Permanent Magnet Radial Ring on Dynamic Characteristics and Energy Loss of High-speed On-off Ball Valve in Clutch Shift System

A high-speed on-off ball valve with fast transient response is a crucial hydraulic element of the clutch shift system, which is provides exact and reliable control of the shift. In the present investigation, an analysis of the transient response and thermal loss characteristics of the novel high-speed on-off ball valves (HSBVs) with a permanent magnet radial ring was conducted using the finite-element method (FEM). The impacts of permanent magnet radial ring on the transient characteristics of HSBV have been inspected. The simulation results indicated that the radiation ring changes the magnetic induction intensity inside the ball. Compared with the conventional HSBV, the transient response time of a novel HSBV with permanent magnetic ring is shortened from 3.75 ms to 1.35 ms, which is 64% shorter. Moreover, the novel HSBV improves the utilization ratio of mechanical energy from 14.6% to 27.8% and effectively reduces the iron loss from 37.3% to 28.6%. The analysis also confirmed that the increase of thickness and length of the radiation ring are positively related to the improvement of dynamic response of HSBV, which could enlarge the transformation ratio of mechanical energy and weaken the eddy current loss. The influence of coercivity of permanent magnet ring with five different materials was also analyzed. It was noticed that the HSBV with permanent magnet ring made by N45H has the fast dynamic response because of its high coercivity.