Dynamic-precision-adjustable low-power-consumption light-stabilizing water turbidity detection method and device
By identifying water supply type and dynamically adjusting PWM resolution, a turbidity detection method was developed, which solved the problem of high accuracy and low power consumption in water turbidity detection in differentiated water supply scenarios. This method enables automatic adaptation and convenient water supply control, improving the balance between detection accuracy and power consumption.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-04-03
AI Technical Summary
Existing water turbidity detection technologies cannot adapt to different water supply scenarios, resulting in high power consumption for high-precision water detection, unreliability for low-precision water detection, and a lack of automatic identification and accuracy matching, making operation cumbersome.
By identifying water supply type, dynamically adjusting PWM resolution and turbidity detection, and combining lightweight temperature drift compensation, high-precision detection and low-power operation are achieved, integrating water supply control functions to adapt to different water supply scenarios.
It achieves a balance between high-precision water usage detection accuracy and low power consumption, automatically identifies water supply types without requiring manual mode switching, and improves practicality and convenience in multiple scenarios.
Smart Images
Figure CN121783853A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of water quality testing technology, and in particular to a low-power, stable-light method and apparatus for detecting water turbidity with dynamically adjustable precision. Background Technology
[0002] In the field of water quality testing, there are various differentiated water supply scenarios, and the requirements for turbidity detection accuracy vary significantly depending on the scenario. For example, one type of water (such as drinking water and food processing water) requires strict control of turbidity, demanding extremely high detection accuracy; another type of water (such as washing, cleaning, and industrial cooling water) only needs to meet basic hygiene or process requirements, with lower requirements for detection accuracy, and is usually used in large quantities and tested frequently.
[0003] Existing water turbidity detection technologies mostly employ a single-precision light source driving mode. Using high-precision driving to meet the demands of high-precision water quality detection would lead to performance overkill and excessive power consumption in low-precision water quality detection scenarios, failing to meet the general requirements of low power consumption and long battery life for various scenarios. Conversely, using low-precision driving would compromise the reliability of high-precision water quality detection. Furthermore, existing water turbidity detection technologies lack targeted designs for differentiated water supply scenarios, failing to automatically identify water supply types and match corresponding detection accuracies, requiring manual mode switching, which is cumbersome. Moreover, they do not consider the differences in turbidity ranges under different water supply types, and the generalized accuracy adjustment logic cannot adapt to the specific needs of various scenarios.
[0004] To address the aforementioned issues, there is an urgent need for a universal detection method that can accurately adapt to differentiated water supply scenarios, achieve integrated water supply type identification and dynamic accuracy matching, and coordinated water supply control. This method must ensure the detection accuracy of high-precision water use while reducing the power consumption of low-precision water use detection. Summary of the Invention
[0005] To address the shortcomings of existing technologies, this invention provides a low-power, stable-light water turbidity detection method and device with dynamically adjustable precision. It accurately adapts to different water supply scenarios by automatically identifying the water supply type and matching the precision range, and then dynamically adjusting the PWM resolution of the light source according to the turbidity within the range. Combined with lightweight temperature drift compensation, it achieves a balance between high-precision detection and low-power operation. At the same time, it integrates detection and water supply control functions, improving its practicality and convenience in multiple scenarios.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: A low-power, stable-light method for detecting water turbidity with dynamically adjustable precision, adaptable to differentiated water supply scenarios, including Class I and Class II water supply scenarios. The method includes the following steps: S1. Water supply type identification: Obtain the identification signal of the water supply channel and determine whether the current water supply type is Class I or Class II based on the identification signal; S2. Precision Range Matching: Match the corresponding PWM resolution range according to the water supply type. Specifically, the second type of water supply matches the low-bit PWM resolution range, which is 8-12 bits; the first type of water supply matches the high-bit PWM resolution range, which is 14-16 bits. S3. Turbidity detection and resolution fine-tuning: The light source module is activated to illuminate the water sample. The light signal is collected by the turbidity detection module and the real-time turbidity value is calculated. Within the PWM resolution range matched in step S2, the precise PWM resolution is determined based on the real-time turbidity value. S4. Low-power steady light drive: Based on the precise PWM resolution determined in step S3, the constant current drive module outputs a stable current to drive the light source module to emit light, thus completing the turbidity detection; S5. Water supply control: Output control signal based on turbidity detection results. If the turbidity of the first type of water supply exceeds the standard, cut off the corresponding water supply channel and issue an alarm; if the turbidity of the second type of water supply exceeds the standard, issue a warning.
