Motor control device and air conditioner

Abstract

The application discloses a motor control device and an air conditioner. The motor control device comprises: a variable frequency topology circuit, which is used for inverting a bus direct-current power supply into a three-phase voltage to supply power to a drain pump motor; and a drive controller, which is configured to drive and control the variable frequency topology circuit and enter an automatic blockage cleaning process when the drain pump appears to be locked and is still locked after the lock lasts for a preset time. The automatic blockage cleaning process comprises the following: switching the acceleration of the drain pump to be a maximum preset acceleration, and controlling the drain pump to enter a positive and negative rotation cycle mode; in the positive and negative rotation cycle mode, the acceleration of each rotation of the drain pump in a cycle sequence is sequentially decreased, and the rotation action time in each rotation is related to the current acceleration of the drain pump, a first preset acceleration and a preset time. The application can control the drain pump to perform positive and negative rotation cycles when the drain pump is locked, and change the load torque of the drain pump in each rotation in the positive and negative rotation cycles, so that the effect of removing dirty blockage of the drain pump is achieved.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, and in particular to a motor control device and an air conditioner. Background Technology

[0002] In related technologies, when an air conditioner is in cooling mode, water vapor in the air encounters the low-temperature evaporator, forming condensate that flows into the drip tray of the indoor unit. The condensate is then pumped out of the drip tray by a drain pump through a drain pipe to the outside. During the condensation process, impurities such as lint, dust, and hair from the low-temperature evaporator and the air are also collected in the drip tray. Over time, these impurities accumulate in the drip tray, becoming increasingly adsorbed and deposited. Consequently, during drainage, these impurities can be sucked into the drain pump inlet, causing blockage and preventing the drain pump from draining properly, or even leading to pump malfunction. Summary of the Invention

[0003] In response to the problems mentioned in the background art, this application provides a motor control device that controls the drainage pump to perform forward and reverse rotation cycles when the drainage pump becomes stuck. The acceleration of the drainage pump is different during forward and reverse rotation, and the rotation time of forward and reverse rotation is related to the corresponding acceleration. By using the difference in acceleration, the load torque is changed, thereby achieving the effect of clearing dirt and blockage from the drainage pump.

[0004] To achieve the above-mentioned objectives, the present invention employs the following technical solution: Some embodiments of this application relate to a motor control device. The frequency converter topology circuit is used to invert the DC power supply from the bus to a three-phase voltage to power the drainage pump motor. A drive controller is configured to drive and control the variable frequency topology circuit, and to initiate an automatic unblocking process when the drainage pump stalls and remains stalled for a preset time. The automatic unblocking process includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation action time under each rotation is related to the current acceleration of the drainage pump, the first preset acceleration, and the preset time. Wherein, the maximum preset acceleration is the maximum acceleration value that can clear the blockage, and the first preset acceleration is the minimum acceleration value that can clear the blockage.

[0005] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: When a stall occurs, a preset time needs to be waited to avoid misjudgment. If the stall still occurs after the preset time, an automatic process to clear the dirt and grime is required. First, in order to overcome the resistance of the dirt and grime to the maximum extent, the acceleration is set to the maximum preset acceleration. Then, the drain pump is controlled to enter a forward and reverse rotation cycle mode. The reverse inertial force generated when switching between forward and reverse rotation and the centrifugal force when reversing the rotation are used to shake off the impurities or dirt attached to the impeller surface, so as to achieve self-cleaning of the drain pump.

[0006] During forward and reverse rotation, the acceleration of rotation decreases sequentially according to the number of cycles, ensuring that a larger acceleration is used when there is more dirt and a smaller acceleration is used when there is less dirt and blockage. The acceleration can be adaptively adjusted according to the dirt and blockage situation to change the load torque and realize the automatic clearing of blockage by the drainage pump.

[0007] In some embodiments of this application, the maximum preset acceleration and the first preset acceleration are preset according to different drainage pump motors; The larger the ratio K of the maximum preset acceleration to the first preset acceleration, the more rotational cycles there are in each rotation in the cyclic sequence.

[0008] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: The maximum preset acceleration and the first preset acceleration are determined based on the drainage pump's ability to clear blockages. Therefore, the larger the ratio K of the maximum preset acceleration to the first preset acceleration, the greater the degree of blockage in the drainage pump. As a result, the more times the pump needs to rotate in both forward and reverse directions, the longer the forward and reverse rotation will be applied to the drainage pump, which helps to clear the blockage.

