The advancement on penetration of renewable energy sources in the power system is, in part, tied to the
current control of grid-connected LCL-filtered voltage source converters. A challenge is current control
with the addition of the LCL-filter resonance, which interacts with the digital converter-control switching
action and creates the possibility for instability. In certain scenarios, active damping is needed to
stabilize the system and ensure robust performance in steady-state and dynamic response. Another approach
is detailed in this paper where a hybrid linear and nonlinear controller is implemented to ensure
the dynamic current control performance. This is done by combining a linear outer-loop Proportional
Resonant current controller with a nonlinear inner-loop Model Predictive voltage controller to replace
the fixed switching-frequency Pulse Width Modulator. This allows for easy compensation of nonlinear
effects, such as time delays and provides the controller with the ability to prioritize the dynamic performance
during step changes. The details for implementing this control structure are provided, along with
a discussion of the advantages, and guidelines for the design procedure of the hybrid control structure.
Simulation results and experimental measurements are provided to illustrate the control performance and
validate the proposed method. As a conclusion, the control method as a whole is discussed in relation to
the presented work and further research options.
| Period | 19 Sept 2018 |
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| Event title | EPE'18, 20th European Conference on Power Electronics and Applications (EPE'18 ECCE Europe) |
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| Event type | Conference |
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| Conference number | 20th |
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| Location | Riga, LatviaShow on map |
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| Degree of Recognition | International |
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- Model Predictive Control
- Grid-Connected Converter
- Voltage-Source Converter
- Nonlinear Control
- Active damping