The concept

Special solutions are expensive. We developed the HEVW platform to prove this prejudice wrong. By separating the power supply unit in an input and output module, we can customise our devices according to function and mechanics easily. With the help of internal interfaces for sub cards, we can individually upgrade the functions of the power supply units up to semi-professional laboratory power supply units with internal I²C bus and external RS232 interfaces. We can achieve these special solutions by modifying and adapting our devices. Apart from a quick modification, the user can rely on our established designs, the advantages of maintenance for standard devices, universal accessories, the advantages of approval by external auditors and cost advantages through multiple applications of modules. Another plus is the weight factor. Weighing only 10 kg, a fully assembled 3 HE rack with redundantly installed 5 kW can be handled easily.

Applications

The platform's power supplies are suitable for different applications that a power supply unit "alone" could not live up to.

• DC-UPS devices
• Portable battery chargers
• Traction chargers with IUIa characteristic curve
• Xenon (XBO) and HBO lamp ballasts
• Semi-professional laboratory power supply units
• Programmable semiconductor laser power sources
• High-performance multiple power adapters
• Redundant power supply solutions

Module description AC and DC inputs

The power entry module PFC converts a sinusodial single-phase input current into a stabilised power factor corrected, not potentially isolated intermediate circuit voltage of 400 V_DC. The PFC module is designed for operation at 230 V_ACfor power up to 1800 W. At a consistent voltage range of 85 to 264 V_AC , the converter's power output is reduced to 50% in the lower input current range (85 V_AC to 160 V_AC). Input filters for curve B input, auxiliary power supply, inrush current limitation, rectification and sieving are assembled next to the power factor correction switch. The power entry can be connected via H15 power strips, earthed sockets or MSTB (Phoenix) plug connections. The PFC module can be operated independently as a ballast unit. The converter can also be used in DC mode at 110-390 V.

Module description DC output

The EDC output module is supplied by the PFC module and delivers 700 to 1,500 W output power. The secondary control of the resonance pulse width modulator makes a wide range of applications accessible to the converter. The converter can be controlled analogue or digitally by external reference variables. A base load is added in free-wheeling operation. It helps to quickly discharge the output capacitors and improves the dynamic regulation. The resonance conversion causes minimal switching losses in the power components. The converter is controlled at the same polarisation in current mode and either at a constant voltage or at constant power. This technology with additional secondary power sensing makes it possible to also use the module as a power source. The EDC module reaches efficiencies of up to 95%. The total top efficiency of both modules can be up to 92% in the 48 V version.

Special designs

The 19-inch designs are cooled by a temperature-controlled ventilator. For water cooling according to protection class IP54, the modules can be cooled via a flanged base plate. Maximum power is limited to 35 A by the circuit board and output connector. The maximum output power is 160 V_DC. All power and voltage combinations in the listed range can be applied through adjusting the EDC output module. Creepage distances and clearances on the circuit board are designed for EN 60950, EN 60601 and EN 61010.

Using different SMT sub-assemblies, the EDC module can be adjusted to various requirements:

• Analogue interface: Voltage control 0-5 V
• Analogue interface: Voltage control 0 - 5 V
• Analogue power monitor signal
• Control via I²C bus or RS232 interface
• Characteristic control with µ-controller (programme on request)
• Characteristic control IUIa according to DIN 41773 for lead gel traction batteries
• Characteristic control IUIa according to Champion GNB technology
• Temperature tracking for charging batteries
• Decoupling diode output with DC Good Relay
• Load distribution power share for parallel operation without decoupling diode
• Interface for external ignition unit for xenon short-arc lamps
• Interface for external battery management M7 according to VDS 3 HE/ 8 TE