What is purpose of connecting thyristor bridges in parallel?

What is purpose of connecting thyristor bridges in parallel?
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1 Answer

Answer :

Thyristor bridges are connected in parallel to improve current rating.  
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Related questions

Why reactors are provided in Thyristor bridges?

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Last Answer : Reactors are provided to limit the rate of rise of current (di/dt) in the device, thereby avoiding possible damage to the device. They also effect a proper sharing of load among thyristor bridges when connected in parallel. 

What is the purpose of RC network across thyristor?

Description : What is the purpose of RC network across thyristor?

Last Answer : RC network across each thyristor protects against Hole Storage Effect.  

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Description : What is Thyristor?

Last Answer : Thyristor is a four or more layer semiconductor device & having 3 or more junctions. It is also called Silicon Controlled Rectifiers (SCR). A healthy SCR must block in both the directions at least 1MΩ resistance, a fused SCR will conducts in both directions. 

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Last Answer : It avoids oscillation of the AC machine (Rotor oscillations).  

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Last Answer : It limits the stator current.

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Description : What is purpose of Rotor current limiter?

Last Answer : It limits overloading of rotor.  

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Last Answer : It limits generator voltage & rotor voltage.  

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Last Answer : Answer: C

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Description : When the Zero sequence reactance arises? 

Last Answer : If a machine is operating with an earthed neutral, a system earth fault will give rise to zero sequence current in the machine. 

When the negative sequence reactance arises?

Description : When the negative sequence reactance arises?

Last Answer : Negative sequence arises whenever there is any unbalance present in the system. Their effect is to set up a field rotating in opposite direction to the main field.

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Last Answer : Fast response time, high reliability, interchangeability of parts during operation, less wear & tear due to static devices & less maintenance.  

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Description : What is Inverter operation? 

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What is firing angle?

Description : What is firing angle? 

Last Answer : The angle in the AC cycle at which the thyristor starts conducting at the application of positive voltage to gate is known as the firing angle (α)

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Description : How over voltage is produced in Field breaker?

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Last Answer : Silicon & Germanium are the raw materials used for making semiconductor. Semiconductors are located between conductors & insulators in the resistivity spectrum & allow current to flow only under certain conditions. 

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parallel operation of mosfet can be done more easily as compared to thyristor. why?

Description : parallel operation of MOSFET can be done more easily as compared to thyristor. why?

Last Answer : Parallel operation of MOSFET can be done more easily as compared to thyristor because the resistance of MOSFET is increases with increase in temperature. MOSFET have the positive temperature coefficient. In ... the parallel operation of MOSFET can be done more easily as compared to the thyristor.

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What does the arrangement at coordinates '62E' shown in the illustration represent? EL-0099 A. Position recording drum and stylus B. Temperature compensating thyristor C. Miniature bridge rectifier D. Twisted wire pair within a shield

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Figure 'B' shown in the illustration represents a/an ____________. EL-0067 A. silicon controlled rectifier B. junction field effect transistor C. diac thyristor D. IG MOS field effect transistor

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Why thyristor is considered as Charge controlled device?

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Do you know the advantages of speed control using thyristor?

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How output frequency is varied in case of a thyristor?

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Why circuit turn off time should be greater than the thyristor turn-off time?

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Last Answer : Circuit turn off time should be greater than the thyristor turn-off time for reliable turn-off, otherwise the device may turn-on at an undesired instant, a process called commutation failure.

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Last Answer : a. Forward conduction losses b. Loss due to leakage current during forward and reverse blocking. c. Switching losses at turn-on and turn-off. d. Gate triggering loss.

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Last Answer : A thyristor can be turned off by making the current flowing through it to zero.

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