Water pump unit and heating control device

Abstract

The utility model relates to a water pump unit and a heating control device.The water pump unit comprises a control cabinet, a frequency converter, a water pump motor, the heating control device and a motor temperature sensor, the first input end of the heating control device is connected with the motor temperature sensor, and the motor temperature sensor is arranged in the water pump motor; the motor temperature sensor is used for detecting the motor temperature in the motor; the first output end of the heating control device is connected with the water pump motor through the frequency converter, the heating control device and the frequency converter are arranged in the control cabinet, and the heating control device is used for controlling the frequency converter to only output exciting current according to the temperature of the motor, so that the water pump motor emits heat during shutdown to eliminate condensation in the motor. By implementing the water pump unit provided by the invention, the condensation in the motor can be eliminated at low cost when the water pump motor is shut down.

Description

Technical Field

[0001] This application relates to the technical field of water pumps, and particularly to a water pump unit and a heating control device. Background Art

[0002] A water pump unit is a water supply, drainage and circulating water pump system that combines a water pump and a water pump motor. It is widely used in industries, agriculture, construction and other fields, providing important support for the transportation and pressurization of liquids.

[0003] Due to changes in environmental temperature and humidity, especially in a humid environment, condensation may occur inside and outside the equipment. In particular, the water pump motor and control drive system in the water pump unit have a complex structure and contain a variety of precision electronic components. Once condensation occurs, it will cause damage to electronic components, rusting of parts, short circuits of motors or electrical components, rendering the equipment ineffective, and even causing personal injury.

[0004] However, there is generally no special condensation removal solution designed specifically for water pump motors at present. Because it is usually considered that the water pump motor will generate heat during operation, so there is no condensation problem. However, it is not noticed that if the water pump unit does not work for a long time in a humid environment, it is very likely to generate condensation. Utility Model Content

[0005] Based on this, a water pump unit is provided, which can eliminate the condensation inside the motor at low cost when the water pump motor stops, and improve the condensation problem of the water pump motor in the stopped state in the prior art.

[0006] In a first aspect, this application provides a water pump motor, including a control cabinet, a frequency converter, a water pump motor, a heating control device and a motor temperature sensor; a first input end of the heating control device is connected to the motor temperature sensor, wherein the motor temperature sensor is arranged inside the water pump motor, and the motor temperature sensor is used to detect the motor temperature inside the motor; a first output end of the heating control device is connected to the water pump motor through the frequency converter, wherein the heating control device and the frequency converter are arranged inside the control cabinet, and the heating control device is used to control the frequency converter to only output exciting current according to the motor temperature, so that the water pump motor generates heat when it stops, in order to eliminate the condensation inside the motor.

[0007] Combined with the first aspect, in a first implementation manner of the first aspect, the water pump unit further includes an environmental temperature and humidity sensor, and the environmental temperature and humidity sensor is arranged outside the control cabinet and the water pump motor; a second input end of the heating control device is connected to the environmental temperature and humidity sensor, wherein the environmental temperature and humidity sensor is used to detect the environmental temperature and humidity, and the heating control device is used to detect whether condensation may occur inside the motor according to the environmental temperature and humidity and the motor temperature.

[0008] Combined with the first implementation manner of the first aspect, in the second implementation manner of the first aspect, the water pump unit further includes a cabinet temperature sensor and a heater; the third input end of the heating control device is connected to the cabinet temperature sensor, wherein the cabinet temperature sensor is arranged in the control cabinet, and the cabinet temperature sensor is used to detect the temperature inside the control cabinet. The heating control device is used to detect whether condensation may occur inside the control cabinet according to the ambient temperature and humidity and the temperature inside the cabinet; the second output end of the heating control device is connected to the heater, wherein the heater is arranged in the control cabinet, and the heater is used to heat the control cabinet to eliminate the condensation inside the cabinet when condensation occurs inside the control cabinet. The heating control device is further used to control the heater to heat the control cabinet to eliminate the condensation inside the cabinet.

[0009] Combined with the first aspect, in the third implementation manner of the first aspect, the water pump unit includes a plurality of frequency converters and a plurality of water pump motors. The heating control device includes a plurality of first output ends and a plurality of first input ends. The number of water pump motors, frequency converters, first output ends, and first input ends is the same. Among them: each first output end of the heating control device is respectively connected to the corresponding frequency converter in a one-to-one manner, each frequency converter is respectively connected to the corresponding water pump motor in a one-to-one manner, and each first input end of the heating control device is respectively connected to the motor temperature sensor in the corresponding water pump motor in a one-to-one manner.

[0010] Combined with the first aspect, in the fourth implementation manner of the first aspect, the cabinet temperature sensor is arranged at the ventilation and filtration window of the control cabinet, and the ventilation and filtration window is located above the side wall of the control cabinet.

[0011] Combined with the first aspect or the fourth implementation manner of the first aspect, in the fifth implementation manner of the first aspect, the heater is arranged below the side wall of the control cabinet.

[0012] Combined with the first aspect, in the sixth implementation manner of the first aspect, the water pump unit further includes a shutdown heating switch. The heating control device is connected to the frequency converter through the shutdown heating switch. Among them, when the shutdown heating switch is closed, the heating control device is connected to the frequency converter, and the water pump motor switches from the normal working state to the shutdown heating state.