[0009] In some embodiments of this application, the acceleration between adjacent rotations of the drainage pump in the cycle sequence differs by a fixed difference. Wherein, the fixed difference is the ratio of the difference between the maximum preset acceleration and the first preset acceleration to K.

[0010] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: During the unclogging process of the drainage pump, a large acceleration is first used to apply a large torque to unclogging the drainage pump. As the unclogging process continues, the acceleration is reduced at fixed intervals to achieve continuous unclogging of the drainage pump while stabilizing the speed reduction, thus ensuring stable operation of the drainage pump.

[0011] In some embodiments of this application, the automatic unblocking process further includes: The step of checking whether the drainage pump is blocked after the automatic unblocking process is completed; If the drain pump is still blocked, a re-automatic unblocking process can be initiated, which includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation duration of each rotation is related to the current acceleration of the drainage pump, the second preset acceleration, and the preset time. Wherein, the second preset acceleration is less than the first preset acceleration; If the drain pump remains blocked after the automatic unblocking process is completed, an alarm will be triggered.

[0012] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: If blockages persist after the automatic unblocking process is completed, a second automatic unblocking process will be initiated to continuously unblock the drainage pump and ensure complete unblocking.

[0013] In some embodiments of this application, the maximum preset acceleration, the first preset acceleration, and the second preset acceleration are preset according to different drainage pump motors; During the automatic unblocking process, the larger the ratio K of the maximum preset acceleration to the first preset acceleration, the more rotations there are in the cycle sequence during the automatic unblocking process. During the automatic deblocking process, the larger the ratio K' of the maximum preset acceleration to the second preset acceleration, the more rotations there are in the cycle sequence during the automatic deblocking process.

[0014] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: If blockage still exists after the automatic unblocking process is completed, when entering the re-automatic unblocking process, the second preset acceleration is set to be less than the first preset acceleration, increasing the number of rotations in the re-automatic unblocking stage and increasing the unblocking capacity of the drainage pump.

[0015] In some embodiments of this application, during the automatic unblocking process, the acceleration difference between adjacent rotations of the drain pump in the cycle sequence is a first fixed difference, the first fixed difference being the ratio of the difference between the maximum preset acceleration and the first preset acceleration to K; During the automatic unblocking process, the acceleration difference between adjacent rotations of the drain pump in the cycle sequence is a second fixed difference, which is the ratio of the difference between the maximum preset acceleration and the second preset acceleration to K'.

[0016] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: During the unclogging process of the drainage pump, a large acceleration is first used to apply a large torque to unclogging the drainage pump. As the unclogging process continues, the acceleration is reduced at fixed intervals to achieve continuous unclogging of the drainage pump while stabilizing the speed reduction, thus ensuring stable operation of the drainage pump.

[0017] In some embodiments of this application, when the drain pump is initially determined to be stalled before entering the automatic unblocking process, the acceleration of the drain pump is switched to the first preset acceleration.

[0018] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: When clearing blockages in a drain pump, the pump's acceleration is switched to the first preset acceleration at the initial stage of blockage. This setting can balance energy saving and blockage clearing.

[0019] In some embodiments of this application, the motor control device further includes: A current detection unit is used to detect the motor current of the drainage pump; When the speed of the drainage pump does not reach the specified speed and / or the motor current reaches the upper limit of the specified current value, the drive controller determines that the drainage pump is stalled.

[0020] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: When a drainage pump becomes clogged, the current value corresponding to the specified speed during the operation of the drainage pump will increase, or the speed will decrease. Therefore, current or speed can be used to measure whether the drainage pump is clogged.

[0021] The system uses both current and speed to determine whether the drainage pump is stalled, ensuring the accuracy of the stall detection.

[0022] This application also relates to an air conditioner, comprising: The refrigerant circulation loop allows the refrigerant to circulate within a loop consisting of the compressor, condenser, expansion valve, and evaporator. A drip tray, used to collect condensate produced when the air conditioner is in cooling operation; A drain pump, installed inside the water receiving pan, is used to drain the condensate in the water receiving pan to the outside; The frequency converter topology circuit is used to invert the DC power supply from the bus to a three-phase voltage to power the drainage pump motor. A drive controller is configured to drive and control the variable frequency topology circuit, and to initiate an automatic unblocking process when the drainage pump stalls and remains stalled for a preset time. The automatic unblocking process includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation action time under each rotation is related to the current acceleration of the drainage pump, the first preset acceleration, and the preset time. Wherein, the maximum preset acceleration is the maximum acceleration value that can clear the blockage, and the first preset acceleration is the minimum acceleration value that can clear the blockage.

