阅读说明：本技术 一种多泵并联多变频同步调速供水控制系统及其控制方法 (Multi-pump parallel multi-frequency conversion synchronous speed regulation water supply control system and control method thereof ) 是由 陈楼升 李盼盼 赵海兵 于 2020-05-12 设计创作，主要内容包括：一种多泵并联多变频同步调速供水控制系统及其控制方法,涉及供水设备技术领域,解决了供水低效和不稳定的问题,包括预设数量的水泵、变频器、传感器、PLC、人机界面和工业级5G路由器,所述的预设数量的水泵通过多泵并联的方式连接在一起,单个水泵与对应的变频器相连接,所述的PLC与变频器相连接,控制水泵运行,所述的传感器与PLC相连接,所述的人机界面与PLC相连接,实现人机交互,所述的工业级5G路由器与人机界面相连接,设备管理员可以通过工业级5G路由器对系统进行远程控制；控制系统结构简单,故障率低,控制精准,无极调速,同步调频,高效节能,多泵并联,细分流量。(A multi-pump parallel multi-frequency conversion synchronous speed regulation water supply control system and a control method thereof relate to the technical field of water supply equipment and solve the problems of low efficiency and instability of water supply, and comprise a preset number of water pumps, frequency converters, sensors, a PLC (programmable logic controller), a human-computer interface and an industrial grade 5G router, wherein the preset number of water pumps are connected together in a multi-pump parallel mode, a single water pump is connected with the corresponding frequency converter, the PLC is connected with the frequency converters to control the operation of the water pumps, the sensors are connected with the PLC, the human-computer interface is connected with the PLC to realize human-computer interaction, the industrial grade 5G router is connected with the human-computer interface, and an equipment administrator can remotely control the system through the industrial grade 5G router; the control system has the advantages of simple structure, low failure rate, accurate control, stepless speed regulation, synchronous frequency modulation, high efficiency, energy conservation, parallel connection of multiple pumps and flow subdivision.)

1. The utility model provides a many frequency conversion synchronous speed governing water supply control system that many pumps are parallelly connected, includes water pump, converter, sensor, PLC, human-computer interface and the industrial grade 5G router of predetermineeing quantity, characterized by the water pump of predetermineeing quantity link together through the parallelly connected mode of many pumps, single water pump is connected with the converter that corresponds, PLC be connected with the converter, the sensor be connected with PLC, human-computer interface be connected with PLC, industrial grade 5G router be connected with human-computer interface.

2. A control method for the multi-pump parallel multi-frequency conversion synchronous speed regulation water supply control system of claim 1, which is characterized by comprising the following steps:

firstly, after a system is started, firstly executing an initialization program, then collecting state information and analog quantity data of related components by a PLC (programmable logic controller), judging whether the system has a starting condition at present through operation and analysis, if all the conditions are normal, waiting for a starting command, and if the state or the data exceeds an alarm limit, sending alarm information;

secondly, after receiving a starting command, the system starts to operate, calls a special water supply PID subprogram, adjusts frequency output in real time according to a set value and a feedback value, and controls the fluctuation range of the outlet water pressure within 0.01 MPa;

thirdly, if the number of the water pumps which are put into operation at present cannot meet the total flow demand of a user end, the system increases the number of the water pumps and synchronously adjusts the speed, the pump increasing process is divided into two stages, the first stage is a quick response stage, the purpose is to quickly reach the effective rotating speed, and the system can start an anti-overshoot mechanism at the stage, so that the water pressure impact caused by the over-quick acceleration of the newly added pump is avoided; the second stage is a reestablishment balance stage, after the rotating speed of the newly-added pump reaches the effective rotating speed, the acceleration is properly slowed down, the rotating speed of the previously-operated water pump is properly reduced, and finally the newly-added pump and the previously-operated water pump reach a new balance point, so that multi-frequency-change synchronous speed regulation is realized; in the synchronous speed regulation stage, the system balances the working efficiency of each pump, and the actual working point of each pump is as close as possible to or reaches the highest point of efficiency, so that the energy-saving effect of the system is obvious;