[0013] In the second aspect, a heating control device is provided. The heating control device is applied to the water pump unit in any one of the first aspect to the first aspect. Among them: the first input end of the heating control device is connected to the motor temperature sensor; the first output end of the heating control device is connected to the water pump motor through the frequency converter. Among them, the heating control device and the frequency converter are arranged inside the control cabinet. The heating control device is used to control the frequency converter to only output exciting current according to the motor temperature, so that the water pump motor generates heat when it stops, so as to eliminate the condensation inside the motor.

[0014] Combined with the second aspect, in the first implementation manner of the second aspect, the heating control device includes a dew point calculator, a comparator, and a PID controller; the input end of the dew point calculator is connected to the ambient temperature and humidity sensor, and the output end of the dew point calculator is connected to the comparator. Among them, the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity; the first input end of the comparator is connected to the dew point calculator, the second input end of the comparator is connected to the motor temperature sensor, and the output end of the comparator is connected to the PID controller. Among them, the comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature; the first input end of the PID controller is connected to the comparator, the second input end of the PID controller is connected to the motor temperature sensor, and the output end of the PID controller is connected to the frequency converter. Among them, the PID controller is used to adjust the magnitude of the excitation current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor.

[0015] Combined with the second aspect, in the second implementation manner of the second aspect, the heating control device includes a dew point calculator, a first comparator, a second comparator, and a PID controller; the input end of the dew point calculator is connected to the ambient temperature and humidity sensor, the first output end of the dew point calculator is connected to the first comparator, and the second output end of the dew point calculator is connected to the second comparator. Among them, the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity; the first input end of the first comparator is connected to the dew point calculator, the second input end of the first comparator is connected to the motor temperature sensor, and the output end of the first comparator is connected to the PID controller. Among them, the first comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature; the first input end of the second comparator is connected to the dew point calculator, the second input end of the second comparator is connected to the cabinet temperature sensor, and the output end of the second comparator is connected to the heater. Among them, the second comparator is used to detect whether condensation may occur inside the control cabinet according to the dew point temperature and the cabinet temperature; the first input end of the PID controller is connected to the first comparator, the second input end of the PID controller is connected to the motor temperature sensor, and the output end of the PID controller is connected to the frequency converter. Among them, the PID controller is used to adjust the magnitude of the excitation current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor.

[0016] In summary, the present application provides a water pump unit and a heating control device. A heating control device and a motor temperature sensor are added to the water pump unit. The motor temperature sensor is arranged inside the motor, the first input end of the heating control device is connected to the motor temperature sensor, and the first output end of the heating control device is connected to the water pump motor through a frequency converter. So that the heating control device can control the frequency converter to output only the exciting current, thereby controlling the water pump motor to generate heat when it stops, to eliminate the condensation inside the motor. And because the heating control device adjusts the exciting current in real time according to the motor temperature, it can prevent the motor temperature from being too high or too low. While eliminating the condensation inside the motor, it protects the motor from being burned out and reduces energy consumption. In addition, since the frequency converter is an existing device in the water pump unit, there is no need to wind a large number of heating tapes around the water pump motor. Therefore, the present application also has the advantages of being easy to implement and low cost. Generally speaking, the present application can eliminate the condensation inside the motor at low cost when the water pump motor stops. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of a water pump unit in an embodiment;

[0018] Figure 2 is a schematic structural diagram of a water pump unit in another embodiment;

[0019] Figure 3 is a schematic structural diagram of a water pump unit in another embodiment;

[0020] Figure 4 is a schematic structural diagram of a water pump unit in another embodiment;

[0021] Figure 5 is a schematic structural diagram of a water pump unit in another embodiment;

[0022] Figure 6 is a schematic structural diagram of a water pump unit in another embodiment;

[0023] Figure 7 is a schematic structural diagram of a water pump unit in another embodiment.

[0024] The reference numerals in the drawings are as follows:

[0025] Control cabinet 110, frequency converter 120, first frequency converter 121, second frequency converter 122, third frequency converter 123, water pump motor 130, first water pump motor 131, second water pump motor 132, third water pump motor 133, heating control device 140, dew point calculator 141, comparator 142, PID controller 143, first comparator 144, second comparator 145, motor temperature sensor 150, ambient temperature and humidity sensor 160, cabinet internal temperature sensor 170, heater 180, shutdown heating switch 190, first input terminal 10 of the heating control device, first eleventh input terminal to first thirteenth input terminals 11 - 13 of the heating control device, first output terminal 20 of the heating control device, first eleventh output terminal to first thirteenth output terminals 21 - 23 of the heating control device, second input terminal 30 of the heating control device, third input terminal 40 of the heating control device, second output terminal 50 of the heating control device. Detailed implementation mode

[0026] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0027] It should be noted that the drawings provided in this embodiment only illustrate the basic concept of the present utility model in a schematic manner. Therefore, only the components related to the present utility model are shown in the drawings, rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0028] The structures, proportions, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the limiting conditions under which the present utility model can be implemented. Therefore, they do not have technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present utility model can produce and the objectives that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in the present utility model.

[0029] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "middle", "longitudinal", "transverse", "horizontal", "inner", "outer", "radial", "circumferential", etc. cited in this specification is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of simplified description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0030] Currently, there is still a lack of a solution specifically for eliminating the condensation inside the motor when the water pump motor stops. In this regard, in order to effectively eliminate the condensation inside the water pump motor, a large number of heating tapes can be wound around the water pump unit. However, this method has high costs and is difficult to implement because there may be multiple water pump motors in the water pump unit, and each motor requires a large number of heating tapes, resulting in extremely high costs. Moreover, the internal structure of the water pump motor is complex and compact. Winding heating tapes inside the water pump motor will affect the original structure layout. If the heating tapes cannot be reasonably arranged, it may even reduce the working efficiency of the motor.

