Adjustable Power Supply v18.08

Arduino PWM code and voltage sensing

This code is far from finalized and represent only one of many possible design approaches. Post as many variations or improvements as you can as long as they have advantages.

Design buck/boost converter circuit/module

Volt-second balance on the inductor means that the average voltage across it over one switching cycle is zero

Discontinuous mode is when current through the output inductor is zero for part of the switching cycle

Figure out ways to salvage or build transformers

Investigate ways to use high frequency for more efficiency in power transformation as well as smaller inductors.

With new Silicon Carbide MOSFET technology, maybe feasible to use flyback transformer at high frequency as described here. A suitable MOSFET for this application costs around $15 but could be offset by smaller transformer.

Design

This page is a great guide.

Applications

Powering 3D printer

Workbench power supply

Charging batteries

Requirements

At least 360W output (12V at 30A)

Adjustable DC voltage output up to 24V

120Vac input

Research

Safety Considerations in Power Supply Design

Inductor and Flyback Transformer Design

1200 WATT FLYBACK SWITCHING POWER SUPPLY WITH SILICON CARBIDE SEMICONDUCTORS

Inductor volt-second balance, capacitor charge balance, and the small ripple approximation

Understanding Buck-Boost Power Stages

Current Sharing in Parallel Diodes

Buck Converter Design

Open-source based synthetic medium-voltage grid model for distribution power supply systems

Existing Open-Source Projects

Programmable bench power supply EEZ H24005

Bench Power Supply

Modules

edit

Arduino Power Subcircuit

Software

Git Repository

Possible Parts

Output Capacitor: Aluminum (cheaper but more lossy), organic semiconductor (good overall), tantalum (best for surface mount) [1]

Output Inductor: Bobbin or rod-core cause more noise [2]

Forward Configuration

Transformer: XFRMR TOROIDAL 500VA CHAS MOUNT, Investigating ways to salvage transformers

Rectifier: RECT BRIDGE FAST 3PHASE I4-PAC-5

IRFP250NPower transistor (MOSFET) driven by TC1411 1A High-Speed MOSFET Driver with pulse signal originating from arduino.

(Alternative mosfet requiring no mosfer driver) IRF540N "IR" MOSFET N-Channel 33A 100V

Flyback Configuration

Bridge Rectifier: 50A, 1000V BRIDGE RECTIFIER, GBJ

Switching Transistor: MOSFET NCH 650V 39A TO247N