Abstract:To improve the dynamic performance of a V-type diesel engine at high altitude, the matching calculation was carried out between the diesel engine and regulated two-stage turbocharging system, and the two-stage turbines and compressors were determined. The calibration results of optimum valve opening and optimum boost pressure were achieved at all operating conditions according to the steady performance target at different altitudes. The transient simulation model was constructed, and the effect of different altitudes on the transient response characteristic of boost pressure was investigated. The openloop and closedloop control strategies were designed based on the MAP diagram of optimum boost pressure to improve the transient response of boost pressure at different altitudes. The results showed that the closedloop control strategy can achieve better transient response compared with the openloop control strategy. With the closedloop control strategy of boost pressure, the response time was reduced from 2.82s to 2.41s at the altitude of 0m. The response time was reduced from 3.20s to 2.32s at the altitude of 3000m, and it was reduced from 3.41s to 2.25s at the altitude of 4500m. The effect of different altitudes on transient response characteristic was largely weakened with the closedloop control strategy.