Design and implementation of an ultracapacitor test

Eroğlu, Hasan Hüseyin
In this thesis, a test system is designed and implemented in order to evaluate the basic electrical performance and determine the parameters of ultracapacitors (UC). The implemented UC test system is based on power electronics converters and it is capable of charging and discharging the UC under test with predetermined current profiles. The charging operation is provided by a configuration involving the AC utility grid, a step-down transformer, a diode bridge, and a DC bus filter capacitor followed by a step-down DC-DC converter. The energy stored in the UC under test, as a result of the charging operation, is discharged to a resistor bank through a step-up DC-DC converter and a DC chopper structure. The charging and discharging current applied to the UC under test is provided by means of current mode control of power electronics converters. The control mechanism of the power electronics converters and the transition operations between the charging and discharging phases of the test system is realized via a microcontroller supported hardware structure. In the scope of the thesis study, a UC module composed of five serially connected UC cells is constructed. Constant current and constant power tests are applied to the constructed UC module. The performance of the implemented UC test system is investigated by means of computer simulations and experimental results. Further, basic electrical behaviour of the constructed UC module is evaluated and the parameters are extracted experimentally.
Citation Formats
H. H. Eroğlu, “Design and implementation of an ultracapacitor test,” M.S. - Master of Science, Middle East Technical University, 2010.