Compatible voltage and current type constant voltage water supply device

Abstract

The utility model provides a compatible voltage and current type constant voltage water supply device relates to water supply technical field, including water pressure signal acquisition module, signal conditioning module, MCU control chip and water pump motor drive module. Water pressure signal acquisition module can compatible connection two line system current type or three line system voltage type water pressure sensor, signal conditioning module carries out filter, buffer and amplitude adjustment to the water pressure signal of collection, exports stable direct current voltage signal, MCU control chip compares this signal with setting value, generates control signal through PID algorithm, water pump motor drive module adjusts water pump motor rotating speed according to this signal. The utility model effectively solved the water pressure unstable problem caused by power fluctuation or sensor type difference, realized the high accuracy, high stability constant voltage water supply of terminal pipe network, especially applicable to photovoltaic solar energy and other unstable power supply of deep well pump system.

Description

Technical Field

[0001] This utility model mainly relates to the field of water supply technology, specifically to a constant pressure water supply device compatible with both voltage and current. Background Technology

[0002] With the widespread application of photovoltaic solar energy technology, solar-powered deep well pump systems have gradually become an important means of water supply in remote areas, rural areas, and areas without electricity due to their advantages such as energy saving, environmental protection, and low operating costs. However, a significant problem exists in the actual operation of this type of system: the output voltage of the solar panels is greatly affected by factors such as light intensity and temperature, resulting in significant fluctuations in the input voltage; in addition, the long water network pipelines and frequent changes in water flow velocity cause drastic fluctuations in water pressure at the user's terminal, seriously affecting the water user experience and equipment stability.

[0003] To address the aforementioned issues, traditional constant-pressure water supply control systems typically employ water pressure sensors to monitor pipeline pressure in real time and use a controller to adjust the pump motor speed to maintain constant water pressure. Currently, common water pressure sensors on the market mainly include two types: two-wire current-type (e.g., 4–20mA output) and three-wire voltage-type (e.g., 0–10V output). However, most existing water supply control devices only support one of these signal types, lacking compatibility with both sensor signals. This limits users' choice of sensor type, reduces system configuration flexibility, and increases the complexity of equipment replacement and maintenance.

[0004] It should be noted that the above content falls within the scope of technical knowledge of those skilled in the art. Due to the vast and complex nature of the technical content in this field, the above content of this application does not necessarily constitute prior art. Utility Model Content

[0005] 1. The technical problem to be solved by the utility model:

[0006] This utility model provides a constant pressure water supply device compatible with both voltage and current types, in order to solve the technical problems existing in the background art.

[0007] 2. Technical Solution:

[0008] To achieve the above objectives, the technical solution provided by this utility model is as follows: a constant pressure water supply device compatible with voltage and current, comprising a water pressure signal acquisition module, a signal conditioning module, an MCU control chip, and a water pump motor drive module;

[0009] The input terminal of the water pressure signal acquisition module is used to connect to an external water pressure sensor to acquire the simulated water pressure signal in the pipeline;

[0010] The input terminal of the signal conditioning module is connected to the output terminal of the water pressure signal acquisition module, and is used to filter and buffer the water pressure analog signal and output the processed DC voltage signal.

[0011] The analog signal input terminal of the MCU control chip is connected to the output terminal of the signal conditioning module, and its output terminal is connected to the control input terminal of the water pump motor drive module. The MCU control chip is used to compare and process the received DC voltage signal with the target water pressure value set by the user, and generate the corresponding water pump motor control signal.

[0012] The power output terminal of the water pump motor drive module is connected to the water pump motor and is used to adjust the operating speed of the water pump motor according to the control signal.

[0013] In this application, the real-time water pressure signal acquired by the water pressure signal acquisition module is converted into a clean, standard DC voltage signal by the signal conditioning module and then sent to the MCU control chip. The MCU control chip compares this signal with the user-set value, calculates the deviation, and uses a PID algorithm to determine how to adjust the motor speed to eliminate the deviation. Subsequently, the MCU control chip outputs a corresponding control signal to the drive module, which then adjusts the water pump motor speed. The change in speed causes a change in pipeline water pressure, forming a closed-loop feedback control system, ultimately stabilizing the water pressure in the terminal network near the user-set target value, thus achieving constant pressure water supply.

[0014] Furthermore, the water pressure signal acquisition module is configured to be compatible with two-wire current-type water pressure sensors or three-wire voltage-type water pressure sensors through hardware circuit switching or interface adaptation.

