A thyristor in a 3-phase fully-controlled converter that supplies 660 A to a D.C. load is mounted on a 0.6 kg aluminium heat sink. If the forward voltage across the device is 1.5 V, and aluminium has a specific heat capacity of 895 J(kg °C)-¹. (ii) Calculate the steady state temperature of the thyristor junction, given that the thermal resistance of the heat sink is 0.15°C W-¹ and that of the device is 0.12°C W-¹. How long does the heat sink take to reach a steady state temperature? The ambient temperature is 40°C maximum and the thyristor is mounted directly on the heat sink.

A thyristor in a 3-phase fully-controlled converter that supplies 660 A to a D.C. load is mounted on a 0.6 kg aluminium heat sink. If the forward voltage across the device is 1.5 V, and aluminium has a specific heat capacity of 895 J(kg °C)-¹. (ii) Calculate the steady state temperature of the thyristor junction, given that the thermal resistance of the heat sink is 0.15°C W-¹ and that of the device is 0.12°C W-¹. How long does the heat sink take to reach a steady state temperature? The ambient temperature is 40°C maximum and the thyristor is mounted directly on the heat sink.

EBK ELECTRICAL WIRING RESIDENTIAL

19th Edition

ISBN:9781337516549

Author:Simmons

Publisher:Simmons

Chapter19: Special-purpose Outlets-water Pump, Water Heater

Section19.2: Water Heater Branch Circuit

Problem 8R: For residential water heaters, the Consumer Product Safety Commission suggests a maximum temperature...

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