Medium Voltage Variable Frequency AC Drive for Conveyor Application
Frequency inverter is the rise in recent years, a new technology,
which is achieved by varying the speed of power frequency
regulation, because of its speed steady, transient stability,
energy-saving features has been growing attention. With the
frequency control technology continues to mature, and Frequency
Control in the belt transport equipment are increasingly being used
on the application. GANDO produce the G11 series of belt transport
frequency control device has the following characteristics:
■ realize the soft start of the conveyor system. The use of
soft-start inverter, soft start the motor and belt drive combined
soft start, slow start by the motor, drive belt slow start, the
belt slow release of energy stored within that belt machine
capillary waves formed during start small, almost to the belt
without causing damage.
■ to achieve multi-motor drive belt when the power balance.
Application of drive to drive on the belt, generally using a drag a
control, when the multi-motor drive, the use of master-slave
control, to achieve power balance. The main shaft in a coal mine in
Shanxi belt is 3 × 135KW motor drive, the use of master-slave
control, the light load, the main difference from the motor current
is about 5A, fully loaded, a difference of about 2A. Basic
realization of the multi-motor drive belt when the power balance.
■ reduce the belt with the strong. Using inverter drive, due to the
drive starting time adjustable in 1S ~ 6500S, usually starting time
belt within the 60S ~ 200S set according to the site, the starting
time of belt extension, greatly reduce the requirements on the belt
with a strong, reduce the initial equipment investment.
■ reduce equipment maintenance. Inverter is an electronic device
integration, it will translate into the life of electronic
machinery life, life is very long, greatly reducing equipment
maintenance. At the same time, the use of the drive to achieve a
soft belt soft start function, starting the process of basically no
impact on the machinery, but also greatly reduces the mechanical
part of the belt conveyor system maintenance volume. If the main
shaft in a coal mine in Shanxi belt drive inverter is used, only
the belt buckle an annual cost savings amounted to ten thousand
■ start smooth, torque, there is no rush current, overloaded start
can be achieved.
■ energy. Machine used in the belt after the energy saving variable
frequency drive is mainly reflected in the system power factor and
efficiency of the system two ways.
a, improve system power factor
Typically, the coal mine put the motor in the design process than
large margin, most can not work full operation, the motor working
at full voltage, full speed and load are often very small, there
are part-time no-load operation. Characteristics of the motor
design and operation that the motor is only in the most efficient
close to full load, power factor best light load reduced, resulting
in unnecessary energy losses. This is because when light loads, the
active component of stator current is very small, mainly excitation
of the reactive component, so the power factor is very low. Using
inverter drive, the power factor in the whole process more than
0.9, significant savings in reactive power.
b, improve system efficiency
Using inverter drive, the motor and reducer direct hardware
connection between the middle to reduce the fluid coupling of this
link. The fluid coupling transmission efficiency itself is not
high, and is mainly to drive through the liquid, liquid hard drive
connected directly to the efficiency ratio is much lower
transmission efficiency, so using inverter drive, the system's
transfer efficiency to the total than the fluid coupling drive
higher efficiency of 5% to 10%.
In addition, the mine is usually far away from the substation, the
voltage fluctuations at different times, the use of the automatic
voltage regulator function of frequency, there are also some
In summary, the use of G11 series of belt transport frequency
control technology to transform traditional belt conveyor drive
system, not only in advanced technology or the social and economic
benefits are huge, with the frequency modulation speed technology
continues to mature, in the belt drive on the drive will dominate.
Power range of G11 VFD
Voltage: 1140VAC (959VAC – 1311VAC)
Power: 45kw/60HP – 400kw/535HP
Specification of G11 VFD
150% rated current 1min., 180% 10 sec.
sensor-less vector control, V/F control
Setting frequency menthod
Plastic Extruder Machines, multi-step speed, simple PLC and PID.
Output frequency resolution
Frequency setting signal
0~+10V; 2~+10V; 4~20mA, 0~20mA
Over voltage, under voltage, over load, relay, overheat speed
stall, grounding, instant power cut compensation( within 2 sec for
operation mode. Continue to operate after the power is available),
Charging protection( not to display when the dc voltage of main
circuit is less than 50v), up to 29 ways.
forced air cooling
Less than 0.2g for 20hz
Ambient temperature / Humidity
-10 Degrees~+40 Degrees / 20~90%Rh (no condensation)
A variable-frequency drive (VFD) is a system for controlling the
rotational speed of an alternating current (AC) electric motor by
controlling the frequency of the electrical power supplied to the
motor. A variable frequency drive is a specific type of
adjustable-speed drive. Variable-frequency drives are also known as
adjustable-frequency drives (AFD), variable-speed drives (VSD), AC
drives, microdrives or inverter drives. Since the voltage is varied
along with frequency, these are sometimes also called VVVF
(variable voltage variable frequency) drives.