Applying a frequency converter to a pump to reduce speed and therefore flow, causes the pump curve to shift down as shown in figure 4. Since the operating point is still the new reduced pump curve and the system curve, the same reduced flow (note 700 GPM from 1200 GPM in figures) is achieved as with a valve. This flow is achieved but at a reduced pressure. Operating at reduced pressures can result in longer pump seal life, reduced impeller wear and less system vibration and noise.
In 2003, a Mining company invited biding and two frequency inverters are selected. Since the frequency inverter installed, it has been operated normally. The economic and technical effects are obvious. The operating condition of heavy medium pumps has been improved considerably and the technical requirements are satisfied. The practice has proved that the project is successful. From the existing materials, we can see that the frequency inverter is the first option for the VF speed regulation of high-voltage, high-power asynchronous motors for heavy medium pumps in coal mining and also the first option in the same industry in the country. Thus, it has advanced level in the country.
This application analyzes technology characters of frequency inverter and its energy saving effect. Combining technics characters of condensing pump, it makes energy saving estimation. The power plant has 8 machines with capacity of 1280MW. In order to abide by state policy of energy saving and emission reduction, the plant planned to make reconstruction with frequency inverter for condensing pumps of two 300MW machines.
This application states energy saving reconstruction on ID fan and FD fan of 4# boiler in a Chinese Oil Industry Company, introduces reconstruction purpose, scheme, implementation and principle. It analyses reconstruction effect, especially the economy effect, illustrates meaning of reconstruction. Variable frequency adjustment is an effective way of source saving management.
Frequency inverter reconstruction of Power Plant promoted heightening of economy benefit. Frequency inverter won acceptance of user as its high reliability, flexible adjustment and simple operation.
Through analyzing the application, economic profit and security of two kinds of Medium voltage frequency inverter, this application compares their application effect in power plant.
When the frequency inverter is installed, it can decrease the pump speed from N1 to N2 with the pipe network resistance curve (1) being unchanged, so the working intersection A transfers to C. At this time, the consumed axis power can be represented by the area of H3COQ2. Compared with H1BOQ2, it is easy to find out that the inverter has prominent energy-saving capacity.
When adopting the frequency inverter to conduct speed adjustment, the fan speed will reduce from N1 to N2. As the fan's static pressure Pst=0, conforming to the similarity theorem, the wind pressure and wind quantity characteristics curve(P-Q) at the speed N2 can be represented by the curve (4), which converges the curve (2) at point C. At this time, the wind pressure is assumed as P3 and wind quantity is Q2, so the axis power N3=K*Q2*P3, which can be represented by the area of CP3OQ2.
Gozuk EDS1000 series frequency inverter can meet the demand of extruding machines completely, easily achieve the control target, the same time, has the "zero servo" function, which can make the machine has high torque when running at 0 Hz. The automatic energy-saving function will reduce the output current with the change on the torque. This function can not only save energy, but guarantee the reliability and steady of the system technically, which has become the first choice in the extruding machine.
Energy-saving frequency inverter drive detects the proportional pressure and proportional flow signals from the injection molding control system and adjust the motor speed needed by each step timely (flow regulation), which makes the flow and pressure of pump just fit for the system's need. While in off-working status (mainly cooled status), stopping the motor will save more energy. Concluded speaking, the regulating-frequency technology can bring great energy-saving effect to the machine.
Gozuk frequency inverter can test the pressure and flow signals from the disk type machine and track and control the output power, pressure and flow. This is equivalent to changing the fixed pump into energy-saving pump, the previous system is fit for the whole machine's demand power. Gozuk inverter can achieve energy-saving purpose and also reduce the vibration of opening and closing the mold largely, which can keep the products' quality stable, reduce the defective problem and prolong the machine's life.
Gozuk EDS2000 frequency inverter has the advantages of high torque, high-precise speed, and complete function. It can test the dynamic operating parameters automatically and adjust correspondently, to ensure the motor works in the best status. Hence, Gozuk inverter can take place of AC servo system for its high performance-price ratio. It is used widely in NC lathe.
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inverter serviceHigh quality frequency inverters for electric motor speed controls in energy-saving solutions.