Secondary water supply control system based on peak shaving water pump

Abstract

The application discloses a secondary water supply control system based on a peak-shaving water pump, which comprises a total water inlet valve, a peak-shaving water tank water inlet valve, a peak-shaving water tank, a peak-shaving water tank liquid level transmitter, an inlet pressure transmitter, a pressure boosting pump water inlet valve, a pressure boosting water pump, a peak-shaving water pump, a check valve, a system air pressure tank, a pipeline outlet pressure transmitter and a frequency conversion control system.When the inlet pressure is higher than a preset pressure boosting water supply pressure threshold value, the pressure boosting pump water inlet valve is opened and the pressure boosting water pump is started to carry out pressure boosting water supply.When the threshold value is lower, the pressure boosting pump water inlet valve is closed and the pressure boosting water pump is stopped, and the peak-shaving water pump is started to take water from the peak-shaving water tank to carry out water supply.The peak-shaving water tank water inlet valve is controlled according to the comparison result of the peak-shaving water tank liquid level and the valve opening and closing liquid levels, so that the water storage and water release adjustment of the peak-shaving water tank are realized.The operation frequency of the water pump is adjusted according to the deviation between the pipeline outlet pressure and the target pressure, so that the outlet pressure of the water supply pipe network is kept constant.The application realizes automatic, stable and energy-saving water supply.

Description

Technical Field

[0001] This application relates to the field of secondary water supply systems, and in particular to a secondary water supply control system based on a peak-shaving water pump. Background Technology

[0002] With the rapid development of urbanization, people's demand for domestic water is constantly increasing. Due to uneven spatial and temporal distribution, complex water supply terrain, and large fluctuations in water usage, conventional secondary water supply systems often fail to maintain constant water pressure at the end of the water supply network, especially at the end of the municipal network or in villages far from water treatment plants. During off-peak hours, water supply is sufficient and water pressure is relatively stable in these areas. However, during peak hours, the outlet pressure of the water treatment plant remains constant. While the pressure fluctuation is smaller closer to the water treatment plant, the water pressure in these areas is still significantly insufficient, resulting in unstable water supply and difficulty for users to achieve comfortable water usage. To solve these problems, this invention adopts a new technical solution. Summary of the Invention

[0003] The purpose of this application is to provide a secondary water supply control system based on a peak-shaving water pump, which aims to solve the problems of insufficient water pressure and unstable water supply in the prior art.

[0004] In a first aspect, this application provides a secondary water supply control system based on a peak-shaving water pump. The system includes a main inlet valve, a peak-shaving water tank inlet valve, a peak-shaving water tank, a peak-shaving water tank level transmitter, an inlet pressure transmitter, a booster pump inlet valve, a booster pump, a peak-shaving water pump, a check valve, a system pressure tank, a pipeline outlet pressure transmitter, and a frequency conversion control system. The main inlet valve is located at the main inlet downstream of the municipal water network, and the booster pump receives water through the booster pump. The valve is connected to the municipal pipeline network. The peak-shaving water tank is connected to the municipal pipeline network through the peak-shaving water tank inlet valve and its outlet is connected to the peak-shaving water pump. The outlets of the booster pump and the peak-shaving water pump merge and are connected to the water supply network through the check valve and the system pressure tank. The inlet pressure transmitter, the pipeline outlet pressure transmitter and the peak-shaving water tank level transmitter are used to detect the inlet pressure, the outlet pressure and the peak-shaving water tank level, respectively. The frequency conversion control system is electrically connected to each water pump, electric valve and transmitter. When the inlet pressure is higher than the preset pressure threshold for superimposed water supply, the frequency conversion control system opens the inlet valve of the superimposed pump and starts the superimposed water pump to supply water. When the inlet pressure is lower than the preset pressure threshold for superimposed water supply, the frequency conversion control system closes the inlet valve of the superimposed pump and stops the superimposed water pump, and starts the peak-shaving water pump to draw water from the peak-shaving water tank for water supply. The opening and closing of the peak-shaving water tank inlet valve are controlled based on the comparison results between the peak-shaving water tank level and the valve-opening and valve-closing levels to achieve water storage and release regulation of the peak-shaving water tank; when the peak-shaving water tank level is lower than the valve-opening level, the peak-shaving water tank inlet valve is opened to store water, and when the peak-shaving water tank level is higher than the valve-closing level, the peak-shaving water tank inlet valve is closed to release water. Based on the deviation between the outlet pressure of the pipeline and the target pressure, the operating frequency of the booster pump or peak-shaving pump is adjusted by the frequency conversion control system to keep the outlet pressure of the water supply network constant.

[0005] In a preferred embodiment, the system further includes a dosing system connected to the main inlet, which is used to monitor the water quality at the main inlet in real time and automatically activate based on the water quality monitoring results.

