In the past decades, recent growth of renewable energy sources led to the emergence of Ditributed Energy Ressources (DERs). These low power sources are generally installed at a local level, and can be used to provide quick response to power peaks of demand in the distribution grid. The use of power converters is required to exploit power from DERs, as well as to manage its characteristics. Their connection to the grid, however, brings new issues, mainly in regards of stability and of the quality of the energy provided.
The research presented here deals with the connection of a single-phase DC/AC inverter to the grid, allowing photovoltaic panels to inject the generated power. More precisely, we will focus on establishing the control law of the inverter by ensuring its stability, control robustness, and quality of the energy produced. Performances of the designed system must then comply with actuals standards related to these issues. We will consider here a high density converter with low passive elements, and whose its switching frequency is very high, that complicates the design of its control.
Firstly, the modeling of the system will be established to be able to carry out a frequency analysis. Then, synchronization of the inverter to the grid will be ensured by a PLL, and finally, the regulation strategy ensuring stability and robustness will be presented. Particular attention will be paid to the dimensioning of control elements, where we will seek to obtain optimal values. To reach this goal, a new sizing method is proposed, which allows a user to quickly determine a new set of values, from which the quantitative behavior of the system is known. That method will be tested and validated in simulation. The results show that its behavior is consistent with the IEEE-1547 standard prevailing in North America. With the proposed dimensioning, the inverter is then able to operate in abnormal conditions of voltage and frequency, its fault response is fast, and no static errors are observed in steady state. Finally, the harmonic compensation the system will provide in the case of a polluted grid voltage will be treated, and good results will be obtained for a specific dimensioning.
| Date | 12 Aug 2019 |
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| Original language | French |
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| Awarding Institution | - École de technologie supérieure
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| Supervisor | Handy Fortin Blanchette (Supervisor) |
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Bruyant-Rozoy, C. (Author),
Fortin Blanchette (Supervisor),
12 Aug 2019Student thesis: Master's thesis › Master in Engineering: Electrical Engineering