The authors discuss high-voltage power conversion. Conventional series connection and three-level voltage source inverter techniques are reviewed and compared. A novel versatile multilevel commutation cell is introduced: it is shown that this topology is safer and more simple to control, and delivers purer output waveforms. The authors show how this technique can be applied to either choppers or voltage-source inverters and generalized to any number of switches.<<ETX>>

Multi-level conversion : high voltage choppers and voltage-source inverters

A robust predictive current control algorithm for permanent magnet synchronous motor (PMSM) drives is proposed. The robust controller adopts an incremental system model, thus can operate without knowing the rotor flux, which is a pivotal parameter in conventional dead-beat control. The incremental model is easy to implement compared with relevant flux identification algorithms or observers. The robust controller adopts an extended state observer (ESO) to enhance inductance robustness to cater for the divergence caused by stator inductance mismatch. The inductance mismatch uncertainties can be estimated and compensated by ESO. Conventional dead-beat control is modified for multistep prediction to achieve high disturbance rejection. Detailed stability and disturbance rejection analysis are conducted theoretically, and rules on parameter selection are given. Comparative simulations and experimentations verify the effectiveness and superiority of proposed robust control over conventional dead-beat control.

Flux Immunity Robust Predictive Current Control With Incremental Model and Extended State Observer for PMSM Drive

In this study, the effect of magnet temperature on speed, current and torque in permanent magnet synchronous motor was investigated. First, the demagnetization curves of Neomag S 28VC class magnet related to different temperatures, which was used for MCS06C41 coded motor of Lenze Company, were approached. A mathematical expression was achieved to calculate the remanence value for any temperature using these curves and curve fitting method. Then, a simulation was made according to the field oriented vector control method in MATLAB/Simulink using real motor and driver parameters. The mathematical expression that gives the change of magnetic flux related to the temperature influence was included in the modelling. In this way, the change of the speed, current and torque for different magnet temperatures were made observable. Six simulations were made with 25°C increase from 25°C to 150°C to observe the effect of the temperature on the motor much better. The simulation results have clearly demonstrated the effects of the increase of the magnet temperature especially on the current and torque.

The effect of magnet temperature on speed, current and torque in PMSMs

The proposed proposal basically concentrate on energy efficient and cost effective model construct an automatic UPS monitoring and controlling system , with the context of PDA’s to machine level and machine level to PDA’s.RF is the essential information based communication system now a days i.e. Bluetooth/ZigBee/Wi-Fi . IoT based UPS provides the balancing tradeoff between monitoring and controlling the system remotely in order to increase the energy efficiency and production rate. Proposed system automatically monitor the 4 parameters ,i.e current ,voltage, temperature, power which runs on each UPS. During the drain out or worn-out if any of the pa-rameters like voltage andcurrent decreases from the ideal conditions then this will be monitored automatically and the values will be displayed on android app application and and uploaded to the cloud(IoT).The breakdown conditions of UPS will be notified to the chief engineer,supervisor and control room through SMS and IoT.

/pdf/performance-monitoring-of-ups-battery-using-iot-1ouv65p64x.pdf

Performance monitoring of UPS battery using IoT

There has been a lot of progress going on in field of solar inverters. transformerless inverters has ben the most research area in recent time. For the operation of inverter in stand alone condition it is necessary to make sure that the control of the inverter is taken in account for maintaining the different operation parameters and making the system more safe and stable. This paper presents a comparative analysis of Highly Efficient and Reliable Inverter Concept (HERIC) inverter which is being controlled by hybrid controller. Stability testing of the HERIC inverter is performed based on load varying condition using Fuzzy-Proportional Integral Derivative (PID) and ANFIS-PID controller. Numerous different requirement is taken into consideration and analysis is carried out on basic of settling time and harmonic distortion present. At the end the experimental result conclude that system is running accurately with low settling time and harmonics distortion of less then 3.7%.

Hybrid Voltage Control for Stand Alone Transformerless Inverter

In a grid connected photovoltaic system, the main aim is to design an efficient solar inverter with higher efficiency and which also controls the power that the inverter injects into the grid. The effectiveness of the general PV system anticipate on the productivity by which the direct current of the solar module is changed over into alternating current. The fundamental requirement to interface the solar module to the grid with increased productivity includes: Low THD of current injected to the grid, maximum power point, and high power factor. In this paper, a two stage topology without galvanic isolation is been carried out for a single phase grid connected photovoltaic inverter. The output from the PV panel is given to the DC/DC boost converter, maximum power point tracking (MPPT) control technique is being used to control the gate pulse of the IGBT of boost converter. The boosted output is fed to the highly efficient and reliable inverter concept (HERIC) inverter in order to convert DC into AC with higher efficiency.