[0006] In a preferred embodiment, the frequency conversion control system includes first to seventh circuit breakers, first to fourth frequency converters, first to sixth AC contactors, first to fourteenth intermediate relays, manual / automatic transfer switch, and programmable controller, wherein: The superimposed pump and the peak-shaving pump are respectively connected to the power input terminals of the first to fourth frequency converters through the corresponding first to fourth circuit breakers. The output terminals of the first to fourth frequency converters are respectively connected to the corresponding pump motors to control the start and stop and speed regulation of the corresponding pumps. The main inlet valve, the peak-shaving water tank inlet valve, and the booster pump inlet valve are respectively connected to the power supply circuit through the corresponding fifth to seventh circuit breakers and the first to sixth AC contactors. The forward and reverse control circuits of the first to sixth AC contactors are respectively controlled by the fifth to tenth intermediate relays to realize the opening and closing of each inlet valve. The manual / automatic switch is used to switch between manual control mode and automatic control mode. When in automatic control mode, the programmable controller outputs control signals to drive the first to fourth intermediate relays to start the corresponding water pumps by controlling the first to fourth frequency converters. The fifth to tenth intermediate relays drive the first to sixth AC contactors to control the opening and closing of each water inlet valve. The programmable controller is connected to the first to fourth frequency converters through a communication interface to acquire water pump operating status signals and fault status signals, and to control the corresponding water pumps to be put into operation or cut off according to the signals. The first to fourth frequency converters are equipped with operation output terminals and fault output terminals, which are used to feed back the water pump operation status signal and fault status signal to the programmable controller, respectively. Each inlet valve is equipped with an open position feedback signal and a closed position feedback signal, and the logic is judged by a programmable controller to realize the interlocking control of the opening and closing of each inlet valve.

[0007] In a preferred embodiment, the system further includes first to tenth manual control switches. When in manual control mode, the first to fourth intermediate relays are activated by the first to fourth manual control switches to control the first to fourth frequency converters to start the corresponding water pumps. The first, third, and fifth AC contactors are controlled by the fifth, seventh, and ninth manual control switches to control the opening of each inlet valve. The second, fourth, and sixth AC contactors are controlled by the sixth, eighth, and tenth manual control switches to control the closing of each inlet valve.

[0008] In a preferred embodiment, a pump room flooding probe is also included. When the pump room flooding probe detects a flooding signal, it is activated by the normally open contact of the thirteenth intermediate relay and by the fourteenth intermediate relay to activate the drainage pump for drainage.

[0009] In a preferred embodiment, the system further includes an analog module for converting the analog signals collected by the inlet pressure transmitter, the pipeline outlet pressure transmitter, and the peak-shaving water tank level transmitter into digital signals and transmitting them to the programmable controller.

[0010] In a preferred embodiment, when the manual / automatic selector switch is switched to automatic control mode, the normally open contact of the eleventh intermediate relay is closed for automatic control.

[0011] In a preferred embodiment, when the manual / automatic selector switch is switched to manual control mode, the normally open contact of the twelfth intermediate relay is closed for manual control.

[0012] In a preferred embodiment, the system further includes a power module and a power indicator light, wherein the power module supplies power to the water supply control system and the power indicator light indicates whether the power is on.

[0013] In a preferred embodiment, a flashing buzzer is also included, which is activated by the programmable controller when the water level in the peak-shaving tank is lower than the valve-opening level or higher than the valve-closed level, or when the water pump malfunctions.

[0014] Compared with the prior art, this application has at least the following beneficial effects: (a) Significant energy-saving effect: Makes reasonable use of the existing municipal pressure, superimposed pressure water supply, and makes up the difference only; (b) High degree of automation: Various water supply modes are automatically controlled by the PLC intelligent control system without the need for manual intervention; (c) Stable water supply: Low-peak water storage and energy storage, peak-peak energy release and water supply, ensuring stable water pressure; (d) Reduced costs: The effective combination of booster pumping and peak-shaving water supply eliminates the need to rebuild water storage tanks; (e) Water quality is guaranteed: real-time water quality monitoring and a dosing system are always on standby to maintain fresh water supply and ensure water safety.

[0015] It should be understood that, within the scope of this invention, the above-described technical features of this invention and the technical features specifically described below (such as in the embodiments) can be combined with each other to form new or preferred technical solutions. Due to space limitations, they will not be described in detail here. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. It should be understood that the accompanying drawings described below are merely some implementation examples of the present invention, and those skilled in the art can obtain other implementation examples based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application.

[0018] Figure 2 This is an electrical schematic diagram of each frequency converter in a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application.

[0019] Figure 3 This is an electrical schematic diagram of each inlet valve of a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application.

[0020] Figure 4 This is an electrical schematic diagram of the control loop of a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application.

[0021] Figure 5 This is an electrical schematic diagram of a programmable controller for a secondary water supply control system based on a peak-shaving water pump, according to one embodiment of this application.

[0022] Figure 6 This is an electrical schematic diagram of the analog input / output module of a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application.

