Nowadays, the technological evolution of vehicle transmissions shows an increase of variants and concepts mostly due to electrification. Besides the development of transmissions with pure Parallel Hybrid or eCVT functionality the trend is to merge these concepts to take advantage of their beneficial characteristics. These often called Multimode-Transmissions offer high functionality but also require a sophisticated software which provides the algorithms to control all actuators and multiple power sources simultaneously to perform efficient and seamless shifts. Hence, the development of control algorithms for such advanced transmission concepts is a very complex task and therefore very cost and time intensive. That is why, early stage transmission design is typically based on simplified considerations for control analysis and construction which do not take into account complex operating scenarios such as various kinds of mode shifts under power shift constraints. This increases uncertainties and investment risk with respect to the expected system performance in real application. In this presentation IAV provides an approach for a generic shift control strategy of conventional and electrified transmissions with multiple modes. This enables detailed simulative investigations of early stage transmission concepts and provides rapid prototyping software that decreases the overall effort in the development process of real applications. This is obtained by transforming the physical model of a transmission into a virtual Dual Clutch Transmission (DCT). Based on this virtual DCT framework the control algorithms are implemented such that they are independent of the real system complexity. Consequently, the control strategy is generic for various transmission structures including multiple power sources. The presentation shows the evolution of the generic approach starting with power shift handling of conventional transmissions. Based on that, the concept can be easily extended for electrified (multimode) transmissions like Parallel Hybrids, dedicated hybrid transmissions (DHT) and eCVT. An illustrative example will be presented that shows the capability of the generic approach starting with a conventional transmission and ending up with a multimode transmission by gradually adding hybrid functionality obtained through electrification options.
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