Product synopsis:

Since the 1980 s, frequency control of motor speed secondary water supply technology for its stable water supply pressure, health, energy-saving advantages of gradually replaced the pump water

Tower, water pump, the roof water tank and air pressure water supply water supply way, be the first choice of the second pressurized water supply scheme. Is controlled by programmable frequency conversion Water Supply Equipment

Unit, inverter, control circuit and pump unit constitute a closed-loop control system, the constant pressure of water supply pipe. The equipment has high efficiency and energy saving

High point, solve the traditional water tank water supply water pressure and the roof water tank top users of water quality of secondary water pollution problems, widely used in industrial and civil building

Building water supply system. The scope of its water supply from a building to building, dozens of building even extended to the village. By the single chip microcomputer frequency conversion control technology

PLC microcomputer control development to digital integrated full variable frequency control technology, thanks to the development of electronic technology, no matter from the effectiveness of control accuracy, control technology

Surface, or from the economy, energy saving ability has the very big development. Increasingly powerful computer functions, development and mature of frequency conversion technology, variable frequency constant

Pressure water supply is widely used in secondary water supply equipment, become the main force of secondary water supply technology.

Second, the microcomputer control of frequency conversion water supply

Microcomputer control frequency conversion water supply equipment is mainly composed of single-chip microcomputer and PLC microcomputer frequency conversion control cabinet (including the man-machine dialogue interface), supply

Water pumps, pressure sensor, liquid level sensor, pressure tank, valves and piping etc, then the configuration of the stainless steel water tank, then form the microcomputer

Control frequency conversion water supply pump station. Control of microcomputer principle and frequency conversion water supply system device object

Third, the working principle of microcomputer control frequency conversion water supply

The basic principle of variable frequency speed regulation technology is based on motor speed and power input frequency is proportional to the work (pictured)

The power frequency by changing the motor, you can achieve the goal of changing motor speed.

Inverter is integrated frequency conversion technology and microelectronic technology, by changing the way to control the motor power frequency ac motor power control equipment.

Microcomputer control frequency conversion water supply technology is the use of single chip microcomputer and programmable controller (PLC) as the main control unit, the inverter and the relay circuit for automatic control, change by the frequency converter power supply frequency control pump motor speed, motor to realize stepless speed regulation, make the pump rotation speed and flow rate can be adjusted. Task is to detect sensor network import and export pressure, the pressure setting unit provide can meet the needs of user expectations of hydraulic system. Pressure setting signal and feedback signal in the input after the PLC, the PLC internal PDI control program calculation, output a speed control signal to frequency converter.

1) at present, the microcomputer control variable frequency speed regulation technology of water supply according to its outlet pressure value is different, divided into two kinds of constant pressure and variable pressure variables.

(1) the constant pressure variable flow control mode:

Feed water pressure value to design a second set by the system you need for a water pump outlet ShuiGuanChu pressure. In the water pump outlet pipe installed on the electric contact pressure gauge and pressure sensors sampling, to set the pressure feedback actual value and system of feed water pressure value comparison, the difference is input into the CPU control unit after processing, sends out control instructions, control of electric pump

Put the Numbers and running of the machine speed variable pump motor, so as to achieve stable water supply pipe network pressure on the set pressure value.

(2) the variable voltage variable flow control mode:

Installed in the end of the water supply network sampling electric contact pressure gauge and pressure sensor, the feedback of pressure required at the end of the actual value and the water supply network water pressure value comparison, the difference between the input to the control unit of the CPU processing, sends out control instructions, control stations and pump motor was put into operation of variable pump motor speed, so that maintain a constant water pressure at the ends of pipe, and the water pump outlet pipe pressure with the change of water supply and change.

2) with variable voltage variable flow control mode there is a big difficulty, the implementation of the engineering practice in constant pressure variable control mode. Now with constant pressure variable control mode as an example, the principle of microcomputer control frequency conversion water supply technology:

(1) first of all, through the human-computer interaction interface, to the microcomputer PLC (programmable controller) to set the working pressure of feed water pump group, namely, the required pressure water users.

