Control system and method of diaphragm booster pump for water purifier

Abstract

The present invention discloses a diaphragm booster pump control system and method for a water purifier, the diaphragm booster pump control system for a water purifier includes an LED display panel, a switching power supply module and a booster pump variable frequency drive module, the switching power supply module is used to power the LED display panel and the booster pump variable frequency drive module, the LED display panel is used to display the current working status of the water purifier, and the corresponding flow switch instruction is generated by selecting the output flow of the water purifier; the booster pump variable frequency drive module includes an MCU main control, a power inverter and a brushless diaphragm booster pump motor, the MCU main control receives the flow switch instruction issued by the LED display panel, and uses the AI ​​curve corresponding to the flow-pressure-speed. The diaphragm booster pump control system and method for a water purifier disclosed by the present invention are intended to solve the problems of small water output, large volume, and certain safety hazards of the water purifier.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor control in the water purifier industry, and in particular relates to a diaphragm booster pump control system for a water purifier and a diaphragm booster pump control method for a water purifier. Background Art

[0002] Safe drinking water is the basic guarantee of human health and an important public health resource related to the people's livelihood. Drinking water is different from using water. The safety, quality and health of the water you drink need to be paid more attention to. The water purifier grasps this important link of "intake water". In the water purification equipment market, small products, large flux, low noise and high reliability have become the focus of users. As the water output of the pure water machine increases, the power of the booster pump also needs to increase. As a result, the volume of the booster pump increases, the noise increases, the vibration increases, and the user experience is not good.

[0003] At present, there are the following problems in the water purifier control solution:

[0004] 1. Traditional water purifier solutions mostly use brush motors, which have problems such as brush wear, electromagnetic interference, relatively low efficiency, difficulty in achieving high-speed operation, high noise and poor reliability.

[0005] 2. Traditional control water pumps often control the start and stop of the water pump by the closure of the relay. It is impossible to perform PWM speed regulation and cannot meet people's needs for different flow rates.

[0006] 3. The brushed motor used in the traditional control method will freeze in the water pipes when the ambient temperature is below 0 degrees Celsius in winter. When the water purifier is in use, the current increases, which can easily cause the motor temperature to rise. In severe cases, the motor will be burned and a certain degree of safety hazard will be increased.

[0007] 4. In the traditional household water purifier control method, a transformer is required. The specifications of transformers on the market are different, especially those above 24V / 3A, which are large in size, high in price and cost, and require separate safety certification.

[0008] 5. Traditional water purifiers are usually large in size and require a large space for installation, which brings a lot of inconvenience to families with small kitchen water purification space.

[0009] Therefore, further improvements are made to the above problems. Summary of the invention

[0010] The main purpose of the present invention is to provide a diaphragm booster pump control system and method for a water purifier, aiming to solve the problems of small water output, large volume and certain safety hazards of the above-mentioned water purifier.

[0011] To achieve the above purpose, the present invention provides a diaphragm booster pump control system for a water purifier, comprising an LED display panel, a switching power supply module and a booster pump variable frequency drive module, wherein the switching power supply module is used to supply power to the LED display panel and the booster pump variable frequency drive module, wherein:

[0012] The LED display panel is used to display the current working status of the water purifier, and to generate a corresponding flow switch instruction by selecting the output flow of the water purifier;

[0013] The boost pump variable frequency drive module includes an MCU main control, a power inverter and a brushless diaphragm boost pump motor (DC brushless motor). The MCU main control receives the flow switch command issued by the LED display panel, and controls the switching state of the power inverter and outputs the corresponding duty cycle through the AI ​​curve corresponding to the flow-pressure-speed, thereby realizing variable frequency control of the speed and flow of the brushless diaphragm boost pump motor and making the diaphragm boost pump output the corresponding matching precise flow.

