Blog of motion control, electrical machinery, automation, process control, motor control, green energy...

 The energy savings for operating point A1 over P1 is 17.8 KW (Refer to figure 2 below). If the cost of electricity is $0.06 per KWH, and the system operates for 1,000 hours at 4,000 GPM, the savings utilizing an VFD (AC drive, VSD drive, frequency inverter), is $1,068. If the flow is 3,000 GPM for 1,000 hours, the savings is $2,376. As you can see, the savings on energy bill can be significant over the life of the installation.

Figure 2

 The Static Head component is the elevation difference between the liquid level on the suction side of the pump and the point of liquid discharge. It is fixed in a system and does not vary with flow. The Pressure Head is established by the application or process. This factor is also independent of flow.

Figure 1

 When looking to apply VFD (VSD, AC drive) control to an existing pump, a simple overview of the application should be investigated. 

 The requirement to reduce the need for additional electrical generating stations has created a benefit to the consumer in the form of demand side management. Utility rebates in some countries provide an excellent opportunity to upgrade and maximize efficiencies at minimal, or even virtually no cost to the industrial users.

 But in recent years, the technology of AC variable frequency drives (VFDs, VSDs, frequency inverters) has evolved into highly sophisticated digital microprocessor control, along with high switching frequency IGBTs (Insulated Gate Bi Polar Transistors) power devices. This tech evolution has led to significantly advanced capabilities from the ease of programmability to expanded diagnostics. 

 ARC says that the low-power AC drives (VFDs, variable speed drives, VSDs, frequency inverters) market is highly fragmented and suggests several techniques that suppliers are using to differentiate themselves from each other and to offer better value to users and OEMs.

 The expanding economies of emerging countries are also creating a greater need for automated buildings, while the need for more electricity is driving huge investments in the power sector. All of these industries need AC drives (VFDs, VSDs, frequency inverters).

 As well as controlling speeds and cutting energy costs, AC drives (variable frequency drives, VFDs, frequency converters) also offer other attractions, such as soft-start capabilities, high power factors, and reliable operation.

 According to ARC, the global market for high-power AC drives (frequency inverters, VSDs) will grow at a CAGR (compounded annual growth rate) of 9.1% over the five years to 2011. This market will expand to almost $7.4bn by 2011. In fact it was already worth more than $4.7bn last year,.

Developments in the global market of AC drives (frequency inverters, variable speed drives, VSDs) remained positive in the second quarter of 2011. Growth of the market was strongest in the Asia and Pacific region, but the markets in Europe and North America also developed as we expected. And Germany remains the engine of growth in the market of Europe.

Demand for AC drives (frequency inverters, variable speed drives, VSDs)  was evenly divided among all the main industrial sectors. One important factor is that the demand of AC drives (frequency inverters, variable speed drives, VSDs, VFDs)  in the marine industry showed clear signs of picking up in all main market areas. There are still strong seasonal fluctuations in demand for products for the generation of renewable energy.