Abstract
KEYWORDS – DC/DC Convertor, Boost Convertor, Buck-Boost Convertor, Topology Switching, Vehicle Electronic
ABSTRACT
Recently, the use of DC/DC Convertor is increased by growing a number of electronic devices in the vehicle. Accordingly, needs of high efficiency DC/DC Convertors are growing. In general, the DC/DC Convertor carries out its function that electrical power source from vehicle battery or generator converts to special voltage level. And it supplies the electrical device with the constant current or voltage. This DC/DC Convertor can divide three types which are Buck, Boost and Buck-Boost Convertor. Among these, Buck-Boost Convertor covers all cases such as Input voltage is larger than output voltage and the reverse as well. This advantage is useful for vehicle. But Buck-Boost Convertor‟s efficiency is low, comparing with Buck or Boost Convertor. This causes a heat and power loss.
The earlier studies used fixed topology method. But we make the adaptive topology switching method. When the input voltage is lower than output voltage, the convertor works as the Boost Convertor. On the other hand, the input voltage is same or higher than output voltage, it works as Buck-Boost Convertor by using the Input Voltage Monitoring. It just needs two additional components comparing with Conventional Buck-Boost convertor.
To prove the effectiveness, we make a LDM (LED Driver Module) of which output voltage is 15.5V and the input voltage range is 8V~20V. We compared two LDMs. One is conventional Buck-Boost LDM. The other is topology switching LDM. To measure LDM‟s performance, Key factors are the efficiency and the heat. If efficiency is low, then, it causes voltage drop and power loss. Also, if board temperature is too high, then, it needs heat-sink. This causes cost rising. In this paper, we test all factors and comparison. It works properly on all input voltage ranges. And the result shows that topology switching method is more efficient. This study proposes new DC/DC convertor mechanism. We adopt this mechanism to LDM and prove its usefulness. This is way increasing performance and offering lower cost.