[0023] The technical solutions involved in the above embodiments have the following advantages or beneficial effects: When a stall occurs, a preset time needs to be waited to avoid misjudgment. If the stall still occurs after the preset time, an automatic process to clear the dirt and grime is required. First, in order to overcome the resistance of the dirt and grime to the maximum extent, the acceleration is set to the maximum preset acceleration. Then, the drain pump is controlled to enter a forward and reverse rotation cycle mode. The reverse inertial force generated when switching between forward and reverse rotation and the centrifugal force when reversing the rotation are used to shake off the impurities or dirt attached to the impeller surface, so as to achieve self-cleaning of the drain pump.

[0024] During forward and reverse rotation, the acceleration of rotation decreases sequentially according to the number of cycles, ensuring that a larger acceleration is used when there is more dirt and a smaller acceleration is used when there is less dirt and blockage. The acceleration can be adaptively adjusted according to the dirt and blockage situation to change the load torque and realize the automatic clearing of blockage by the drainage pump.

[0025] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 Here is a schematic diagram of an existing air conditioner. Figure 2 A schematic diagram showing a drainage pump placed in a water receiving tray; Figure 3 A schematic block diagram illustrating the application of the motor control device proposed in this application; Figure 4 This is a circuit diagram showing the inverter topology circuit for a motor and the connection to the motor. Figure 5 This is a flowchart illustrating the determination of pump stall in an embodiment of the motor control device proposed in this application; Figure 6 The process of entering the automatic unblocking process according to the embodiment of the motor control device proposed in this application. Figure 1 ; Figure 7 This is a flowchart of the automatic unblocking process in an embodiment of the motor control device proposed in this application; Figure 8 The process of entering the automatic unblocking process according to the embodiment of the motor control device proposed in this application. Figure 2 ; Figure 9 The process for entering the automatic deblocking process according to the embodiment of the motor control device proposed in this application. Figure 1 ; Figure 10 The process for entering the automatic deblocking process according to the embodiment of the motor control device proposed in this application. Figure 2 ; Figure label: 10. Drive controller; 20. Drain pump; 30. Variable frequency topology circuit; 31. Rectifier circuit; 32. PFC circuit; 33. Inverter unit; 40. Water receiving tray. Detailed Implementation

[0028] 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 some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this application.

[0030] 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 technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0031] 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 or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. 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 embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0034] The basic working principle of an air conditioner is described below.

[0035] See Figure 1 An air conditioner executes a refrigeration cycle using a compressor, condenser, expansion valve, and evaporator. The refrigeration cycle involves a series of processes, including compression, condensation, expansion, and evaporation, to cool or heat an indoor space.

[0036] Low-temperature, low-pressure refrigerant enters the compressor, which compresses it into a high-temperature, high-pressure refrigerant gas and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0037] The expansion valve expands the high-temperature, high-pressure liquid refrigerant that condenses in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the expanded refrigerant in the expansion valve and returns the low-temperature, low-pressure refrigerant gas to the compressor. The evaporator achieves its cooling effect by utilizing the latent heat of refrigerant evaporation to exchange heat with the material being cooled. Throughout the cycle, the air conditioner regulates the temperature of the indoor space.

[0038] The outdoor unit of an air conditioner refers to the part of the refrigeration cycle that includes the compressor and the outdoor heat exchanger. The indoor unit of an air conditioner includes the indoor heat exchanger, and an expansion valve can be provided in either the indoor or outdoor unit.

[0039] The indoor and outdoor heat exchangers function as either condensers or evaporators. When the indoor heat exchanger is used as a condenser, the air conditioner functions as a heater in heating mode; when the indoor heat exchanger is used as an evaporator, the air conditioner functions as a cooler in cooling mode.

[0040] The drain pump 20 is a component of the indoor unit of the air conditioner. In the cooling mode of the air conditioner, when the airflow flows over the surface of the indoor heat exchanger, which acts as an evaporator, condensate will be generated on its surface. Generally, a drip tray 40 is installed below the indoor heat exchanger to receive this condensate.

[0041] See Figure 2 The drain pump 20 is installed inside the water collection pan 40 and is used to draw the condensate in the water collection pan 40 to the outside of the air conditioner indoor unit when the drain pump 20 is started.

[0042] Over time, foreign objects such as lint and hair will accumulate in the water collection tray 40. When the drain pump 20 drains water, these foreign objects in the water collection tray 40 may enter the drain pump 20, which may cause the drain pump 20 to become dirty and clogged.

