Energy Method for Controlling a Traction Electric Drive

The aim of this study was to develop algorithms for controlling an automobile electric drive based on the equations for the instantaneous balance of the active and reactive power of induction (IM) and synchronous machines (SM). We considered the information properties of the first harmonics of the three-phase voltage between the inverter and electrical machines. Our examination showed that processing the primary data of current and voltage sensors according to the algorithms of the generalized energy flow allows us to obtain complete information on the parameters of the three-phase circuit in the form of generalized state variables. We further investigated the metrological support of a traction electric drive, which makes it possible to complete a wide range of control, diagnostics, protection, and backup tasks. We present energy models of IMs and SMs obtained by summing the instantaneous power of the individual phases into a single energy stream. We show that taking the impact of the magnetic field energy (magnetization energy) and the kinetic energy of the load into account allows us to analyze the dynamics of electrical machines as second- and third-order nonlinear control objects. The article contains a general solution of the algorithms for controlling the basic variables of electrical machines: the amplitude of a three-phase voltage and the electromagnetic moment. The analytical equations of the algorithms are presented as the sum of two terms: the first accounts for the dynamics of the mechanical load and the second for the dynamics of the electromagnetic system of electrical machines. This article provides a brief review of our publications containing the results of adapting the general solution in accordance with the criteria of energy efficiency, quasi-independent excitation and minimizing the electrical heating of the IM rotor, and adaptive control of the SM. We detail an innovative strategy for controlling a traction electric drive based on the use of the energy models of IMs and SMs.