Temperature and frequency dependence of electrical iron effects on electromagnetic characteristics of high-speed solenoid valve for common rail injector

In our study, the B–H magnetization curves at temperatures between 16 and 150∘C and frequencies between 50 Hz and 1000 Hz were measured to analyse the effect of temperature and frequency on the magnetization characteristics of electrical iron DT4C. By researching a high-speed solenoid valve (HSV) f or a common rail injector, the temperature and frequency dependence of DT4C and their effects on the electromagnetic force and dynamic response of a HSV were obtained. The research results showed that an increase in temperature could decrease the magnetic flux density; however, the decrease was not apparent. The effect of temperature on the relative permeability depended on the range of magnetic flux density B. The temperature dependence of DT4C was weak in the temperature range of 16--150∘C. This stability of magnetic characteristic of DT4C ensures that the dynamic response of a HSV could be maintained well for a common rail injector. Magnetization frequencies had a significant influence on the magnetization of DT4C. An increase in the frequency would delay the transition to the saturation magnetic flux density Bs. The effect of frequency on the electromagnetic force became increasingly significant as the driving current increased. In a frequency range of 50–200 Hz, the opening response time of a HSV could be maintained well. When the frequency was higher than 200 Hz, the opening time increased significantly with the frequency raised from 200 Hz to 1000 Hz, furthermore, the HSV was out of control and closed ahead of time.