[0043] Therefore, in order to solve the problem of dirt and grime buildup inside the water tray 40 of existing air conditioners causing blockage of the drain pump 20, this application provides a motor control device.

[0044] See Figure 3 The motor control device includes a drive controller 10 and a frequency converter topology circuit 30. The drive controller 10 can control the frequency converter topology circuit 30 and can clear the blockage through an automatic unblocking strategy when the drain pump 20 is clogged, thus ensuring the normal operation of the drain pump.

[0045] Variable frequency topology circuit structure See Figure 4 It shows the structure of the frequency conversion topology circuit 30.

[0046] See Figure 4At the very front, the input terminal of the rectifier circuit 31 is connected to a (single-phase or three-phase) AC power supply. The rectifier circuit 31 is used to rectify the AC power supplied by the AC power supply to obtain rectified pulsating waves.

[0047] The rectifier circuit 31 is a single-phase bridge rectifier bridge composed of four diodes, or a three-phase bridge rectifier bridge composed of six diodes.

[0048] See also Figure 4 The PFC circuit 32 is connected between the output terminal of the rectifier circuit 31 and the electrolytic capacitor E. The PFC circuit 32 is used to perform power factor correction on the power supply.

[0049] The electrolytic capacitor E is connected in parallel with the load, which can refer to the motor of the drainage pump 20.

[0050] That is, after the AC power is rectified by the rectifier circuit 31, it passes through the PFC circuit 32 and then drives the inverter unit 33 to supply power to the load.

[0051] See also Figure 4 The power output from the rectifier circuit 31 serves as the input power supply for the PFC circuit 32, and has a positive input power supply terminal and a negative input power supply terminal.

[0052] The PFC circuit 32 includes an inductor L, a switching transistor Q1, and a diode D1.

[0053] The positive terminal of the input power supply of PFC circuit 32 is connected to one end of inductor L, and the other end of inductor L is divided into two paths: the first path and the second path.

[0054] The first path is connected to the collector of the switching transistor Q1, and the second path is connected to the anode of the diode D1.

[0055] The cathode of diode D1 is the output terminal of PFC circuit 32. One end of electrolytic capacitor E is connected to the cathode of diode D1, and the other end of electrolytic capacitor E is connected to the emitter of switching transistor Q1, the negative terminal of the input power supply of PFC circuit 32, and ground.

[0056] The rectifier circuit 31 and the electrolytic capacitor E are both used in conjunction with the PFC circuit 32.

[0057] The PFC circuit 32 can correct the power factor of the power supply and boost the pulsating wave after rectification to provide a stable DC bus voltage Vdc to the electrolytic capacitor E.

[0058] The DC bus voltage Vdc output by the PFC circuit 32 is supplied to the inverter unit 33, which inverts the DC bus voltage into three-phase AC power used by the water supply and drainage pump 20 motor.

[0059] The aforementioned variable frequency topology circuit 30 is used to power the motor of the drainage pump 20, and the drive controller 10 is configured to drive and control the variable frequency topology circuit 30 (e.g., drive and control the switching transistor Q1 in the PFC circuit 32 and the switching transistor in the inverter unit 33), and also execute the automatic unblocking strategy of the drainage pump 20 when it is stalled.

[0060] The following will be combined Figures 5 to 10 Describes the automatic congestion clearing strategy.

[0061] In some embodiments of this application, the drain pump 20 may become blocked after long-term use. If this blockage is not dealt with in time, it will not only affect the drainage of the drain pump 20, but may also pose a safety risk of damaging the drain pump 20. Therefore, it needs to be dealt with in a timely manner.

[0062] In some embodiments of this application, a specified rotational speed and a specified current value can be set. When the drain pump 20 is clogged, the rotational speed will decrease, and correspondingly, the current will increase accordingly.

[0063] In some embodiments of this application, for example, the specified speed can be set to 600 rpm, and the specified current value can be the maximum motor current ismax.

[0064] In some embodiments of this application, the current rotation speed of the drainage pump 20 can be obtained and compared with a specified rotation speed. If the current rotation speed is lower than the specified rotation speed or the current rotation speed deviates from the specified rotation speed by a certain margin, it indicates that the drainage pump 20 is currently in a stalled state.

[0065] In some embodiments of this application, the current current value of the drainage pump 20 can be obtained and compared with a specified current value. If the current current value is less than the specified current value or the current current value deviates from the specified current value by a certain margin, it indicates that the drainage pump 20 is currently in a stalled state.

