Diversity Diagnostic for New FPGA Based Controller of Renewable Energy Power Plant

The renewable energy plants tend to require the performance improvement and the scale extension continuously, and also tend to be installed in inconvenient locations for maintenance. Under these background, the control systems of them require high reliability and maintenance-free. In recent years, from the view point of heat generation and system inheritability, the construction of the control system with FPGA (Field Programmable Gate Array) is focused. To design the control system, redundancy with diversity is expected to be the key function to improve reliability and safety of the control, under the consideration of reduction of development cost and production cost. This paper proposes a methodology to generate diverse FPGA circuitries by the Technology-Mapping without both algorism diversity and code diversity. The diversity of the redundant control system is realized by different circuit structures in FPGA with the Technology Mapping and prove-in-use tools. From the simulation of real FPGA implementation setting, it is clarified that the diverse pair of FPGA circuitries improves the error detection rate and the common cause failure fraction. Moreover, it is also clarified that the proposed methodology provides the improvement of MTBF and Safety Integrity level (SIL) of control systems. Therefore, it is revealed that the proposed methodology realizes the new FPGA controller which is suitable for the redundant control system in renewable energy plants.