S. Ganesh Kumar

Sensorless load torque estimation and passivity based control of buck converter fed DC motor.

Passivity based control of DC motor in sensorless configuration is proposed in this paper. Exact tracking error dynamics passive output feedback control is used for stabilizing the speed of Buck converter fed DC motor under various load torques such as constant type, fan type, propeller type, and unknown load torques. Under load conditions, sensorless online algebraic approach is proposed, and it is compared with sensorless reduced order observer approach. The former produces better response in estimating the load torque. Sensitivity analysis is also performed to select the appropriate control variables. Simulation and experimental results fully confirm the superiority of the proposed approach suggested in this paper.

Operation of self-excited induction generator through Matrix Converter

This paper aims at obtaining fixed output voltage of frequency 50 Hz to the load by a self excited induction generator (SEIG) employed in wind energy conversion system (WECS). The output voltage of a SEIG is a function of wind turbines speed, which varies with wind velocity. Due to the variation in shaft speed of the wind turbine, the output voltage and frequency of doubly fed induction generator (DFIG) will vary. In this paper, a new WECS is proposed in which the conventional PWM AC/ DC/ AC converter is replaced by a matrix converter (MC) topology and the DFIG machine is replaced by a low cost squirrel cage induction generator. MC eliminates bulky DC link capacitor, provides bi-directional power flow capability, independent control on the output voltage magnitude, frequency and phase angle as well as the input power factor. Space vector pulse width modulation (SVPWM) technique is used for controlling MC in such a way that output load voltage and frequency is kept constant for all wind velocities. The SVPWM technique provides higher voltage transfer ratio without lower order harmonics. SVPWM is digitally implemented using DSP processor (TMS320 F2407A). Switching times are pre-calculated offline. Semi soft commutation procedure for safe switching control of MC switches is also presented.

Soft sensing of speed in load torque estimation for boost converter fed DC motor

In this paper, Soft sensing of speed in an online Algebraic Approach (SAA) is presented for the estimation of load torque and thereby to control the speed of DC motor using exact tracking error dynamics passive output feedback (ETEDPOF) control law. The superiority of SAA is compared with Soft sensing of speed in Reduced Order Observer (SROO) approach. Sensitivity analysis is also performed to choose the appropriate control variables. Simulation and experimental results fully confirms the features of soft sensing of speed.

Microgrid energy management and control: Technical review

Microgrid has been widely used as an approach for the integration of distributed energy sources with energy storage systems in the electric network. It is developed as a building block for the smart grid system. Different aspects of microgrid are discussed in this paper. Brief descriptions about different types of control techniques for microgrid control are provided. Further energy management schemes, future trends and challenges of Microgrid also described.

Cost effective control of a partially flat boost converter fed DC motor

In this paper, the load torque is measured using sensorless online algebraic approach (SAA) and sensorless reduced order observer (SROO) scheme without torque as well as speed sensor. The measured torque is used in controlling the speed of DC motor connected through a partially flat boost converter using the exact tracking error dynamics passive output feedback (ETEDPOF) control law. Further, SAA is compared with SROO scheme for frictional, propeller, fan type, and unknown load torques. The results obtained confirm the reduction in cost of due to the indirect measurement of load torque and speed.

Sliding mode control of electric drives/review

This paper deals with the basic concepts of sliding mode control of electric drives. Further, the features of sliding mode control are discussed. The discussions mainly on types of sliding mode control, order reduction, decoupling principles, disturbance rejection, insensitivity to parameter variations, and implementation in power converters, electric drives. In continuation of that recent trends in sliding mode control is also discussed.

A review on multilevel inverter with reduced switch count

Multilevel inverters have made another surge of enthusiasm for industry and investigation. While the set up topologies have wound up being an achievable choice in a broad assortment of high-power medium-voltage applications, there has been a dynamic energy for the advancement of fresher topologies. Decrease in general part considers contrasted with the traditional topologies has been a vital objective in the as of late presented topologies. In this paper, a segment of the starting late proposed multilevel inverter topologies with decreased power switch number are studied and evaluated. This paper will serve as an associate and a redesign with these topologies, both to the extent of subjective and quantitative parameters.