[0007] Furthermore, in step S1, the water supply type identification is achieved through a flow detection element or a status detection element: the flow detection element collects the water flow signal of the water supply channel and transmits it to the main control module, and the main control module determines the water supply type based on the water flow characteristic threshold; the status detection element detects the working status of the treatment equipment on the water supply channel and determines the water supply type based on the working status.
[0008] Furthermore, in step S3, the rule for determining the precise PWM resolution is as follows: When the water supply type is Class II, if the real-time turbidity value is ≤1 NTU, a 12-bit PWM resolution is selected; if 1 NTU < real-time turbidity value ≤3 NTU, a 10-bit PWM resolution is selected; if the real-time turbidity value >3 NTU, an 8-bit PWM resolution is selected and an alarm is triggered. When the water supply type is Class I, if the real-time turbidity value is ≤0.5NTU, a 16-bit PWM resolution is selected; if 0.5NTU < real-time turbidity value ≤1NTU, a 14-bit PWM resolution is selected; if the real-time turbidity value >1NTU, a 14-bit PWM resolution is selected and an alarm is triggered.
[0009] Furthermore, in step S7, the turbidity exceedance threshold for the first type of water supply is 1 NTU, and the turbidity exceedance threshold for the second type of water supply is 3 NTU; the alarm method is an audible and visual alarm, and the warning method is a light warning or a voice prompt.
[0010] A low-power steady-state water turbidity detection device with adjustable dynamic precision is used to perform the above-mentioned low-power steady-state water turbidity detection method with adjustable dynamic precision. It includes a main control module, a light source module, a constant current drive module, a temperature detection module, a turbidity detection module, a water supply type identification module, a water supply control module, and a power supply module. The light source module is used to emit a detection beam to illuminate the water sample; The turbidity detection module includes a measurement optical path and a reference optical path, which are used to collect optical signals and convert them into electrical signals for transmission to the main control module; The constant current drive module is connected between the main control module and the light source module. It includes a PWM converter unit, an operational amplifier feedback unit, a resolution switching unit, and a bandwidth adjustment unit, and is used to output a stable current according to the control signal of the main control module. The temperature detection module is positioned close to the light source module and is used to collect the real-time temperature of the light source module and transmit it to the main control module. The water supply type identification module is used to collect the identification signal of the water supply channel and transmit it to the main control module; The water supply control module is used to control the on / off state of the water supply channel according to the control signals from the main control module; The power supply module provides power to the main control module, light source module, constant current drive module, temperature detection module, turbidity detection module, water supply type identification module, and water supply control module. The main control module is connected to the light source module, constant current drive module, temperature detection module, turbidity detection module, water supply type identification module, and water supply control module. The main control module has built-in water supply type identification logic, PWM resolution range matching rules, and temperature drift compensation curve to execute the above detection methods.
[0011] Furthermore, the resolution switching unit in the constant current drive module uses an analog switch to switch between different bit PWM resolutions; the bandwidth adjustment unit uses an adjustable resistor array to adjust the operational amplifier feedback bandwidth according to the PWM resolution, thereby improving current stability.
[0012] Furthermore, the light source module uses an infrared LED with a center wavelength of 860nm to avoid interference from pigments in the water sample on the detection results; the turbidity detection module uses a photodiode as its photosensitive element, and the temperature detection module uses a surface-mount thermistor.