[0023] Figure 7 This is a flowchart of a secondary water supply control system based on a peak-shaving water pump according to one embodiment of this application. Detailed Implementation

[0024] In the following description, many technical details are presented to help the reader better understand this application. However, those skilled in the art will understand that the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0026] The embodiments of this application relate to a secondary water supply control system based on a peak-shaving water pump, the structure of which is as follows: Figure 1 As shown, the system includes a main inlet valve 3, a peak-shaving water tank inlet valve 4, a peak-shaving water tank 5, a peak-shaving water tank level transmitter 6, an inlet pressure transmitter 7, a booster pump inlet valve 8, a booster pump 9, a peak-shaving pump 10, a check valve 11, a system pressure tank 12, a pipeline outlet pressure transmitter 13, and a frequency conversion control system (or frequency conversion control cabinet) 14. In this embodiment, the booster pump 9 and the peak-shaving pump 10 can each include multiple pumps; the figure illustrates two pumps as examples.

[0027] The main inlet valve 3 is located at the main inlet downstream of the municipal pipeline network. The booster pump 9 is connected to the municipal pipeline network through the booster pump inlet valve 8. The peak-shaving water tank 5 is connected to the municipal pipeline network through the peak-shaving water tank inlet valve 4, and its outlet is connected to the peak-shaving water pump 10. After the outlets of the booster pump 9 and the peak-shaving water pump 10 merge, they are connected to the water supply network through the check valve 11 and the system pressure tank 12. The inlet pressure transmitter 7, the pipeline outlet pressure transmitter 13, and the peak-shaving water tank level transmitter 6 are used to detect the inlet pressure of the municipal pipeline network, the outlet pressure of the water supply network, and the level of the peak-shaving water tank, respectively. The frequency conversion control system is electrically connected to each pump, electric valve, and transmitter.

[0028] When the inlet pressure is higher than the preset pressure threshold for booster water supply, the frequency converter control system opens the booster pump inlet valve 8 and starts the booster pump 9 to supply booster water. When the inlet pressure is lower than the preset pressure threshold for booster water supply, the frequency converter control system closes the booster pump inlet valve 8 and stops the booster pump 9, and starts the peak-shaving pump 10 to draw water from the peak-shaving water tank 5 for water supply.

[0029] The opening and closing of the peak-shaving water tank inlet valve 4 are controlled based on the comparison results between the peak-shaving water tank level and the valve-opening and valve-closing levels to regulate the water storage and release of the peak-shaving water tank 5. Specifically, when the peak-shaving water tank level is lower than the valve-opening level, the peak-shaving water tank inlet valve 4 is opened to store water; when the peak-shaving water tank level is higher than the valve-closing level, the peak-shaving water tank inlet valve 4 is closed to release water.

[0030] Based on the deviation between the pipeline outlet pressure and the target pressure, the operating frequency of the booster pump 9 or the peak-shaving pump 10 is adjusted by the frequency conversion control system to keep the outlet pressure of the water supply network constant.

[0031] The secondary water supply control system also includes a chemical dosing system 15, which is connected to the main water inlet. The chemical dosing system 15 monitors the water quality at the main water inlet in real time, and automatically activates when an abnormal water quality is detected to maintain water cleanliness.

[0032] The frequency converter control system includes a first circuit breaker QF10, a second circuit breaker QF11, a third circuit breaker QF12, a fourth circuit breaker QF13, a fifth circuit breaker QF14, a sixth circuit breaker QF15, a seventh circuit breaker QF16, a first frequency converter VVVF1, a second frequency converter VVVF2, a third frequency converter VVVF3, a fourth frequency converter VVVF4, a first AC contactor KM1, a second AC contactor KM2, a third AC contactor KM3, a fourth AC contactor KM4, a fifth AC contactor KM5, and a sixth AC contactor... Contactor KM6, first intermediate relay KA1, second intermediate relay KA2, third intermediate relay KA3, fourth intermediate relay KA4, fifth intermediate relay KA5, sixth intermediate relay KA6, seventh intermediate relay KA7, eighth intermediate relay KA8, ninth intermediate relay KA9, tenth intermediate relay KA10, eleventh intermediate relay KA11, twelfth intermediate relay KA12, thirteenth intermediate relay KA13, fourteenth intermediate relay KA14, and programmable logic controller (PLC).

[0033] refer to Figure 2 As shown, the booster pump 9 and the peak-shaving pump 10 are respectively connected to the power input terminals of the first circuit breaker QF10, the second circuit breaker QF11, the third circuit breaker QF12, and the fourth circuit breaker QF13, and the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4. The output terminals of the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4 are respectively connected to the corresponding pump motors to control the start and stop and speed regulation of the corresponding pumps. Specifically, the two booster pumps 9 are connected to the power input terminals of the first frequency converter VVVF1 and the second frequency converter VVVF2 respectively through the corresponding first circuit breaker QF10 and second circuit breaker QF11. The output terminals of the first frequency converter VVVF1 and the second frequency converter VVVF2 are respectively connected to the pump motors of the two booster pumps 9. The two peak-shaving pumps 10 are connected to the power input terminals of the third frequency converter VVVF3 and the fourth frequency converter VVVF4 respectively through the corresponding third circuit breaker QF12 and fourth circuit breaker QF13. The output terminals of the third frequency converter VVVF3 and the fourth frequency converter VVVF4 are respectively connected to the pump motors of the two peak-shaving pumps 10.

