Dry Type Engine Clutch Control for a Parallel HEV at Launch Start Condition
A parallel type HEV has a power transfer device that is constructed by clutches and the device which is located between engine flywheel and electric traction motor is called 'Engine Clutch' When a traction motor of could not generate power to move, the HEV must launch only by engine power. In this situation the slip speed control and transmitted torque control are very important. In this study control strategies of dry type engine clutch is proposed to satisfy desired clutch engagement time and required torque at launch start condition. A dynamic model of a parallel type HEV driveline is constructed to apply the method proposed.
Model Reference Adaptive Control during Mode Transition of a Parallel Hybrid Electric Vehicle
Model reference adaptive control (MRAC) is proposed for torque coordination in order to improve dynamic performance during the mode transition of a parallel hybrid electric vehicle. Although model reference control (MRC) has been shown to be effective in controlling the mode transition, difficulties arise in application because the parameters of the reference model is unknown and time-varying. Small error of the parameter estimation may lead to instability of the MRAC system. With a reference model whose parameters are tuned by an estimator, the stability condition of the MRAC is derived. Thereafter, an adaptive law is designed to tune the feed-forward and feedback gains to satisfy the stability conditions for the mode transition. Simulation results show that the proposed MRAC can be stable even when the estimation error is large, and performs well under different road conditions.
Numerical Simulation of Thermal Sensitivity for Explosives
In order to compare the thermal sensitivity of several typical explosives, this article solved numerically one-dimensional transient heat conduction equation including thermal decomposition for explosives with finite difference method. The explicit difference equations under different boundary conditions were established, and the corresponding stability criterion was derived. The ignition times for typical explosives were calculated, which was used to evaluate thermal sensitivity of explosives.