Your most reliabel Medium Voltage Drive and Static Var Generator Manufacturer.
FD200 inverter frequency drive is created in line with the principle of 'Quality, Design, and Functions'. It is designed by FGI SCIENCE AND TECHNOLOGY CO., LTD. ourselves with the inspiration we find at various trade shows, and on the latest runways – all the while we constantly work to find innovative and functional solutions. This product was born out of innovation and curiosity, and it’s one of our greatest strength. In our minds, nothing is ever finished, and everything can always be improved.
The race is on. Those brands that understand what brand responsibility means and can deliver delight to their customers today will thrive in the future and command the greatest brand value tomorrow. Highly aware of that, FGI has become a star among the booming brands. Being highly responsible for our FGI branded products and the accompanying service, we have created a vast and stable cooperative clients network.
Customers can count on our expertise as well as the service we rendered through FGI as our team of experts stays with current industry trends and regulatory requirements. They are all well-trained under the principle of lean production. Thus they are qualified to provide the best services for customers.
Welcome to our latest article on the intriguing topic of Variable Drive Motors! In this read, we will delve into the world of motor efficiency and uncover how these innovative motors are transforming various industries. With their ability to enhance performance while significantly minimizing energy consumption, variable drive motors have become a game-changer for businesses across the globe. Whether you're an engineer, a technology enthusiast, or simply someone intrigued by cutting-edge advancements, this article is bound to captivate your interest. Join us as we unravel the fascinating realm of variable drive motors and explore the endless possibilities they offer.
Variable Drive Motors: Enhancing Motor Efficiency
to Variable Drive Motors
In today's rapidly evolving industrial landscape, efficiency is paramount. Companies are constantly seeking ways to optimize their operations and reduce energy consumption. One significant area of focus lies in motor efficiency. Traditional motors operate at a fixed speed, which can result in energy wastage during periods of low demand. However, variable drive motors, also known as variable frequency drives (VFDs), offer a solution to this problem. In this article, we will explore the benefits and applications of variable drive motors and how FGI is revolutionizing motor efficiency.
Understanding Variable Drive Motors
Variable drive motors are electrical motors equipped with variable frequency drives. These drives allow the motor to adjust its speed according to the specific requirements of the application. By altering the frequency and voltage supplied to the motor, variable drive motors can operate at different speeds, optimizing energy consumption. This technology offers numerous advantages, including improved control, reduced maintenance costs, and increased motor lifespan.
The Benefits of Variable Drive Motors
By adopting variable drive motors, companies can enjoy a range of benefits. Firstly, energy savings are significant. Variable drive motors adapt their speed to match the load, resulting in reduced power consumption during periods of lower demand. This leads to lower energy bills and a smaller carbon footprint. Additionally, the ability to control motor speed enhances precision and accuracy in applications, ensuring optimal performance.
Reduced wear and tear on mechanical components is another advantage of variable drive motors. The ability to ramp up the motor speed gradually helps minimize stress on various parts, leading to decreased maintenance costs and increased reliability.
Applications of Variable Drive Motors
Variable drive motors find extensive applications across various industries. In HVAC systems, these motors enable variable airflow control, resulting in improved thermal comfort and reduced energy consumption. In manufacturing processes, variable drive motors provide precise and efficient control over conveyors, pumps, and fans, leading to increased productivity and cost savings. Additionally, in transportation systems such as elevators and escalators, variable drive motors offer smoother operation and energy-efficient performance.
FGI: Pioneering Motor Efficiency
FGI, a leading provider of electrical motor solutions, is at the forefront of enhancing motor efficiency with its innovative variable drive motors. Leveraging advanced technologies, such as high-efficiency permanent magnet motors and intelligent control systems, FGI delivers optimal performance and energy savings. Not only does FGI provide robust variable drive motors, but the company also offers expert consultation and support, ensuring seamless integration into existing systems.
In conclusion, variable drive motors are transforming motor efficiency and offering substantial energy and cost savings across industries. With FGI's commitment to innovation and cutting-edge solutions, companies can achieve enhanced control, reduced energy consumption, and prolonged motor lifespans. Embracing variable drive motors is undoubtedly a wise choice for any organization seeking to optimize its operations and contribute to a greener future.