[0066] In some embodiments of this application, see Figure 5 The current current value and current speed of the drainage pump 20 can be combined to determine whether the drainage pump 20 is currently in a stalled state.

[0067] In some embodiments of this application, see Figure 6 When it is determined that the drainage pump 20 is currently in a blocked state, in order to avoid misjudgment, a preset time ts is set. That is, if the drainage pump 20 is still in a blocked state after ts time after the blockage, the automatic unblocking strategy is entered.

[0068] In some embodiments of this application, before using the automatic unblocking strategy to perform the automatic unblocking process, it is necessary to pre-set the maximum preset acceleration arefmax and the first preset acceleration arefmin of the drain pump 20. The maximum preset acceleration arefmax is the maximum acceleration value that the drain pump 20 can clear the dirt and blockage during the test, and the first preset acceleration arefmin is the minimum acceleration value that the drain pump 20 can clear the dirt and blockage during the test.

[0069] The first preset acceleration arefmin is less than the maximum preset acceleration arefmax.

[0070] Different drainage pumps 20 have different maximum preset accelerations arefmax and first preset accelerations arefmin, and thus, they will also have different ratios K of maximum preset accelerations arefmax and first preset accelerations arefmin.

[0071] In some embodiments of this application, see Figure 7 In the initial stage of entering the automatic unblocking strategy, the acceleration of the drainage pump 20 is switched to the maximum preset acceleration arefmax, and the drainage pump 20 is controlled to enter the forward and reverse rotation cycle mode.

[0072] By using the maximum preset acceleration arefmax, the force exerted on impurities on the impeller of the drainage pump 20 during the initial stage of unclogging is increased, which helps to unclogging. The drainage pump 20 is controlled to run alternately in forward and reverse directions. The reverse inertial force generated when switching between forward and reverse directions, as well as the centrifugal force during reverse rotation, shake off impurities or dirt attached to the impeller surface, thereby achieving self-cleaning of the drainage pump 20 and improving the cleaning efficiency of the drainage pump 20.

[0073] In the forward and reverse rotation cycle mode, it is necessary to consider the magnitude of the acceleration and the duration of rotation in each rotation in the cycle sequence.

[0074] In some embodiments of this application, the acceleration decreases sequentially, and the rotation time under each rotation is related to the current acceleration aref of the drainage pump 20, the first preset acceleration arefmin, and the preset time ts.

[0075] During the unblocking process, the degree of dirt and blockage should gradually decrease over time. Therefore, the acceleration should be reduced sequentially in the forward and reverse rotation cycle mode to ensure effective removal of dirt and blockage while reducing the power consumption of the drain pump 20.

[0076] In some embodiments of this application, the number of rotation cycles N in the forward and reverse rotation cycle mode is determined based on the ratio K of the maximum preset acceleration arefmax and the first preset acceleration arefmin of the drainage pump 20.

[0077] The larger K is, the greater the degree of clogging, and the greater the number of rotations N in the forward and reverse rotation cycle mode; conversely, the smaller K is, the greater the degree of clogging.

[0078] In some embodiments of this application, to ensure stable operation of the drainage pump 20, the acceleration between adjacent rotations has a fixed difference.

[0079] In some embodiments of this application, the fixed difference can be determined by the ratio of the difference between the maximum preset acceleration arefmax and the first preset acceleration arefmin to K, that is, the fixed difference Δa = (arefmax - arefmin) / K.

[0080] In some embodiments of this application, different drainage pumps 20 motors are given to illustrate the automatic unblocking process.

[0081] K is calculated based on the set maximum preset acceleration arefmax and the first preset acceleration arefmin.

[0082] In some embodiments of this application, if 1 < K ≤ 2, it indicates that the maximum and minimum acceleration values ​​that can clear the blockage are relatively close, suggesting that the degree of blockage in the drain pump 20 is relatively small. In this case, the number of rotations N in the forward and reverse cycle mode is relatively small. In this situation, the automatic blockage clearing process is described as follows.

[0083] The acceleration of the drainage pump 20 is switched to the maximum preset acceleration arefmax, and it starts to rotate in the positive direction. It maintains positive rotation for the rotation action time t=arefmin / aref*ts (at this time, the current acceleration aref is arefmax). Then it switches to reverse rotation and maintains negative rotation for the rotation action time t=ts-arefmin / aref*ts (at this time, the current acceleration aref is arefmax-△a).