[0034] refer to Figure 3As shown, the main inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8 are connected to the power supply through the corresponding fifth circuit breaker QF14, sixth circuit breaker QF15, and seventh circuit breaker QF16, respectively. The opening contacts of the main inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8 are connected to the power supply circuit through the first AC contactor KM1, the third AC contactor KM3, and the fifth AC contactor KM5, respectively, to realize the opening of each inlet valve. The closing contacts are connected to the power supply circuit through the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6, respectively, to realize the closing of each inlet valve.

[0035] refer to Figure 4 As shown, the frequency converter control system includes a manual / automatic selector switch SA1 and first to tenth manual control switches SA2~SA11. The manual / automatic selector switch SA1 is used to switch between manual control mode and automatic control mode. When in automatic control mode, the programmable logic controller (PLC) outputs control signals to drive the first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, and the fourth intermediate relay KA4 to control the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4 to start the corresponding water pumps. The fifth intermediate relay KA5, the seventh intermediate relay KA7, and the ninth intermediate relay KA9 drive the first AC contactor KM1, the third AC contactor KM3, and the fifth AC contactor KM5 to control the opening of each inlet valve. The sixth intermediate relay KA6, the eighth intermediate relay KA8, and the tenth intermediate relay KA10 drive the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6 to control the closing of each inlet valve. In manual control mode, the first manual control switch SA2, the second manual control switch SA3, the third manual control switch SA4, and the fourth manual control switch SA5 drive the first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, and the fourth intermediate relay KA4 to control the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4 to start the corresponding water pumps. The fifth manual control switch SA6, the seventh manual control switch SA8, and the ninth manual control switch SA10 control the first AC contactor KM1, the third AC contactor KM3, and the fifth AC contactor KM5 to control the opening of each water inlet valve. The sixth manual control switch SA7, the eighth manual control switch SA9, and the tenth manual control switch SA11 control the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6 to control the closing of each water inlet valve.

[0036] In one embodiment, the frequency conversion control system further includes a pump room flood probe. When the pump room flood probe detects a flooding signal, it connects through the normally open contact of the thirteenth intermediate relay KA13 and connects the drainage pump through the fourteenth intermediate relay KA14 to drain water.

[0037] To better understand the technical solution of this application, a specific example is provided below. The details listed in this example are mainly for ease of understanding and are not intended to limit the scope of protection of this application.

[0038] To address the shortcomings of the aforementioned background technology, this invention proposes a secondary water supply control system based on peak-shaving pumps. The system comprises N superimposed pumps, N peak-shaving pumps, N frequency converters, a peak-shaving water tank, and a field data acquisition unit. This invention is primarily illustrated using an example of peak-shaving water supply achieved through two superimposed pumps (one in use and one on standby) and two peak-shaving pumps (one in use and one on standby).

[0039] Appendix Figure 2 The first circuit breaker QF10, the second circuit breaker QF11, the third circuit breaker QF12, and the fourth circuit breaker QF13 are respectively connected to the power input terminals of the first frequency converter VVVF1 corresponding to the #1 booster pump, the second frequency converter VVVF2 corresponding to the #2 booster pump, the third frequency converter VVVF3 corresponding to the #1 peak-shaving pump, and the fourth frequency converter VVVF4 corresponding to the #2 peak-shaving pump, and are responsible for connecting and disconnecting the power circuits of each frequency converter. The output terminals of the first frequency converter VVVF1 and the second frequency converter VVVF2 are respectively connected to the booster pump motors M1 and M2, and the output terminals of the third frequency converter VVVF3 and the fourth frequency converter VVVF4 are respectively connected to the peak-shaving pump motors M3 and M4. The frequency converters are mainly responsible for controlling the start and stop of the pumps and adjusting the speed of the motors.

[0040] Appendix Figure 3 The fifth circuit breaker QF14, the sixth circuit breaker QF15, and the seventh circuit breaker QF16 are responsible for connecting and disconnecting the power supply circuits of the main water inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8, respectively. The main contacts of the first AC contactor KM1, the third AC contactor KM3, and the fifth AC contactor KM5 control the energizing and de-energizing functions of the main water inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8, respectively. The main contacts of the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6 control the energizing and de-energizing functions of the main water inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8, respectively.

