My first high power project->need help finding informations & components

[Barny]

Hi

My name is Bernhard.
I'm an machine fitter which works a little bit with electronics.
Normally my hobby projects are in the <= 5V / <= 1A range.

This will be my first high power project.
I want to build a PWM - power source for DC-Motors and other things (inductive & resistive loads).
Max: 42VDC 30A
The whole thing should be short circuit & overload save.

Everywhere, where I search for help I get the answer: forget it or buy thing XY.
I knew its the best way to buy a high power, switched lab suply but hey, I want to learn something new.

Do someone of you knew some good design-guids to avoid some traps for an old young player?

What is the best way to select the main-components?
I knew that I will release whole smoke-clouds of magic smoke from switching transistors during the building process.
But to reduce the buckets of burned transistors I need your help.

For example:
What is the best coice of transistor in this project?
Mos-Fet, IGBT, bipolar Transistor,...?

Should I use an single big transistor or a FET-Array to share the load?
(I knew, bipolar transistros shouldn't be used parallel.)

How should I design the load-/short circuit monitoring?
Is a current-shunt with an OPV - treshhould circuit which switches of the switching transistor + a fuse enough? 

Should I build in an seperate transistor with an "braking resistor" to limit the voltage of switched of inductive loads?


I knew I'm an "Schwachstromfutzi" so please don't hit me to hard for my stupide questions.

By the way:
Don't be worried. My house wont burn down from my stupideness.
I have an propper grounded, steel-plated welding chamber with smoce suction & the Kids don't have access.