[0084] Therefore, the rotation number in this forward and reverse cycle mode is two, that is, the cycle order is forward and reverse.

[0085] If the drain pump 20 is still blocked when the forward and reverse cycle is completed, it means that the drain pump 20 cannot achieve self-cleaning through one automatic unblocking process. At this time, an alarm can be set to warn the user to deal with the blockage fault in time.

[0086] In some embodiments of this application, see Figure 9 To ensure greater self-cleaning of the drain pump 20, a re-automatic cleaning process is also provided after the automatic unclogging process.

[0087] If the drain pump 20 is still blocked after the automatic unblocking process, it will enter the automatic unblocking process again.

[0088] The automatic deblocking process is similar to the automatic deblocking process described above, except that a second preset acceleration, arefmin, is set to be less than the first preset acceleration arefmin. 极限 Among them, the second preset acceleration isofmin 极限 This indicates the maximum acceleration at which the drainage pump 20 can operate normally during the unblocking process.

[0089] Before entering the automatic deblocking process, it will determine the maximum preset acceleration arefmax and the second preset acceleration arefmin based on the settings. 极限 The ratio of the two is used to calculate K'.

[0090] In some embodiments of this application, if 1 < K' ≤ 2, the automatic unblocking process is described as follows.

[0091] Switch the acceleration of drainage pump 20 to the maximum preset acceleration arefmax, and start rotating forward, with the rotation action time t=arefmin. 极限 The rotation remains forward for the duration of / aref*ts (at this point, the current acceleration aref is arefmax), then switches to counter-rotation and continues for the rotation duration t=ts-arefmin. 极限 The rotation remains in the opposite direction within / aref*ts (at this time, the current acceleration aref is arefmax-△a').

[0092] Where, △a' = (arefmax - arefmin) 极限 ) / K'.

[0093] At this point, the rotation number in the forward and reverse cycle mode during the automatic clearing process is still twice, that is, the cycle order is forward and reverse.

[0094] In some embodiments of this application, if 2 < K' ≤ 3, it indicates that the difference between the maximum and minimum acceleration values ​​that can clear the blockage is slightly large, suggesting that the blockage degree of the drain pump 20 is slightly greater. In this case, the number of rotations in the forward and reverse cycle mode increases as K' increases. The automatic blockage clearing process in this case is described as follows.

[0095] Switch the acceleration of drainage pump 20 to the maximum preset acceleration arefmax, and start rotating forward, with the rotation action time t=arefmin. 极限 The rotation remains forward for / aref*ts (at this point, the current acceleration aref is arefmax), then switches to counter-rotation and continues for the rotational duration t=2*arefmin. 极限The rotation remains in the reverse direction for the duration of / aref*ts (at this point, the current acceleration aref is arefmax - △a'), then switches to forward rotation and continues for the rotational duration t = ts - 2 * arefmin 极限 The system maintains positive rotation within / aref*ts (at this time, the current acceleration aref is arefmax-2△a').

[0096] Where, △a' = (arefmax - arefmin) 极限 ) / K'.

[0097] Therefore, the number of rotations in the forward and reverse cycle mode during the automatic clearing process is increased to three, that is, the cycle order is forward and reverse.

[0098] See Figure 10 After completing the forward and reverse cycle of the automatic unblocking process, if the drain pump 20 is still blocked, an alarm will be triggered to alert the user and prompt them to address the blockage fault promptly.

[0099] In some embodiments of this application, if 3 < K ≤ 4, it indicates that the gap between the maximum and minimum acceleration values ​​that can clear the blockage is large, suggesting a significant degree of blockage in the drain pump 20. In this case, the number of rotations in the forward and reverse cycle mode increases as K increases. The automatic blockage clearing process is described below.

[0100] The acceleration of the drainage pump 20 is switched to the maximum preset acceleration arefmax, and it starts to rotate forward. It maintains forward rotation for a rotation duration of t=arefmin / aref*ts (at this time, the current acceleration aref is arefmax). Then it switches to reverse rotation and maintains reverse rotation for a rotation duration of t=2*arefmin / aref*ts (at this time, the current acceleration aref is arefmax-Δa). Then it switches to forward rotation and maintains forward rotation for a rotation duration of t=3*arefmin / aref*ts (at this time, the current acceleration aref is arefmax-2*Δa). Then it switches to reverse rotation again and maintains reverse rotation for a rotation duration of t=ts-3*arefmin / aref*ts (at this time, the current acceleration aref is arefmax-3Δa).

[0101] Where, △a = (arefmax - arefmin) / K.

