This paper proposes a configuration based on an a PR controller to enhance the power quality of a Single-Phase Five-Level Inverter (SPFLI). A sliding mode control is used to compensate the voltage ...harmonics and regulate the load supply. The proposed configuration implementing a sliding mode controller, a resonance regulator helps improving the dynamic response of the system and may target any specified voltage harmonics. A battery is interfaced with a combination Buck and Boost converters helps to reduce the nominal battery voltage, balance power, and to regulate the DC bus bar voltage. The proposed configuration is modeled, simulated and implemented experimentally in real-time on an Opal-RT simulator. The performances of the proposed system are analyzed and discussed in the paper.
In this paper, an improved hybrid maximum power point tracking (MPPT) method is presented. The proposed hybrid method is a hybrid version of fractional short circuit current (FSCC) and perturb and ...observe (P&O) MPPT method. The proposed improvement in this paper enables the hybrid MPPT method to detect the dynamic weather conditions more precisely than the previously developed methods. Moreover, under slowly varying weather condition the algorithm tracks the maximum power point (MPP) using the P&O MPPT. Thus, the proposed method experiences fewer offline (short circuit current) measurements and hence, better energy harnessing. The proposed MPPT method is validated using a buck-boost converter designed at a rated power of 125W and simulated using Simulink.
Modular Multilevel Converters (MMC) processing phase quantities at low frequency are vulnerable to high cell voltage ripples. MMC upper and lower arms processes pulsating power at fundamental and ...second harmonic phase components. As a consequence, arms are expected to buffer the energy difference exchanged between DC-link and each AC-phase. This buffered energy is translated into increased cell voltage ripple when operating at low phase frequency. Several remedies have been presented in literature, which can be classified under software and hardware methods. To address this short-come we introduced a plug-in hardware alternative that permit energy exchange between cells from upper and lower arms thus remarkably reducing capacitor voltage ripples caused by out of phase energy variations. The proposed method can improve MMC performance over the full operation region and is mainly attractive to low frequency operation such as in variable-speed motor drives where higher-than-nominal torques might be required for a wide speed range. Performed simulations over a synchronous machine using maximum torque per current control technique, conforms well with the analytical findings and shows the effectiveness of the proposed method.
In this paper, a new cell based Modular Multilevel Converter (MMC) for AC-AC and AC-DC applications is presented. The new topology makes use of an efficient Packed U-Cells (PUC) structure to form the ...Multi-Cells Modular Multilevel Converters (M 3 C). It is a member of MMC root family, with extended operational capability covering therefore AC-AC and AC-DC modes of operation. A dynamic model of the PUC and the single phase M 3 C will be used along with predictive control method to validate the effectiveness of different operation modes of the converter.
Dual output PFC based luo converter fed SRM drive Anand, Aniket; Singh, Bhim; Chandra, Ambrish ...
IECON 2017 - 43rd Annual Conference of the IEEE Industrial Electronics Society,
2017-Oct.
Conference Proceeding
This paper proposes a dual output Luo converter fed SRM (Switched Reluctance Motor) drive. The proposed converter generates two symmetrical output voltages. In order to obtain PFC (power factor ...correction) operation drive is operated in DCM (discontinuous conduction mode). The current through two output inductor is discontinuous in each switching period. The converter provides high efficiency, high power density and simple structure. The regulated output voltages of proposed converter are fed to SR motor. The SR motor here is selected for the drive due to its low cost and easy construction. The variable speed operation of proposed drive is obtained by varying DC link voltage. The proposed converter configuration has controlled DC link voltage with power quality improvement at supply. Simulation results shows the PFC operation with reduced input current THD below 5%, as per the given IEEE standard.