[0041] Appendix Figure 4The intermediate fuse FU1 is used for overcurrent and short-circuit protection of the control circuit; the manual / automatic selector switch SA1 is a manual / automatic control selection switch. When the manual / automatic selector switch SA1 is in the manual position, the coil of the twelfth intermediate relay KA12 is energized and the normally open contact is closed. At this time, the auxiliary control circuit can be controlled by the first manual control switch SA2, the second manual control switch SA3, the third manual control switch SA4, and the fourth manual control switch SA5 respectively. Figure 5 The coils of the first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, and the fourth intermediate relay KA4 are energized, and the normally open contacts of the corresponding intermediate relays are closed to control the start of the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4, thereby controlling the start of the water pump. The fifth manual control switch SA6, the seventh manual control switch SA8, and the ninth manual control switch SA10 control the coils of the first AC contactor KM1, the third AC contactor KM3, and the fifth AC contactor KM5 to open the main water inlet valve 3, the peak water tank inlet valve 4, and the booster pump inlet valve 8. The sixth manual control switch SA7, the eighth manual control switch SA9, and the tenth manual control switch SA11 control the coils of the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6 to close the main water inlet valve 3, the peak water tank inlet valve 4, and the booster pump inlet valve 8.

[0042] When the manual / automatic selector switch SA1 is in automatic mode, the coil of the eleventh intermediate relay KA11 is energized and connected, and the normally open contact closes. At this time, it can be connected via the attached... Figure 5 The programmable logic controller (PLC) automatically controls the coils of the first intermediate relay KA1, second intermediate relay KA2, third intermediate relay KA3, and fourth intermediate relay KA4 to close the normally open contacts of the corresponding intermediate relays, thereby controlling the start of the first frequency converter VVVF1, second frequency converter VVVF2, third frequency converter VVVF3, and fourth frequency converter VVVF4 to achieve the water pump operation and water supply function. It also controls the coils of the fifth intermediate relay KA5, seventh intermediate relay KA7, and ninth intermediate relay KA9 to close the normally open contacts of the corresponding intermediate relays, thereby controlling the coils of the first AC contactor KM1, third AC contactor KM3, and fifth AC contactor KM5 to achieve the valve opening function of the main water inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8, or via an auxiliary... Figure 5The programmable logic controller (PLC) automatically controls the coils of the sixth intermediate relay KA6, the eighth intermediate relay KA8, and the tenth intermediate relay KA10 to close their normally open contacts, thereby controlling the coils of the second AC contactor KM2, the fourth AC contactor KM4, and the sixth AC contactor KM6 to achieve the valve closing function of the main water inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8. The normally closed contact of the eleventh intermediate relay KA11 is a manual / automatic switching interlock contact used to prevent malfunction.

[0043] The power indicator HL1 indicates the power supply to the control circuit; it illuminates when the control circuit is powered and turns off when power is depleted. The normally closed contacts of the first AC contactor KM1, second AC contactor KM2, third AC contactor KM3, fourth AC contactor KM4, fifth AC contactor KM5, and sixth AC contactor KM6 are interlock contacts for the forward and reverse rotation of the corresponding valves, preventing mechanical failures or personal injury accidents caused by malfunctions. Limit switches STC, SLC, STO, and SLO are internal limit switches for the corresponding valves, protecting them from over-adjustment and damage to their mechanical components. The switching power supply S converts AC 220V to DC 24V to power the water immersion detector, pipeline outlet pressure transmitter 13, inlet pressure transmitter 7, peak-shaving water tank level transmitter 6, touchscreen HMI, and analog module EM AM06. The thirteenth intermediate relay KA13 is the feedback relay for the pump room water immersion probe; it activates when the probe detects a water immersion signal in the pump room. Figure 4 When terminals X2-1 and X2-2 are connected, the coil of the thirteenth intermediate relay KA13 is energized, and the corresponding normally open contacts are closed. At this time, the attached... Figure 5 The programmable logic controller (PLC) automatically controls the 14th intermediate relay KA14 to activate the drainage pump for emergency drainage while simultaneously closing the main inlet valve 3 to prevent flooding of the pump room; this continues until the flood probe signal disappears. Figure 5 The programmable logic controller (PLC) automatically stops the drainage pump and opens the main water inlet valve 3 to restore normal water supply.