fourthly, if the number of the water pumps which are put into operation at present is too large and the water supply capacity is surplus, the system can automatically reduce the number of the water pumps which are operated; the pump reducing process is divided into two stages, a first stage system firstly adjusts the speed of a pump to be reduced to be lower than an effective rotating speed so that the pump to be reduced can keep a certain rotating speed but can not normally supply water, then increases the speed of the rest running pumps, runs for a period of time, enters a second stage if the water supply requirement can be met all the time in the period, stops the pump to be reduced, and restores to the synchronous speed regulation if the water supply requirement can not be met in the period; the first stage aims at reducing the speed of the water pump and recovering the water supply in a short time;

and fifthly, when the user side does not use water, the system automatically judges and enters a sleep mode, and three conditions are simultaneously met when the user side enters the sleep mode: setting the relevant sleep parameters correctly, enabling the sleep function to be in an activated state, enabling the water pressure of the system to meet a set value, and enabling the water pump to be in a low-frequency (frequency-adjustable) running state for a long time (time-adjustable); after the three conditions are met, the system firstly adjusts the rotating speed of the running pump to be below the effective rotating speed and runs for a period of time, during the period, if the system has no pressure loss, the system enters a sleep mode, the rotating speed is adjusted to be 0, all the water pumps stop running in the sleep mode, but the water pressure change can be monitored in real time, and if the pressure drop amplitude is detected to be large, the system returns to the adjusting mode again, and normal water supply is recovered.

3. The control method of claim 2, wherein in the third step of increasing the pump, each time the system increases the pump, the principle of stopping and starting the pump first is followed, that is, the pump which stops the operation earliest is selected as the new pump, so as to achieve the balance of the service life.

4. The control method according to claim 2, wherein in the fourth step of decreasing the pump, each time the pump is decreased, the principle of starting and stopping first is followed, that is, the pump which is started first is selected as the pump to be decreased, so as to balance the service life of the water pump.

Technical Field

The invention relates to the technical field of water supply equipment, in particular to a water supply control system.

Background

At present, the types of water supply equipment are more, common water tank type water supply equipment and tank type pressure-superposed water supply equipment exist in the market, and the equipment generally mainly comprises a water tank, a pump set, a pipeline and a valve. The pump package generally has 2-3 water pumps, drags the operation through a converter, and when equipment moves, adjusts the water pump rotational speed through the converter, satisfies user end water pressure balance and decides, if a water pump's flow is not enough, can start other power frequency water pumps in proper order and compensate the flow.

The water supply equipment has the advantages of low cost, simple control system design and low admission threshold, and is favored by many small companies. However, the disadvantages are also very significant, as follows:

1. conventional equipment only has a converter, can't accomplish to let every pump can both frequency modulation, and the substitute is to use the contactor to let the surplus water pump be in the power frequency operation.

2. The water demand of a user side is fast in change, the time-varying coefficient is high, the system is required to have enough reaction speed, the conventional equipment system is slow in reaction, unstable in regulation and large in pressure fluctuation, and the difference between the maximum value and the minimum value is 0.1MPa or even more.

3. Conventional equipment is when the increase and decrease operation of control water pump, and only a water pump is in the frequency conversion regulation state all the time, and all the other water pumps are the power frequency operation, consequently when the input of power frequency water pump and excision, can bring great water pressure fluctuation, also can produce great impact to the electric wire netting simultaneously.

4. Conventional equipment is when many pumps move simultaneously, because the actual operating point of power frequency water pump and frequency conversion water pump is different, lead to the water outlet flow of every water pump and lift can not balanced distribution, and then produce the inhibitory action of each other in the system is inside, especially the frequency conversion water pump receives the suppression of power frequency water pump more easily, the most audio-visual performance both is that 1+1< 2's phenomenon can appear in the water pump flow, parallelly connected water pump quantity is more, this kind of phenomenon is more obvious, this is also among a lot of water supply equipment, the parallelly connected quantity of water pump can not exceed 3 root causes.