[0014] As a further preferred technical solution of the above technical solution, the LED display panel includes an electronic control board MCU, a water inlet valve, a water outlet valve, a pressure switch and an LED display button, wherein:

[0015] When the water purifier receives a water inlet instruction (i.e., the LED display panel generates a flow switch instruction), the electronic control board MCU opens the water inlet valve through the first relay to allow water to enter the pipeline;

[0016] The pressure of the pipeline is detected. If the pressure is greater than or equal to the first pressure threshold (30psi), the electronic control board MCU turns on the pressure switch through the second relay (if it is less than the first pressure threshold, it means that the water pump is not turned on), so that the diaphragm booster pump starts working, and the electronic control board MCU turns on the water outlet valve through the third relay;

[0017] After the water outlet valve is opened, the MCU main control determines the pressure of the pipeline in real time and adjusts it according to the AI ​​curve. If the current pressure is greater than or equal to the second pressure threshold, the power inverter is controlled to make the brushless diaphragm booster pump motor enter the constant power + constant speed control mode, and after full stall, enter the stall protection mechanism; if the current pressure is less than the second pressure threshold, the AI ​​curve is used for frequency conversion control according to the flow switch instruction so that water can be discharged from the water purifier.

[0018] As a further preferred technical solution of the above technical solution, the constant power + constant speed control mode is specifically implemented as follows:

[0019] When the MCU main control input power is less than the preset power threshold (preferably 95W), the brushless diaphragm booster pump motor operates in constant speed mode;

[0020] When the load gradually increases and the MCU main control power exceeds the preset power threshold, the brushless diaphragm booster pump motor switches to constant power mode;

[0021] If the load continues to increase to the maximum load state (the water outlet is fully closed, and the fully closed pressure is 130psi-150Psi), the MCU main control input power is constant at the preset power threshold, and the brushless diaphragm booster pump motor speed decreases (when the outlet pressure changes rapidly from 0-135Psi, the motor control mode will quickly switch from constant speed control mode to constant power control mode).

[0022] As a further preferred technical solution of the above technical solution, the switching power supply module includes an EMI inductor, a rectifier, an electrolytic capacitor and a switching power supply, and the input 220V AC passes through the EMI inductor, the rectifier, the electrolytic capacitor and the switching power supply in sequence, wherein:

[0023] The EMI inductor is used to filter out the clutter and interference signals in the input 220V AC power (making the output power purer and more stable);

[0024] The rectifier rectifies and boosts the 220V AC to 310V AC, and filters out the spikes and ripples through the electrolytic capacitor to provide a stable voltage for the switching power supply, which respectively supplies power to the LED display panel, the MCU main control and the power inverter (etc.).

[0025] As a further preferred technical solution of the above technical solution, the control mode of the brushless diaphragm booster pump motor by the MCU main control is sensorless FOC control. Through FOC control, after receiving the flow switch command issued by the LED display panel, the MCU main control circuit converts it into an AI curve corresponding to the flow-pressure-speed, thereby realizing the speed and flow control of the brushless diaphragm booster pump motor, wherein:

[0026] According to the current pressure, the required speed value is obtained from the AI ​​curve and transmitted to the MCU main control through the VSP interface. The FOC control output controls the PWM signal of the power inverter, thereby realizing the speed control of the brushless DC motor and then controlling the flow of the water purifier.

[0027] In order to achieve the above objectives, the present invention also discloses a control method for a diaphragm booster pump for a water purifier, which is used to implement the control system of the diaphragm booster pump for a water purifier.

[0028] The beneficial effects of the present invention are:

[0029] In the traditional water purifier control scheme, the auxiliary power supply needs to use a transformer, which has different specifications, large volume, and needs to pass safety tests. In the present invention, the transformer is removed, the system cost is reduced, and the volume of the water purifier is reduced.

[0030] The brushless DC motor is used to increase the service life and improve safety. The motor speed is not limited by the power frequency, so the rated speed can be designed to be very high, which is beneficial to increase the motor capacity. The relay used to control the start and stop of the motor in the existing technology is removed, which reduces the system cost and the size of the water purifier.