Design of HERIC configuration based grid connected single phase transformer less photovoltaic inverter

In this paper; Design and development of control circuit algorithm of 3-Φ Voltage Source Inverter (VSI) using Unipolar Sinusoidal Pulse Width Modulation (SPWM) techniques is proposed using STM32F407VGTx discovery board interfaced with MATLAB Simulink Environment. For implementing 3-Φ VSI; this method is most useful as it will eliminate complexity of control circuit algorithm occurred due to analog circuit; reduces cost; size of filter required and improved overall inverter efficiency. Pulse width modulated voltage source inverter is preferred for high performance AC drives. The proposed control scheme and the result obtained by embedded simulations interfaced with STM32F4 microcontroller are presented and discussed. A simple hardware implementation is proposed and experimental results of SPWM based VSI are also shown. The Simulation results of the proposed scheme have excellent performance and compared with hardware results.

Implementation of SPWM technique for 3-Φ VSI using STM32F4 discovery board interfaced with MATLAB

This paper describes the closed loop space vector modulation strategy for Active Front End Converter (AFC). Low value of Power factor and excessive harmonic content are major disadvantages of conventional converter. To alleviate this problem, Carrier-Based-Sinusoidal Pulse Width Modulation (CB-SPWM) can be implemented in PWM converter; Narrow range of linear operation of converter is limitation of it. Because of which SVPWM is preferred choice. High voltage utilization, low harmonic content, low switching losses and simple hardware circuit are avail features of it. The principle of seven-segment switching is presented Simulation of front-end converter involving closed loop control is carried out in MATLAB/SIMULINK environment. for steady state and dynamic loading conditions. Irrespective of load conditions, Unity power factor is obtained. fixed d.c link voltage for dynamic conditions is obtained proving good voltage regulation. Total Harmonic Distortion (THD) of the supply current is in the specified limits provided by IEEE 519-1992.

Close loop control of three phase Active Front End Converter using SVPWM technique

This Paper presents investigation of design parameter, performance parameter and mathematical modeling of Permanent Magnet Synchronous Motor (PMSM) drive. For speed control of PMSM Field orientation Control(FOC) technique is used. For control algorithm, hysteresis current control method is employed for providing constant torque operation on load side. The aim of the PMSM drive is to have speed control over wide speed range with constant torque operation. Simulation results shows that the speed and current controller has a good dynamic response. Simulation has been done in MATLAB Simulink environment. The simulation consists of all realistic components and mathematic equation that enable the calculation of current and voltage in different parts of control algorithm. Hardware circuit is implemented using STM 32F processor and investigate the result obtain using MATLAB Simulink and hardware results.

Investigation of design, analysis and performance of hysteresis current control PMSM drive

This paper presents the simulation of cascaded multilevel inverter fed induction motor drive. The poor quality of voltage and current of a conventional inverter fed induction machine is due to the presence of harmonics and hence there is significant level of energy losses. To obtain high quality sinusoidal output voltage with reduced harmonics, multi carrier based Sinusoidal pulse width modulation(MSPWM) control scheme is proposed for cascaded H bridgemultilevel inverter. The field orientation control techniqueis used to control the speed of induction motor by controlling the quadrature axis current using PI speed regulator. The proposed system is an effective replacement for the conventional method which produces high switching losses results in poor drive performance. The simulation results reveal that the proposed circuit effectively controls the motor speed and enhances the drive performance through reduction in total harmonic distortion (THD). The effectiveness of the system is verified through simulation using PSIM Simulink software.

/pdf/analysis-and-simulation-of-multi-level-inverter-fed-3bxxin5fvt.pdf

Divyesh J. Vaghela

Papers

Design of HERIC configuration based grid connected single phase transformer less photovoltaic inverter

Implementation of SPWM technique for 3-Φ VSI using STM32F4 discovery board interfaced with MATLAB

Close loop control of three phase Active Front End Converter using SVPWM technique

Investigation of design, analysis and performance of hysteresis current control PMSM drive

Analysis and Simulation of Multi Level Inverter Fed Induction Motor Drive