5. Because the mutual inhibition effect in the system cannot be avoided, a large part of lift and flow of the system can be lost, the energy consumption of the system can be increased, the efficiency is reduced, the strategic targets of national energy conservation and emission reduction are not facilitated, and meanwhile, more operation cost, such as electric charge and maintenance charge, is borne by users.

Disclosure of Invention

In order to solve the problems, the invention provides a multi-pump parallel multi-frequency-conversion synchronous speed-regulating water supply control system, and provides a safe, efficient, energy-saving and stable water supply system. In order to achieve the purpose, the invention adopts the technical scheme that: the utility model provides a many parallelly connected frequency conversion synchronous speed governing water supply control system of many pumps, is including the water pump of predetermineeing quantity, converter, sensor, PLC, human-computer interface and industrial grade 5G router, the water pump of predetermineeing quantity link together through the parallelly connected mode of many pumps, single water pump is connected with the converter that corresponds, PLC be connected with the converter, control water pump operation, the sensor be connected with PLC, human-computer interface be connected with PLC, realize human-computer interaction, industrial grade 5G router be connected with human-computer interface, the equipment administrator can carry out remote control through industrial grade 5G router to the system.

A control method of a multi-pump parallel multi-frequency conversion synchronous speed regulation water supply control system comprises the following steps:

1) after the system is started, firstly executing an initialization program, then collecting state information and analog quantity data of related components by the PLC, judging whether the system has a starting condition at present through operation and analysis, if all the conditions are normal, waiting for a starting command, and if the state or the data exceed an alarm limit, sending alarm information;

2) after receiving a starting command, the system starts to operate, calls a special water supply PID subprogram, adjusts frequency output in real time according to a set value and a feedback value, and controls the fluctuation range of the outlet water pressure within 0.01 MPa;

3) if the number of the water pumps which are put into operation at present cannot meet the total flow demand of a user end, the system increases the number of the water pumps and synchronously adjusts the speed, the pump increasing process is divided into two stages, the first stage is a quick response stage, the purpose is to quickly reach the effective rotating speed, and the system can start an anti-overshoot mechanism at the stage to avoid water pressure impact caused by over-quick acceleration of a newly-added pump; the second stage is a reestablishment balance stage, after the rotating speed of the newly-added pump reaches the effective rotating speed, the acceleration is properly slowed down, the rotating speed of the previously-operated water pump is properly reduced, and finally the newly-added pump and the previously-operated water pump reach a new balance point, so that multi-frequency-change synchronous speed regulation is realized; in the synchronous speed regulation stage, the system balances the working efficiency of each pump, the actual working point of each pump is as close as possible to or reaches the highest efficiency point, the energy-saving effect of the system is obvious, and the system increases the pumps each time, the principle of stopping and starting at first is followed, namely, the pump which stops running at the earliest is selected as a newly-added pump, so that the service life is balanced;

4) if the number of the water pumps which are put into operation at present is too large and the water supply capacity is surplus, the system can automatically reduce the number of the water pumps which are operated; the pump reducing process is divided into two stages, a first stage system firstly adjusts the speed of a pump to be reduced to be lower than an effective rotating speed so that the pump to be reduced can keep a certain rotating speed but can not normally supply water, then increases the speed of the rest running pumps, runs for a period of time, enters a second stage if the water supply requirement can be met all the time in the period, stops the pump to be reduced, and restores to the synchronous speed regulation if the water supply requirement can not be met in the period; the main purpose of the first stage is to enable the water pump to decelerate and simultaneously have the capability of recovering water supply in a very short time, and each time of reducing the pump, the principle of starting and stopping firstly is followed, namely, the pump which is started firstly is selected as the pump to be reduced so as to balance the service life of the water pump;

5) when the user end does not use water, the system automatically judges and enters a sleep mode, and the three conditions are simultaneously met when the user end enters the sleep mode: the method comprises the steps that firstly, related sleep parameters are correctly set, a sleep function is in an activated state, the water pressure of a system meets a set value, a water pump is in a low-frequency (frequency-adjustable) running state for a long time (time-adjustable), after the three conditions are met, the system firstly adjusts the rotating speed of the running pump to be below an effective rotating speed and runs for a period of time, during the period, if the system has no pressure loss, the system enters a sleep mode, the rotating speed is adjusted to be 0, all the water pumps stop running in the sleep mode, but the water pressure change can be monitored in real time, and if a pressure drop amplitude is detected to be large, the system returns to the regulation mode again to recover normal water.

