Induction generators are increasingly being used in nonconventional energy systems such as wind, mini/micro-hydro, biogas, etc. The advantages of using an induction generator instead of synchronous generator are well known. Some of them are reduced unit cost and size, ruggedness, absence of separate DC source, ease of maintenance, self-protection against severe overloads and short circuits, etc. An attempt is made in this paper to present an exhaustive bibliography on the application of induction generators in nonconventional energy systems.

Bibliography on the application of induction generators in nonconventional energy systems

http://w3.gazi.edu.tr/~icolak/folders/SinghGK-atif.pdf

Self-excited induction generator research—a survey

This paper describes the steady-state analysis of self-excited induction generators (SEIG) using an iterative method. By considering the conductances connected across the air gap nodes, an iteration procedure is developed for the determination of the self-excited per-unit frequency, which enables the equivalent circuit to be completely solved. The proposed method involves only simple algebraic calculations, but the accuracy is good and convergence is rapid. The method is subsequently extended to include core loss effects and the analysis of SEIG with series capacitance compensation. Very good agreement between experimental and computed results has been obtained on a 2 kW laboratory machine. >

Analysis of self-excited induction generators using an iterative method

A method to analyze the steady-state open loop behaviour of a self-excited induction generator with an unregulated prime mover is presented. The proposed method needs little mathematical effort and does not require an assumption about the generator speed. The proposed approach based on nodal analysis allows one to use arbitrary functions for the torque-speed characteristic of the prime mover and for the saturation of the magnetizing inductance without complicating the solution process. It always leads to a single equation for the frequency. An example is presented demonstrating the advantages of the proposed method. The analytical results are verified by measurements. >

A technique for the steady-state analysis of a self-excited induction generator with variable speed

The performance characteristics of a cage induction machine operating as a self-excited induction generator (SEIG) in stand-alone mode are presented. A static capacitor bank is considered to self-excite the machine and to maintain its terminal voltage constant. The lagging reactive power requirement of self-excited induction generator is obtained for different load values. The effect of speed on the excitation requirement of the cage machine has also been studied. An algorithm is developed to achieve these characteristics using the Newton-Raphson method and a steady-state equivalent circuit of the machine. The developed analytical technique is extended to evaluate the number of steps of switching capacitors for loading the machine up to its full load rating while maintaining the terminal voltage within desired limits. The selection of an optimum terminal voltage corresponding to the maximum output of the machine for its optimum utilization is also made using single-variable optimization. >

Performance characteristics and optimum utilization of a cage machine as capacitance excited induction generator

A simplified model is used to describe the parallel operating characteristics of self-excited induction generators. Experimental results are presented for two single-phase machines when driven at different speeds, parallel connected to a common excitation capacitor and resistance load.

Autonomous and Parallel Operation of Self-Excited Induction Generators

Investigation of electrical breakdown in air using an image processing technique Video recordings of high-voltage breakdown tracks between electrodes in air have been analysed using an image processing technique. The paper discusses the tortuosity of the breakdown tracks, and a logarithmic distribution of track segment lengths has been found.

Investigation of Electrical Breakdown in Air Using an Image Processing Technique

The paper describes a self-excited induction generator connected through a controlled rectifier to a resistance load with no smoothing reactor. A harmonic analysis of the rectifier input current is presented. The current harmonics cause distortion of the generator voltage waveform, and the possibility of harmonic resonance exists.

The Response of a Self-Excited Induction Generator to Rectifier Harmonics

The mobility of the fruit fly Drosophila melanogaster is reduced when subjected to a 50 Hz electric field. A directional effect also occurs. A prototype electrical barrier suppresses penetration by flying at 400 kV/m, and penetration by crawling is reduced to 6% after 10 minutes at 640 kV/m.

Some Effects of Electric Fields on Living Creatures

A unified analysis of the unbalanced operation of three-limb, five-limb and three single-phase star-star connected transformers is presented. The straight forward logical mathematical procedure leads directly to the required results.

http://ije.sagepub.com/content/21/3/251.full.pdf

D. B. Watson

Papers

Autonomous and Parallel Operation of Self-Excited Induction Generators

Investigation of Electrical Breakdown in Air Using an Image Processing Technique

The Response of a Self-Excited Induction Generator to Rectifier Harmonics

Some Effects of Electric Fields on Living Creatures

Unbalanced Loading of Star-Star Connected Three-Phase Transformer