[0031] In order to solve the condensation problem of the water pump motor at low cost when it stops, the present application proposes a water pump unit, which not only solves the condensation problem of the water pump motor when it stops, but also has the advantages of low cost and easy implementation compared with the solution of directly winding heating tapes inside the motor.

[0032] Specifically, as Figure 1 shown, it is an embodiment of the water pump unit provided by the present application. The water pump unit includes a control cabinet 110, an inverter 120, a water pump motor 130, a heating control device 140, and a motor temperature sensor 150; the heating control device 140 includes a first input terminal 10 and a first output terminal 20. The first input terminal 10 of the heating control device 140 is connected to the output terminal of the motor temperature sensor 150, and the first output terminal 20 of the heating control device 140 is connected to the water pump motor 130 through the inverter 120.

[0033] Among them, the motor temperature sensor 150 is arranged inside the water pump motor 130. The motor temperature sensor 150 is used to detect the motor temperature inside the motor. The heating control device 140 and the inverter 120 are arranged inside the control cabinet 110. The heating control device 140 is used to control the inverter 120 to only output excitation current according to the motor temperature, so that the water pump motor 130 is heated when it stops to eliminate the condensation inside the motor.

[0034] It should be noted that in the water pump unit, the water pump motor is used to drive the water pump to work, and the inverter is usually used to control the start, stop, and speed of the water pump motor, etc. The current output by the inverter to the water pump motor mainly includes two types: excitation current and torque current. The excitation current is used to generate or maintain the magnetic field of the water pump motor, while the torque current is used to generate a rotational torque to drive the water pump motor to rotate. By adjusting the magnitude and direction of these two currents, the inverter can achieve precise control of the motor speed, output torque, and operating efficiency. When the water pump motor is in the working state, the inverter needs to output both the excitation current and the torque current at the same time. The excitation current and the torque current exist simultaneously and cooperate with each other to jointly achieve the control of the motor. When the water pump motor stops, the inverter does not output current.

[0035] In the water pump unit provided by the present application, when the water pump motor stops, the frequency converter is used to output only the exciting current to the water pump motor to eliminate the condensation inside the motor. In order to eliminate the condensation inside the motor when the water pump motor stops, a heating control device and a motor temperature sensor are added to the water pump unit in the present application. On the one hand, the first output end of the heating control device is connected to the frequency converter, so that the heating control device can control the frequency converter to output only the exciting current. On the other hand, the motor temperature sensor is arranged in the water pump motor, and the first input end of the heating control device is connected to the motor temperature sensor, so that the heating control device can monitor the motor temperature in real time and control the magnitude of the exciting current output by the frequency converter according to the motor temperature in real time, preventing the exciting current from being too small or too large. If the exciting current is too small, the condensation inside the motor cannot be eliminated; if the exciting current is too large, the temperature inside the motor will soar, burning out the circuits and electronic components inside the motor. Therefore, in the present application, by adding a heating control device and a motor temperature sensor to the water pump motor, connecting the first input end of the heating control device to the motor temperature sensor, and connecting the first output end of the heating control device to the water pump motor through the frequency converter, the condensation inside the motor is eliminated when the water pump motor stops, and the electronic components inside the water pump motor are protected.

[0036] It should also be noted that compared with the method of winding a heating tape inside the water pump motor, the water pump unit provided by the present application has the advantages of low cost and easy implementation. Because the heating control device can be a PID controller, the temperature sensor can be a thermistor, and the controller can be integrated inside the control system of the unit without additional cost. The temperature sensor has a low cost and a small volume, and is easy to be arranged inside the water pump motor without changing the internal structure of the water pump motor. Winding a heating tape inside the water pump motor requires changing the internal structure of the water pump motor, adding additional control elements, and requires long-term heating when the motor is not started, resulting in serious energy waste. Therefore, the method of using a heating tape is not the optimal solution.

[0037] In summary, in the present application, by adding a heating control device and a motor temperature sensor to the water pump motor, connecting the first input end of the heating control device to the motor temperature sensor, and connecting the first output end of the heating control device to the water pump motor through the frequency converter, the condensation inside the motor can be eliminated at low cost when the water pump motor stops, and the electronic components inside the water pump motor are protected.

[0038] In another implementable embodiment, in order to better eliminate the condensation inside the motor, on the basis of the water pump unit as shown in Figure 1 the present embodiment also adds an environmental temperature and humidity sensor, as shown in Figure 2As shown, specifically, the water pump unit further includes an environmental temperature and humidity sensor 160, and the heating control device 140 further includes a second input terminal; the environmental temperature and humidity sensor 160 is disposed outside the control cabinet 110 and the water pump motor 130, and the second input terminal 30 of the heating control device 140 is connected to the environmental temperature and humidity sensor 160.

