Power MOSFET is a voltage controlled device. Why?

1 Answer

Answer :

Because the output (drain) current can be controlled by gate-source voltage.

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Last Answer : Because the controlling parameter is gate-emitter voltage.

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Last Answer : It converts fixed ac voltage into variable dc voltage.

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Last Answer : The delay angle is the angle at which thyristors are triggered after zero crossing. After zero crossing of supply voltage, one pair of thyristors is forward biased. After delay angle(α) these SCRs are triggered.

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Description : Why Generation Voltage in Power Plant is Low (11kV to 33kV) ?

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Last Answer : It means that the stages of voltage controllers in parallel triggered in a proper sequence one after the other so as to obtain a variable output with low harmonic content.

Description : What type of gating signal is used in single phase ac voltage controller with RL load?

Last Answer : High frequency carrier gating signal is used for single phase ac voltage controller with RL load.

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Last Answer : The control range is Φ< α

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Last Answer : The main draw back is the introduction of harmonics in the supply current and the load voltage waveforms particularly at low output voltages.

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Last Answer : a. High efficiency b. Flexibility in control c. Less maintenance

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Last Answer : already answered here is mosfet current controlled device?

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Last Answer : Different losses that occur are Forward conduction losses during conduction of the thyristor Loss due to leakage current during forward and reverse blocking. Power loss at gate or Gate triggering loss. Switching losses at turn-on and turn-off.

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Description : What is meant by negative converter group in a cycloconverter?

Last Answer : The part of the cycloconverter circuit that permits the flow of current during negative half cycle of output current is called negative converter group.

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Last Answer : The part of the cycloconverter circuit that permits the flow of current during positive half cycle of output current is called positive converter group.

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