[0102] Therefore, the number of rotations in this forward and reverse cycle mode increases to four, that is, the cycle order is forward, reverse, and counter-reverse.

[0103] If the drain pump 20 is still blocked when the forward and reverse cycle is completed, it means that the drain pump 20 cannot achieve self-cleaning through one automatic unblocking process. At this time, an alarm can be set to warn the user to deal with the blockage fault in time.

[0104] In some embodiments of this application, in order to ensure greater self-cleaning of the drain pump 20, a second automatic cleaning process is performed after the automatic cleaning process, which can be described as follows.

[0105] Before entering the automatic deblocking process, it will determine the maximum preset acceleration arefmax and the second preset acceleration arefmin based on the settings. 极限 The ratio of the two is used to calculate K'.

[0106] In some embodiments of this application, if 3 < K' ≤ 4, the automatic unblocking process is described as follows.

[0107] Switch the acceleration of drainage pump 20 to the maximum preset acceleration arefmax, and start rotating forward, with the rotation action time t=arefmin. 极限 The rotation remains forward for / aref*ts (at this point, the current acceleration aref is arefmax), then switches to counter-rotation and continues for the rotational duration t=2*arefmin. 极限 The rotation remains in the reverse direction for the duration of / aref*ts (at this point, the current acceleration aref is arefmax - △a'), then switches to forward rotation and continues for the rotational duration t = 3*arefmin. 极限 The rotation remains forward for the duration of / aref*ts (at this point, the current acceleration aref is arefmax-2*△a'), then switches to reverse rotation and continues for the rotation duration t=ts-3*arefmin. 极限 The rotation remains in reverse within / aref*ts (at this time, the current acceleration aref is arefmax-3△a').

[0108] Where, △a' = (arefmax - arefmin) 极限 ) / K'.

[0109] Therefore, the rotation frequency in the forward and reverse cycle mode during the automatic clearing process is still four times.

[0110] In some embodiments of this application, if 4 < K' ≤ 5, it indicates a large difference between the maximum and minimum acceleration values ​​that can clear the blockage, suggesting a significant degree of blockage in the drain pump 20. In this case, the number of rotations in the forward and reverse cycle mode increases as K' increases. The automatic blockage clearing process in this situation is described below.

[0111] Switch the acceleration of drainage pump 20 to the maximum preset acceleration arefmax, and start rotating forward, with the rotation action time t=arefmin. 极限 The rotation remains forward for / aref*ts (at this point, the current acceleration aref is arefmax), then switches to counter-rotation and continues for the rotational duration t=2*arefmin. 极限 The rotation remains in the reverse direction for the duration of / aref*ts (at this point, the current acceleration aref is arefmax - △a'), then switches to forward rotation and continues for the rotational duration t = 3*arefmin. 极限 The rotation remains forward for / aref*ts (at this point, the current acceleration aref is arefmax-2△a'), then switches to counter-rotation and continues for the rotational duration t=4*arefmin. 极限 The rotation remains in the reverse direction for the duration of / aref*ts (at this point, the current acceleration aref is arefmax-3△a'), and then switches to forward rotation for the duration t=ts-4*arefmin. 极限 The system maintains forward and reverse rotation within / aref*ts (at this time, the current acceleration aref is arefmax-4△a').

[0112] Where, △a' = (arefmax - arefmin) 极限 ) / K'.

[0113] Therefore, the number of rotations in the forward and reverse cycle mode during the automatic clearing process is increased to five times, that is, the cycle order is forward-reverse-reverse-reverse.

[0114] As described above, depending on the degree of clogging of the drain pump 20, there will be different K values. For different K values, there will be different rotation cycles, and the acceleration of each rotation (e.g., forward and reverse rotation) will be different. Furthermore, the rotation duration of each rotation will also be different due to its relationship with the acceleration. Therefore, the load torque of the drain pump 20 motor will be changed during each rotation, thereby adaptively adjusting the load torque of the drain pump 20 according to the degree of clogging to clear the clogging from the drain pump 20.

[0115] In some embodiments of this application, a larger acceleration is controlled for the drain pump 20 in the initial stage of unclogging to ensure a larger unclogging capacity of the drain pump 20. As the unclogging time progresses, the acceleration is gradually reduced to ensure that the dirt and blockage are removed while reducing power consumption.

