Session: 06-01 Innovative Combined Cycle

Paper Number: 82494

82494 - Gas Turbine Combined Cycle Range Enhancer - Part 1: Cyber-Physical Setup 

Natural gas-fired combined cycles (CCGTs) are playing a fundamental role in the current energy transition phase towards sustainable power generation. This scenario is characterized by strong requirements in terms of grid flexibility and non-dispatchable renewable penetration. The competitiveness of a CCGT in future electrical networks will thus be strictly related to its capability to successfully compensate for both the discontinuous demands of the ancillary market and the renewable fluctuating production. This can be possible by enhancing the power generation flexibility and extending the operative range of the plant (in particular, the maximum power and the minimum environmental load).

The European H2020 project PUMPHEAT aims at achieving this goal, and within this framework, a test rig to investigate gas turbine inlet conditioning techniques was developed at the laboratory of the University of Genoa, Italy. The plant is composed by three key components: a 100 kWel micro gas turbine (mGT), a 10 kWel butane-based heat pump (HP), and 100 kWh latent heat cold thermal energy storage (TES). The physical test rig is virtually scaled up, through a cyber-physical approach, to emulate a real 400MW combined cycle, a 3.5 MWel HP, and a 10 MWh TES.

The high-level control logics determining the daily operation of the plant are setup referring to the Italian energy market scenario, including fluctuations in power demands related to discontinuities on the electric market and renewable power generation.

The HP and the TES are used to control the mGT inlet air temperature and thus enhancing the operational range of the plant. In particular, cooling the air flow with the HP or the TES allows to increase the maximum power generated by the mGT, while heating the air flow with the HP reduces its power output and enhances the part-load efficiency.

The advantages of a test rig where a mGT is used for studying CCGT range extension strategies and flexibility options, apart from the savings in terms of capital costs, are also related to the possibility to perform accelerated tests and to emulate multiple conditions in short time windows.

This article aims to introduce the facility, the real-time bottom cycle model, and the three-levels model predictive control system that regulates the operation of the cyber-physical plant. The regulating strategy for the main equipment is described in detail, and the behavior of the rig is analyzed, with a particular focus on the influence of the environmental conditions. The main components of the plant are tested in stationary conditions and their performance is presented.

Presenting Author: Tommaso Reboli University of Genoa

Presenting Author Biography: Research fellow, Department of Mechanical, Energy, Management and Transport Engineering, University of Genoa, Italy.<br/>Ph.D. on the topic of Wave Energy Converters (2020).<br/>Involved in different projects, responsible for experimental activities of H2020 EU funded Pump Heat project.

Authors:

Tommaso Reboli University of Genoa
Marco Ferrando University of Genoa
Luca Mantelli University of Genoa
Lorenzo Gini University of Genoa
Alessandro Sorce University of Genoa
Jose Garcia KTH Royal Institute of Technology
Rafael Guedez KTH Royal Institute of Technology