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What is the purpose of a snubber?
A snubber is a circuit that is used in semiconductor devices for protection and performance enhancements. They have many different purposes, namely the reduction of power dissipation in power electronic switching networks.
What is diode snubber circuit?
The snubber circuit is nothing but a protection circuit, to protect the power semiconductor devices. We know that when the power diode turned off, the reverse recovery process will start. During this time, over voltage spikes will appear across the device, which should be eliminated.
What is meant by snubber?
A snubber is a device used to suppress (“snub”) a phenomenon such as voltage transients in electrical systems, pressure transients in fluid systems (caused by for example water hammer) or excess force or rapid movement in mechanical systems.
Why do you need a flyback diode?
A flyback diode or freewheeling diode is placed with reverse polarity from the power supply and in parallel to the relay’s inductance coil. The use of a diode in a relay circuit prevents huge voltage spikes from arising when the power supply is disconnected.
How is snubber RC calculated?
Calculate the minimum value for the resistor in the RC snubber by dividing the voltage across the switch by the maximum current rating. For example, suppose the voltage measurement is 160 volts and the maximum current is 5 amps. Dividing 160 volts by 5 amps gives you 32 ohms.
Why do you need a snubber circuit for a diode?
Snubber circuits are essential for diodes used in switching circuits. It can save a diode from overvoltage spikes, which may arise during the reverse recovery process. A very common snubber circuit for a power diode consists of a capacitor and a resistor connected in parallel with the diode as shown in Fig. 2.7.
How is a snubber connected to an inductive load?
Diode snubbers. The snubber diode is wired in parallel with an inductive load (such as a relay coil or electric motor ). The diode is installed so that it does not conduct under normal conditions. When the external driving current is interrupted, the inductor current flows instead through the diode.
How is a snubber used in a DC system?
This is used in systems running on DC current, and it utilizes a rectifier diode as the snubber. It basically works like this — the diode is wired in parallel with the load (like an electric motor), but it is set up so that it does not conduct under normal use.
What kind of resistor is used in a snubber?
Snubbers are also often used to prevent arcing across the contacts of relays and switches, or the electrical interference, or the welding of the contacts that can occur (see also arc suppression ). A simple RC snubber uses a small resistor (R) in series with a small capacitor (C).