Electric vehicle fast charging control method and system based on virtual synchronous motor

Abstract

The invention relates to an electric vehicle fast charging control method and system based on a virtual synchronous motor. Reactive power, a voltage amplitude and an angular frequency of a rectifier are calculated based on a voltage / current output by a synchronous power grid; the actual charging power of a power battery is determined based on a droop relationship of a charging mode; a three-phasecurrent reference instruction is formulated according to obtained parameters so as to control the voltage of a direct-current bus; and an electric vehicle is controlled to be quickly charged based onthe direct-current bus voltage and a pulse signal generated by a resonance current of a full-bridge resonance LLC converter. According to the scheme, virtual synchronous motor control and constant-current quick charge control are achieved through the rectifier, and good coordination is achieved. The front-stage circuit and the rear-stage circuit of the system are different in control target and clear in division of labor. The requirement for stabilizing the direct-current bus voltage is met, and constant-current quick charging of the electric automobile is achieved; the system comprises an acquisition module, a determination module, a front-stage control module and a rear-stage control module which are connected with an off-board charger system of the electric vehicle.

Description

technical field [0001] The invention belongs to the field of power electronics application technology, and in particular relates to a fast charging control method and system for an electric vehicle based on a virtual synchronous motor. Background technique [0002] The exponential growth of traditional fuel vehicles has led to a global energy crisis and increasingly serious environmental pollution problems. Vigorously developing electric vehicles has become an important measure to address climate change and promote energy conservation and emission reduction. The rapid growth of the number of electric vehicles has made the proportion of this new type of active load in the distribution network increasing day by day. It is of great significance to the safe and stable operation of the power grid. [0003] Electric vehicle charging methods are divided into slow charging and fast charging according to the charging power. The charging current of slow charging is small, and the ch...

AI Technical Summary

Problems solved by technology

However, this solution uses resistors to simulate the rechargeable battery of electric vehicles, and realizes constant voltage charging through double closed-loop control. The charging mode is not clear, and fast charging usually uses constant current or constant power charging; secondly, due to the use of an ideal power grid, the simulation results cannot prove the power of VSM. Primary FM Characteristics

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