A New Voltage Control Method for Single-Phase PWM Inverters

A new voltage control method for single-phase full-bridge PWM inverters that having an output LC filter is proposed in this paper. The proposed voltage controller has a capability to realize a zero steadystate output voltage error with fast response. The zero steady-state output voltage error is achieved by using a controller that is derived by using the virtual LC resonant circuit. Fast response is obtained by using a virtual resistance that is connected in parallel with the filter capacitor. The validity of the proposed method is verified by experimental results

Current Ripple Analysis of New Double-Stator AC Drive Systems

This paper presents a current ripple analysis of new double-stator AC drive system. At first, a new double-stator AC drive system is proposed. The aim is to combine the benefits both the multilevel and multiphase system to provide the better performance to drive AC motor. The input and output current ripples of the proposed AC drive system are then analyzed. The current ripples of the proposed AC drive system are then compared to the ones of conventional double-stator AC drive system. Under the same DC input voltage, it is shown that the proposed results in less output current ripple. Under the same output voltage, the proposed AC drive system results in smaller input current and, therefore, fewer losses on the DC power supply. Experimental results are included to show the validity of the proposed concept

Analysis of Input and Output Ripples of PWM AC Choppers

This paper presents an analysis of input and output ripples of PWM AC choppers. Expressions of input and output current and voltage ripples of single-phase PWM AC choppers are first derived. The derived expressions are then extended to three-phase PWM AC choppers. As input current and output voltage ripples specification alone cannot be used to determine the unique values of inductance and capacitance of the LC filters, an additional criterion based on the minimum reactive power is proposed. Experimental results are included in this paper to show the validity of the proposed analysis method

A Control Method for Modified Bidirectional Cuk DC-DC Converter

A control method for a modified bidirectional Cuk DC-DC converter is proposed in this paper. The proposed controller is a double control loop consisting of an inner current control loop and a voltage control loop is used to control the converter. The small-signals model that is useful in designing controllers is derived in this paper. A simple PI controller is used for both controllers. The simulation and experimental results are included in this paper to validate the performance of the proposed controller

Analisis Penggunaan Autotrafo Penggeser Fasa sebagai minimisator Harmonisa Arus di Sistem Distribusi Tenaga Listrik

Sari. Meningkatnya aplikasi beban nonlinier di sistem distribusi tenaga listrik telah menyebabkan arus sistem menjadi sangat terdistorsi dengan kandungan harmonisa arus yang sangat tinggi (THD). Persentase THD arus sistem yang tinggi dapat menyebabkan beberapa persoalan harmonisa yang serius. Tulisan ini mengusulkan metode baru untuk meminimisasi harmonisa arus di sistem distribusi tenaga listrik, yaitu dengan menggunakan autrafo penggeser fasa sebagai minimisator.Dalam kasus ini, autotrafo bertindak sebagai penggeser sudut fasa tegangan suplai beban. Akibat penggeseran sudut fasa ini, beberapa komponen arus harmonisa yang signifikan pada sisi sumber tegangan sistem dapat dieleminir, sehingga harmonisa arus yang terdapat di sistem menjadi sangat minim. Secara detail, mekanisme minimisasi harmonisa arus sistem dengan menffunakan autotrafo dijelaskan, dan diberikan beberapa konfigurasi autotrafo penggeser fasa yang dapat digunakan sebagai minimisator harmonisa arus sistem. Hasil eksperimen laboratorium diberikan untuk menunjukkan validitas metode yang diusulkan. Analysis of Phase Shifting Autotransformer as Current Harmonic Minimisator on Power Distribution SystemAbstract. The increasing use of nonlinear loads has made the currents in power distribution system highly distorted with high level harmonic currents content (TIID) and created serious harmonics problems. This paper proposed a new method to minimize current harmonics in power distribution system by using phase shifting autotransformer. The loads of system are devided into two parts which are supplied by autotransformer with 30° phase shifting. The effects of the phase shifting which causes harmonic currents are cencelled, and the resulting currents harmonic in power distribution system are minimized. Detailed mechanism of current harmonic minimization is presented. Several configurations of phase shifting autotransformer are discussed and compared. The influence of load operating conditions are discussed. Experimental results are shown to verify this proposed method