Application No./Patent No.: 2018100761208 Application date: January 26, 2018.
Inventor/Designer: Peng Zhihui, Zhong Rong, Li Kai.
The invention provides a flow control method and a flow control method. Firstly, based on the principle of small-signal disturbance modeling, a small-signal disturbance △F is applied to the pump operating frequency at any relative steady-state time of the flow control system, and the relationship between the corresponding flow change value △q(t) and the relative steady-state pressure value p is obtained. Based on the definition of time constant, the time constant of △q(t) is obtained, and then the pressure p is obtained. Secondly, based on the data of output flow Q and head (or pressure) P, according to the translation characteristics of the head characteristic curve of the variable frequency speed regulating pump, the head characteristic curve of each pump passing through the point (Q, P) on the Q-H plane and the intersection point between the head curve and the corresponding high efficiency interval boundary are obtained. Finally, according to the positional relationship between the high efficiency interval of each pump and (q, p) and the intersection point, the performance parameters of high efficiency operation are obtained, and then the pump with the best performance parameters is selected to work to ensure the high efficiency operation of the flow control system. According to the invention, the high-efficiency operation control of the flow control system can be realized without a pressure detection sensor and an auxiliary circuit, so that the time and cost required for installation and debugging of the pressure sensor and the auxiliary processing circuit are saved, the system structure is simpler, the system cost is lower, the operation efficiency is higher, the service life and reliability of the system are improved, and reliable guarantee is provided for safe and efficient operation of the flow control system.
