Regenerative power with variable frequency drive
An induction motor, although not specifically designed to generate power, will generate power back into the lines as long as the magnetic field in the rotor is sustained. When calculating electrical faults on load centers, one needs to consider this effect for the initial stage of the fault until the magnetic fields collapse on the motors attached to it.
The variable frequency drive is good at maintaining the rotor magnetism while reducing the frequency, since the VFD is designed for that. But most VFDs are not going to pass that energy back to the AC supply unless it has special circuitry to do so. If one busses many VFD drives together using the DC bus connection, the energy will flow back naturally and feed other loads. Otherwise the DC bus will overvoltage and often trip the variable frequency drive. A braking resistor is sometimes used to burn off the excess energy too.
The variable frequency drive is good at maintaining the rotor magnetism while reducing the frequency, since the VFD is designed for that. But most VFDs are not going to pass that energy back to the AC supply unless it has special circuitry to do so. If one busses many VFD drives together using the DC bus connection, the energy will flow back naturally and feed other loads. Otherwise the DC bus will overvoltage and often trip the variable frequency drive. A braking resistor is sometimes used to burn off the excess energy too.
Post a Comment:
You may also like:
Featured Articles
Variable frequency drive Rectifier
To understand variable frequency drive (VFD) better, it's necessary to explain some of the main parts of the variable frequency ...
To understand variable frequency drive (VFD) better, it's necessary to explain some of the main parts of the variable frequency ...What is VFD, How it works? - VFD ...
VFD is shorted for Variable Frequency Drive (also known as AC Drives and Inverters) -- that's used to make an AC motor working in ...
VFD is shorted for Variable Frequency Drive (also known as AC Drives and Inverters) -- that's used to make an AC motor working in ...VFD: Insulated Gate Bipolar Transistor ...
IGBT (insulated gate bipolar transistor) provides a high switching speed necessary for PWM VFD operation. IGBTs are capable of ...
IGBT (insulated gate bipolar transistor) provides a high switching speed necessary for PWM VFD operation. IGBTs are capable of ...VFD controlled Induction motor ...
This paper presents a procedure to measure the efficiency on an induction motor fed by a VFD by the all operation range to speed ...
This paper presents a procedure to measure the efficiency on an induction motor fed by a VFD by the all operation range to speed ...Three phase inverters
In the variable frequency drive rectifier paper, it explains how to go from three phase alternating current voltage to a direct ...
In the variable frequency drive rectifier paper, it explains how to go from three phase alternating current voltage to a direct ...
VFD manufacturers
buy@vfds.org tech@vfds.org