[0039] Among them, the environmental temperature and humidity sensor 160 is used to detect the environmental temperature and humidity, and the environmental temperature and humidity include the environmental temperature T0 and the environmental humidity RH. The heating control device 140 is used to detect whether condensation may occur inside the motor according to the environmental temperature and humidity and the motor temperature. Specifically, on the one hand, the heating control device 140 is used to calculate the dew point temperature T1 according to the environmental temperature and humidity, and calculate the dew point temperature T1 at the current environmental temperature and humidity using the Magnus-Tetens formula. The dew point temperature T1 is the critical temperature for condensation to occur inside the water pump motor 130. On the other hand, the heating control device 140 is further used to detect whether condensation may occur inside the motor according to the dew point temperature T1 and the motor temperature T2. For example, when T2 ≤ T1, the heating control device 140 detects that condensation has occurred or is about to occur inside the water pump motor 130. Conversely, when T2 > T1, no condensation has occurred inside the water pump motor 130 and no condensation is about to occur.

[0040] It should be noted that in this application, by disposing the environmental temperature and humidity sensor outside the control cabinet and the water pump motor, the environmental temperature and humidity can be detected more accurately. And by connecting the second input terminal of the heating control device to the environmental temperature and humidity sensor, the heating control device can detect in real time whether condensation may occur inside the motor, so as to better control the start and stop of the frequency converter, thereby eliminating condensation inside the motor.

[0041] In another implementable manner, in the water pump unit, in addition to the water pump motor, the frequency converter and the heating control device may also have short-circuit faults due to condensation. Therefore, in order to more comprehensively eliminate condensation in the water pump unit, in this embodiment, on the basis of the water pump unit as shown in Figure 2 a cabinet temperature sensor and a heater are additionally provided in the control cabinet, as shown in Figure 3 Specifically, the water pump unit further includes a cabinet temperature sensor 170 and a heater 180, and the heating control device 140 further includes a third input terminal 40 and a second output terminal 50; the third input terminal 40 of the heating control device 140 is connected to the cabinet temperature sensor 170, and the second output terminal 50 of the heating control device 140 is connected to the heater 180.

[0042] Among them, the in-cabinet temperature sensor 170 and the heater 180 are arranged in the control cabinet 110. The in-cabinet temperature sensor 170 is used to detect the in-cabinet temperature T3 of the control cabinet 110, and the heater 180 is used to heat the control cabinet 110 to eliminate the in-cabinet condensation when there is condensation in the control cabinet 110. The heating control device 140 is used to detect the internal condensation of the control cabinet 110 according to the ambient temperature and humidity and the in-cabinet temperature T3. For example, when T3 ≤ T1, the heating control device 140 detects that condensation has occurred or is about to occur inside the water pump motor 130. On the contrary, when T3 > T1, there is no condensation inside the water pump motor 130 and no condensation is about to occur; the heating control device 140 is also used to control the heater 180 to heat the control cabinet 110 when there is condensation or about to occur condensation in the control cabinet 110 to eliminate the in-cabinet condensation.

[0043] Further, in order to improve the accuracy of in-cabinet temperature detection, the in-cabinet temperature sensor is arranged at the ventilation and filtration window of the control cabinet. The ventilation and filtration window is located above the side wall of the control cabinet to improve the problem of inaccurate in-cabinet temperature detection caused by uneven heat distribution.

[0044] Furthermore, in order to better heat the entire control cabinet, the heater is arranged below the side wall of the control cabinet to improve the problem of poor condensation elimination effect caused by uneven heat transfer. Since hot air has a lower density than cold air, hot air will conduct upward. Arranging the heater below the side wall of the control cabinet can heat the entire cabinet more evenly. However, if it is arranged above the control cabinet, it may not be able to heat the lower part of the control cabinet well, resulting in the inability to eliminate the condensation inside the cabinet below. In addition, when the in-cabinet temperature sensor is arranged at the ventilation and filtration window above the control cabinet and the heater is arranged below the control cabinet in this application, the in-cabinet temperature sensor and the heater are far away from each other, which can improve the problem of inaccurate in-cabinet temperature detection caused by the temperature sensor being too close to the heat source.

[0045] In another implementable manner, in the water pump unit, there may be multiple water pump motors and multiple frequency converters. For this case, this embodiment provides an independent control structure. By setting multiple first output terminals and multiple first input terminals on the heating control device, connecting each first input terminal to the motor temperature controller in the corresponding water pump motor respectively, and connecting each first output terminal to the corresponding frequency converter respectively, the excitation current output by the corresponding water pump motor can be controlled respectively, so as to independently eliminate the condensation inside each motor, which has stronger flexibility and controllability. Specifically, the water pump unit includes multiple frequency converters and multiple water pump motors, the heating control device includes multiple first output terminals and multiple first input terminals, and the number of water pump motors, frequency converters, first output terminals, and first input terminals is the same.

[0046] Among them, each first output terminal of the heating control device is respectively connected to a corresponding frequency converter in a one-to-one manner, each frequency converter is respectively connected to a corresponding water pump motor in a one-to-one manner, and each first input terminal of the heating control device is respectively connected to a motor temperature sensor in a corresponding water pump motor in a one-to-one manner.

