Structure-preserving model reduction with applications to power system dynamic equivalents

Consider systems that have an intrinsic mathematical representation of the form: , where is the th derivative of , and . The matrices may possess certain properties. The problem is to construct a reduced model having the same form with corresponding matrices of smaller dimension and possessing the same properties. An algorithm for this structure-preserving model reduction is presented. An algorithm for constructing an approximate reduced model, called -structure preserving reduced model is also presented, together with the error bounds. The application of the method to power system dynamic equivalents is described.