Compared with the prior art, the invention has the following beneficial effects:

1. the control system has simple structure and low failure rate.

In the traditional equipment, because one frequency converter needs to circularly control a plurality of water pumps, a large number of intermediate relays and alternating-current contactors are needed to finish various switching actions, each relay and contactor can be connected with a large number of main circuit wires and control circuit wires, the number of wiring points is large, and through statistics, each contactor has about 12 to 14 wiring points, and needs to be connected with 12 to 20 wires; each intermediate relay has about 8 to 14 connection points, and 8 to 18 wires need to be connected. Therefore, the problems of complex production process, long production period, more fault points, high fault rate and the like are caused.

The invention adopts the one-to-one control of the frequency converter, the output end of the frequency converter is directly connected with the water pump, the AC contactor is abandoned, and the using amount of the intermediate relay is greatly reduced, thereby simplifying the system structure, reducing the fault points, reducing the fault rate, simplifying the production process and shortening the production period.

2. Accurate control and stepless speed regulation.

The traditional equipment only has a converter, can only guarantee that one water pump is in the frequency modulation state, and the surplus water pump can only use the power frequency operation, and frequency gradient is obvious, and especially the frequency can appear scarp formula change when increasing the pump, subtracting the pump, cutting the pump, brings huge water pressure fluctuation, causes the impact to the electric wire netting simultaneously.

The invention can ensure that each water pump is in a variable frequency operation mode, has very good frequency regulation continuity and no gradient change, can realize stepless speed regulation, avoids water pressure fluctuation and power grid impact caused by actions of increasing the pump, reducing the pump, cutting the pump and the like, and can control the water pressure fluctuation of the three working conditions within 0.01MPa through experimental verification.

3. Synchronous frequency modulation, high efficiency and energy saving.

The traditional equipment has different water pump operation modes, the power frequency water pump works strongly, the inhibition effect on the variable frequency water pump is obvious, the serious internal consumption is caused, the water supply efficiency of the whole machine is low, and the very high energy consumption is further brought.

The invention can synchronously frequency-modulate each running water pump, namely the rotating speeds of the water pumps are equal, and the working points of each water pump are the same from the aspect of a performance curve, so that the water outlet flow and the lift of each water pump are completely the same, no strong pump or inferior pump exists, the internal consumption of the system is fundamentally avoided, the running efficiency is greatly improved, and the energy consumption of the whole machine is reduced. Experiments on the same type of equipment (the lift, the flow and the power are the same) prove that the energy-saving effect of the whole machine can reach 3 percent on average, and can reach 23.6 percent under special working conditions. (the testing method adopts QCQ3153 testing flow and method specified in the Secondary Water supply energy-saving certification Specification)

4. The multiple pumps are connected in parallel to subdivide the flow.

The internal consumption of a traditional equipment system is serious, the typical performance is that the total flow of the system after parallel connection has a phenomenon that 1+1 is less than 2, and the phenomenon is more obvious when the number of parallel pumps is more, so that the number of water pumps of the conventional equipment is generally not more than 3, the water pump model with larger single pump flow can be selected for the water environment with large total water flow and large time-varying coefficient, and when the water supply is carried out at a small flow, the operation of the water pump is seriously deviated from a high-efficiency point, so that the energy consumption is increased.

The invention eliminates the internal consumption of the system, thereby solving the problem of complaints, selecting a plurality of small-flow water pumps to be connected in parallel for the water environment with large total water flow and large time-varying coefficient, selecting 3-6 or more water pumps according to the actual situation, realizing flow subdivision, flexibly coping with various working conditions such as small flow, large flow and the like, ensuring that each water pump operates at a high-efficiency point, further reducing the energy consumption and saving the operation cost.

