CONCLUSION

This thesis proposes distributed reactive power support with a CVR algo- rithm that uses two-way communication provided by smart-grid technology. The solutions are obtained from SQP to minimize the deviation from the control voltage level. The distributed voltage control scheme using reactive power support from PV grid-tie inverters is tested in the modied IEEE- 13 node feeder system. The results show that voltage reduction with dis- tributed reactive power support in the given system is feasible and benecial. The proposed method not only solves under/over-voltage issues locally but also attains signicant savings in energy while reducing system feeder losses. Smart-grid-enabled distributed reactive power support ultimately ensures a better power factor at the substation and improves the feeder voltage prole. Widespread such devices would enable system operators to gain control over voltages in distribution levels; furthermore, it would also reduce the reactive power demand from generators in the transmission systems while increasing the real power production capability. Smart-grid-enabled distributed reactive power support shows the possibility of increasing overall system eciency, both in transmission and distribution systems, while improving the voltage stability and system reliability.

5.1 Future Work

Although this control scheme can be remotely implemented in distribution systems, communication integrity, system security, and consumer condence remain as challenges to overcome. For future work, the current method will be incorporated with a distributed control mode combining decentral- ized and centralized schemes. The distributed control scheme will not only determine the amount of reactive power required at each node to achieve

certain objective goals, but also reduce communication costs since the nu- merous distributed resources do not have a direct communication link with a higher level control. Moreover, the interactions between the cybersecurity and power system will be examined to ensure a smarter future power grid.

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