Since the 21st century, China variable frequency drive industry is highly fission. Many foreign brands begin to set up factories in China, the implementation of the localization of business. See Appendix major foreign brands in the Chinese mainland investment. On the other hand, the original domestic brands personnel and funds continue separation, the establishment of a number of enterprises, mainly concentrated in coastal areas such as Guangdong, Zhejiang, Shandong, Shanghai and other regions.
In DC breaking, frequency inverter injects DC current in stator of Motor & with that DC current Stator will try to lock the rotor. There will be stationary field instead of rotating field in between stator & Rotor of Motor.
This is DC breaking i.e. DC injection, this application being used in cranes for increasing starting torque & in some handloom machine for breaking applications where mechanical breaks are not available or suitable.
This is DC breaking i.e. DC injection, this application being used in cranes for increasing starting torque & in some handloom machine for breaking applications where mechanical breaks are not available or suitable.
My personal preference is for an AC line reactor simply because it does a better job of protecting the variable frequency drive from the line and the line from the drive. I've always viewed a DC bus reactor on a PWM drive as a cheap attempt at filtering to save space and money over the better protection afforded by a line reactor.
There are many ways of implementing SVPWM, it is having the third harmonic sine injected in to sine phase voltages to get better DC bus utilization (15% more). About the choice of a particular modulation, the SV-PWM (implementation is not important) with symmetrical edges is the most common, and IIRC it can be demonstrated that it provides the lowest current ripple.
You might want to use an isolation transformer between the variable frequency drive and the motor if the VFD is long distance from the motor.
An output filter typically adds a resistive/capacitive circuit that mitigates the harmful "spikes", protecting both the motor and wiring especially as the distance between the motor and VFD drive increases.
An output filter typically adds a resistive/capacitive circuit that mitigates the harmful "spikes", protecting both the motor and wiring especially as the distance between the motor and VFD drive increases.
INVERTER-READY means that some of the extras required to protect the machine from the damaging effects of the drive output waveform are included.
INVERTER-DUTY (also sometimes listed as "inverter ready") means even more extras are built in. All the inverter-ready items are there.
INVERTER-DUTY (also sometimes listed as "inverter ready") means even more extras are built in. All the inverter-ready items are there.
Case: The motors from approx 22kw - 250kw and are double star-wound to facilitate a wide speed range. The motors and frequency inverters are matched. The bearings are not showing the usual ESD damage indications but we are experiencing short life (less than 8000 hours in some cases). The bearings on some units are insulated (80kw plus). Is it the bearings that re undersized or if there may be another issue?
AC reactors reduce harmonics, mitigates transient conditions and helps to maintain proper phase to phase voltages. DC reactors will also mitigate harmonics however it will provide more harmonic attenuation than a equally sized AC reactor.
AC Drives has to be selected by current and not power. That should be same but is not always. Immerged pumps for examples are using more current than standard ac motor for same mechanical power. In general current is more less linked to torque. Be aware than bellow 50% of nominal torque/current the AC drives selection can be different.
As nowadays there is a trend in green energy production and energy efficiency, what solutions/applications would you recommend in reduction consumed energy of a motor driven by variable frequency drive.
Storage battery is an important component of UPS system. Choosing battery is not only related to the cost of the manufacturers, but also affecting the reliability of continuous power supply of UPS power. Specific type and power rate can be designed according to the customers’ requirement and the battery module is based on solar power and wind power solutions.
The engineers in AC Drive China are very professional in Chinese automation industrial control fields, provide you comprehensive energy saving solutions.
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Frequency directly represents no of rotation of rotor for that machine,
the higher the frequency the more the rotation of the rotor, i.e. the
rpm of the motor there by result ...
Due to power electronics technology and microelectronics technology rapid development, variable frequency drive reforms and upgrades speed also is faster, introduce new products, ...
Since the 21st century, China variable frequency drive industry is highly fission. Many foreign brands begin to set up factories in China, the implementation of the localization ...
My personal preference is for an AC line reactor simply because it does a better job of protecting the variable frequency drive from the line and the line from the drive. I've ...
As nowadays there is a trend in green energy production and energy efficiency, what solutions/applications would you recommend in reduction consumed energy of a motor driven by ...
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Variable Frequency Drive versus Soft Starter in Harmonics
Considerations in choosing large Variable Frequency Drive
Common Mode Noise Impact in AC drive Applications
AC drives in pumps for energy saving
HMI and SCADA system
Something need to be considered in buying AC drives
ABB sine wave filter
