660V Medium Voltage Variable Frequency Drives for Water Pumps

660V Medium Voltage Variable Frequency Drives for Water Pumps

A pump is a machine or device for raising, transferring, or compressing fluids. Pumps represent the largest single use of power in industry (31%) by motor driven equipment. Process variables, including pressure and flow of gases and liquids, have long been regulated using mechanical clutches, throttles, and adjustable inlet guide vanes. Pumps often operate as a variable torque load, a load that increases as the speed increases. These mechanisms waste energy, require frequent maintenance, and provide inaccurate control.

Pumps have two main categories:

1.?????????????? Positive displacement pumps force a fixed volume of fluid from inlet to discharge with each stroke or rotation. (e.g., reciprocating, rotary, or screw type pumps)

2.?????????????? Centrifugal pumps are the biggest class of pumps, which use the fluid's own momentum to build up pressure or head. Centrifugal pumps use centrifugal and hydrodynamic forces to create pressure that moves the fluid from inlet to discharge.

Pumps can also be classified by principle of operation and drive requirements.

· Principle of Operation Application Served

· Materials of Construction

· Liquid Being Pumped

· Shaft Orientation (Vertical, Horizontal)

· Number of Stages

· SuctionPortArrangement

Application?Challenges

· Reduce energy costs
Motors use less energy as speed is reduced.

· Reduce demand charges
Drives reduce motor starting current 8-10 times.

·Variable and constant torque load characteristics, depending on pump type.

·The motor may spin backwards due to pump backpressure when stopped.

·Control of pressure and flow is desired.

·High reliability.

·Wide horsepower range for different pump sizes.

·Environmentally friendly (harmonic standards).

·Network communications.

·Prevention of water hammer, pipe stress, valve, and pump seals and cavitation prevention.

Features of G11 matching extruder application

Power range of G11 VFD

Voltage:?660VAC?(450VAC?–?690VAC)

Power:?22kw/30HP?–?400kw/535HP

Specification of G11 VFD