Drawings

The present invention is described in further detail below with reference to the attached drawings.

FIG. 1 is a schematic diagram of the control process of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described with reference to fig. 1 and the specific embodiments.

The utility model provides a many parallelly connected frequency conversion synchronous speed governing water supply control system of many pumps, is including the water pump of predetermineeing quantity, converter, sensor, PLC, human-computer interface and industrial grade 5G router, the water pump of predetermineeing quantity link together through the parallelly connected mode of many pumps, single water pump is connected with the converter that corresponds, PLC be connected with the converter, control water pump operation, the sensor be connected with PLC, human-computer interface be connected with PLC, realize human-computer interaction, industrial grade 5G router be connected with human-computer interface, the equipment administrator can carry out remote control through industrial grade 5G router to the system. Has the following characteristics:

1. the multiple pumps are connected in parallel, the water pump selects a product with a national secondary energy-saving authentication mark, the matching motor selects an ultrahigh-efficiency three-phase asynchronous motor, and the energy efficiency grade is not lower than IE 3.

2. Each water pump is provided with a high-efficiency energy-saving frequency converter, so that the number of the water pumps is equal to that of the frequency converters, and the system can realize one-to-one control.

3. A PLC (programmable logic controller) is used as a control core, system operation data is collected, calculation and analysis are carried out, a control instruction is sent out, and functions of unit control, data calculation, fault diagnosis, alarm prompt and the like are achieved.

4. The human-machine interface (HMI) realizes human-machine interaction, and comprises the functions of parameter setting and modification, state query, fault query, alarm record storage and the like.

5. The system supports the functions of remote control, remote parameter adjustment and the like, and the whole system can be connected with an equipment management platform through an industrial grade 5G router (the network modes such as 4G, 3G, 2G and the like are compatible downwards), so that the running state can be checked in real time, the running parameters can be called, and the program version can be updated.

As shown in the attached figure 1, the control method of the multi-pump parallel multi-frequency-conversion synchronous speed-regulation water supply control system comprises the following steps:

1) after the system is started, firstly executing an initialization program, then collecting state information and analog quantity data of related components by the PLC, judging whether the system has a starting condition at present through operation and analysis, if all the conditions are normal, waiting for a starting command, and if the state or the data exceed an alarm limit, sending alarm information;

2) the system starts to operate after receiving a starting command, calls a special water supply PID subprogram, adjusts frequency output in real time according to a set value and a feedback value, and controls the fluctuation range of the outlet water pressure within 0.01 MPa. Through algorithm optimization, the system is more stable in operation, and parameter setting is more convenient and fast;

3) if the number of the water pumps which are put into operation at present cannot meet the total flow demand of a user end, the system increases the number of the water pumps and synchronously adjusts the speed, the pump increasing process is divided into two stages, the first stage is a quick response stage, the purpose is to quickly reach the effective rotating speed, and the system can start an anti-overshoot mechanism at the stage to avoid water pressure impact caused by over-quick acceleration of a newly-added pump; the second stage is a reestablishment balance stage, after the rotating speed of the newly-added pump reaches the effective rotating speed, the acceleration is properly slowed down, the rotating speed of the previously-operated water pump is properly reduced, and finally the newly-added pump and the previously-operated water pump reach a new balance point, so that multi-frequency-change synchronous speed regulation is realized; in the synchronous speed regulation stage, the system balances the working efficiency of each pump, the actual working point of each pump is as close as possible to or reaches the highest efficiency point, the energy-saving effect of the system is obvious, and the system increases the pumps each time, the principle of stopping and starting at first is followed, namely, the pump which stops running at the earliest is selected as a newly-added pump, so that the service life is balanced;

