Page 234 - Advances in Renewable Energies and Power Technologies

CHAPTER

Flexible Power Control

of Photovoltaic Systems 6

Frede Blaabjerg, Ariya Sangwongwanich, Yongheng Yang
Department of Energy Technology, Aalborg University, Aalborg, Denmark

CHAPTER OUTLINE

1. Introduction ....................................................................................................... 207
2. Demand to Grid-Connected PV Systems................................................................ 209
2.1 Overloading of the Grid (Overvoltage) During PV Peak-Power
Generation Period ............................................................................... 209
2.2 Grid Voltage Fluctuation Because of Intermittency of PV Energy.............. 210
2.3 Limited-Frequency Regulation Capability to Stabilize the Grid During
Frequency Deviation............................................................................ 210
3. Possible Solutions for Flexible Power Control of PV Systems ................................ 211
3.1 Integrating Energy Storage Systems ...................................................... 211
3.2 Installing Flexible Loads ...................................................................... 212
3.3 Modifying the Control Algorithm of the Power Converters ........................ 213
4. Power Converter Technology and Control for PV Systems...................................... 214
4.1 System Diagram of Grid-Connected PV Systems..................................... 214
4.2 Control Structure of Grid-Connected PV Systems.................................... 217
4.3 Maximum Power Point Tracking Algorithms ........................................... 218
5. Flexible Active Power Control of PV Systems ....................................................... 220
5.1 Power-Limiting Control Algorithm ......................................................... 220
5.2 Power Ramp-Rate Control Algorithm ..................................................... 221
5.3 Power Reserve Control Algorithm .......................................................... 222
6. Summary ........................................................................................................... 225
References ............................................................................................................. 226

1. INTRODUCTION
As a result of environmental and CO 2 emission concerns, renewable energy sources
have gained more and more attention worldwide. Several countries have set an ambi-
tious goal for energy production capacity concerning renewable energy sources. As
a main market share, the European Council targets 30% of renewable energy by
2030 [1]. With the same milestone, Germany plans to achieve 18% of renewable en-
ergy for gross energy consumption [2]. Denmark has also set a goal to be
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Advances in Renewable Energies and Power Technologies. https://doi.org/10.1016/B978-0-12-812959-3.00006-X
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