Operation in Distributed Power Generation Scheme with Transition of Control Between Stand-Alone and Grid Connected Modes

Operation in Distributed Power Generation Scheme with Transition of Control Between Stand-Alone and Grid Connected Modes

Rupa Mishra Tapas K. Saha 

Department of Electrical Engineering, National Institute of Technology, Durgapur 713209, India

Corresponding Author Email: 
8 May 2018
27 June 2018
30 June 2018
| Citation



This paper presents flexible control strategy of a squirrel cage induction generator (SCIG) featuring transition between stand-alone and grid-connected systems. The consistent load voltage supply in both the modes is ensured with smooth transition of the controls of stand-alone and grid connected modes. In the proposed technique, dc bus voltage controller of the stand-alone system is maintaining the input power same as the demand by controlling the speed. On the other hand, the same dc bus voltage controller of the grid-connected system maintains the output power at same level as input power. The transient performances of different variables of the system, during this flexible control are found to be satisfactory and THD remains within 3% throughout the study. The flexible control for both the modes is presented for the first time in available literature. The model is helpful for interfacing into wind-energy system.


Induction generator, current control, voltage control, Pulse Width Modulation (PWM), Squirrel cage induction generator (SCIG), Total Harmonics Distortion (THD)

1. Introduction
2. System Configuration
3. Control Strategy
4. System Description
5. Results and Discussion
6. Conclusion

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