[0013] Furthermore, the detection device is a water supply device adapted to a dual-line water supply scenario for household use, including an inlet end, a first outlet end, and a second outlet end; the water supply control module includes a filter, a first solenoid valve, and a second solenoid valve, with the filter connected in series between the inlet end and the second outlet end, and the first solenoid valve connected in series between the inlet end and the first outlet end; the water supply type identification module is a Hall effect flow sensor or a proximity switch, with the Hall effect flow sensor located between the inlet end and the water supply control module, and the proximity switch located at the filter outlet.
[0014] Compared with the prior art, the beneficial effects of the present invention are: This method adopts a general scenario division of Class I and Class II water supply to adapt to various differentiated water supply needs. Through a three-level precision control logic of water supply type, accuracy range, and turbidity fine-tuning, Class II water supply uses 8-12 bit low-bit PWM resolution, while Class I water supply uses 14-16 bit high-bit PWM resolution. On this basis, further fine-tuning based on turbidity is carried out, which not only ensures the detection accuracy of Class I water supply, but also greatly reduces the detection power consumption of Class II water supply, achieving accurate adaptation in multiple scenarios. In practical applications, raw water that is not used for daily drinking is classified as Class II water supply, and drinking water is classified as Class I water supply. The water supply type identification module automatically determines the water supply type without the need for manual mode switching, and the detection results directly link to the water supply control. When the Class I water supply exceeds the standard, the water supply is automatically cut off, which can improve the safety and convenience of use.
[0015] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a block diagram showing the connection relationship between the various components of this invention; Figure 2 This is a block diagram of the circuit connection module of the present invention; Figure 3 This is a flowchart of the program of the present invention.
[0018] The reference numerals and names in the figure are as follows: Water inlet 1, first water outlet 2, second water outlet 3, water supply control module 4, main control module 5, light source module 6, constant current drive module 7, temperature detection module 8, turbidity detection module 9, water supply type identification module 10, alarm module 11, power supply module 12, water sample detection chamber 13, filter 41, first solenoid valve 42, second solenoid valve 43, PWM converter unit 71, operational amplifier feedback unit 72, resolution switching unit 73, bandwidth adjustment unit 74, measurement optical path 91, reference optical path 92. Detailed Implementation
[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0020] The present invention will be further described in detail below with reference to specific embodiments.
[0021] This embodiment takes a dual-supply household water scenario as an example to describe the detection method and device of the present invention in detail. In this scenario, the first type of water supply is drinking water that has been treated by a filter, and the second type of water supply is unfiltered tap water.
[0022] like Figure 1-2 As shown, the low-power steady-state water turbidity detection device with adjustable dynamic precision in this embodiment is a household dual-channel water supply device, including a water inlet 1, a first water outlet 2, a second water outlet 3, a water supply control module 4, a main control module 5, a light source module 6, a constant current drive module 7, a temperature detection module 8, a turbidity detection module 9, a water supply type identification module 10, an alarm module 11, a power supply module 12, and a water sample detection chamber 13; Water inlet 1 is connected to the municipal tap water supply through a pipeline to introduce raw water; The water supply control module 4 includes a filter 41, a first solenoid valve 42, and a second solenoid valve 43. The filter 41 is connected in series between the water inlet 1 and the second water outlet 3 to purify the raw water into drinking water. The first solenoid valve 42 is connected in series between the water inlet 1 and the first water outlet 2 to control the opening and closing of the tap water channel. The second solenoid valve 43 is connected in series between the filter 41 and the second water outlet 3 to control the opening and closing of the drinking water channel. The water supply type identification module 10 uses a Hall flow sensor, which is set between the water inlet 1 and the water supply control module 4 to collect the flow velocity and flow rate signals of the water flow and transmit them to the main control module 5. Since the tap water channel has no filtration resistance, the flow velocity is fast and the flow rate is large. The drinking water