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A 24Vdc motor draws a minimum of 500mA during normal operation to 2.5A at full load. Design a power supply using a half-wave rectifier with a transformer turns ratio of 9:1.

please, kindly help me. thanks and Godbless. :)

Well I'd wire upd the transformer to a hefty diode with a big capacitor for a filter, then simulate the load with a 1 ohm resistor and see how that works.

The specs are a bit loose... How much sag and ripple can the motor tolerate? That would determine how much filtering capacitance you need. Also a real transformer, one at a reasonable price, is going to have internal resistance and leakage inductance which will cause extra voltage sag.

Why would you want to use a half wave rectifier? The DC component of the resulting current in the transformer is apt to cause you lots of problems.

It will saturate the core.

Consider a bridge or a full-wave center-tap design?

Oops.. or were you thinking of a flyback converter?

Why would you want to use a half wave rectifier?

Maybe because this is a home work assignment and others are supposed to do it for him? At least that's what the phrasing of the question suggests.

A lot of the questions posted and circuits publicised are clearly about people's homework or lab practical assignments and the like.

In answering any questions like that there's a distinction to make between offering advice, hints and suggestions and just doing it for the questioner. Helping people to learn something in the process of the discussion is one thing, doing their work for them is another.

Some thought also has to be given to the scope of a reply because with the benefit of perhaps a wider experience it can often be along the lines of "well I wouldn't start from here if I were you" whereas the question may be set in stone: a design, circuit or solution to the question as stated may be what is required as opposed to a detailed discussion of the pro's and con's of a number of possible alternatives.

:)