[0047] For example, based on the water pump unit as Figure 3 shown, the present application provides a specific embodiment. As Figure 4 shown, the water pump unit includes three frequency converters: a first frequency converter 121, a second frequency converter 122, and a third frequency converter 123; the water pump unit further includes three water pump motors: a first water pump motor 131, a second water pump motor 132, and a third water pump motor 133; the heating control device includes three first input terminals: a first first input terminal 11, a first second input terminal 12, and a first third input terminal 13; the heating control device includes three first output terminals: a first first output terminal 21, a first second output terminal 22, and a first third output terminal 23. It should be noted that, for the sake of simplifying the illustration, the motor temperature sensor 150 is omitted in the figure, and the motor temperature sensor 150 is respectively provided inside each water pump motor 130 in each figure, which will not be elaborated hereinafter. Moreover Figure 4 the number of the frequency converters, water pump motors, first input terminals, and first output terminals in

[0048] is only an example for better understanding this embodiment, and the specific number is not limited to three.

[0049] In another implementable embodiment, in order to ensure that the heating control device can only perform heating control on the water pump motor when the water pump motor is in the shutdown state, a shutdown heating switch is further provided in the water pump unit. The shutdown heating switch is arranged in the connection line between the heating control device and the frequency converter. Specifically, the water pump unit further includes a shutdown heating switch 190, and the heating control device 140 is connected to the frequency converter 120 through the shutdown heating switch 190. Among them, when the shutdown heating switch 190 is closed, the heating control device 140 is connected to the frequency converter 120, and the water pump motor 130 switches from the normal working state to the shutdown heating state.

[0050] Furthermore, in the case of multiple water pump motors in the water pump unit, since not all water pump motors in the water pump unit will work simultaneously, some water pump motors may be in the shutdown state. Therefore, condensation may occur in these shutdown water pump motors. For this reason, the present application also provides another implementable embodiment. In this embodiment, the water pump unit further includes multiple shutdown heating switches, and the number of shutdown heating switches is the same as the number of water pump motors, frequency converters, the first output terminal of the heating control device, and the first input terminal of the heating control device. Each shutdown heating switch is respectively used to connect between the corresponding first output terminal of the heating control device and the frequency converter. Among them, when any one of the shutdown heating switches is closed, the corresponding water pump motor switches from the normal working state to the shutdown heating state.

[0051] For example, based on the water pump unit as shown in Figure 4 the present application provides a specific example. As shown in Figure 5 the water pump unit includes three shutdown heating switches 190: the first shutdown heating switch 191, the second shutdown heating switch 192, and the third shutdown heating switch 193; the first output terminal 21 of the heating control device 140 is connected to the first frequency converter 121 through the first shutdown heating switch 191, the second output terminal 22 of the heating control device 140 is connected to the second frequency converter 122 through the second shutdown heating switch 192, and the third output terminal 23 of the heating control device 140 is connected to the third frequency converter 123 through the third shutdown heating switch 193;

[0052] When the first shutdown heating switch 191 is closed, the first output terminal 21 of the heating control device 140 controls the frequency converter 121 to output only the exciting current to the first water pump motor 131 to heat the first water pump motor 131, so that the first water pump motor 131 switches from the normal working state to the shutdown heating state; when the second shutdown heating switch 192 is closed, the second output terminal 22 of the heating control device 140 controls the frequency converter 122 to output only the exciting current to the second water pump motor 132 to heat the second water pump motor 132, so that the second water pump motor 132 switches from the normal working state to the shutdown heating state; when the third shutdown heating switch 193 is closed, the third output terminal 23 of the heating control device 140 controls the frequency converter 123 to output only the exciting current to the third water pump motor 133 to heat the third water pump motor 133, so that the third water pump motor 133 switches from the normal working state to the shutdown heating state. It should be noted that Figure 5 The numbers of the shutdown heating switches, frequency converters, water pump motors, first input terminals and first output terminals in

[0053] are only examples for better understanding of this embodiment, and the specific numbers are not limited to three.

[0054] In addition, the present application also provides a heating control device, which is applied to any of the water pump units as described above, wherein: the first input terminal of the heating control device is connected to the motor temperature sensor; the first output terminal of the heating control device is connected to the water pump motor through the frequency converter, wherein the heating control device and the frequency converter are arranged inside the control cabinet, and the heating control device is used to control the frequency converter to output only the exciting current according to the motor temperature, so that the water pump motor generates heat when shutdown to eliminate the condensation inside the motor.

[0055] In another implementable manner, the present application also provides a specific embodiment of a heating control device. The heating control device includes a dew point calculator, a comparator, and a PID controller. The dew point calculator 141 includes an input end and an output end. The comparator includes a first input end, a second input end, and an output end. The PID controller includes a first input end, a second input end, and an output end. The input end of the dew point calculator is connected to the output end of the ambient temperature and humidity sensor. The output end of the dew point calculator is connected to the first input end of the comparator. The second input end of the comparator is connected to the motor temperature sensor. The output end of the comparator is connected to the first input end of the PID controller. The second input end of the PID controller is connected to the output end of the motor temperature sensor. The output end of the PID controller is connected to the input end of the frequency converter.

[0056] Among them, the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity. Specifically, the dew point calculator uses the Magnus-Tetens formula to calculate the dew point temperature T according to the ambient temperature and humidity, and considers the system error and control scheme degree to optimize the dew point temperature. Calculate T1 = T - threshold, and use T1 as the dew point temperature. The threshold is used to adjust the calculation error.

[0057] The comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature. Specifically, the comparator is used to compare the dew point temperature T1 with the motor temperature T2. When T2 ≤ T1, the comparator determines that condensation has occurred or is about to occur inside the water pump motor. Conversely, when T2 > T1, there is no condensation inside the water pump motor and no condensation is about to occur.

