What is ferroresonance & its effect?
Ferroresonance is a non-linear resonance phenomenon that can affect power networks. The abnormal rates of harmonics and transient or steady state overvoltages and overcurrents that it causes are often dangerous for electrical equipment. Some unexplained breakdowns can be ascribed to this rare, non-linear phenomenon.
How do you stop ferroresonance?
Common strategies for managing ferroresonance include: Preventing open phase condition, limiting overvoltages, damping resonance with secondary load, limiting cable length, switching at transformer terminals and grounding transformer primary.
What is resonance overvoltage?
Abstract: Resonance is a phenomenon that occurs in electrical power systems of all voltage levels. The nonlinear resonance such as ferroresonance is excited in circuit with linear capacitors and nonlinear inductances. …
How does a ferroresonant transformer work?
A ferroresonant power supply is a transformer-based power supply that uses nonlinear magnetic properties and a resonant circuit to provide a stable output voltage over a wide range of input voltage.
What causes ferroresonance?
Ferroresonance can occur when an unloaded 3-phase system consisting mainly of inductive and capacitive components is interrupted by single phase means. If such a network has little or no resistive load connected and one phase of the applied voltage is then interrupted, ferroresonance can occur.
What is the need of resistance switching?
Resistance Switching helps to reduce the voltage transient surge during current chopping and capacitive current breaking.
What is purpose of damping resistor?
[′dam·piŋ ri‚zis·tər] (electricity) A resistor that is placed across a parallel resonant circuit or in series with a series resonant circuit to decrease the Q factor and thereby eliminate ringing. A noninductive resistor placed across an analog meter to increase damping.
What is a damping resistor?
This damping resistor is series-connected to the discharge circuit during the opening/closing of the disconnector to suppress the electromagnetic oscillation due to repeated gap sparks, thus reducing the amplitude and frequency of VFTO [10,11].
What do you mean by Ferro resonance?
Ferroresonance or nonlinear resonance is a type of resonance in electric circuits which occurs when a circuit containing a nonlinear inductance is fed from a source that has series capacitance, and the circuit is subjected to a disturbance such as opening of a switch.
What is resonance frequency?
The resonant frequency can also be defined as the natural frequency of an object where it tends to vibrate at a higher amplitude. For example, you could feel a bridge “shake” if the collective oscillation force from vehicles caused it to vibrate at its frequency.
Why do we calculate voltage regulation?
Voltage (load) regulation is to maintain a fixed voltage under different load. Voltage regulation is limiting factor to decide the size of either conductor or type of insulation. In circuit current need to be lower than this in order to keep the voltage drop within permissible values.
What is voltage transformer Ferroresonance?
Ferroresonance can occur when the primary of a voltage transformer is connected line to ground in an ungrounded circuit. This configuration results in the magnetizing reactance of the VT being in a parallel loop with the coupling capacitance to ground of the system (see Figure 1).