An organic Rankine cycle system

Abstract

The invention relates to an organic Rankine cycle system, which includes a working medium pump, an evaporator, a condenser and a cooling pump, and also includes a working medium pump speed control loop and a cooling pump speed control loop. The working medium pump speed control loop includes sequentially connected The first deviation calculation block, the cascade adjustment main adjustment PID adjustment block, the second deviation calculation block and the cascade adjustment sub-regulator PID adjustment block, the first deviation calculation block inputs the heat source outlet temperature of the evaporator and the heat source outlet temperature set value , the second deviation calculation block inputs the output of the cascade adjustment main adjustment PID adjustment block and the working medium outlet pressure of the evaporator, the cascade adjustment sub-regulator PID adjustment block is connected with the working medium pump, and the cooling pump speed control loop includes the third deviation The calculation block and the third PID adjustment block, the third deviation calculation block inputs the cooling water flow set value and the inlet cooling water flow of the cooling pump, and the third PID adjustment block is connected with the cooling pump. Compared with the existing technology, the heat recovery and thermal efficiency are improved, and the net output power is increased.

Description

technical field [0001] The invention relates to the technical field of organic Rankine cycle system control, in particular to an organic Rankine cycle system. Background technique [0002] The Organic Rankine Cycle (ORC) is widely used in the fields of low-quality thermal energy utilization and waste heat recovery. The net power output of an ORC system depends on both heat recovery and thermal efficiency, both of which are affected by heat exchanger pinch points. The pinch point of the heat exchanger refers to the position where the temperature difference between the hot and cold fluids on both sides of the heating surface is the smallest, and the temperature difference at this point is called the pinch point temperature difference. If the pinch point temperature difference is too small, the heat recovery will be reduced, and if the pinch point temperature difference is too large, the thermal efficiency will be reduced. Existing studies have shown that the temperature diff...

AI Technical Summary

Problems solved by technology

Experimental and model calculation results show that these control methods will affect the pinch point, thereby affecting the heat recovery, thermal efficiency and net output power

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