[0116] In some embodiments of this application, since the first preset acceleration arefmin is the minimum acceleration set by the motor of the drain pump 20 to clear the blockage, see [reference needed]. Figure 8Before the automatic unblocking process begins, if the drain pump 20 is initially determined to be blocked, the acceleration of the drain pump 20 can be switched to the first preset acceleration arefmin. In this way, both unblocking and energy saving of the drain pump 20 are taken into account.

[0117] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0118] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A motor control device, characterized in that, include: The frequency converter topology circuit is used to invert the DC power supply from the bus to a three-phase voltage to power the drainage pump motor. A drive controller is configured to drive and control the variable frequency topology circuit, and to initiate an automatic unblocking process when the drainage pump stalls and remains stalled for a preset time. The automatic unblocking process includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation action time under each rotation is related to the current acceleration of the drainage pump, the first preset acceleration, and the preset time. Wherein, the maximum preset acceleration is the maximum acceleration value that can clear the blockage, and the first preset acceleration is the minimum acceleration value that can clear the blockage.

2. The motor control device according to claim 1, characterized in that, The maximum preset acceleration and the first preset acceleration are set according to different drainage pump motors; The larger the ratio K of the maximum preset acceleration to the first preset acceleration, the more rotational cycles there are in each rotation in the cyclic sequence.

3. The motor control device according to claim 2, characterized in that, The acceleration between adjacent rotations of the drainage pump in the cycle sequence differs by a fixed value. Wherein, the fixed difference is the ratio of the difference between the maximum preset acceleration and the first preset acceleration to K.

4. The motor control device according to claim 1, characterized in that, The automatic unblocking process also includes: The step of checking whether the drainage pump is blocked after the automatic unblocking process is completed; If the drain pump is still blocked, a re-automatic unblocking process can be initiated, which includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation duration of each rotation is related to the current acceleration of the drainage pump, the second preset acceleration, and the preset time. Wherein, the second preset acceleration is the acceleration of the first preset acceleration; If the drain pump remains blocked after the automatic unblocking process is completed, an alarm will be triggered.

5. The motor control device according to claim 4, characterized in that, The maximum preset acceleration, the first preset acceleration, and the second preset acceleration are preset according to different drainage pump motors; During the automatic unblocking process, the larger the ratio K of the maximum preset acceleration to the first preset acceleration, the more rotations there are in the cycle sequence during the automatic unblocking process. During the automatic deblocking process, the larger the ratio K' of the maximum preset acceleration to the second preset acceleration, the more rotations there are in the cycle sequence during the automatic deblocking process.

6. The motor control device according to claim 4, characterized in that, During the automatic unblocking process, the acceleration difference between adjacent rotations of the drainage pump in the cycle sequence is a first fixed difference, which is the ratio of the difference between the maximum preset acceleration and the first preset acceleration to K. During the automatic unblocking process, the acceleration difference between adjacent rotations of the drain pump in the cycle sequence is a second fixed difference, which is the ratio of the difference between the maximum preset acceleration and the second preset acceleration to K'.

7. The motor control device according to claim 1, characterized in that, When the drain pump is initially determined to be stuck before entering the automatic unblocking process, the acceleration of the drain pump is switched to the first preset acceleration.

8. The motor control device according to claim 1, characterized in that, The motor control device further includes: A current detection unit is used to detect the motor current of the drainage pump; When the speed of the drainage pump does not reach the specified speed and / or the motor current reaches the upper limit of the specified current value, the drive controller determines that the drainage pump is stalled.

9. An air conditioner, characterized in that, include: The refrigerant circulation loop allows the refrigerant to circulate within a loop consisting of the compressor, condenser, expansion valve, and evaporator. A drip tray, used to collect condensate produced when the air conditioner is in cooling operation; A drain pump, installed inside the water receiving pan, is used to drain the condensate in the water receiving pan to the outside; The frequency converter topology circuit is used to invert the DC power supply from the bus to a three-phase voltage to power the drainage pump motor. A drive controller is configured to drive and control the variable frequency topology circuit, and to initiate an automatic unblocking process when the drainage pump stalls and remains stalled for a preset time. The automatic unblocking process includes the following: Switch the acceleration of the drainage pump to the maximum preset acceleration, and control the drainage pump to enter the forward and reverse rotation cycle mode; In the forward and reverse rotation cycle mode, the acceleration of each rotation of the drainage pump in the cycle sequence decreases sequentially, and the rotation action time under each rotation is related to the current acceleration of the drainage pump, the first preset acceleration, and the preset time. Wherein, the maximum preset acceleration is the maximum acceleration value that can clear the blockage, and the first preset acceleration is the minimum acceleration value that can clear the blockage.

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