In conclusion, variable drive motors have undoubtedly revolutionized the industry, enhancing motor efficiency in unimaginable ways. With our company's 15 years of experience in the field, we have witnessed firsthand the tremendous advancements and positive impact these motors have had on various sectors. As technology continues to evolve, it is evident that variable drive motors will play an instrumental role in shaping the future of motor efficiency. From reducing energy consumption to boosting productivity, these motors have proven to be a game-changer for businesses worldwide. As we look ahead, we remain committed to staying at the forefront of this innovation, continuously striving to provide our clients with the most efficient and sustainable solutions. With variable drive motors leading the way, we are confident that the future holds endless possibilities for enhanced motor efficiency.
Welcome to our article on "Maximizing Efficiency with High Frequency Inverters", where we delve into the fascinating world of energy conservation and advanced technology. In this piece, we will explore the incredible potential of high frequency inverters in optimizing efficiency and uncover the ingenious strategies they offer. Whether you are an industry expert seeking to stay ahead of the curve or simply curious about the latest advancements in energy management, this article will provide you with valuable insights and practical tips. Join us as we dive into the intricacies of high frequency inverters and discover how they can revolutionize your approach to energy consumption.
Maximizing Efficiency with High Frequency Inverters: Revolutionizing Power Conversion Technology
to High Frequency Inverters
Innovation has a new name in the power conversion industry, and it is FGI, short for Frequency Grid Inverters. FGI is at the forefront of cutting-edge technology, offering high frequency inverters that deliver unparalleled efficiency and performance. In this article, we will explore the various aspects of FGI's high frequency inverters and how they are revolutionizing power conversion technology.
The Basics of High Frequency Inverters
High frequency inverters have become widely popular due to their ability to convert direct current (DC) electricity into alternating current (AC) with minimal power loss. FGI's high frequency inverters utilize advanced semiconductor technologies and intelligent control algorithms to achieve maximum conversion efficiency. By operating at higher frequency ranges, FGI inverters can significantly reduce the size and weight of the system, making them ideal for a wide range of applications.
Unleashing Unparalleled Efficiency
Efficiency is a key factor in any power conversion system, and FGI's high frequency inverters excel in this aspect. With a conversion efficiency of up to 99%, FGI inverters ensure that every watt of power generated is utilized optimally, minimizing energy wastage and reducing operating costs. Additionally, FGI inverters incorporate advanced cooling mechanisms and thermal management systems to enhance overall efficiency and prolong the lifespan of the equipment.
Applications in Renewable Energy Systems
Renewable energy sources such as solar and wind are gaining prominence globally, and FGI's high frequency inverters play a crucial role in harnessing their power. These inverters are specifically designed to integrate seamlessly with renewable energy systems, ensuring maximum power extraction from solar panels or wind turbines. FGI inverters guarantee stable and reliable energy conversion, enabling a sustainable and cleaner future for the planet.
The FGI Advantage: Advanced Features and Flexibility
FGI distinguishes itself in the market through its commitment to continuous innovation and customer-centric approach. In addition to their exceptional conversion efficiency, FGI high frequency inverters offer a range of advanced features to maximize user convenience and system performance. These features include intelligent grid-tie capabilities, remote monitoring and control, and compatibility with smart grid technologies. Furthermore, FGI inverters are highly flexible, accommodating various voltage and power requirements, making them adaptable to diverse applications.
FGI's high frequency inverters are truly a game-changer in the power conversion industry. With their remarkable efficiency, advanced features, and adaptability, FGI inverters provide a cost-effective and sustainable solution for both commercial and residential applications. By harnessing the power of FGI, businesses and individuals can take a giant leap towards maximizing efficiency, reducing energy consumption, and ultimately contributing to a greener future. Experience the power of FGI's high frequency inverters and revolutionize your power conversion needs today.
In conclusion, maximizing efficiency with high frequency inverters is of utmost importance for any company seeking to stay competitive in today's rapidly advancing technological landscape. With our 15 years of experience in the industry, we have witnessed firsthand the transformative power of these cutting-edge inverters in optimizing energy consumption and reducing operational costs. By harnessing the capabilities of high frequency inverters, companies can streamline their processes, enhance productivity, and ultimately secure a strong position in the market. As we continue to innovate and adapt to evolving industry demands, our commitment remains unwavering – to provide the highest quality high frequency inverters that drive efficiency, sustainability, and profitability for our valued customers.
