The HAT cycle has aroused considerable interest. This paper emphasized the right representation of humidifier that is a key unit in the HAT cycle. An improved superstructure for the HAT cycle was then proposed to improve the thermodynamic performance working at a wide range of pressure ratio. The configuration and parameters were optimized simultaneously. The results revealed that the optimal system can reach the minimum exergy losses match. The artificial assumptions based on intuition and locally thermodynamic analyses by previous researchers are harmful to the efficiency of HAT, and also mislead the frame of HAT. The insights in this paper can provide a basis for system match and unit design for the development of HAT power generation system.