4) if the number of the water pumps which are put into operation at present is too large and the water supply capacity is surplus, the system can automatically reduce the number of the water pumps which are operated; the pump reducing process is divided into two stages, a first stage system firstly adjusts the speed of a pump to be reduced to be lower than an effective rotating speed so that the pump to be reduced can keep a certain rotating speed but can not normally supply water, then increases the speed of the rest running pumps, runs for a period of time, enters a second stage if the water supply requirement can be met all the time in the period, stops the pump to be reduced, and restores to the synchronous speed regulation if the water supply requirement can not be met in the period; the main purpose of the first stage is to enable the water pump to decelerate and simultaneously have the capability of recovering water supply in a very short time, and each time of reducing the pump, the principle of starting and stopping firstly is followed, namely, the pump which is started firstly is selected as the pump to be reduced so as to balance the service life of the water pump;

5) when the user end does not use water, the system automatically judges and enters a sleep mode, and the three conditions are simultaneously met when the user end enters the sleep mode: the method comprises the steps that firstly, related sleep parameters are correctly set, a sleep function is in an activated state, the water pressure of a system meets a set value, a water pump is in a low-frequency (frequency-adjustable) running state for a long time (time-adjustable), after the three conditions are met, the system firstly adjusts the rotating speed of the running pump to be below an effective rotating speed and runs for a period of time, during the period, if the system has no pressure loss, the system enters a sleep mode, the rotating speed is adjusted to be 0, all the water pumps stop running in the sleep mode, but the water pressure change can be monitored in real time, and if a pressure drop amplitude is detected to be large, the system returns to the regulation mode again to recover normal water.

The system has perfect protection function, and when the conditions of overload, overcurrent, overvoltage, undervoltage, short circuit, phase failure, water shortage and the like occur, the system can automatically detect and make corresponding protection actions, such as automatic power off, shutdown and the like, so that the equipment can be protected from being damaged, the power grid can be protected from being impacted, and the pipeline can be protected from being damaged.

The system has the functions of self-checking the system state and diagnosing faults, and various faults occurring during the operation of the system can be recorded and stored through the HMI, and different solutions are automatically provided according to the fault types for reference of field maintenance personnel.

The working principle and the working process of the invention are as follows: the water supply system comprises a pump set pipeline system and a water supply control system, and the pump set pipeline system mainly completes the functions of storing and conveying water; the water supply control system mainly completes full-automatic control of the whole system, and various sensors and instruments such as a water inlet and outlet pressure transmitter, a pressure switch, a current transformer, a flowmeter, an electric energy quality monitor and the like feed various data of the system back to the control center PLC in real time, obtain a frequency value required to be output by the current system after a series of calculation and analysis, and then process the frequency value by a frequency converter in a bus communication mode to achieve the purpose of controlling the rotating speed of a water pump, and finally achieve the purpose of water pressure balance determination of a user side.

The control system automatically judges the water pressure change trend of the user side, adjusts the output frequency in real time, and when a plurality of water pumps run simultaneously, the system automatically calculates the optimal frequency combination, ensures that the rotating speeds of the running water pumps are equal, realizes synchronous frequency modulation, eliminates the internal consumption of the system, and realizes the purposes of saving energy and reducing consumption on the premise of meeting various water supply working conditions of the user side.

When the system runs, various data and equipment states are monitored in real time, alarm information is sent when data are abnormal or equipment faults occur, if the data are not fatal faults, the system automatically cuts off a fault unit and continues to maintain water supply, if the data are fatal faults, the system can make corresponding protection mechanisms such as automatic power off and automatic shutdown, and the like, and fault information is kept in the HMI to provide a corresponding solution for reference of field maintenance personnel.

The system is connected with the dispatching system through an industrial grade 5G router (downward compatible with 4G, 3G and 2G), and various operation data, equipment states, control commands and the like are sent to the dispatching system for a watchman to look up, and manual control can be intervened if necessary. The system supports remote operation and maintenance, can remotely monitor the running state of the PLC and update the PLC or HMI program version.

The technical solutions of the present invention or similar technical solutions designed by those skilled in the art based on the teachings of the technical solutions of the present invention are all within the scope of the present invention.