3-Phase Converters |
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3-Phase
Converters
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Variable Frequency Converters (Drives) A
variable frequency drive is a system for controlling the rotational
speed of an alternating current (AC) in an electric motor by controlling
the frequency of the electrical power supplied to the motor. They are
used for motor type applications and cannot be used for non-motor,
three-phase power loads. Variable frequency drives allow manufacturers
or operators of motors to fine-tune their adjustable-speed drives.
There are two reasons why variable frequency drives are used. One, they
can save significantly on
energy costs by using a variable frequency phase converter and two, they lessen mechanical
and electrical stress on motors by regulating current.Equipment with a single-speed drive will start motors abruptly  subjecting
them to high torque and current surges up to ten times the full-load
current. The variable frequency drive soft starts the motor by
gradually increasing to the operating speed that is required. The
starting sequence of a variable frequency drive (VFD) is
monitored carefully to avoid equipment damage. When the VFD is started,
the pulse sequence to the out put switches are adjusted so the voltage
applied across the motor has a low value and frequency. As the motor
starts to spin, the voltage is allowed to increase until the motor
reaches its full capacity. If the motor were started at full frequency,
it would overload the output switches.Variable frequency drives are used in a variety of applications for various reasons. The most common usage is in pump and fan applications because they provide the most savings in energy. With a variable frequency drive, you can change motor speed by controlling the frequency of the power input. By |
being able
to adjust a pump or fan speed to get the desired rate, you can
significantly reduce energy costs. Some of the most common applications
are wastewater treatment facilities, power plants, and hot water
circulation in commercial buildings just to name a few. Variable frequency drives often produce harmonic distortion, which adversely affects power quality in electrical machinery. Installing an isolation transformer can help eliminate this problem. Variable frequency drives were not originally designed to function as 3-phase converters, in fact, most VFDs are powered from a three-phase source of electricity. When used as 3-phase converters, single-phase input powers four of the six diodes on the rectifier, and as a result, the drive must be de-rated. Usually the size of the variable frequency phase converter has to be double that of the job application.  Because
of their sensitive electronic makeup, variable frequency drives
dont have the life span of a true, 3-phase converter. Remember,
3-phase converters use a single-phase power source to produce
three-phase power loads. A variable frequency drives main purpose is
to control the rotational speed of an alternating current in an
electrical motor.It is extremely important to contact a manufacturer who has many years of experience and has a professional engineering staff that can help you in your  selection
of 3-phase converters. Since variable frequency drives have limited
capabilities when three-phase power is a major priority, it is best to
talk to an experienced engineer who can help decide what equipment would
best operate your job requirements.Thank you for selecting the 3-Phase Converter Website, and, hopefully, you will become much more educated on 3-phase converters and variable frequency drives. Also, read additional articles on 3-phase converters, which are listed below. To contact a highly trained Phase Converter and Power Specialists directly, click on Ace Phase Converters Specialists.
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3-Phase Converters
are a more economical solution to three-phase power applications.
It can cost up to $50,000 to have 3-phase power installed by local
utility companies. 3-phase converters produce a true, balanced
three-phase power source, which enables equipment to run to its optimal
capabilities. |
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