Introduction

Due to the experience acquired in the Alpha-DR Twins project, in 2020 I decided to improve it. Meet Alpha-DR Mark II!

Specifications

• Driver: Mini-DDR (includes phase-lead, over current detection, undervoltage-lockout, tOn limiter, DTC limiter and thermal shutdown)
• Power Supply: 220VAC full wave rectified mains, closed-loop automatic pre-charge + line filter
• Bridge: BSM150GB60DLC IGBT’s Full-Bridge
• DC BUS: Laminated, 1oz copper PCB + solder reinforcement, 1x 400V | 2.7mF BUS capacitor + 2x 400V | 1.5uF decoupling capacitors
• Resonant capacitor: 6kVDC | 73.3nF MMC, 30x WIMA MKP10 2kVDC | 22nF film capacitors, 3s10p
• Primary coil: Flat, 9 turns of 6mm^2 wire, tap at 8.5 turns, 3/8″ aluminium tubing strike ring.
• Secondary coil: ~1400 turns, 100x341mm PVC form, 333mm winding, 31AWG. Polyurethane and epoxy coated.
• Top load: 355x105mm solid toroid, 576 flat surfaces, 3D printed frame covered with aluminium tape, PU coated
• OCD: Set at 340A
• CTs: 2x 1:30:15 = 1:300 cascade, same ratio for OCD and feedback
• Resonant frequency: ~142kHz
• On-time: Up to 150us
• Duty-Cycle: Up to 10%
• Thermal protection: 50ºC
• Enclosure: 18x18x14 (cm), 3D printed frame (PETG) + acrylic
• Height: 68cm
• Streamer lenght: Up to 1.20m, measured in a straight line.
  
  To be continued…