(2) when the water pressure sensors detect the pump outlet pressure group cannot satisfy the user the most unfavorable point with water pressure requirements needed, then feedback to the PLC programmable device, the programmable controller PLC internal PID control procedures, pressure signal and set according to the feedback signal comparison between calculation and output a speed control signal to frequency converter, the duty work water pump frequency conversion control, along with the increase of output frequency motor speed is accelerated,

(3) when the water pressure sensors detect equipment supply pressure to achieve system set pressure value, the motor speed, stable system to the initial balance, working pump is greater than the equipment in the minimum power frequency (25 hz or higher) state variable frequency operation; Increase as the system of water, water pressure sensors detect the outlet pressure once again can not meet the requirement of the user the most unfavorable point with water pressure required, the inverter output frequency continue to rise, motor speed is accelerated, equipment water flow rate increases, maintain a constant water pressure.

(4) when the system work flow more than the rated flow of pump working point, the targets set by the single pump operation can't maintain system pressure, pump on a second job. System according to the set procedures, will automatically switch to the first variable frequency operation of the pump running, power frequency and frequency converter automatically switches to the next stage pump starts, the device has reached the much work pump in parallel operation. So the order change, equipment in the condition of working frequency alternating operation.

(5) when water consumption system to reduce export pressure equipment, PLC programmed control frequency converter to reduce the frequency, the pump running speed down. When run down to the water pump minimum frequency, automatically reduce operational working pump sets, or out of work more

Pump in parallel inverter running state, back to a water pump rated flow within the scope of the variable frequency operation condition.

(5) a dormant state, when the system further reduce water consumption, minimum pressure demand below pump working frequency, which fell to sleep frequency preset (parameters), frequency converter to enter a dormant state, working pump stops, start small flow auxiliary pump (when the device configuration sometimes) or by air pressure tank water supply voltage supply at this time.

(6) equipment according to the set procedures to monitor water pressure sensor changes at any time, when the discharge pressure is lower than the system set by sensei pressure value (parameters preset, generally for the equipment export pressure setting of 90% ~ 95%), working pump restart operation and repeat the process.

Summarized as the principle of microcomputer control frequency conversion water supply is the use of system detection unit and micro processing unit, by changing the power frequency to reach the purpose of changing supply voltage, meet the actual needs of the supply pressure, thus achieve the goal of control of motor speed, constant pressure and energy saving.

Four, the features of microcomputer control frequency conversion water supply equipment

Microcomputer control frequency conversion water supply equipment of the main features are:

1) high intelligent degree

Control core programmable controller (PLC) set simple function of the computer and the flexibility and versatility, fast response, high precision, good stability, high reliability, compared with traditional single-chip computer and relay control system have the characteristics of long life and low failure rate, greatly improve the intelligent control function, ensure the long-term trouble-free operation system under complex conditions.

2) high efficiency and energy saving equipment

USES the frequency conversion technology, can according to need to set the pressure of water supply, inverter control of pipe network based on the actual water consumption to water pump speed, accurate configuration suitable output power, ensure the pump always run in high efficiency area.

3) the effect of constant pressure stability

System adopts PID closed-loop adjustment, using frequency conversion software, can avoid the current shock, direct response in supply pressure constant pressure control, pressure control precision up to 0.01 MPa, constant pressure to avoid the impact to equipment network, greatly extended the water pump, motor, and the service life of pipeline valves.

4) regularly in pump function

For many sets of water pump system, according to how to determine the pipe network water running pump sets, pumps more running cycle frequency conversion start-stop, equal job opportunities, to avoid a long-term running pumps and serious wear and tear, and other water pump for a long time don't use due to rust, prolong the service life of each pump effectively.

5) complete protection mechanism

With overload, short circuit, overvoltage, undervoltage, lack of phase, over current, short circuit, liquid level, dry, water immersion and various protective functions such as lightning fault alarm signal, in exceptional cases can self-check, fault diagnosis, etc.

6) can be a high degree of customization

PLC feature-rich, reliable operation, easy management, realize linkage with communication interface with other equipment, to facilitate the various parameters of the first computer, make run real-time remote monitoring, can also big data collection, analysis, help to improve equipment performance.

