Some of the improvements achieved by EVER-POWER drives in energy performance, productivity and procedure control are truly remarkable. For instance:
The Variable Speed Electric Motor savings are worth about $110,000 a year and have cut the company’s annual carbon footprint by 500 metric tons.
EVER-POWER medium-voltage drive systems allow sugar cane plant life throughout Central America to become self-sufficient producers of electrical energy and enhance their revenues by as much as $1 million a year by selling surplus power to the local grid.
Pumps operated with adjustable and higher speed electric motors provide numerous benefits such as for example greater selection of flow and mind, higher head from an individual stage, valve elimination, and energy conservation. To accomplish these benefits, nevertheless, extra care should be taken in selecting the correct system of pump, electric motor, and electronic motor driver for optimum conversation with the procedure system. Effective pump selection requires knowledge of the complete anticipated range of heads, flows, and specific gravities. Electric motor selection requires suitable thermal derating and, at times, a complementing of the motor’s electrical feature to the VFD. Despite these extra design considerations, variable velocity pumping is now well recognized and widespread. In a straightforward manner, a dialogue is presented on how to identify the benefits that variable acceleration offers and how to select parts for trouble free, reliable operation.
The first stage of a Adjustable Frequency AC Drive, or VFD, may be the Converter. The converter is made up of six diodes, which act like check valves found in plumbing systems. They allow current to flow in mere one direction; the direction demonstrated by the arrow in the diode symbol. For instance, whenever A-phase voltage (voltage is comparable to pressure in plumbing systems) is certainly more positive than B or C phase voltages, then that diode will open and invite current to flow. When B-stage 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 by adding a capacitor. A capacitor operates in a similar fashion to a reservoir or accumulator in a plumbing program. This capacitor absorbs the ac ripple and provides a even dc voltage. The AC ripple on the DC bus is normally less than 3 Volts. Hence, the voltage on the DC bus becomes “approximately” 650VDC. The actual voltage will depend on the voltage degree of the AC line feeding the drive, the amount of voltage unbalance on the power system, the motor load, the impedance of the power system, 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 to ac can be a converter, but to distinguish 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.