[0015] Furthermore, when a two-wire current-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence:

[0016] A parallel sampling resistor network is used to convert a 4-20mA current signal into a voltage signal;

[0017] A π-type RC passive low-pass filter is used for primary filtering.

[0018] Input voltage follower, used for impedance matching and signal buffering;

[0019] A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering.

[0020] Anti-self-oscillation output voltage follower, used for signal isolation and enhanced load capacity;

[0021] A first-order RC passive low-pass filter is used for final filtering before the output.

[0022] Furthermore, when a three-wire voltage-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence:

[0023] A π-type RC passive low-pass filter is used for primary filtering of 0-10V voltage signals.

[0024] Input voltage follower, used for impedance matching and signal buffering;

[0025] A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering.

[0026] Anti-self-oscillation output voltage follower, used for signal isolation and enhanced load capacity;

[0027] A first-order RC passive low-pass filter is used for final filtering before the output.

[0028] Furthermore, both the input voltage follower and the anti-self-oscillating output voltage follower are powered by an independent bias power supply.

[0029] Furthermore, the MCU control chip has a built-in analog-to-digital converter, which is used to convert the analog DC voltage signal output by the signal conditioning module into a digital signal for processing.

[0030] Furthermore, this device is specifically applied to photovoltaic solar deep well water pump systems to achieve constant pressure water supply to the terminal pipe network.

[0031] 3. Beneficial effects:

[0032] Compared with the prior art, the technical solution provided by this utility model has the following advantages:

[0033] This invention features a reasonable design that significantly improves system applicability and flexibility by being compatible with two mainstream industrial sensor signal types. Its multi-stage RC filter and voltage follower combination conditioning circuit effectively suppresses various interferences during long-distance transmission and in complex field environments, ensuring high accuracy and stability of the water pressure sampling signal and laying a solid foundation for precise control.

[0034] By employing an independent bias power supply to power key analog components and combining it with the MCU's built-in ADC for sampling, the system's power supply noise suppression and anti-interference capabilities are greatly enhanced. This design simplifies the peripheral circuitry, reduces costs, and achieves rapid response and stable control of the terminal water pressure through dynamic adjustment of the pump speed using a PID closed-loop algorithm.

[0035] It should be noted that the structures not described in this utility model are the same as or can be implemented using existing technology, and will not be elaborated here, as they do not involve the design points and improvement directions of this utility model. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the control flow of this utility model;

[0037] Figure 2 This is a flowchart illustrating the signal conditioning module of this utility model;

[0038] Figure 3 This utility model relates to a current-type constant pressure water supply device and a voltage-type constant pressure water supply device.

[0039] Circuit schematic. Detailed Implementation

[0040] To facilitate understanding of this utility model, a more comprehensive description of the utility model will be given below with reference to the accompanying drawings, which show several embodiments of the utility model. However, the utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the utility model will be more thorough and complete.

[0041] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "page", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0043] In this utility model, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "fixed," "provided with," and "located in" 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 of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0044] It should be noted that the structures not described in this utility model do not involve the design points and improvement directions of this utility model, and can all adopt existing technologies known to those skilled in the art.

[0045] The specific implementation of this utility model will be described in detail below with reference to specific embodiments.

[0046] See attached document Figure 1-3 A constant pressure water supply device compatible with voltage and current types includes a water pressure signal acquisition module, a signal conditioning module, an MCU control chip, and a water pump motor drive module.

[0047] The input terminal of the water pressure signal acquisition module is used to connect to an external water pressure sensor to acquire the simulated water pressure signal in the pipeline;

[0048] The input terminal of the signal conditioning module is connected to the output terminal of the water pressure signal acquisition module, and is used to filter and buffer the water pressure analog signal and output the processed DC voltage signal.

[0049] The analog signal input terminal of the MCU control chip is connected to the output terminal of the signal conditioning module, and its output terminal is connected to the control input terminal of the water pump motor drive module. The MCU control chip is used to compare and process the received DC voltage signal with the target water pressure value set by the user, and generate the corresponding water pump motor control signal.

[0050] The power output terminal of the water pump motor drive module is connected to the water pump motor and is used to adjust the operating speed of the water pump motor according to the control signal.

