Concepts

Dr. Fuld Ing.-GmbH
Frankfurter Landstr. 112

D-61352 Bad Homburg

Phone:+49 6172 928928
Fax: +49 6172 928927

Distributed power supply with alternating voltage or alternating current bus; space-saving, efficient and economical alternatives to systems with DC-bus
Buck-/inverter combination; needs no chokes at the secondary side
SMPS without voltage regulation; simply, economically
Uninterruptible direct current supply (patent application DE 42 42 327 as pdf-file, 700 KB, German); efficient and economical alternative to USV systems
Power supply with long backup time; cost-efficient solution
Economical DC/DC converters with and without potential separation, also without output electrolytic capacitors
Very inexpensive switched voltage inverters without potential separation
Power-supplies with standby supply: Small no-load consumption

Inverter at the three-phase line with very high switching frequency; noiseless, small harmonic losses in the machine, efficiency approx. 97%
Economical electronic charging circuit for dc-link inverters; compact, reliable and efficient
Burn in systems with energy recovery; small energy costs
Energy recovery units for power semiconductor snubbers; reduced energy costs

Generally admitted topologies (flyback converter, forward converter, half bridge, full bridge) for input voltages up to 1500 V d.c.; fast realization, small development risk
Phase shift bridge; high efficiency and high switching frequency; compact structure
Synchronous rectification; reduced losses
Load sharing to connect several modules in parallel; redundancy; no overloading of individual modules
Battery-careful charging circuits; high battery life
Inductive control loop feedback; without optocouplers
Transformer design with consideration of eddy current losses (Skin- and proximityeffekt)

Power factor correction circuits; Fulfilment of EN61000-3-2; regulated DC-voltage above amplitude of the line voltage; energy recovery possibility realizable; also compact design with SiC diodes
Inrush current limiter, also for fulfilment VDE0160/W2-Impuls; protection from input overvoltages
Wobbled switching frequency; reduction of the EMC-noise voltages, smaller filter expenditure
Driving circuits for power semiconductors (MOSFET, IGBT, GTO, IGCT), also without transformers; integrated protective functions; for thse also favorable power supply solutions
Use of PCb-transformers (flat transformers), e.g. as current transformers
Oscillatory circuits for switching at zero current (ZCS; forced commutation); low-loss switching from power semiconductors with high frequency