Yazar "718066" ile 'a göz atma
  • Öge
    Simulation and circuit design of an inverter driver with sensorless field oriented control for a PMSM used in compressor
    (Graduate School, 2022) Odabaşı, Tolga ; 718066 ; Electrical Engineering Programme
    The main purpose of this thesis is to design an inverter board with a sensorless field oriented control algorithm and to drive a PMSM with a compressor system using this inverter board. Simulation of the board is also evaluated. The measurements are taken and some comparisons are made. Finally, the measurements are interpreted and studies are carried out to improve some points. Simulation and verification of the inverter board are studied in detail before starting to the design. Summary of the study is given step by step as follows. The first attempts of design of a permanent magnet synchronous motor with low quality hard magnetic materials were attributed in 19th century. Magnets with high energy density began to be used in motors around the 1950s and usage of these types of motors has started to accelerate due to developments in material science. The removal of the brush system in a motor structure has reduced maintenance and caused a motor to be designed more compact with high energy density. Nowadays, permanent magnet synchronous motors have become indispensable for many usage areas such as industry, white goods, transportation, military and so on due to their high reliability and high-power density. With the appearance of switching power transistors and silicon-controlled rectifiers, the mechanical commutator driving system was replaced by an inverter-based driving system in late 1950s. Various inverter topologies have been designed such as flying capacitor multilevel inverter and diode clamped multilevel inverter. As semiconductor technology improves dramatically, wide bandgap switches such as SiC and GaN have become popular especially in driving systems because of their high efficiency. As a result of PMSM and hardware technology developments, motor control theory has also developed. Six-step control which is also called as trapezoidal control is preferred in inverter systems at the early works. In this control theory, ratio of voltage and frequency is kept as a constant at each rotor speed. In addition to that, this is also called a scalar control technique due to the absence of vector information of voltages. Hall sensors are used to determine rotor position for a commutation time. Six-step control can cause torque ripple and also the dynamic response of six-step control can be insufficient for critical loads. In order to enhance the dynamic performance of systems, field oriented control was developed. This is a vector control and the main purpose of the theory is to keep magnetic fluxes of rotor and stator perpendicular to each other at every position of the rotor. So, the torque value is maximum in this condition. In order to do that, torque and flux components of the stator currents are derived and torque component is aimed to be maximized. Some matrix transformations such as Clarke and Park are needed for these calculations. In sensorless field oriented control, the rotor position is determined by observing the BEMF signal in the stator winding rather than using hall sensors.