Welcome to our informative article on AC frequency converters, where we delve into their various features and benefits. Whether you are an industry professional seeking a comprehensive understanding or simply curious about this technology, we invite you to join us in exploring the world of AC frequency converters. From their transformative capabilities to the advantages they offer across numerous applications, this article will equip you with valuable insights. So, let us unravel the intricacies of AC frequency converters and discover how these versatile devices can revolutionize multiple industries. Read on to unlock a wealth of knowledge and uncover the endless possibilities that await.
Understanding AC Frequency Converters: Features and Benefits
Introducing FGI's AC Frequency Converters
Exploring the Key Features of FGI AC Frequency Converters
The Benefits of Utilizing FGI AC Frequency Converters in Various Applications
How to Choose the Right FGI AC Frequency Converter for Your Needs
Future Possibilities and Innovations in FGI AC Frequency Converters
Introducing FGI's AC Frequency Converters
AC frequency converters play a crucial role in various industries where the efficient control and conversion of alternating current is necessary. FGI, a leading manufacturer specializing in power electronics solutions, offers a range of high-quality AC frequency converters that cater to a diverse set of applications. FGI, which stands for Frequency Generation & Incorporation, has established itself as a reliable brand in the market for delivering state-of-the-art frequency conversion solutions.
Exploring the Key Features of FGI AC Frequency Converters
FGI's AC frequency converters are designed with cutting-edge technology and incorporate several features that set them apart from competitors. One of the standout features is their robust and efficient design, ensuring reliable performance even in demanding environments. The converters also boast high power density, allowing for compact installations and space-saving solutions. With extensive operating voltage and frequency ranges, FGI AC frequency converters can handle a wide variety of power requirements.
Another notable feature is the advanced control system incorporated into FGI converters. This enables precise and accurate frequency and voltage control, ensuring optimized performance in different scenarios. Moreover, FGI converters come equipped with built-in protection mechanisms to safeguard against voltage surges, overloads, and other potential risks. These safety features not only protect the connected equipment but also contribute to enhanced system longevity.
The Benefits of Utilizing FGI AC Frequency Converters in Various Applications
FGI AC frequency converters offer several benefits to industries across various sectors. One primary advantage is their capability to convert frequency and voltage, allowing compatibility between different power grids and equipment. This flexibility enables seamless international operations for companies that need to adapt their machinery to local electrical standards.
Additionally, FGI AC frequency converters provide precise speed control for motors, enabling efficient operation in equipment such as pumps, fans, and compressors. By adjusting the speed of electric motors to match the required load, FGI converters help optimize energy consumption, leading to significant cost savings and environmental benefits.
Another advantage is the ability of FGI converters to minimize electrical harmonics, ensuring cleaner power supply. This is crucial for sensitive equipment, such as medical devices, laboratory instruments, telecommunications systems, and data centers. By reducing harmonic distortion, FGI AC frequency converters contribute to improved equipment performance, prolonged lifespan, and fewer disruptions caused by electrical noise.
How to Choose the Right FGI AC Frequency Converter for Your Needs
Selecting the most suitable FGI AC frequency converter depends on several factors specific to the application at hand. The first consideration is the power capacity required. FGI offers a range of converters with varying power ratings to accommodate different loads. Additionally, understanding the input voltage and frequency requirements of the connected devices is crucial to ensure compatibility with the converter's capabilities.
The intended field of application also plays a significant role in determining the appropriate FGI AC frequency converter. Industries such as oil and gas, mining, manufacturing, and transportation have distinct power requirements, and FGI offers converters specifically designed to meet these unique demands. By considering the environmental conditions, such as temperature, humidity, and altitude, customers can choose a converter with the necessary ruggedness and reliability.
Future Possibilities and Innovations in FGI AC Frequency Converters
As technology continues to evolve, FGI remains committed to innovation and adapting to the ever-changing needs of customers. Looking ahead, FGI is exploring advancements in digital control systems to enhance the precision, flexibility, and connectivity of their AC frequency converters. By incorporating smart features, such as remote monitoring and diagnostic capabilities, FGI aims to provide customers with real-time insights into system performance, enabling proactive maintenance and minimizing downtime.
Moreover, FGI is investing in research and development to improve energy efficiency and reduce the environmental footprint of their AC frequency converters. The focus includes exploring new materials, advanced cooling techniques, and smart power management solutions. By prioritizing sustainability, FGI aims to contribute to a greener future while delivering cutting-edge power electronics solutions to its customers.
