Modeling and simulation of a blood pump for the development of a left ventricular assist system controller

A mathematical model describing the pressure-volume relationship of the Nov acor left ventricular assist system (LVAS) was developed. The model consist ed of lumped resistance, capacitance, and inductance elements with one time -varying capacitor to simulate the cyclical pressure generation of the syst em. The ejection and filling portions of the pump cycle were modeled with t wo separate functions. The corresponding model parameters were estimated by least squares fit to experimental data obtained in the laboratory. The mod el performed well at simulating pump pressure of operation throughout the f ull cycle. Computer simulation of the pump with a cardiovascular model demo nstrated the interaction between the LVAS and the cardiovascular system. Th is model can be used to incorporate on-line cardiovascular parameter estima tion and to design a new controller for the LVAS.