[0058] The PID controller is used to adjust the magnitude of the exciting current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor. Specifically, the PID controller aims to make the motor temperature T1 equal to the dew point temperature T2, and adjusts the magnitude of the level output to the frequency converter according to the monitored motor temperature, so that the frequency converter adjusts the magnitude of the exciting current output according to the real-time changing level magnitude. For example, when T2 > T1, the PID controller controls the frequency converter to reduce the magnitude of the exciting current to lower the motor temperature T2, achieving energy saving while protecting the motor from being burned out. When T2 < T1, the PID controller controls the frequency converter to increase the magnitude of the exciting current to raise the motor temperature T2 and eliminate condensation inside the motor.

[0059] For example, in combination with a water pump unit, based on the water pump unit as shown in Figure 2 the present application provides a specific example of a heating control device, as shown in Figure 6As shown, the heating control device 140 includes a dew point calculator 141, a comparator 142, and a PID controller 143. The input end In of the dew point calculator 141 is connected to the output end of the ambient temperature and humidity sensor 160. The output end Out of the dew point calculator 141 is connected to the first input end In1 of the comparator 142. The second input end In2 of the comparator 142 is connected to the output end of the motor temperature sensor in the water pump motor. The output end Out of the comparator 142 is connected to the first input end In1 of the PID controller 143. The second input end In2 of the PID controller 143 is connected to the output end of the motor temperature sensor 150. The output end of the PID controller 143 is connected to the frequency converter.

[0060] Among them, the dew point calculator 141 receives the ambient temperature and humidity sent by the output end of the ambient temperature and humidity sensor 160 through the input end In of the dew point calculator 141. The dew point calculator 141 is used to calculate the dew point temperature T1 according to the ambient temperature and humidity, and send the dew point temperature T1 to the first input end In1 of the comparator 142 through the output end Out of the dew point calculator 141.

[0061] The comparator 142 receives the dew point temperature T1 sent by the output end Out of the dew point calculator 141 through the first input end In1 of the comparator 142, and receives the motor temperature T2 sent by the output end of the motor temperature sensor 150 of the water pump motor 130 through the second input end In2 of the comparator 142. The comparator 142 is used to detect whether condensation may occur inside the motor according to the dew point temperature T1 and the motor temperature T2, and send the dew point temperature T1 to the first input end In1 of the PID controller 143 through the output end Out of the comparator 142 when condensation has occurred or is about to occur inside the motor.

[0062] The PID controller 143 receives the dew point temperature T1 sent by the output end Out of the comparator 142 through the first input end In1 of the PID controller 143, and receives the motor temperature T2 sent by the output end of the motor temperature sensor of the water pump motor through the second input end In2 of the PID controller 143. The PID controller 143 is used to send a control signal to the input end of the frequency converter through the output end Out of the PID controller 143.

[0063] It should be noted that in Figure 6In the example, the water pump unit has multiple frequency converters and water pump motors. When the output end of the PID controller 143 is connected to the frequency converters, it is connected to each frequency converter 120 through different output ends. Similarly, the PID controller 143 is connected to the motor temperature sensors in the water pump motors 130 through different second input ends, and the comparator 142 is connected to the motor temperature sensors in the water pump motors 130 through different second input ends. Specifically, the output end of the PID controller 143 includes a first output end, a second output end, and a third output end. The first output end, the second output end, and the third output end of the PID controller 143 are respectively connected to the first frequency converter 121, the second frequency converter 122, and the third frequency converter 123. The second input end In2 of the PID controller 143 includes a first second input end, a second second input end, and a third second input end. The first second input end, the second second input end, and the third second input end of the PID controller 143 are respectively connected to the motor temperature sensors in the first water pump motor 131, the second water pump motor 132, and the third water pump motor 133. The second input end In2 of the comparator 142 includes a first second input end, a second second input end, and a third second input end. The first second input end, the second second input end, and the third second input end of the comparator 142 are respectively connected to the motor temperature sensors in the first water pump motor 131, the second water pump motor 132, and the third water pump motor 133.

[0064] It should also be noted that in Figure 6 the example, a shutdown heating switch 190 is additionally provided in the water pump unit. The shutdown heating switch 190 is arranged on the connection line between the output end of the PID controller 143 and the input end of the frequency converter. When the shutdown heating switch 190 is closed, the heating control device 140 is connected to the frequency converter, and the heating control device 140 can control the frequency converter to output only the excitation current to the water pump motor, so that the water pump motor switches from the normal working state to the shutdown heating state. When multiple frequency converters are provided in the water pump unit, the same number of shutdown heating switches as the number of frequency converters are provided. In this example, the shutdown heating switch 190 includes a first shutdown heating switch 191, a second shutdown heating switch 192, and a third shutdown heating switch 193. The first shutdown heating switch 191 is connected between the first output end of the PID controller 143 and the first frequency converter 121, the second shutdown heating switch 192 is connected between the second output end of the PID controller 143 and the second frequency converter 122, and the third shutdown heating switch 193 is connected between the third output end of the PID controller 143 and the third frequency converter 123.