7) small flow pressure maintaining function

Water low hours, working pump out of operation, according to the set of program instruction configuration of equipment flow and auxiliary pump or air pressure tank instead of working pump auxiliary operation, which can effectively avoid the main pump work frequently, ensure smooth water supply system, decrease energy consumption of the machine running on the device and at the same time, the diaphragm pressure tank can buffer the water hammer pressure fluctuations.

8) favorable human-computer interaction interface

Big screen touch screen realization man-machine dialogue, parameter Settings window, flexibly and conveniently on the man-machine interface can set the working pressure, the cut-off frequency, frequency of dormancy, increase or decrease the pump parameters such as frequency, and all of the fault by the system for monitoring, control and record, can guide users to exclude accurately. In a word, the microcomputer control of frequency conversion water supply equipment is the largest

(the following chart is a guangzhou panyu zhongjian project construction site temporary water, USES the microcomputer control frequency conversion water supply equipment)

Five, the new type of digital integrated full variable frequency control water supply equipment introduction:

Microcomputer control core is the inverter frequency conversion water supply pump motor, according to the water pressure changes automatically adjust the water pump operation frequency, for motor speed feedback to the pump motor, so as to realize frequency conversion constant pressure water supply. Microcomputer control frequency conversion water supply equipment basic PLC (programmable controller) inverter ten relay circuit of electrical control cabinet to realize frequency control of motor speed and operation control of pumps, pump start to stop all need to relay the secondary control loop with mechanical contact switch, safety and reliability improvement; All pumps Shared a general-purpose inverter, through frequent alternation switching frequency converter to realize more pumps start-stop frequency conversion, and two or more pumps row can only achieve a pump frequency control of motor speed operation, other working pump power frequency operation, efficiency of pump is not common area operation, deviating from the efficiency of the phenomenon, energy saving effect is limited, and even more energy; Frequency conversion control and pumps are usually installed in the pump room, by the environmental factors such as humidity, condensation water, dust, etc on the equipment of electrical control, reason is used frequently, differ as a result of various kinds of applications at the same time, its control core PLC need according to the actual working condition requirements in terms of artificial quadratic programming, operation control requirements, in order to achieve standardization degree is not high, non-professional workers don't have the ability to operate and use not convenient. Digital integrated full variable frequency control technology of water supply, it is the secondary water supply field application of frequency control of motor speed in the variable frequency constant pressure water supply equipment and the latest achievements in the process of the control technology research and development, the technology will frequency control of motor speed, the PID (proportion, integral, differential) control technique and water pump operation control used by other functions integrated into an organic whole, integrates the water pump frequency control of motor speed and automatic control, through the application of large scale integrated circuit technology will each function module encapsulation in a level IP55 protection casing, and can directly with standard motor pump installation, also can be installed in the equipment of electrical control room. Digital integrated full variable frequency control water supply equipment independently configure each pumps in a special digital integrated water pump frequency conversion controller, not alone the other set of frequency conversion control cabinet, the frequency conversion controller through CAN bus technology to communicate with each other, linkage control and coordination, to achieve more working pump efficiency share balanced running, you CAN directly through the frequency conversion controller on the display screen man-machine dialogue to achieve pumps running all parameter setting and adjustment, do not need to be quadratic programming. Digital integrated full variable frequency control water supply equipment is safe and reliable, high efficiency and energy saving, convenient humanization characteristics significantly.

(1) digital integrated all the working principle of variable frequency control water supply equipment

Digital integrated full frequency conversion control constant pressure water supply equipment in each independent pumps fitted with a variable frequency speed regulation and control function of special digital integrated water pump frequency conversion controller. System through the outlet of the pressure sensor to detect the current outlet pressure value, to integrate the values and digital variable frequency controller of the system setting target value, to determine the variable frequency drive pump run the Numbers and operation frequency, when two or more working pump running at the same time, the system achieved by digital integrated frequency conversion controller inside the CAN bus communication each other, automatic allocation ratio operation, implement two or more pumps group run ratio is consistent, and according to the actual demand of increasing or decreasing, the system automatically for more than one pump synchronous rise or fall frequency, make sure the system run time in full variable frequency operation state, to avoid the pump running state and pump power frequency deviation efficiency area running phenomenon exists, to ensure the supply pressure is constant. On the contrary, when you don't need more pump parallel synchronous operation of the same frequency, the system automatically decrease, in turn, pump, until the machine into the downtime dormancy.

