Function generator has been widely used in each electronics fields recent years. In this thesis, the authors will introduce some basic structure and working principles of a function generator, moreover a function generator which can create three kinds of wave: sine wave, square wave and triangle wave has been implemented. There are many ways to build the function generator; a method of combine the operational amplifier and discrete components is introduced in this thesis. First use the RC Wien bridge oscillator to achieve sinusoidal wave; and convert it into square wave by using the shaping circuit. Lastly, use the integrating circuit to obtain triangle wave. The basic simulation software Multisim has been used to simulate the circuit.

This thesis investigates the high frequency discharging characteristics of the lithium iron phosphate battery. The investigation focuses on effects of the high-frequency current on the dischargeable capacity of the battery. Included are the current profiles of triangle, saw-tooth, and trapezoidal waves, which are produced from commonly used DC-DC converters. Experimental results show that the current with the higher frequency has less dischargeable capacity. On the other hand, the converter current resonating into and out from the battery results the additional losses. The possible reasons that affect the discharged capacities are explained by the equivalent circuit of the battery.

This works focusesof the propose and realization device for drive four quadrant bridge convertor with transistors IGBT. Final propose include drive unipolar and bipolar, choice between direct or alternative modulation.