E-Mobility with Demke DC/DC converter in swiss ePedelec

DC/DC buck-boost converter with 29V output voltage and switch-on threshold at 7VDC

Our Demke DC/DC Converter 257LE1-29 is in permanent operation on the road and makes the daily life of many delivery people easier. An ePedelec (cargo bike) from KYBURZ is used for the delivery of letters and parcels in urban areas. With our integrated DC/DC converter, the pedalling energy of the delivery person is fed into the batteries. Thanks to the very low switch-on threshold of 7V, even the smallest pedalling movements are converted into electrical energy. We are pleased that we can support this new way of delivery with our robust and universally applicable devices and promote the future of e-mobility.

The DC-Transformer 257LE1-29 can also be used as a DC charging converter in supercapacitor powered systems with an output-side battery. At 200W output power, this DC/DC converter boosts an input voltage of 6-28V to 29V output voltage.

Either in automated guided vehicles (AGV) or manned transport vehicles such as the ePedelec. Even before the switch-off threshold of 6V, this DC charge converter can charge a battery connected on the output side with the full charging current. This allows the electrical energy stored on the primary side of the systems to be fully utilized and the vehicles remain in operation for a longer period.

Finally, we summarize the most important parameters of the DC/DC converter with 29V output. Customer specific adjustments (DC-Master 25X) for your application are always possible. The maximum values are written in brackets.

• Ultrawide input voltage range : 6 … 28 VDC (Vin_max to 100 V)
• Switch-on threshold: 7 VDC // Switch-off threshold: 6 VDC (any increase is possible - reduction is difficult, because the high input currents cause large voltage drops)
• Very high efficiency: up to 96%
• Peak input voltage: 30 VDC (can be extended to 100 V)
• Output voltage: 29 VDC // max. output current: 6.5 ADC

The minimum input voltage defines the maximum power. In this version, we work with 7V input voltage and 29V output voltage at a dutycycle of almost 1:5 and a peak current up to 50A! Even this high current can be handled well by our semiconductors and filter elements, which are sufficiently dimensioned.