In conclusion, FGI's AC frequency converters offer an array of features and benefits that cater to diverse applications. With their robust design, precise control, and enhanced safety measures, FGI converters provide reliable power conversion solutions. Choosing the right converter depends on power requirements, application needs, and environmental considerations. FGI's commitment to innovation ensures that their AC frequency converters will continue to evolve, paving the way for future advancements in the field of power electronics.
In conclusion, after gaining a comprehensive understanding of AC frequency converters and their numerous features and benefits, it is evident that these devices play a crucial role in various industrial applications. With our company's 15 years of experience in the industry, we have witnessed first-hand the advancements in frequency converter technology and witnessed how it has revolutionized the way businesses operate. From providing precise control over motor speed to enhancing energy efficiency and reducing operating costs, frequency converters have proven to be indispensable assets in today's fast-paced world. As a trusted industry player, our company remains committed to staying at the forefront of technological advancements and providing our clients with the most innovative and reliable frequency converter solutions available. With our expertise and experience, we are confident in our ability to help businesses optimize their operations and achieve higher productivity levels. Partner with us and embark on a journey of efficiency, reliability, and success with AC frequency converters.
Welcome to our comprehensive guide on FD200 Inverter Frequency Drives! In this article, we delve into the features and functionalities of these advanced drives, shedding light on their incredible capabilities. Whether you're a seasoned engineer or a curious enthusiast, join us as we explore the inner workings of the FD200 Inverter Frequency Drives and discover how they can revolutionize your industrial processes. Get ready to unravel the mysteries behind this remarkable technology and unlock its immense potential.
Understanding FD200 Inverter Frequency Drives: Features
Introducing FGI's FD200 Inverter Frequency Drives
FGI is proud to present its latest innovation in the field of industrial electrical equipment - the FD200 Inverter Frequency Drives. Designed to provide reliable and efficient control over motor speed and torque, the FD200 series offers superior performance and a wide range of features that are sure to meet the diverse needs of various industrial sectors.
As an industry leader, FGI has invested years of research and development into perfecting this cutting-edge technology, ensuring that the FD200 series stands out among its competitors. With its advanced features and ease of use, these frequency drives are poised to revolutionize the way businesses operate and optimize their electrical systems.
Unraveling the Features of FD200 Inverter Frequency Drives
1. Versatile Control Mechanisms: The FD200 series offers a myriad of control mechanisms, including voltage, current, and sensorless vector control. This versatility allows for precise regulation of motor speed and torque, ensuring optimal performance in any given application. Whether you require constant torque or variable torque control, the FD200 series has got you covered.
2. Enhanced Energy Efficiency: FGI understands the importance of energy efficiency in today's eco-conscious landscape. The FD200 drives are designed to optimize energy consumption, resulting in reduced operating costs and a smaller carbon footprint. With features such as sleep/wake-up mode, adjustable motor parameters, and energy-saving algorithms, these drives ensure maximum efficiency without compromising performance.
3. Advanced Fault Diagnosis: Any downtime can be costly for businesses, and that's why the FD200 series incorporates advanced fault diagnosis mechanisms. Equipped with real-time monitoring capabilities, these drives can quickly detect any abnormalities in the system and provide accurate fault diagnosis, allowing for prompt troubleshooting and minimized downtime.
Seamless Integration and Networking Capabilities
1. Easy Installation and Commissioning: FGI understands the importance of hassle-free installation and commissioning processes. The FD200 series comes with intuitive software and user-friendly interfaces, enabling seamless integration into existing systems. With clear instructions and minimal wiring requirements, businesses can save time and resources during the setup phase.
2. Networking Capabilities: In an increasingly interconnected world, the FD200 series empowers businesses with networking capabilities. These drives can be easily integrated into existing network infrastructures, enabling remote monitoring, control, and real-time data exchange. With features like Modbus, Profibus, and Ethernet connectivity, businesses can enhance overall productivity and streamline operations.
Safety Measures and Comprehensive Protection
1. Overload and Short Circuit Protection: The FD200 series prioritizes safety, incorporating robust protection mechanisms such as overload and short circuit protection. These features automatically detect and respond to abnormal operating conditions, ensuring the longevity of the equipment and enhancing personnel safety.
2. Motor Stalling and Overheating Prevention: To safeguard motor components and prevent overheating, the FD200 drives are equipped with stalling and overheating prevention features. By continuously monitoring motor performance, these drives proactively regulate the temperature and prevent potential damage, ensuring enhanced durability and optimal motor functioning.