Multilevel inverters generate low harmonic waveforms at the output, which makes them suitable for high voltage energy conversion scheme to deliver efficient high power to the loads from renewable ...energy sources like photovoltaic systems which are penetrating to the electric grid nowadays, significantly. In this paper a single-phase hybrid multilevel inverter based on cascading full bridge and half bridge cells is introduced. Moreover the associated switching technique with multicarrier PWM is designed to generate five-level voltage at the output. As well, the designed switching technique allows the capacitors of the half bridge cell to have balanced voltage despite load changes. Furthermore, this study is extended to more cells using unequal DC sources to produce more voltage levels. Simulations have been performed on two and three cells to demonstrate the efficiency of the presented cascaded inverter with equal and unequal DC sources and switching technique.
This paper presents the design of a standalone e-bike charging station powered by a hybrid renewable energy source including small wind turbines (WTs) and photovoltaic (PV) panels. In order to ...compensate the mismatch between power supply and the load demand, an energy storage system (BESS) is also included. The use of second-life lithium-ion batteries in the BESS contributes to reduce the cost of the system. A cost function composed of the total income and the cost of the BESS and the installed load charging ports is defined in order to determine the optimal second-life BESS capacity and load rating. Three constraints regarding the power of BESS, the state-of-charge (SOC) of BESS, and the loss of power supply probability are included in the optimization problem. The first and second constraints ensure that the BESS works properly, whereas the third one aims to meet the load demand. Moreover, with the lack of available historical data of the load for e-bike charging stations, a load model is developed by considering the time of the day and the weather conditions. In order to evaluate the proposed method, a case study is defined using real long-term weather data collected in Montreal, Canada and considering the design of a 1.2-kW e-bike charging station.
In this paper, a nonlinearity- compensation control scheme is used in combination with an Extended Kalman Filter estimation algorithm, in order to ensure AC current shaping and DC voltages regulation ...for a three-phase three-wire Vienna converter. This approach aims to reduce the high number of sensors, needed by the traditional nonlinear control approach, thus reducing realization costs and improving circuit reliability. For this aim, source and DC loads voltages are numerically reconstructed by an extended Kalman filter, based on the converter averaged model. Consequently, only two current sensors may be used in the circuit, versus 10 sensors for the conventional method. A multi-loop nonlinear control technique is, then, applied to the rectifier, using the estimated voltages instead of the measured ones. The measured currents and the estimated partial DC bus voltages are controlled via inner loops. The total output DC bus voltage is regulated in an outer loop, based on power balance consideration. The proposed method is experimentally verified on a 1.5 kVA prototype of the rectifier, using the DS1104 controller board of dSPACE and real-time workshop of Matlab. It is proved that the implemented nonlinear observer exhibits high estimation precision within acceptable response time, thus ensuring very satisfactory operation of the converter in steady state.
This work presents a complete procedure to compute the leakage inductance of high power density printed circuit board used in power electronic converters. By the magnetic field study, the proposed ...method gives an intuitive way to design a power PCB board by managing adequately the current densities. The proposed procedure is based on the three dimensional finite element method and the Biot-Savart integral law. By combining these two concepts, it is possible to determine a zero field path used to define the integration surface for the flux computation and consequently the leakage inductance. The method efficiency is demonstrated on a 24 V - 417 A buck converter printed circuit board used in low voltage high current applications. A detailed method used to estimates the leakage inductance during the hard switching process is also presented. Numerical as well as experimental results are shown and compared to prove the viability of the proposed approach.
This paper proposes a practical approach to the theory of instantaneous power in non-sinusoidal and unbalanced-three-phase systems. This approach is based on the symmetrical components theory in ...instantaneous state. General equations relating both the instantaneous powers and the symmetrical components in instantaneous state are developed. These developed equations are fundamental in elucidating some important characteristics of the instantaneous powers and useful to understand the control algorithms used for the UPFC and the active filtering. A control strategy based on this approach is applied to the third generation of flexible ac transmission system. A typical arc furnace and UPFC model have been implemented in digital simulator to demonstrate the capability of the UPFC to compensate all disturbances. Theory and computer simulations using Simulink of Matlab are developed to demonstrate the practicality of the approach.
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