channel is filtered by the filter 41, so the flow velocity is slow and the flow rate is small. The main control module 5 has a built-in flow velocity threshold and determines the water supply type based on the signal from the Hall flow sensor. The light source module 6 is located inside the water sample detection chamber 13, which is connected in series between the water inlet 1 and the water supply control module 4. Raw water flows into the water sample detection chamber 13 through the water inlet 1 and then flows into the water supply control module 4 after the detection is completed. The light source module 6 uses an infrared LED with a center wavelength of 860nm to emit an infrared detection beam, avoiding interference from pigments in the water sample on the detection results. The turbidity detection module 9 includes a measurement optical path 91 and a reference optical path 92. The measurement optical path 91 is located on the side of the water sample detection cavity 13 and is used to receive the light beam scattered by the water sample. The reference optical path 92 is located on the same side as the light source module 6 and is used to directly receive the light beam emitted by the light source module 6. Both the measurement optical path 91 and the reference optical path 92 use photodiodes as photosensitive elements to convert the light signal into an electrical signal and transmit it to the main control module 5. The main control module 5 calculates the turbidity value based on the ratio of the two electrical signals to offset the slight fluctuations in the light intensity of the light source. The constant current drive module 7 is connected between the main control module 5 and the light source module 6, and includes a PWM conversion unit 71, an operational amplifier feedback unit 72, a resolution switching unit 73, and a bandwidth adjustment unit 74. The PWM conversion unit 71 uses a high-precision DAC chip to receive the PWM signal output from the main control module 5 and convert it into a DC control voltage. The resolution switching unit 73 uses an analog switch connected between the main control module 5 and the PWM conversion unit 71, and is used to switch between 8-bit, 10-bit, 12-bit, 14-bit, and 16-bit PWM resolutions according to the control signal from the main control module 5. The bandwidth adjustment unit 74 uses an adjustable resistor array connected between the main control module 5 and the operational amplifier feedback unit 72, and is used to adjust the feedback resistor value of the operational amplifier according to the PWM resolution, thereby adjusting the feedback bandwidth. The operational amplifier feedback unit 72 uses a low-power operational amplifier, which collects the operating current of the light source module 6 through a sampling resistor R2, compares the sampled voltage with the control voltage output by the PWM conversion unit 71, and outputs a stable current to drive the light source module 6 to emit light. The temperature detection module 8 uses a surface-mount thermistor, which is placed close to the pin of the LED in the light source module 6. It is used to collect the junction temperature of the LED and convert the temperature signal into a voltage signal to be transmitted to the main control module 5. Alarm module 11 includes a buzzer and LED indicator lights, and is connected to main control module 5; wherein, the LED indicator lights are set with red LEDs and yellow LEDs, the red LEDs and buzzer are used for the first type of water supply turbidity exceeding the standard alarm, and the yellow LEDs are used for the second type of water supply turbidity exceeding the standard early warning. Power module 12 is powered by a 12V DC power adapter and has a built-in power management unit that converts the 12V voltage into a stable 5V voltage output to power each module. like Figure 3 As shown, the main control module 5 uses a low-power MCU, which is connected to each module to perform the following detection methods: Step S1. Water supply type identification: The Hall flow sensor collects the water flow velocity signal at the water inlet 1 in real time and transmits it to the main control module 5. The main control module 5 determines whether the flow velocity is ≥1.5L / min. If so, it is determined to be the second type of water supply; if the flow velocity is ≤0.8L / min, it is determined to be the first type of water supply. Step S2. Precision range matching: The main control module 5 matches the PWM resolution range according to the judgment result: the second type of water supply matches the 8-12 bit low bit range, and the first type of water supply matches the 14-16 bit high bit range; Step S3. Turbidity Detection and Resolution Fine-tuning: The main control module 5 controls the constant current drive module 7 to drive the light source module 6 to emit light, illuminating the water sample in the water sample detection chamber 13; the measurement optical path 91 and reference optical path 92 of the turbidity detection module 9 collect the optical signal, convert it into an electrical signal and transmit it to the main control