DC/DC converter expands KEB's e-mobility offering
Single-source solution for driving auxiliary units
It is not uncommon for a single electric vehicle to have a range of different voltage requirements. To help its customers meet these challenges, KEB Automation has added a new DC/DC converter to its e-mobility portfolio. The DC/DC converters are tailored to the proven modular inverter system T6 APD. The voltage conversion ensures that energy is used particularly efficiently – and this has positive effects on the resource-saving drive of electrical auxiliary units in e-buses, in agricultural machinery or within “last-mile logistics”.
DC/DC converters are used when a DC voltage needs to be converted from one voltage level to another. They can increase the input voltage as a boost converter or reduce the voltage as a buck converter. In addition to saving energy and costs, the converters also stabilize the output voltage, which is particularly important for the operation of sensitive electronic devices. With this in mind, DC/DC converters can be found in laptops, solar energy systems, and wind turbines. However, electric mobility in particular represents an interesting field of application, since various voltage levels have to be provided for different components and functionalities here.
“With our T6 APD inverter system, we are a long-standing partner in the field of powering auxiliary units in electric vehicles. The addition to our portfolio means that in the future we will be offering inverters and converters from a single source. This will enable us to implement independent DC/DC solutions for cooling fans, electric steering, power supply in the driver's cab or electric power take-off (ePTO),” says Tim Hagemeier, Sales Engineer for E-Mobility at KEB. “The DC/DC converter is qualified for use in motor vehicles in accordance with E1 and has an efficiency of 94 percent,” he adds.
How does a DC/DC converter work?
The fundamental function of the DC/DC converter is based on an electronic switch that switches the DC voltage on and off at the input, thereby generating a pulsating voltage. By using a coil, the current flow can be kept almost constant when the output is under load. Capacitors are used to smooth the output voltage. In isolated DC/DC converters, voltage transformers are used to additionally establish a galvanic isolation between input and output. A control circuit monitors the output voltage and adjusts the switching operations to ensure a constant output voltage.
The new DC/DC converter features integrated protection against short circuits, no-load operation and overheating. In addition, the hardware can be connected in parallel or stacked and has CAN for controlling the output voltage. “Whether it's public transportation, municipal vehicles or agricultural machinery, the requirements for the electric drive of auxiliary units in vehicles often vary. That is why we provide the DC/DC converter with various cooling options. In addition to contact cooling, convection and liquid cooling are also possible,” says Hagemeier. The specific applications are as diverse as the environmental conditions in which the DC/DC converters have to operate. To meet this challenge, the new DC/DC converters are designed for operating temperatures from -40°C to +70°C and storage temperatures from -40°C to +85°C.
The new DC/DC converter at a glance
- E1-certified addition to the T6 APD inverter system
- 94 percent efficiency
- HV DC input voltage: 400–900 VDC
- LV DC nominal power: (1.5 kW), 3 kW
- LV DC nominal voltage: 12 VDC, 24 VDC
- Max. nominal current: (112 A), 224 A
- Operating temperature: -40 °C... +70 °C
- Storage temperature: -40 °C... +85 °C
- Various cooling options
- Can be connected in parallel/stacked