[0031] The MCU main control realizes the speed and flow control of the DC brushless motor by converting the AI ​​curve corresponding to flow-pressure-speed, thereby obtaining the intelligent AI curve frequency conversion control of the flow of the brushless diaphragm booster pump.

[0032] The switch power supply system, brushless diaphragm booster pump motor, and booster pump variable frequency drive control are integrated to reduce the overall space of the water purifier. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic flow chart of a control system and method of a diaphragm booster pump for a water purifier of the present invention.

[0034] Figure 2 It is a schematic diagram of a booster pump variable frequency drive module of the diaphragm booster pump control system and method for a water purifier of the present invention.

[0035] Figure 3 It is a schematic diagram of a switch power supply module of a diaphragm booster pump control system and method for a water purifier of the present invention.

[0036] Figure 4 is a schematic diagram of a control system and method of a diaphragm booster pump for a water purifier of the present invention,

[0037] Figure 5 It is a schematic diagram of an AI curve of a control system and method of a diaphragm booster pump for a water purifier of the present invention. DETAILED DESCRIPTION

[0038] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0039] In the preferred embodiments of the present invention, those skilled in the art should note that the water purifier and the like involved in the present invention may be regarded as prior art.

[0040] Preferred embodiments.

[0041] like Figure 1-5 As shown, the present invention discloses a diaphragm booster pump control system for a water purifier, comprising an LED display panel, a switching power supply module and a booster pump variable frequency drive module, wherein the switching power supply module is used to supply power to the LED display panel and the booster pump variable frequency drive module, wherein:

[0042] The LED display panel is used to display the current working status of the water purifier (including flow display, fault display, etc.), and generate corresponding flow switch instructions by selecting the output flow (or other functions) of the water purifier;

[0043] The booster pump variable frequency drive module includes an MCU main control, a power inverter and a brushless diaphragm booster pump motor (DC brushless motor). The MCU main control receives the flow switch command issued by the LED display panel, and controls the switch state of the power inverter and outputs the corresponding duty cycle through the AI ​​curve corresponding to the flow-pressure-speed (under the conditions of the water inlet pressure of 30Psi and the given speed of 1600Rpm, by measuring the flow and speed under different pressures, which can improve the control accuracy and enhance the adaptability. Through the AI ​​control curve, the efficiency of the water purifier can be improved), thereby realizing the variable frequency control of the speed and flow of the brushless diaphragm booster pump motor and making the diaphragm booster pump output the corresponding matching precise flow (the role of the diaphragm booster pump in the control process is to receive the control signal, change the flow of the regulated medium, and maintain the regulated parameters within the required range, so as to achieve the automation of the production process. The speed can be adjusted by external input (0-5V) voltage to achieve the purpose of adjusting the flow).

[0044] Specifically, the LED display panel includes an electronic control board MCU, a water inlet valve, a water outlet valve, a pressure switch and an LED display button, wherein:

[0045] When the water purifier receives a water inlet instruction (i.e., the LED display panel generates a flow switch instruction), the electronic control board MCU opens the water inlet valve through the first relay to allow water to enter the pipeline;

[0046] The pressure of the pipeline is detected. If the pressure is greater than or equal to the first pressure threshold (30psi), the electronic control board MCU turns on the pressure switch through the second relay (if it is less than the first pressure threshold, it means that the water pump is not turned on), so that the diaphragm booster pump starts working, and the electronic control board MCU turns on the water outlet valve through the third relay;

[0047] After the outlet valve is opened, the MCU main control determines the pressure of the pipeline in real time and adjusts it according to the AI ​​curve. If the current pressure is greater than or equal to the second pressure threshold, the power inverter is controlled to make the brushless diaphragm booster pump motor enter the constant power + constant speed control mode, and after full stall, enter the stall protection mechanism (when the speed is lower than the set constant speed threshold, it indicates that the motor may have abnormal deceleration. At the same time, the system will also detect the power of the motor. If the power exceeds the preset constant power threshold while the speed decreases, it further confirms that the motor is in a stalled state and is about to enter a stalled state, thereby triggering the stall protection); if the current pressure is less than the second pressure threshold, the AI ​​curve is used for frequency conversion control according to the flow switch instruction so that water can be discharged from the water purifier (the AI ​​curve is a function curve of pressure flow and speed. After receiving the flow instruction, the MCU main control will make the diaphragm booster pump motor rotate at this speed according to the speed corresponding to the command flow on the AI ​​curve, so as to obtain the desired flow).

