In portable consumer electronic devices mainly batteries are used as power sources, thus they are important components in these devices. While designing the portable devices the behavior of the charging or discharging battery must be kept in mind. Therefore during the qualification test of these instruments, the operation of their electronic circuits must be tested using batteries with different states of charge. The time and expenses needed for these tests can be shortened by replacing the batteries with special power supplies, which can accurately emulate the battery under different working conditions.
The purpose of this thesis is to design and build a prototype of a multifunctional power supply, which can emulate a Li-ion battery cell on different tempreture levels and states of charge.
The thesis lists and compares the different equivalent circuit models that can be used to emulate batteries. The main application areas and parametres of battery emulator power sources are presented. Certain key parameters are measured of an emulator power supply.
The requriements towards the designed power supply are listed, and the results of the measurements which were needed in order to use an equivalent circuit model are shown.
The thesis presents the design steps which were needed to fabricate the electronic circuits and embedded program of the power supply. The function of these components are described, and then verified with measurements. Finally the behavior of the emulator power supply and a battery are compared with measurements.