. Under the guidance of the core concept of the present application, the order of the steps is exchanged to obtain the same or similar technical effects, which all fall within the scope of the present application.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and not to limit it. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can still be modified or replaced by equivalents without departing from the spirit and scope of the present application. Any modification or equivalent replacement that does not depart from the spirit and scope of the present application should be covered within the protection scope of the claims of the present application.

Claims

1. A stepless speed regulation method for a DC motor of an air conditioner, characterized in that: The following steps are involved: Set the fan control level range [U S ,U max ] is divided into N fan control level sub-intervals [U S ,U1],(U1,U2],……,(U N-1 ,U N ]; Configure the corresponding compensation correction value ΔU for each fan control level sub-interval i , i=1,2,…,N; In normal operation mode, the temperature controller sends out the fan control level interval [U S ,U max ] within the fan control level U t , the driver board detects the voltage signal U' transmitted from the thermostat t , determine the voltage signal U′ t Located in the jth fan control level sub-interval, j = 1, 2, ..., N, then the jth compensation correction value ΔU j For voltage signal U′ t Make compensation correction and change U″ t =U′ t +ΔU j As the control level, the speed of the air conditioner DC motor is controlled.

2. The method for stepless speed regulation of a DC motor of an air conditioner according to claim 1, characterized in that: The output voltage range of the thermostat [U min ,U max ] with the limit value U S Divided into non-fan control level interval [U min ,U S ) and fan control level range [U S ,U max ], in the non-fan control level range [U min ,U S ) select a value as the self-test instruction level U a , used to guide the thermostat and driver board into self-test mode, and configure the corresponding compensation correction value ΔU in self-test mode i .

3. The method for stepless speed regulation of a DC motor of an air conditioner according to claim 2, characterized in that: The temperature controller sends a self-test command level U a , the driver board detects the voltage signal U' transmitted from the thermostat a , if the voltage decays U′ a -U a If the attenuation does not exceed the preset maximum allowable value ΔU, the system will enter the self-test mode synchronously. If the attenuation exceeds the maximum allowable value ΔU, it is necessary to check whether the line connection is abnormal.

4. The method for stepless speed regulation of a DC motor of an air conditioner according to claim 2 or 3, characterized in that: After entering the self-test mode, the thermostat will adjust the fan control level range [U S ,U max ] N reference levels U1, U2, ..., U N , where U N =U max ; According to the timing, the driver board detects the voltage signals U'1, U'2, ..., U' transmitted by the thermostat. N-1 , U′ N ; With deviation value ΔU i =U i -U′ i Calculate the voltage attenuation at each reference level and set the i-th deviation value ΔU i As the compensation correction value of the i-th fan control level sub-interval.

5. The method for stepless speed regulation of a DC motor of an air conditioner according to claim 3, characterized in that: If the compensation correction values ​​of adjacent fan control level sub-intervals are the same in the previous self-test mode, the adjacent fan control level sub-intervals will be merged in this self-test, and one reference level will be reduced accordingly.

6. A stepless speed regulation method for a DC motor of an air conditioner according to any one of claims 1 to 3, characterized in that: For control level U″ t Check, if the control level U″ t Higher than the maximum level U of the thermostat working range max , then the maximum level U of the thermostat working range max Update control level U″ t ; If the control level U t "" Below the limit U S And higher than the limit U S The difference between the preset maximum allowable attenuation value ΔU is calculated as the limit value U S Update control level U″ t .

7. A stepless speed regulation method for a DC motor of an air conditioner according to claim 2 or 3, characterized in that: After the air conditioner is powered on, when the air conditioner is turned off, the thermostat enters the self-test mode and sends a self-test command level U a , generating a compensation correction value for the voltage attenuation; After the air conditioner is turned on, the compensation correction value obtained in the previous self-test process is used to detect the voltage signal U' transmitted from the thermostat on the driver board. t Compensate and accurately control the fan speed.

8. The method for stepless speed regulation of a DC motor of an air conditioner according to claim 3, characterized in that: The output voltage range of the thermostat is 0~10V, which is divided into the fan control level interval [2V, 10V] and the non-fan control level interval [0V, 2V); Set the self-test instruction level U a Set to 1V; The maximum allowable attenuation value ΔU is 0.3V. When the driver board detects that the voltage level is between [0.7V, 1V], it will enter the self-test mode synchronously.

9. An air conditioner comprising: A DC motor, a driving board connected to the DC motor, and a temperature controller that outputs a voltage signal to the driving board; characterized in that the air conditioner runs the stepless speed regulation method of the DC motor of the air conditioner according to any one of claims 1 to 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the method for stepless speed regulation of a DC motor of an air conditioner according to any one of claims 1 to 8 is implemented.

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