[0048] For stalling, the MCU main control is in a freezing state when the diaphragm booster pump is below 0 degrees Celsius or other water pipes are blocked. When the household water purifier is in use, the current increases, which can easily cause the motor temperature to rise and even burn the motor in severe cases. At this time, the MCU main control of the brushless motor diaphragm booster pump can perform stall protection through a control method of constant power combined with constant speed, greatly improving the public safety of household water purifiers and after-sales defective repairs.

[0049] More specifically, the constant power + constant speed control mode is implemented as follows:

[0050] When the MCU main control input power is less than the preset power threshold (preferably 95W), the brushless diaphragm booster pump motor operates in constant speed mode;

[0051] When the load gradually increases and the MCU main control power exceeds the preset power threshold, the brushless diaphragm booster pump motor switches to constant power mode;

[0052] If the load continues to increase to the maximum load state (the water outlet is fully closed, and the fully closed pressure is 130psi-150Psi), the MCU main control input power is constant at the preset power threshold, and the brushless diaphragm booster pump motor speed decreases (when the outlet pressure changes rapidly from 0-135Psi, the motor control mode will quickly switch from constant speed control mode to constant power control mode).

[0053] Furthermore, the switching power supply module includes an EMI inductor, a rectifier, an electrolytic capacitor and a switching power supply, and the input 220V AC passes through the EMI inductor, the rectifier, the electrolytic capacitor and the switching power supply in sequence, wherein:

[0054] The EMI inductor is used to filter out the clutter and interference signals in the input 220V AC power (making the output power purer and more stable);

[0055] The rectifier rectifies and boosts the 220V AC to 310V AC, and filters out the spikes and ripples through the electrolytic capacitor to provide a stable voltage for the switching power supply, which respectively supplies power to the LED display panel, the MCU main control and the power inverter (etc.).

[0056] Furthermore, the MCU main control uses sensorless FOC control to control the brushless diaphragm booster pump motor (eliminating the start and stop mode of the brush motor controlled by the relay switch in the traditional water purifier, while reducing the switch relay on the main control board, reducing the control cost and the installation size). Through FOC control, after receiving the flow switch command from the LED display panel, the MCU main control circuit converts it into the AI ​​curve corresponding to the flow-pressure-speed, thereby realizing the speed and flow control of the brushless diaphragm booster pump motor, where:

[0057] According to the current pressure, the required speed value is obtained from the AI ​​curve and transmitted to the MCU main control through the VSP interface (for speed regulation). The FOC control output controls the PWM signal of the power inverter, thereby realizing the speed control of the DC brushless motor and further controlling the flow of the water purifier (FOC control: through the conversion of Park and Clark's torque and excitation information to the three-phase inductance of the motor and appropriate switching of different SVPWM switching modes, a PWM wave is formed, and the actual flux vector formed is used to track its accurate flux circle).

[0058] It is worth mentioning that the present invention also uses the FG interface to feedback the rotation speed and fault signal, wherein:

[0059] FG feedback includes: FG speed feedback signal, FG fault feedback signal;

[0060] FG speed feedback signal: When the drive control system operates normally, the FG pin on the control board outputs a speed feedback signal. The speed can be obtained based on the feedback signal.

[0061] FG fault feedback signal: When a fault occurs in the drive control system, the FG pin on the control board outputs a corresponding fault signal according to the fault type, and the fault type is determined based on the feedback signal.

