Pulse Width Modulation (PWM) is a very common technique to produce switching signals in DC-AC and DC-DC power electronics converters. PWM can be found in almost any area from the industry to home appliances, from single-phase to multiphase applications, such as adjustable speed drives, elevators, industrial robots, electric vehicles etc. For this reason, pulse width modulation has been intensively researched for almost 50 years in power electronics. The different PWM techniques have different performance thus the applied method depends on the type, power range and dynamic requirements of the application. The selected modulation technique also influences the efficiency and therefore the accessible profit of the system.
The main goal of this project is to examine different pulse width modulation methods and compare their performance and harmonic behavior. To achieve this purpose, a low voltage three-phase inverter has to be designed that is controlled by a DSP running the implemented modulation methods. The performance of square-wave, sinusoidal bipolar and space vector modulation techniques are compared through the results of laboratory measurements. Computer simulations are also created in the Simulink environment to observe the theoretical operation of the varying methods. The investigation of harmonic properties is achieved by fast Fourier transform.