[0051] In this embodiment, the real-time water pressure signal acquired by the water pressure signal acquisition module is converted into a clean, standard DC voltage signal by the signal conditioning module and then sent to the MCU control chip. The MCU control chip compares this signal with the user-set value, calculates the deviation, and uses a PID algorithm to determine how to adjust the motor speed to eliminate the deviation. Subsequently, the MCU control chip outputs a corresponding control signal to the drive module, which then adjusts the water pump motor speed. The change in speed causes a change in pipeline water pressure, forming a closed-loop feedback control system, ultimately stabilizing the water pressure in the terminal network near the user-set target value, achieving constant pressure water supply.

[0052] The water pressure signal acquisition module is configured to be compatible with two-wire current-type water pressure sensors or three-wire voltage-type water pressure sensors through hardware circuit switching or interface adaptation. Users insert the two-wire current-type or three-wire voltage-type water pressure sensor into the corresponding interface based on the sensor type available on site, and the device identifies and acquires the signal. Whether the current signal is converted to voltage by the sampling resistor or the directly input voltage signal, it will be processed by a unified signal conditioning module to ensure that the signal sent to the MCU is a standard, clean DC voltage signal, thus providing a reliable input basis for achieving precise constant pressure control.

[0053] When a two-wire current-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence:

[0054] A parallel sampling resistor network is used to convert a 4-20mA current signal into a voltage signal;

[0055] A π-type RC passive low-pass filter is used for primary filtering.

[0056] Input voltage follower, used for impedance matching and signal buffering;

[0057] A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering.

[0058] Anti-self-oscillation output voltage follower, used for signal isolation and enhanced load capacity;

[0059] A first-order RC passive low-pass filter is used for final filtering before the output.

[0060] When a two-wire current sensor is connected, the 4-20mA loop current it generates flows through the parallel sampling resistor network at the front end of the signal conditioning module. This network accurately converts the current signal into a voltage signal.

[0061] The voltage signal first enters a π-type RC passive low-pass filter. This filter can effectively attenuate high-frequency interference noise coupled in from the industrial field through the long sensor cable, completing the primary filtering of the signal.

[0062] The signal after primary filtering is fed into an input voltage follower. This follower provides high input impedance, which greatly reduces the load effect on the preceding π-type filter and avoids signal attenuation due to output impedance. At the same time, it provides low output impedance, acting as an ideal "buffer" to isolate the preceding and following circuits, ensuring distortion-free signal transmission.

[0063] The buffered signal enters a first-order RC passive low-pass filter with a resistor divider to further filter out residual noise.

[0064] The adjusted signal enters an anti-self-oscillation output voltage follower. This circuit typically includes a small feedback capacitor or compensation network to suppress potential high-frequency self-oscillations and ensure stable circuit operation.

[0065] The signal finally passes through a first-order RC passive low-pass filter for final filtering before output. This ensures that the analog signal fed into the MCU is an extremely pure and stable DC voltage signal, and provides a precise and stable conversion reference for the current signal through a dedicated sampling resistor network, ensuring the accuracy of the initial signal.

[0066] When a three-wire voltage-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence:

[0067] A π-type RC passive low-pass filter is used for primary filtering of 0-10V voltage signals.

[0068] Input voltage follower, used for impedance matching and signal buffering;

[0069] A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering.

[0070] Anti-self-oscillation output voltage follower, used for signal isolation and enhanced load capacity;

[0071] A first-order RC passive low-pass filter is used for final filtering before the output.

[0072] When a three-wire voltage sensor is connected, its output 0-10V voltage signal first enters a π-type RC passive low-pass filter. This filter effectively attenuates high-frequency interference noise coupled in from the industrial field through the sensor's long cable, completing the primary filtering of the signal and protecting subsequent circuits from impact.

[0073] The signal after primary filtering is fed into an input voltage follower. This follower provides high input impedance, which greatly reduces the load effect on the preceding π-type filter and avoids signal attenuation due to output impedance. At the same time, it provides low output impedance, acting as an ideal "buffer" to isolate the preceding and following circuits, ensuring distortion-free signal transmission.

[0074] The buffered signal enters a first-order RC passive low-pass filter with a resistor divider. This further filters out residual noise and improves signal quality.

[0075] The adjusted signal enters an anti-self-oscillation output voltage follower. This circuit typically includes a small feedback capacitor or compensation network to suppress potential high-frequency self-oscillations and ensure stable circuit operation.

