S1E4 Chatshaala with electronics gadgets | Exploring mobile charger - Simple Power Supply and SMPS

Today we explored the SMPS and simple power supply

  • What’s inside the transformer?
  • Why convert the DC signal into high frequency after rectification? And how?
  • Controlling the output voltage by varying the frequency
  • Common failures that occur in the power supply and the ease of fixing
  • Comparing the physical layout with the schematic
  • The linear regulator and switch-mode regulator

Screenshot 2020-06-10 at 12.30.14 AM


Hello,what is heat decipent in the transformer?
Looking foward for your reply :blush:


Heat dissipation in the transformer depends on

  • Magnetization current or hysterisis loss

  • Copper loss in primary and secondary winding

Magnetization current is the no load current and represents the power required to remove the residual magnetic field of the lamination leftover from every cycle of the AC wave form. This loss is independent of load. You can measure the primary current with nothing connected to the load.
Copper loss is the loss due to the resistance of the wire in the primary and the secondary. You can measure this resistance with a multimeter and obtain the loss with P_c=I_p^2R_p+I_s^2R_s
Total power loss P_{tot}=P_m+P_c
Estimating the temprature rise from the above is an extremely hard task. It depends on the thermal resistance of the transformer’s components i.e core thermal resistance, winding thermal resistance, insulation thermal resistance, and the convection air flow in the vicinity of the transformer.
In the case of small transformers that we use for powering gadgets It is far easier to connect the load and measure the temperature with a thermometer or temprature probe in situ.