[0065] In another possible implementation, the present application also provides a specific embodiment of a heating control device. The heating control device includes a dew point calculator, a first comparator, a second comparator, and a PID controller. The input end of the dew point calculator is connected to an ambient temperature and humidity sensor. The first output end of the dew point calculator is connected to the first comparator, and the second output end of the dew point calculator is connected to the second comparator. Among them, the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity. The first input end of the first comparator is connected to the dew point calculator, the second input end of the first comparator is connected to a motor temperature sensor, and the output end of the first comparator is connected to the PID controller. Among them, the first comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature. The first input end of the second comparator is connected to the dew point calculator, the second input end of the second comparator is connected to a cabinet internal temperature sensor, and the output end of the second comparator is connected to a heater. Among them, the second comparator is used to detect whether condensation may occur inside the control cabinet according to the dew point temperature and the cabinet internal temperature. The first input end of the PID controller is connected to the first comparator, the second input end of the PID controller is connected to the motor temperature sensor, and the output end of the PID controller is connected to a frequency converter. Among them, the PID controller is used to adjust the magnitude of the excitation current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor.

[0066] Among them, the dew point calculator, the first comparator 144, and the PID controller in the heating control device of this embodiment are respectively consistent with the functions of the dew point calculator, the comparator, and the PID controller in the previous embodiment, and will not be elaborated here. Different from the previous embodiment, a second comparator 145 is additionally provided in the heating control device of this embodiment. The second comparator includes a first input end, a second input end, and an output end. The dew point calculator further includes a second output end. The second output end of the dew point calculator is connected to the first input end of the second comparator. The second input end of the second comparator is connected to a cabinet internal temperature sensor, and the output end of the second comparator is connected to a frequency converter;

[0067] The first input end In1 of the second comparator receives the dew point temperature T1 sent by the dew point calculator, and the second input end In2 of the second comparator receives the motor temperature T2 sent by the cabinet internal temperature sensor;

[0068] The second comparator is used to detect whether condensation may occur inside the control cabinet according to the dew point temperature and the temperature inside the cabinet. Specifically, the second comparator is used to compare the dew point temperature T1 with the motor temperature T3. If T3 ≤ T1, the second comparator determines that condensation has occurred or is about to occur inside the control cabinet, and sends an enabling signal to the heater through the output terminal Out of the second comparator. If T3 > T1 and lasts for a period of time, the second comparator determines that condensation has not occurred inside the control cabinet and will not occur soon, and sends a disabling signal to the heater through the output terminal Out of the comparator to turn off the heater.

[0069] For example, in combination with a water pump unit, based on the water pump unit as shown in Figure 3 the present application provides a specific example, as shown in Figure 7 shown, the heating control device 140 includes a dew point calculator 141, a first comparator 144, a second comparator 145, and a PID controller 143. The dew point calculator 141 includes an input terminal In, a first output terminal Out1, and a second output terminal Out2. The first comparator 144 includes a first input terminal In1, a second input terminal In2, and an output terminal Out. The second comparator includes a first input terminal In1, a second input terminal In2, and an output terminal Out. The PID controller 143 includes a first input terminal In1, a second input terminal In2, and an output terminal Out. The input terminal In of the dew point calculator 141 is connected to the output terminal of the ambient temperature and humidity sensor 160. The first output terminal Out1 of the dew point calculator 141 is connected to the first input terminal In1 of the first comparator. The second input terminal In2 of the first comparator is connected to the output terminal of the motor temperature sensor 150. The output terminal Out of the first comparator is connected to the first input terminal In1 of the PID controller 143. The second input terminal of the PID controller 143 is connected to the output terminal of the motor temperature sensor 150. The output terminal of the PID controller 143 is connected to the frequency converter 120. The second output terminal Out2 of the dew point calculator 141 is connected to the first input terminal In1 of the second comparator. The second input terminal In2 of the second comparator is connected to the temperature sensor inside the cabinet 170. The output terminal of the second comparator is connected to the input terminal of the heater 180.

[0070] It should be noted that in Figure 7 , for the connection method between the output terminal of the PID controller 143 and the input terminal of the frequency converter 120, and the setting method of the stop heating switch 190 in its connection, and the connection method between the second input terminal of the PID controller 143 and the temperature sensor in the water pump motor 130, reference can be made to the description in the previous text for Figure 6 and will not be elaborated here. In addition, Figure 7 the connection method between the first comparator in Figure 6The description of the connection mode of the comparator 142 and the motor temperature sensor 150 in [the relevant context] will not be elaborated here.

[0071] It should also be noted that the dew point calculator 141 in this application can be a central processing unit (CPU), a general-purpose processor, a coprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The dew point calculator 141 can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of 5SP and a microprocessor, etc. In this embodiment, the dew point calculator 141 can adopt a single-chip microcomputer, and various control functions can be realized by programming the single-chip microcomputer. The processor has the advantages of strong computing power and fast processing speed. The PID controller 143 in this application is a Proportional-Integral-Derivative (PID) controller. The PID controller 143 calculates the control quantity based on the input quantity using proportional (P), integral (I), and derivative (D), and controls the controlled object based on this control quantity, so that the output value of the controlled object reaches or approaches the desired set value. In this application, the PID controller 143 calculates the control signal in real time based on the motor temperature of the water pump motor 130, and controls the motor temperature of the water pump motor 130 to reach or approach the dew point temperature by outputting the control signal to the frequency converter 120.

[0072] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combinations of these technical features do not conflict, they should be considered as within the scope described in this specification.

[0073] The above embodiments only represent several implementation manners of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several deformations and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of this application patent shall be subject to the appended claims.