module 5. The main control module 5 calculates the real-time turbidity value and determines the precise PWM resolution according to the following rules: Category 2 water supply: If turbidity ≤ 1 NTU, select 12-bit PWM resolution; if 1 NTU < turbidity ≤ 3 NTU, select 10-bit PWM resolution; if turbidity > 3 NTU, select 8-bit PWM resolution and trigger a yellow LED warning. Class 1 water supply: If turbidity ≤ 0.5 NTU, select 16-bit PWM resolution; if 0.5 NTU < turbidity ≤ 1 NTU, select 14-bit PWM resolution; if turbidity > 1 NTU, select 14-bit PWM resolution and trigger the red LED to light up and the buzzer to sound an alarm. Step S4. Low-power steady light drive: The main control module 5 outputs a control signal to the resolution switching unit 73 and bandwidth adjustment unit 74 of the constant current drive module 7, switches to the precise PWM resolution determined in step S3, and adjusts the operational amplifier feedback bandwidth. The operational amplifier feedback unit 72 collects current through the sampling resistor and feeds it back, outputting a stable current to drive the light source module 6 to emit light, thus completing the turbidity detection. Step S5. Temperature drift compensation: The temperature detection module 8 collects the junction temperature of the LED in real time and transmits it to the main control module 5. The main control module 5 adjusts the duty cycle of the PWM signal according to the preset temperature and luminous efficacy decay curve. For every 5°C increase in temperature, the luminous efficacy decays by 3%. For example, when the temperature rises from 25°C to 35°C, the luminous efficacy decays by 6%. The main control module 5 increases the PWM duty cycle by 6% to ensure the LED luminous intensity is stable. Step S6. Low-power standby during detection gap: The main control module 5 sets the detection cycle to 2 seconds and the detection time to 0.3 seconds. During non-detection gaps, it outputs a low-power control signal to the constant current drive module 7, controls the resolution switching unit 73 to switch to 8-bit resolution, connects the maximum resistance resistor to the bandwidth adjustment unit 74, and simultaneously reduces the PWM duty cycle to the minimum, so that the LED driving current drops below 5μA, and enters the low-power standby state. Step S7. Water supply control: If the turbidity of the first type of water supply is detected to be >1 NTU, the main control module 5 immediately outputs a control signal to close the second solenoid valve 43, cut off the drinking water channel, and continuously alarms; if the turbidity of the second type of water supply is detected to be >3 NTU, the main control module 5 outputs a control signal to light up the yellow LED warning to remind the user to check the water source; if the turbidity returns to normal, the solenoid valve is controlled to resume on / off operation, and the alarm / warning is turned off.
[0023] It should be noted that the detection method of the present invention is not limited to domestic water scenarios. In other differentiated water supply scenarios such as industrial differentiated water supply scenarios and commercial water supply scenarios, it is only necessary to adjust the water supply type identification threshold in step S1, the turbidity threshold in step S3, and the PWM resolution range to achieve accurate adaptation and have wide applicability.
[0024] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.
Claims
1. A low-power, stable-light method for detecting water turbidity with dynamically adjustable precision, characterized in that, This method is applied to differentiated water supply scenarios, which include Class I and Class II water supply. The steps include: S1. Water supply type identification: Obtain the identification signal of the water supply channel and determine whether the current water supply type is Class I or Class II based on the identification signal; S2. Precision Range Matching: Match the corresponding PWM resolution range according to the water supply type. Specifically, the second type of water supply matches the low-bit PWM resolution range, which is 8-12 bits; the first type of water supply matches the high-bit PWM resolution range, which is 14-16 bits. S3. Turbidity detection and resolution fine-tuning: The light source module is activated to illuminate the water sample, the light signal is collected and the real-time turbidity value is calculated. Within the PWM resolution range matched in step S2, the precise PWM resolution is determined based on the real-time turbidity value. S4. Low-power steady light drive: Based on the precise PWM resolution determined in step S3, the constant current drive module outputs a stable current to drive the light source module to emit light, thus completing the turbidity detection; S5. Water supply control: Output control signal based on turbidity detection results. If the turbidity of the first type of water supply exceeds the standard, cut off the corresponding water supply channel and issue an alarm; if the turbidity of the second type of water supply exceeds the standard, issue a warning.
2. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, In step S1, the identification signal is obtained through a flow detection element or a status detection element; the flow detection element collects the water flow signal of the water supply channel, and the main control module determines the water supply type based on the water flow characteristic threshold; the status detection element detects the working status of the treatment equipment on the water supply channel and determines the water supply type based on the working status.
3. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, In step S3, the rule for determining the precise PWM resolution is as follows: When the water supply type is Class II, if the real-time turbidity value is ≤1 NTU, a 12-bit PWM resolution is selected; if 1 NTU < real-time turbidity value ≤3 NTU, a 10-bit PWM resolution is selected; if the real-time turbidity value >3 NTU, an 8-bit PWM resolution is selected and an alarm is triggered. When the water supply type is Class I, if the real-time turbidity value is ≤0.5NTU, a 16-bit PWM resolution is selected; if 0.5NTU < real-time turbidity value ≤1NTU, a 14-bit PWM resolution is selected; if the real-time turbidity value >1NTU, a 14-bit PWM resolution is selected and an alarm is triggered.
4. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, In step S4, the low-power steady light driver achieves current stabilization through the operational amplifier feedback unit in the constant current driver module. The operational amplifier feedback unit compares the control voltage output by the PWM converter unit with the sampled current of the light source module and dynamically adjusts the output current.
5. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, It also includes a temperature drift compensation step: real-time acquisition of the temperature of the light source module, and adjustment of the PWM signal duty cycle according to the preset temperature-luminous efficiency decay curve to compensate for luminous efficiency decay; Temperature acquisition is achieved through a temperature sensing element. The temperature and light efficiency decay curves are as follows: for every 5°C increase in temperature, the light efficiency decays by 3%. The main control module compensates for the light efficiency decay by increasing the PWM duty cycle by 3%.
6. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, It also includes a low-power standby step during the detection gap: during the two detection gaps, the constant current drive module is controlled to enter a low-power standby mode, the detection cycle is set to 1-3 seconds, and the detection time is 0.2-0.5 seconds. During non-detection gaps, the constant current drive module is controlled to switch to the lowest bit PWM resolution, and the PWM signal duty cycle is reduced so that the drive current of the light source module drops to below 5μA.
7. The method for detecting water turbidity with dynamically adjustable precision and low power consumption according to claim 1, characterized in that, In step S5, the turbidity exceedance threshold for the first type of water supply is 1 NTU, and the turbidity exceedance threshold for the second type of water supply is 3 NTU; the alarm method is audible and visual alarm, and the warning method is light warning or voice prompt.
8. A low-power, light-stabilized water turbidity detection device with dynamically adjustable precision, characterized in that, The method for performing a low-power steady-light water turbidity detection method with adjustable dynamic precision according to any one of claims 1-7 includes a main control module, a light source module, a constant current drive module, a temperature detection module, a turbidity detection module, a water supply type identification module, a water supply control module, and a power supply module. The light source module is used to emit a detection beam to illuminate the water sample; The turbidity detection module includes a measurement optical path and a reference optical path, which are used to collect optical signals and convert them into electrical signals for transmission to the main control module; The constant current drive module is connected between the main control module and the light source module, and includes a PWM converter unit, an operational amplifier feedback unit, a resolution switching unit, and a bandwidth adjustment unit. The temperature detection module is positioned close to the light source module and is used to collect the real-time temperature of the light source module and transmit it to the main control module. The water supply type identification module is used to collect the identification signal of the water supply channel and transmit it to the main control module; The water supply control module is used to control the on / off state of the water supply channel according to the control signals from the main control module; The power supply module provides power to the main control module, light source module, constant current drive module, temperature detection module, turbidity detection module, water supply type identification module, and water supply control module. The main control module is connected to the light source module, constant current drive module, temperature detection module, turbidity detection module, water supply type identification module and water supply control module respectively. The main control module has built-in water supply type identification logic, PWM resolution range matching rules and temperature drift compensation curve.