[0076] The signal finally passes through a first-order RC passive low-pass filter for final filtering before output. This ensures that the analog signal sent to the MCU is an extremely pure and stable DC voltage signal. Through a resistor divider network, it can perfectly adapt to the industrial standard 0-10V voltage signal input and linearly adjust it to the safe voltage range that the MCU can handle. It also provides excellent noise suppression capabilities, effectively eliminating power frequency and high-frequency interference coupled in long-distance transmission, ensuring the measurement accuracy of the water pressure signal and the stability of the system.

[0077] Both the input voltage follower and the anti-self-oscillating output voltage follower are powered by an independent bias power supply. The bias power supply is separately led to the power supply pins of the input voltage follower and the anti-self-oscillating output voltage follower to power these two key operational amplifier units. This isolates the power supply of these two followers from the power supply of other power-consuming units in the system at the DC level, significantly reducing ground loop coupling interference, improving the common-mode rejection ratio of the entire signal acquisition system, and reducing dependence on the quality of the main power supply. This enhances the anti-interference capability and operational reliability of the device in complex industrial power supply environments.

[0078] The MCU control chip has a built-in analog-to-digital converter, which is used to convert the analog DC voltage signal output by the signal conditioning module into a digital signal for processing. The MCU control chip adopts existing technology, and the STM32G070 series integrates a high-precision 12-bit successive approximation (SAR) ADC module.

[0079] This device is specifically applied to photovoltaic solar deep well water pump systems to achieve constant pressure water supply to the terminal pipe network, effectively solving the problem of unstable water pressure caused by power supply fluctuations.

[0080] The above-described embodiments are merely illustrative of certain implementations of this utility model, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A constant pressure water supply device compatible with both voltage and current types, characterized in that: Water pressure signal acquisition module, signal conditioning module, MCU control chip, and water pump motor drive module; The input terminal of the water pressure signal acquisition module is used to connect to an external water pressure sensor to acquire the simulated water pressure signal in the pipeline; The input terminal of the signal conditioning module is connected to the output terminal of the water pressure signal acquisition module, and is used to filter and buffer the water pressure analog signal and output the processed DC voltage signal. The analog signal input terminal of the MCU control chip is connected to the output terminal of the signal conditioning module, and its output terminal is connected to the control input terminal of the water pump motor drive module. The MCU control chip is used to compare and process the received DC voltage signal with the target water pressure value set by the user, and generate the corresponding water pump motor control signal. The power output terminal of the water pump motor drive module is connected to the water pump motor and is used to adjust the operating speed of the water pump motor according to the control signal.

2. The voltage and current compatible constant pressure water supply device according to claim 1, characterized in that: The water pressure signal acquisition module is configured to be compatible with two-wire current-type water pressure sensors or three-wire voltage-type water pressure sensors through hardware circuit switching or interface adaptation.

3. The constant pressure water supply device compatible with both voltage and current types according to claim 1, characterized in that: When a two-wire current-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence: A parallel sampling resistor network is used to convert a 4-20mA current signal into a voltage signal; A π-type RC passive low-pass filter is used for primary filtering. Input voltage follower, used for impedance matching and signal buffering; A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering. Anti-self-excitation output voltage follower, used for signal isolation and enhanced load capacity; A first-order RC passive low-pass filter is used for final filtering before the output.

4. A constant pressure water supply device compatible with both voltage and current types according to claim 1, characterized in that: When a three-wire voltage-type water pressure sensor is connected, the signal conditioning module includes the following components connected in sequence: A π-type RC passive low-pass filter is used for primary filtering of 0-10V voltage signals. Input voltage follower, used for impedance matching and signal buffering; A resistor-divider type first-order RC passive low-pass filter is used for signal amplitude adjustment and secondary filtering. Anti-self-oscillation output voltage follower, used for signal isolation and enhanced load capacity; A first-order RC passive low-pass filter is used for final filtering before the output.

5. A constant pressure water supply device compatible with both voltage and current types according to claim 3 or 4, characterized in that: Both the input voltage follower and the anti-self-oscillating output voltage follower are powered by an independent bias power supply.

6. A constant pressure water supply device compatible with both voltage and current types according to claim 1, characterized in that: The MCU control chip has a built-in analog-to-digital converter, which is used to convert the analog DC voltage signal output by the signal conditioning module into a digital signal for processing.

7. A constant pressure water supply device compatible with both voltage and current types according to claim 1, characterized in that: This device is specifically used in photovoltaic solar deep well water pump systems to achieve constant pressure water supply to the terminal pipe network.

Images