[0044] Appendix Figure 5The programmable logic controller (PLC) in the system serves as the central brain of the entire water supply system, automatically implementing functions such as booster pumping, peak-shaving, water tank replenishment and energy storage, water quality assurance, and flood protection. Fuse FU1 provides power to the PLC and also offers overcurrent and short-circuit protection. The touchscreen HMI is the display and setting unit for the control system. It collects and displays parameters such as pump status, valve status, outlet pressure, inlet pressure, water tank level, pump motor frequency, current, and voltage. Users can also set parameters such as pump frequency, pump deceleration frequency, sleep frequency, pump delay, pump deceleration delay, sleep delay, rotation time, valve open level, and valve close level through the HMI. KA1~KA14 are the coils of the first to fourteenth intermediate relays, whose functions are described in the appendix above. Figure 4 The description is as follows, and will not be repeated here. The flashing buzzer HL2 is a fault alarm indicator. When the PLC detects a fault in the control system, such as a water pump malfunction, low water level, high water level, or flooding signal, the flashing buzzer HL2 will activate. After HL2 is powered on, it will flash and emit a buzzing alarm sound to remind personnel to check and repair the faulty equipment in a timely manner. RO1C and RO1B are the control output terminals for the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4. They are defined as operating outputs. RO1C and RO1B automatically connect when the frequency converter is running and automatically disconnect when the frequency converter stops, feeding back the switch signal to the PLC. RO2C and RO2B are the control output terminals for the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4. These are defined as fault outputs. When a frequency converter malfunctions, RO2C and RO2B automatically connect; when the frequency converter is functioning correctly, RO2C and RO2B automatically disconnect and feed back the switch signal to the PLC. The PLC automatically determines whether to activate or deactivate the corresponding water pump based on the operating / fault signal fed back from the frequency converter. OSL is the open-to-limit signal for the main inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8. When the valve opening limit is reached, OSL automatically connects; when the valve opening limit is not reached, OSL remains disconnected and feeds back its status to the PLC. CSL is the closed-end signal for the main inlet valve 3, the peak-shaving water tank inlet valve 4, and the booster pump inlet valve 8. When the valve reaches its closed limit, CSL is automatically activated; when the valve's closed limit is not reached, CSL remains deactivated and feeds its status back to the PLC. The PLC performs logical judgments on the received open and closed states, controlling the output of the valve switching relays to prevent excessive valve opening and closing, which could affect the valve's lifespan. The PLC can also use the valve opening and closing time to determine if there is a mechanical fault in the valve. The normally open contact of the thirteenth intermediate relay KA13 is the flood signal feedback point; it is activated when there is a flood signal and deactivated when there is no flood signal. Its function has been described in the appendix above. Figure 4As explained in the previous section, it will not be repeated here. The normally open contact of the eleventh intermediate relay KA11 is the automatic status feedback point. It is turned on when the manual / automatic selector switch SA1 is rotated to the automatic state, and turned off when the manual / automatic selector switch SA1 is rotated to the manual state. Its function has been described in the aforementioned appendix. Figure 4 As explained earlier, it will not be repeated here. A and B are the communication interfaces of the PLC, which are connected to the control terminals of each water pump frequency converter. The frequency converter PLC communicates with the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4 via MODBUS-RTU, and collects various parameters of the motor (motor frequency, operating voltage, operating current, etc.) in real time and displays them on the touch screen HMI.

[0045] Appendix Figure 6 The AM06 analog input / output module in the system converts the 4~20mA analog signals collected by the pipeline outlet pressure transmitter, inlet pressure transmitter, and water tank level transmitter into digital signals and transmits them to the auxiliary components. Figure 5 The programmable logic controller (PLC) in the system automatically performs functions such as booster water supply, peak-shaving water supply, and water storage and energy release in the water tank based on the real-time pressure and liquid level signals collected by the analog input / output module AM06. The analog input / output module AM06 can also convert the output signal calculated by the PLC's PID controller into 0~10V signals A5 and A6, which are input to the first frequency converter VVVF1, the second frequency converter VVVF2, the third frequency converter VVVF3, and the fourth frequency converter VVVF4. The frequency converters then automatically output corresponding frequency (0~50HZ) signals to the booster pump 9 and the peak-shaving pump 10 according to the magnitude of the input signal value, so as to adjust the pump speed and change the pump flow accordingly to maintain a constant outlet pressure.

[0046] The specific working principle of this system in actual operation is described in processes (a) to (e).

[0047] (a) The main inlet valve 3 is installed at the main inlet and is linked to the pump room water immersion probe. The main inlet valve 3 is normally in the open state to maintain the municipal water supply. When the water immersion probe detects a flooding signal, it indicates that there is a leak in the pump room or a pipe rupture, which poses a risk of flooding the pump room. At this time, the control system automatically closes the main inlet valve 3 to stop the water inflow and forces the drainage pump to start emergency drainage to protect the pump room equipment.

[0048] (b) The imported pressure transmitter 7 monitors the water supply pressure of the municipal water supply network in real time. When the inlet pressure meets the municipal booster water supply requirements (which can be set on the HMI, i.e., the corresponding preset booster water supply pressure threshold), the booster pump inlet valve 8 automatically opens, and the water supply system uses the municipal water pressure booster pump 9 to boost water supply, maintaining a constant pressure on the pipeline outlet pressure transmitter 13. When the inlet pressure is lower than the municipal booster water supply requirements (which can be set on the HMI), the booster pump inlet valve 8 will automatically close, and the control system will automatically switch the booster water supply mode to the peak-shaving water supply mode. The water supply system uses the peak-shaving water pump 10 to draw water from the peak-shaving water tank 5, maintaining a constant pressure on the pipeline outlet pressure transmitter 13.

[0049] (c) The peak-shaving water tank level transmitter 6 monitors the water level of the peak-shaving water tank 5 in real time. The peak-shaving water tank inlet valve 4 is controlled by the peak-shaving water tank level transmitter 6. When the water level in the tank is lower than the valve opening level (which can be set on the HMI), the control system automatically issues an opening command to open the peak-shaving water tank inlet valve and the water tank begins to replenish water and store energy. When the water level in the tank is higher than the valve closing level (which can be set on the HMI), the control system automatically issues a closing command to close the peak-shaving water tank inlet valve and the water tank stops replenishing water to prevent excessive replenishment and overflow that could flood the pump room.