[0062] Preferably, the booster pump variable frequency drive module is integrated with the switching power supply module to support startup control or 0-5V speed regulation and 24V (0.5A-1A) output control.

[0063] The invention also discloses a control method of a diaphragm booster pump for a water purifier, which is used to implement the control system of the diaphragm booster pump for a water purifier.

[0064] It is worth mentioning that the technical features such as the water purifier involved in the patent application of this invention should be regarded as the prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional methods in the field, and should not be regarded as the inventive point of the patent of this invention. The patent of this invention will not be further elaborated.

[0065] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A diaphragm booster pump control system for a water purifier, characterized in that: It includes an LED display panel, a switching power supply module and a booster pump variable frequency drive module, wherein the switching power supply module is used to supply power to the LED display panel and the booster pump variable frequency drive module, wherein: The LED display panel is used to display the current working status of the water purifier, and to generate a corresponding flow switch instruction by selecting the output flow of the water purifier; The booster pump variable frequency drive module includes an MCU main control, a power inverter and a brushless diaphragm booster pump motor. The MCU main control receives the flow switch command issued by the LED display panel, and controls the switch state of the power inverter and outputs the corresponding duty cycle through the AI ​​curve corresponding to the flow-pressure-speed, thereby realizing the variable frequency control of the speed and flow of the brushless diaphragm booster pump motor and making the diaphragm booster pump output the corresponding matching precise flow; The LED display panel includes an electronic control board MCU, a water inlet valve, a water outlet valve, a pressure switch and an LED display button, wherein: When the water purifier receives a water inlet instruction, the electronic control board MCU opens the water inlet valve through the first relay to allow water to enter the pipeline; The pressure of the pipeline is detected. If the pressure is greater than or equal to the first pressure threshold, the electronic control board MCU turns on the pressure switch through the second relay, so that the diaphragm booster pump starts working, and the electronic control board MCU turns on the water outlet valve through the third relay; After the water outlet valve is opened, the MCU main control determines the pressure of the pipeline in real time and adjusts it according to the AI ​​curve. If the current pressure is greater than or equal to the second pressure threshold, the power inverter is controlled to make the brushless diaphragm booster pump motor enter the constant power + constant speed control mode, and after full stall, enter the stall protection mechanism; if the current pressure is less than the second pressure threshold, the AI ​​curve is used for frequency conversion control according to the flow switch instruction so that water can be discharged from the water purifier.

2. A diaphragm booster pump control system for a water purifier according to claim 1, characterized in that: The specific implementation of the constant power + constant speed control mode is as follows: When the MCU main control input power is less than the preset power threshold, the brushless diaphragm booster pump motor operates in constant speed mode; When the load gradually increases and the MCU main control power exceeds the preset power threshold, the brushless diaphragm booster pump motor switches to constant power mode.

3. A diaphragm booster pump control system for a water purifier according to claim 2, characterized in that: The switching power supply module includes an EMI inductor, a rectifier, an electrolytic capacitor and a switching power supply. The input 220V AC passes through the EMI inductor, the rectifier, the electrolytic capacitor and the switching power supply in sequence, wherein: The EMI inductor is used to filter out clutter and interference signals in the input 220V AC power; The rectifier rectifies and boosts the 220V AC to 310V AC, and filters out the spikes and ripples through the electrolytic capacitor to provide a stable voltage for the switching power supply, which respectively supplies power to the LED display panel, the MCU main control and the power inverter.

4. A diaphragm booster pump control system for a water purifier according to claim 3, characterized in that: The MCU main control uses sensorless FOC control to control the brushless diaphragm booster pump motor. Through FOC control, after receiving the flow switch command from the LED display panel, the MCU main control circuit converts it into an AI curve corresponding to the flow-pressure-speed, thereby realizing the speed and flow control of the brushless diaphragm booster pump motor.

5. A method for controlling a diaphragm booster pump for a water purifier, characterized in that: Used to implement a diaphragm booster pump control system for a water purifier as described in any one of claims 1-4.

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