(2) the characteristics of digital integrated full variable frequency control water supply equipment

Digital integrated full variable frequency control water supply equipment, water supply technology from the perspective of control and frequency conversion system in the field of the latest innovations, each pumps in water supply equipment composed of the one-to-one configuration has a special frequency conversion controller independently, each pump frequency conversion controller through the CAN on the total line technique to communicate with each other, CAN automatically adjust the frequency conversion operation ratio according to the variation of water demand, realize the pumps run at the same time, synchronous equilibrium allocation, remain the state of variable frequency pump unit operation is achieved, avoid the water pump is not running efficiency area, stable water supply pressure, compared with the traditional frequency conversion water supply equipment to save energy. At the same time, due to the digital integrated in full variable frequency control pump group, 100% have a spare pump with frequency conversion control implementation, digital integrated frequency conversion controller is encapsulated within the IP55 protection grade of the shell, support for multiple sensor signal input, enhance the safety and reliability of water supply equipment. Its main technical characteristics are as follows:

1) integrated pump dedicated power circuit

Integrated water pump dedicated power circuit for semiconductor circuit, its core is IGBT power inverter, the IGBT power integrated circuit on a PCB printed circuit board. Dynamic power directly from the power circuit connection terminal input, through the power circuit of the inverter output to the pump motor. Integrated power circuit mainly for the realization of digital, standardization and generalization of water pump control circuit, makes the pump electrical control is no longer dependent on mechanical relay components, realize non-contact switch pump frequency conversion control, improve the work reliability.

IGBT integrated pump dedicated power circuit to achieve the secondary water supply pump frequency conversion driving circuit of digitization, miniaturization, standardization. To solve the secondary water supply equipment control components, control cabinet volume bigger problem. Solved the traditional secondary water supply equipment loop circuit is complex, use the relay contact switch pump run or stop the problem of high failure rate and safe hidden trouble more. Solve the frequent stops and components of the question of short life, semiconductor device instead of relay circuit, due to lower the probability of relay circuit fault stop pump water 80%.

2) integrated innovation application of PID controller

Digital circuit composed of CPU and memory cell, integrated into the PCB printed circuit boards. PID controller to the pump running involved in the various commands, such as parameter control program all standardized integration into and stored in PID controller. According to different water pump, water pump motor, power applications demand variable conditions, such as open P (proportional) by the controller, the I (integral), D (differential) parameter adjustment, meet the needs of the water pump frequency conversion operation control. Solve the standardization of the main control unit, no longer up programmable controller PLC, quadratic programming is no longer necessary.

Integrated PID controller to realize the secondary water supply equipment water pump control system control procedures of standardization and standardization of the controller. Solve the traditional frequency secondary water supply equipment need professional personnel according to the condition of application of different water supply equipment of quadratic programming, the problem of low degree of standardization. Whether tank overlying water supply equipment, box-type overlying water supply equipment, constant pressure frequency conversion water supply equipment, or hvac water circulating pump can free combination configuration. Solve the maintenance and repair or function extension relies on elv engineer change the problems of PLC control program, reduce the use of operating personnel's professional and technical requirements.

3) system modular (special pump frequency conversion controller)

Digital integrated special pump frequency conversion controller will power integrated circuits, integrated PID controller, such as heat dissipation, input and output terminal functional components designed in the form of the plug-in modules, each module in the form of the plug-in together, and encapsulated in a protective registration reach inside the shell of IP55. At the same time, through the aluminum alloy heat dissipation structure design, will occur in the process of power circuit operation heat export, natural cooling, water pump motor load large high temperature by external axial flow fan cooling. The frequency conversion controller can be installed in any form of standard water pump motor shell, also can be installed in equipment or cabinet put oneself in another's position inside the control room in the pump room. Control system modularization, miniaturization, enhance water pump control circuit IP protection grade, easy to install and use.

(the following chart is the engineering case of guangzhou respiratory center project, USES a digital integrated full variable frequency control water supply equipment)

The case to show more products

Southern medical university affiliated hospital of a project department

Jiangmen some developers building project

Zhongshan central plaza secondary water supply project installation site