Applications and Benefits of FD200 Inverter Frequency Drives
The versatility and advanced features of the FD200 series make it suitable for a wide range of industrial applications. Some key sectors that can benefit from these drives include:
- Manufacturing: Optimize motor control in assembly lines, conveyor systems, and packaging machinery.
- HVAC Systems: Achieve precise temperature and airflow control in heating, ventilation, and air conditioning systems.
- Pumping Systems: Regulate pump speed and optimize water management in irrigation, wastewater treatment, and other pumping applications.
- Renewable Energy: Improve the efficiency and control of renewable energy systems like wind turbines and solar panels.
- HVAC&R: Enhance the performance of refrigeration units and cooling systems in commercial and industrial settings.
In conclusion, FGI's FD200 Inverter Frequency Drives offer a wide array of features that set them apart from the competition. With advanced control mechanisms, networking capabilities, and comprehensive protection measures, these drives are poised to revolutionize the way businesses optimize their electrical systems. Whether in manufacturing, HVAC systems, pumping systems, renewable energy, or HVAC&R, the FD200 series ensures superior performance, energy efficiency, and safety. Embrace the power of FGI's FD200 Inverter Frequency Drives and unlock endless possibilities for your business.
In conclusion, after gaining a comprehensive understanding of FD200 Inverter Frequency Drives and their features, it is evident that our 15 years of experience in the industry has played a crucial role in our expertise in this particular field. As a company, we have witnessed the evolution and advancements of these drives, allowing us to offer top-notch solutions to our clients. Our in-depth understanding of the features of FD200 Inverter Frequency Drives enables us to provide our customers with tailored recommendations and unparalleled support. With our extensive knowledge and experience, we are confident in our ability to continue delivering remarkable results and staying at the forefront of this ever-evolving industry.
1.Overview
At present, the world is troubled by the energy shortage, China's energy situation is particularly severe. In the face of such a reality, the country has a series of countermeasures, so it promulgated the "Energy Conservation Law", and called on the whole society to build a resource-conserving society. Energy saving transformation is one of the effective ways, there are many aspects of energy saving transformation, among them, through the high voltage and high power motor frequency conversion speed regulation to achieve energy saving, is undoubtedly the greatest potential of energy saving. With the increasing maturity of high voltage and high power frequency conversion technology, it is possible to apply this technology in high power water pump in water plant. It is under this situation that the water supply and drainage plant of Sinopec xx Co., Ltd. studies and transforms the high voltage frequency conversion technology of the water pump equipment.
2. Implementation plans
Sinopec Co., Ltd. is known as the pearl of Sinopec and is well known in Shandong province. petrochemical water supply and drainage plant for the company's water supply system, xixia water distribution station is one of the subordinate units of water supply and drainage plant, day design water supply capacity of 200000 tons, clear water pump room is equipped with five pump unit, unit power is 550KW / 6 KW, transform all constant speed before running, the water size by changing the size of the valve opening adjustment. The purpose of controlling the water pump: to keep the hydraulic pressure of the frequency converter constant; Under the maximum opening of the pump outlet, change the output frequency through the frequency converter to adjust the water supply at the speed to change the water supply; to reduce the impact of the pump start and stop on the pipe network.
After multiple investigations and the cost performance, Petrochemical water supply and Drainage Plant decided to choose the FGI FD5000 series high voltage inverter produced by FGI Science And Technology Co., Ltd., for the speed regulation transformation of the 2 # and 4 # pump units of Xixia water distribution station. After the cooperation of the technical personnel of both sides, the frequency conversion transformation plan of the pump unit was jointly formulated. The field equipment diagram is shown in Figure 1 below. The transformation scheme adopts the form of one area 2, that is, the high voltage frequency converter drags any unit of 2 # and 4 # of the water distribution station. When one of the units is faulty or repaired, the frequency converter drags the other unit for frequency conversion operation. Units 2 # and 4 # of water distribution station are of the same type, and the main parameters of motor and pump of 2 # unit are as follows:
petrochemical water supply and drainage plant decided to choose FGI FD5000 high voltage frequency converter one drag two control system to 2 #, 4 # water pump units for speed regulation transformation.
FGI FD5000 high voltage frequency converter it is a full digital AC high voltage frequency converter control device, using advanced power unit series carrier shift phase technology, sine wave PWM modulation method, full Chinese operation interface, with high reliability, superior performance, easy operation and other characteristics, the specific design requirements are as follows:
(1) The system efficiency is high. Under the rated working condition, the total efficiency is above 96%, and the partial efficiency of the frequency converter is greater than 98%.
