Hybrid models are those containing continuous and discontinuous behaviour. In constructing dynamic systems models, it is frequently desirable to abstract rapidly changing, highly nonlinear behaviour to a discontinuity. Bond graphs lend themselves to systems modelling by being multi-disciplinary and reflecting the physics of the system. One advantage is that they can produce a mathematical model in a form that simulates quickly and efficiently. Hybrid bond graphs are a logical development which could further improve speed and efficiency. A range of hybrid bond graph forms have been proposed which are suitable for either simulation or further analysis, but not both. None have reached common usage.ududA Hybrid bond graph method is proposed here which is suitable for simulation as well as providing engineering insight through analysis. This new method features a distinction between structural and parametric switching. The controlled junction is used for the former, and gives rise to dynamic causality. A controlled element is developed for the latter. Dynamic causality is unconstrained so as to aid insight, and a new notation is proposed. ududThe junction structure matrix for the hybrid bond graph features Boolean terms to reflect the controlled junctions in the graph structure. This hybrid JSM is used to generate a mixed-Boolean state equation. When storage elements are in dynamic causality, the resulting system equation is implicit.ududThe focus of this thesis is the exploitation of the model. The implicit form enables application of matrix-rank criteria from control theory, and control properties can be seen in the structure and causal assignment. An impulsive mode may occur when storage elements are in dynamic causality, but otherwise there are no energy losses associated with commutation because this method dictates the way discontinuities are abstracted. ududThe main contribution is therefore a Hybrid Bond Graph which reflects the physics of commutating systems and offers engineering insight through the choice of controlled elements and dynamic causality. It generates a unique, implicit, mixed-Boolean system equation, describing all modes of operation. This form is suitable for both simulation and analysis.
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机译：混合模型是包含连续和不连续行为的模型。在构造动态系统模型时，经常需要将快速变化的高度非线性行为抽象为不连续性。键合图具有多学科性并反映了系统的物理特性，因此很适合进行系统建模。一个优点是，他们可以快速有效地模拟形式生成数学模型。混合键图是一种逻辑发展，可以进一步提高速度和效率。已经提出了一系列混合键图形式，它们适合于模拟或进一步分析，但不能同时适用于两者。没有一个通用方法。 ud ud在此提出了一种混合键图方法，该方法适用于仿真并通过分析提供工程见解。这种新方法的特点是结构和参数切换之间的区别。受控结用于前者，并引起动态因果关系。为后者开发了一个受控元件。动态因果关系不受限制以帮助洞察，并提出了一种新的表示法。 ud ud混合键图的结结构矩阵具有布尔项，以反映图结构中的受控结。该混合JSM用于生成混合布尔状态方程。当存储元素处于动态因果关系时，得出的系统方程是隐式的。 ud ud本文的重点是模型的开发。隐式形式允许根据控制理论应用矩阵秩准则，并且可以在结构和因果分配中看到控制属性。当存储元素处于动态因果关系时，可能会发生脉冲模式，但否则不会存在与换向相关的能量损失，因为此方法指示了抽象不连续性的方式。因此，主要贡献是混合键合图，它反映了换向系统的物理特性，并通过选择受控元素和动态因果关系提供了工程见识。它生成一个唯一的，隐式的混合布尔系统方程，描述所有操作模式。此表格适用于仿真和分析。
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