[0050] (d) The dosing system 15 monitors the water quality at the main inlet in real time. When the water quality is abnormal, the dosing system will automatically start to maintain water quality safety and ensure water hygiene, and fully guarantee that the water source meets the national water quality and hygiene standards.

[0051] (e) The frequency converter control cabinet 14 monitors various parameters in the water supply system in real time (inlet pressure, outlet pressure, peak-shaving water tank level, pump status, valve status, pump frequency, pump current, etc.) and displays them on the touch screen. Simultaneously, the PLC in the control cabinet executes the above tasks according to a pre-programmed sequence to ensure stable water supply. For detailed workflow information, please refer to the appendix. Figure 7 As shown.

[0052] First, determine if the municipal water inlet pressure is low (i.e., the inlet pressure of the municipal pipe network does not meet the municipal booster pump's water supply requirements). If so, close the booster pump's inlet valve. Further determine if the outlet pressure is lower than the target pressure. If so, start the peak-shaving pump for peak-shaving replenishment until the outlet pressure is greater than or equal to the target pressure, then shut down the peak-shaving pump. If the municipal water inlet pressure is not low (i.e., the inlet pressure of the municipal pipe network meets the municipal booster pump's water supply requirements), open the booster pump's inlet valve. Further determine if the outlet pressure is lower than the target pressure. If so, start the booster pump for booster replenishment until the outlet pressure is greater than or equal to the target pressure, then shut down the booster pump. Simultaneously, determine if the peak-shaving water tank level is lower than the valve opening level. If so, open the tank replenishment valve for replenishment and energy storage until the peak-shaving water tank level is higher than the valve closing level, then close the tank replenishment valve. Second, monitor the water quality signals in real time for abnormalities. If abnormalities are detected, start the pressurization system to purify the water; otherwise, shut down the chemical dosing system. In addition, the water immersion probe is used to determine whether the water immersion signal is abnormal. If so, the main water inlet valve is closed until the water immersion signal returns to normal, at which point the main water inlet valve is opened.

[0053] The various technical features disclosed in the above-described invention, the various technical features disclosed in the following embodiments and examples, and the various technical features disclosed in the accompanying drawings can be freely combined to form various new technical solutions (all of which should be considered as having been recorded in this specification), unless such a combination of technical features is technically infeasible. For example, in one example, feature A+B+C is disclosed, and in another example, feature A+B+D+E is disclosed. Features C and D are equivalent technical means that serve the same function, and technically only one needs to be used; it is impossible to use both simultaneously. Feature E can be technically combined with feature C. Therefore, the solution A+B+C+D should not be considered as having been recorded because it is technically infeasible, while the solution A+B+C+E should be considered as having been recorded.

[0054] All references to this specification are considered to be incorporated integrally into the disclosure of this application so that they can serve as the basis for modifications if necessary. Furthermore, it should be understood that the above descriptions are merely preferred embodiments of this specification and are not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification should be included within the scope of protection of one or more embodiments of this specification.

Claims

1. A secondary water supply control system based on a peak-shaving water pump, characterized in that, The system includes a main inlet valve (3), a peak-shaving water tank inlet valve (4), a peak-shaving water tank (5), a peak-shaving water tank level transmitter (6), an inlet pressure transmitter (7), a booster pump inlet valve (8), a booster pump (9), a peak-shaving pump (10), a check valve (11), a system pressure tank (12), a pipeline outlet pressure transmitter (13), and a frequency conversion control system (14); wherein, the main inlet valve (3) is located at the main inlet downstream of the municipal pipeline network, and the booster pump (9) is connected to the municipal pipeline network through the booster pump inlet valve (8). The peak-shaving water tank (5) is connected to the municipal pipeline network through the peak-shaving water tank inlet valve (4) and its outlet is connected to the peak-shaving water pump (10). The outlets of the booster pump (9) and the peak-shaving water pump (10) are connected to the water supply network through the check valve (11) and the system pressure tank (12). The inlet pressure transmitter (7), the pipeline outlet pressure transmitter (13) and the peak-shaving water tank level transmitter (6) are used to detect the inlet pressure, outlet pressure and peak-shaving water tank level, respectively. The frequency conversion control system is electrically connected to each water pump, electric valve and transmitter. When the inlet pressure is higher than the preset pressure threshold for superimposed water supply, the frequency conversion control system opens the inlet valve (8) of the superimposed pump and starts the superimposed water pump (9) to supply water. When the inlet pressure is lower than the preset pressure threshold for superimposed water supply, the frequency conversion control system closes the inlet valve (8) of the superimposed pump and stops the superimposed water pump (9), and starts the peak-shaving water pump (10) to draw water from the peak-shaving water tank (5) for water supply. Meanwhile, the opening and closing of the peak-shaving water tank inlet valve (4) is controlled according to the comparison results of the peak-shaving water tank level with the valve opening level and the valve closing level. When the peak-shaving water tank level is lower than the valve opening level, the peak-shaving water tank inlet valve (4) is opened to store water. When the peak-shaving water tank level is higher than the valve closing level, the peak-shaving water tank inlet valve (4) is closed to release water. Based on the deviation between the outlet pressure and the target pressure, the operating frequency of the booster pump (9) or the peak-shaving pump (10) is adjusted by the frequency conversion control system to keep the outlet pressure of the water supply network constant.