(2) The input side is 36 pulse rectification, and the harmonic voltage and harmonic current content of the power grid caused by the frequency converter meet the technical requirements of IEEStd519-1992 and GB / T14549-93 "Harmonics of Power Quality Public Power Grid".
(3) The rated input power factor of the frequency converter is greater than 0.96, without the power factor compensation device.
(4) The inverter output harmonic content is low and can drive ordinary high voltage motor without increasing the motor temperature rise and reducing the motor capacity, the motor cable has any length limit; protect the motor insulation from the damage of dv / dt stress; the service life of the equipment is not reduced due to the harmonic torque.
(5) It has the function of unit bypass. When a unit fails, the system can automatically bypass it and continue to operate to ensure the reliability of the system.
(6) Full Chinese operation platform, 10.4-inch real color LCD display, touch screen direct operation, more suitable for the use of Chinese habits.
(7) The modular structure of the power unit is interchangeable and easy to maintain.
(8) The input voltage range is wide and can be operated continuously within 6KV (± 20%).
(9) The power unit is controlled by optical fiber communication, completely electrical isolation, and has strong anti-interference.
(10) Built-in PID regulator, which can realize closed-loop operation.
(11) Built-in PLC enables flexible control of different application sites.
3.Application advantage
The FGI FD5000 high voltage frequency converter was successfully tested and passed the acceptance of Petrochemical water supply and drainage plant. The FD5000 high voltage frequency converter ran well. From the perspective of the application effect of the frequency converter in operation, the purpose of the pump has been fully achieved, and its advantages before the transformation are reflected in:
(1) Easy to operate and easy to observe.
All the data and operation status of the inverter can be displayed on the display screen of the upper computer, such as operating frequency, input voltage, input current, output voltage, output current, open closed loop, pressure value, etc. The upper computer display screen operation is simple and clear, easy to observe.
(2) The frequency converter operates stably and has good performance.
Since the FGI FD5000 high voltage frequency converter is put into operation, the operation is stable, the speed adjustment is smooth and reliable, the voltage and current are normal, and no abnormal phenomenon occurs.
(3) Reduce the labor intensity of the personnel on duty.
Because the frequency converter has the valve linkage function, with the change of water supply, the personnel on duty through the microcomputer remote monitoring system on duty, no longer need to frequently open and stop pumps and valves, the workload is greatly reduced.
(4) Constant pressure control.
The pressure closed-loop constant pressure control is adopted. The user only needs to set the required pressure according to the actual water supply needs. The frequency converter automatically runs with constant pressure. The pressure setting is convenient, accurate and stable, to ensure the stable operation of the pipe network and improve the quality of water supply.
(5) Reduced maintenance costs.
Because the frequency converter realizes soft start to the motor, the starting current is small, there is no mechanical impact on the pump unit, reducing the flow rate is also conducive to reducing the possibility of cavitation of the centrifugal pump, correspondingly extending the service life of the pump, motor and valve, greatly reducing the maintenance workload and maintenance cost.
(6) Analysis of power-saving effect:
The transformation is the production water of petrochemical water supply and drainage plant. In the production water, the power plant is a large household, and the water supply pressure is mainly to meet the demand of the power plant. The water plant generally opens two pumps to meet the water supply requirements. When replenishing the power plant, the water supply pressure should be increased to 0.56MPa, and the first water supply is about 20-30 minutes. There is no certain rule. When the water supply is not replenished, the pressure is maintained at 0.50MPa. After frequency conversion transformation, using constant pressure water supply, from figure 6, the variable frequency pump and the power frequency pump running in parallel characteristics curve, power frequency pump running curve is shown in the figure F1, point C is the single pump working point, F2 is the same pump power frequency running characteristic curve, A is the working point, head Ha = Hf, flow Qa = 2 Qf. When the flow rate changes from Qa to Qb, the resistance curve of the pipe network becomes R2, and the above correspondence is still true. At this time, the loss of the head line is Δ H=2 * (Hb-Ha) (when adjusting the valves of two pumps) or Δ H=He-Ha (when adjusting the valves of one pump). Using a variable frequency pump and a power frequency pump parallel running water supply, F3 for frequency pump running alone characteristic curve, F3, F1 under the parallel operation of working head equal principle, flow sum, two pump running curve F4, the flow Qb = Qd + Qf head Ha = Hd = Hf, from figure 6, when the greater the flow reduction.