Some of the improvements achieved by EVER-POWER drives in energy efficiency, productivity and procedure control are truly remarkable. For instance:
The savings are worth about $110,000 a year and also have slice the company’s annual carbon footprint by 500 metric tons.
EVER-POWER medium-voltage drive systems allow sugar cane Variable Speed Electric Motor plants throughout Central America to be self-sufficient producers of electrical energy and increase their revenues by as much as $1 million a calendar year by selling surplus power to the local grid.
Pumps operated with variable and higher speed electric motors provide numerous benefits such as greater selection of flow and mind, higher head from a single stage, valve elimination, and energy conservation. To attain these benefits, however, extra care should be taken in selecting the correct system of pump, motor, and electronic engine driver for optimum interaction with the process system. Effective pump selection requires knowledge of the full anticipated selection of heads, flows, and specific gravities. Engine selection requires suitable thermal derating and, sometimes, a complementing of the motor’s electrical characteristic to the VFD. Despite these extra design considerations, variable acceleration pumping is now well recognized and widespread. In a simple manner, a debate is presented on how to identify the huge benefits that variable rate offers and how exactly to select elements for trouble free, reliable operation.
The first stage of a Adjustable Frequency AC Drive, or VFD, is the Converter. The converter is usually comprised of six diodes, which are similar to check valves used in plumbing systems. They allow current to flow in only one direction; the path shown by the arrow in the diode symbol. For instance, whenever A-phase voltage (voltage is similar to pressure in plumbing systems) is definitely more positive than B or C phase voltages, after that that diode will open and invite current to movement. When B-phase becomes more positive than A-phase, then your B-phase diode will open and the A-phase diode will close. The same holds true for the 3 diodes on the negative aspect of the bus. Therefore, we get six current “pulses” as each diode opens and closes.
We can get rid of the AC ripple on the DC bus with the addition of a capacitor. A capacitor works in a similar style to a reservoir or accumulator in a plumbing system. This capacitor absorbs the ac ripple and delivers a smooth dc voltage. The AC ripple on the DC bus is typically less than 3 Volts. Thus, the voltage on the DC bus turns into “approximately” 650VDC. The actual voltage will depend on the voltage degree of the AC range feeding the drive, the level of voltage unbalance on the power system, the electric motor load, the impedance of the power program, and any reactors or harmonic filters on the drive.
The diode bridge converter that converts AC-to-DC, is sometimes just referred to as a converter. The converter that converts the dc back again to ac can be a converter, but to tell apart it from the diode converter, it is usually referred to as an “inverter”.
Actually, drives are an integral part of much larger EVER-POWER power and automation offerings that help customers use electricity effectively and increase productivity in energy-intensive industries like cement, metals, mining, coal and oil, power generation, and pulp and paper.