Claims

1. A water pump unit, comprising a control cabinet, a frequency converter and a water pump motor, characterized in that: The water pump unit also includes a heating control device and a motor temperature sensor; The first input end of the heating control device is connected to a motor temperature sensor, wherein the motor temperature sensor is arranged inside the water pump motor, and the motor temperature sensor is used to detect the motor temperature inside the motor; The first output end of the heating control device is connected to the water pump motor through a frequency converter, wherein the heating control device and the frequency converter are arranged inside the control cabinet, and the heating control device is used to control the frequency converter to only output excitation current according to the motor temperature, so that the water pump motor generates heat when it is stopped to eliminate condensation inside the motor.

2. The water pump unit according to claim 1, characterized in that: The water pump unit also includes an environmental temperature and humidity sensor, which is arranged outside the control cabinet and the water pump motor; The second input end of the heating control device is connected to the ambient temperature and humidity sensor, wherein the ambient temperature and humidity sensor is used to detect the ambient temperature and humidity, and the heating control device is used to detect whether condensation may occur inside the motor based on the ambient temperature and humidity and the motor temperature.

3. The water pump unit according to claim 2, characterized in that: The water pump unit also includes a temperature sensor and a heater in the cabinet; The third input end of the heating control device is connected to the cabinet temperature sensor, wherein the cabinet temperature sensor is arranged in the control cabinet, and the cabinet temperature sensor is used to detect the cabinet temperature of the control cabinet, and the heating control device is used to detect whether condensation may occur inside the control cabinet according to the ambient temperature and humidity and the cabinet temperature; The second output end of the heating control device is connected to the heater, wherein the heater is arranged in the control cabinet, the heater is used to heat the control cabinet to eliminate condensation in the cabinet, and the heating control device is also used to control the heater to heat the control cabinet to eliminate condensation in the cabinet.

4. The water pump unit according to claim 1, characterized in that: The water pump unit includes a plurality of frequency converters and a plurality of water pump motors, the heating control device includes a plurality of first output ends and a plurality of first input ends, and the number of water pump motors, frequency converters, first output ends and first input ends is consistent; Among them, each first output end of the heating control device is connected one-to-one with the corresponding frequency converter, each frequency converter is connected one-to-one with the corresponding water pump motor, and each first input end of the heating control device is connected one-to-one with the motor temperature sensor in the corresponding water pump motor.

5. The water pump unit according to claim 3, characterized in that: The in-cabinet temperature sensor is arranged at the ventilation filter window of the control cabinet, and the ventilation filter window is located above the side wall of the control cabinet.

6. The water pump unit according to claim 3 or 5, characterized in that: The heater is arranged below the side wall of the control cabinet.

7. The water pump unit according to claim 1, characterized in that: The water pump unit also includes a shutdown heating switch, and the heating control device is connected to the frequency converter via the shutdown heating switch. When the shutdown heating switch is closed, the heating control device is connected to the frequency converter, and the water pump motor switches from a normal working state to a shutdown heating state.

8. A heating control device, characterized in that: The heating control device is applied to the water pump unit according to any one of claims 1 to 7, wherein: The first input terminal of the heating control device is connected to the motor temperature sensor; The first output end of the heating control device is connected to the water pump motor through a frequency converter, wherein the heating control device and the frequency converter are arranged inside the control cabinet, and the heating control device is used to control the frequency converter to only output excitation current according to the motor temperature, so that the water pump motor generates heat when it is stopped to eliminate condensation inside the motor.

9. The heating control device according to claim 8, characterized in that: The heating control device includes a dew point calculator, a comparator and a PID controller; The input end of the dew point calculator is connected to the ambient temperature and humidity sensor, and the output end of the dew point calculator is connected to the comparator, wherein the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity; The first input end of the comparator is connected to the dew point calculator, the second input end of the comparator is connected to the motor temperature sensor, and the output end of the comparator is connected to the PID controller, wherein the comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature; The first input end of the PID controller is connected to the comparator, the second input end of the PID controller is connected to the motor temperature sensor, and the output end of the PID controller is connected to the frequency converter, wherein the PID controller is used to adjust the magnitude of the excitation current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor.

10. The heating control device according to claim 8, characterized in that: The heating control device includes a dew point calculator, a first comparator, a second comparator and a PID controller; The input end of the dew point calculator is connected to the ambient temperature and humidity sensor, the first output end of the dew point calculator is connected to the first comparator, and the second output end of the dew point calculator is connected to the second comparator, wherein the dew point calculator is used to calculate the dew point temperature according to the ambient temperature and humidity; A first input end of the first comparator is connected to a dew point calculator, a second input end of the first comparator is connected to a motor temperature sensor, and an output end of the first comparator is connected to a PID controller, wherein the first comparator is used to detect whether condensation may occur inside the motor according to the dew point temperature and the motor temperature; The first input end of the second comparator is connected to the dew point calculator, the second input end of the second comparator is connected to the cabinet temperature sensor, and the output end of the second comparator is connected to the heater, wherein the second comparator is used to detect whether condensation may occur inside the control cabinet according to the dew point temperature and the cabinet temperature; The first input end of the PID controller is connected to the first comparator, the second input end of the PID controller is connected to the motor temperature sensor, and the output end of the PID controller is connected to the frequency converter, wherein the PID controller is used to adjust the magnitude of the excitation current output by the frequency converter in real time according to the motor temperature to eliminate condensation inside the motor.

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