The operational performance of solar power tower system and photovoltaic(PV)-concentrated solar power(CSP) system integrated with supercritical carbon dioxide(S-CO_2) Brayton cycle under typical weather conditions are studied. The ability of CSP plant flexibly adjusting the power production to assist the intermittent power output of PV plant to connect to the grid is discussed. The influences of the integration of PV plant on operational performance of the CSP plant are analyzed. The thermodynamic performance of the CSP plant integrated with recompression and partial-cooling S-CO_2 Brayton cycles in different operating scenarios are compared. The results show that

the CSP plant can cooperate well with the PV plant so that the hybrid plant can achieve efficient power generation. The integration of PV plant will lead to a decrease in efficiency of the CSP plant. For example

the efficiency of the CSP plant with recompression cycle on the sunny day is reduced from 20.23% to 18.34% to assist the power generation of PV plant to connect to the grid. The CSP plant with recompression cycle performs better in the operating scenario of CSP plant generating power independently

while the CSP plant with partialcooling cycle performs better in the operating scenario of hybrid plant generating power cooperatively.