A few of the improvements attained by EVER-POWER drives in energy efficiency, productivity and procedure control are truly remarkable. For example:
The savings are worth about $110,000 a year and have cut the Variable Speed Motor company’s annual carbon footprint by 500 metric tons.
EVER-POWER medium-voltage drive systems allow sugar cane plants throughout Central America to become self-sufficient producers of electricity and boost their revenues by as much as $1 million a season by selling surplus power to the local grid.
Pumps operated with variable and higher speed electrical 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 achieve these benefits, nevertheless, extra care must be taken in selecting the appropriate system of pump, engine, and electronic engine driver for optimum conversation with the process system. Successful pump selection requires knowledge of the complete anticipated selection of heads, flows, and specific gravities. Engine selection requires suitable thermal derating and, at times, a coordinating of the motor’s electrical characteristic to the VFD. Despite these extra design considerations, variable swiftness pumping is now well accepted and widespread. In a straightforward manner, a discussion is presented about how to identify the huge benefits that variable swiftness offers and how to select parts for hassle 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 are similar to check valves found in plumbing systems. They enable current to flow in mere one direction; the path shown by the arrow in the diode symbol. For instance, whenever A-stage voltage (voltage is similar to pressure in plumbing systems) is usually more positive than B or C stage voltages, then that diode will open up and invite current to flow. When B-stage becomes more positive than A-phase, then the B-phase diode will open up and the A-stage diode will close. The same holds true for the 3 diodes on the negative aspect of the bus. Thus, we obtain 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 operates in a similar fashion to a reservoir or accumulator in a plumbing program. This capacitor absorbs the ac ripple and delivers a soft dc voltage. The AC ripple on the DC bus is typically less than 3 Volts. Therefore, the voltage on the DC bus turns into “approximately” 650VDC. The real voltage will depend on the voltage level of the AC series feeding the drive, the amount of voltage unbalance on the power system, the engine 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, may also be just known as a converter. The converter that converts the dc back again to ac is also a converter, but to distinguish it from the diode converter, it is usually referred to as an “inverter”.
In fact, drives are a fundamental element 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, oil and gas, power generation, and pulp and paper.