I have been learning power supply theory and looking various kinds of circuits which can be used in various electronics circuit designs like powering Arduino or ESP32 based wifi controlled RC car or diy drones. I think I started looking into power supply circuit after I learned how to make RC car and drones. Because I realized that batteries and power supply circuit has large impact on system performance. I knew about the rectification to dc supply circuits theories from my engineering course but not in details. During the engineering college, I only read the theory because I did not gave or had barely the time to learn practical power circuit and its components. I did not see power supply parts like the power supply transformer, inductors, type of capacitors, diodes and transistors. This is only about the basic power supply circuit from AC to DC, that is converter or regulators. I don't remember having read power supply topics like the series and shunt type voltage regulator with only transistors or voltage regulator with operational amplifiers.
So here is what I understood about the power supply subject. The power supply theory starts with introduction to AC to DC voltage regulator. Actually it starts with diode rectifiers, half bridge rectifier, full bridge rectifier, then you have also to learn about the transformers function. Overall you will learn how transformer, rectifier and filters are used to convert AC signal to DC signal, that is from 220V 50/60Hz to say +12V DC. After you have learned that basic power supply circuit, there are topics on how to build voltage regulator. Voltage regulator are used after the filter to provide constant output load or load voltage even if the output load voltage or the input voltage changes. The voltage regulator design theory starts by showing how single zener diode can be used to achieve voltage regulation. But its not efficient and so transistors are then used to improve the efficiency of voltage regulation. Then op-amp are used along with the transistors to improve the voltage regulator design. In such op-amp voltage regulator circuit the op-amp is used to provide feedback from the output and used by the op-amp to compare input and output so as to improve the voltage regulator efficiency.
After these basic voltage regulator design theory, you will next learn the linear regulator IC voltage regulators such as the popular 7805 voltage regulator IC and the LM317 voltage regulator IC. The LM7805 IC are so useful because they are designed to output +5V DC which is used in many electronics system like in Arduino,ESP32, micrcontrollers, in PC mother board etc. I used this to build a diy +5V regulated Breadboard Power supply module.
After the linear voltage regulator IC, you will next learn the Switch Mode Power Supply(SMPS) circuits and its theory. The reason for developing SMPW is based on the theory of control of energy flow to the load by using MOSFET switches and MOSFET drivers. The switches are closed and opened in sinusoidal manner achieved by applying sinusoidal pulse width modulated signals or SPWM signal to mosfet drivers and then to the MOSFET switches which can be arranged in half bridge and full bridge topology.
After you have learned the basics of SMPS theory and simple circuits. The next thing in this SMPS are the buck converter, boost converter, inverter circuits(DC to AC). There are many ways to build buck and boost converters and inverters.
Now these are power supply basic theory and I outlined where it usually starts and where it ends. But there are also other aspects such as automatic battery cutoff circuit, battery charger and battery charger modules, etc.