2. The system as described in claim 1, characterized in that, The system also includes a dosing system (15), which is connected to the main water inlet and is used to detect the water quality at the main water inlet in real time and automatically start according to the detection results of the water quality.

3. The system as described in claim 1, characterized in that, The frequency conversion control system includes circuit breakers (QF10~QF16) from the first to the seventh, frequency converters (VVVF1~VVVF4) from the first to the fourth, AC contactors (KM1~KM6) from the first to the sixth, intermediate relays (KA1~KA14) from the first to the fourteenth, a manual / automatic transfer switch (SA1), and a programmable controller, wherein: The superimposed pump and the peak-shaving pump are respectively connected to the power input terminals of the first to fourth frequency converters (VVVF1 to VVVF4) through the corresponding first to fourth circuit breakers (QF10~QF13). The output terminals of the first to fourth frequency converters (VVVF1~VVVF4) are respectively connected to the corresponding pump motors to control the start and stop and speed regulation of the corresponding pumps. The main inlet valve (3), the peak-shaving water tank inlet valve (4), and the booster pump inlet valve (8) are respectively connected to the power supply circuit through the corresponding fifth to seventh circuit breakers (QF14~QF16) and the first to sixth AC contactors (KM1~KM6). The forward and reverse control circuits of the first to sixth AC contactors (KM1~KM6) are respectively controlled by the fifth to tenth intermediate relays (KA5~KA10) to realize the opening and closing of each inlet valve. The manual / automatic selector switch (SA1) is used to switch between manual control mode and automatic control mode. When in automatic control mode, the programmable controller outputs control signals to drive the first to fourth intermediate relays (KA1~KA4) to operate, thereby controlling the first to fourth frequency converters (VVVF1~VVVF4) to start the corresponding water pumps. The fifth to tenth intermediate relays (KA5~KA10) drive the first to sixth AC contactors (KM1~KM6) to control the opening and closing of each water inlet valve. The programmable controller is connected to the first to fourth frequency converters (VVVF1~VVVF4) through a communication interface to acquire water pump operating status signals and fault status signals, and to control the corresponding water pumps to be put into operation or cut off according to the signals. The first to fourth frequency converters (VVVF1~VVVF4) are equipped with operation output terminals and fault output terminals, which are used to feed back the water pump operation status signal and fault status signal to the programmable controller, respectively. Each inlet valve is equipped with an open position feedback signal and a closed position feedback signal, and the logic is judged by a programmable controller to realize the interlocking control of the opening and closing of each inlet valve.

4. The system as described in claim 3, characterized in that, It also includes the first to tenth manual control switches (SA2~SA11). When in manual control mode, the first to fourth intermediate relays (KA1~KA4) are driven by the first to fourth manual control switches (SA2~SA5) to control the first to fourth frequency converters (VVVF1~VVVF4) to start the corresponding water pumps. The first, third and fifth AC contactors (KM1, KM3, KM5) are controlled by the fifth, seventh and ninth manual control switches (SA6, SA8, SA10) to control the opening of each water inlet valve. The second, fourth and sixth AC contactors (KM2, KM4, KM6) are controlled by the sixth, eighth and tenth manual control switches (SA7, SA9, SA11) to control the closing of each water inlet valve.

5. The system as described in claim 3, characterized in that, It also includes a pump room flood probe. When the pump room flood probe detects a flooding signal, it connects through the normally open contact of the thirteenth intermediate relay (KA13) and connects the drainage pump through the fourteenth intermediate relay (KA14) to drain water.

6. The system as described in claim 3, characterized in that, Also includes: The analog signal module is used to convert the analog signals collected by the inlet pressure transmitter (7), the pipeline outlet pressure transmitter (13) and the peak-shaving water tank level transmitter (6) into digital signals and transmit them to the programmable controller.

7. The system as described in claim 3, characterized in that, When the manual / automatic selector switch (SA1) is switched to automatic control mode, the normally open contact of the eleventh intermediate relay (KA11) is closed to perform automatic control.

8. The system as described in claim 3, characterized in that, When the manual / automatic selector switch (SA1) is switched to manual control mode, the normally open contact of the twelfth intermediate relay (KA12) is closed for manual control.

9. The system as described in claim 3, characterized in that, It also includes a power module and a power indicator (HL1), the power module supplying power to the water supply control system and the power indicator (HL1) indicating this power.

10. The system as described in claim 3, characterized in that, It also includes a flashing buzzer (HL2), which is used by the programmable controller to trigger an alarm when the water level in the peak-shaving tank is lower than the valve-opening level or higher than the valve-closed level, or when the water pump malfunctions.

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