Electric automobile battery changing device and charge management method thereof

Abstract

The invention provides an electric automobile battery changing device and a charge management method thereof. The device and method are used for battery charging and changing for an electric automobile and provides a V2G function for a power grid automatically for maintaining voltage stabilization of the power grid. The electric automobile battery changing device includes a battery charge-discharge device and an electric automobile battery units connected in specific manners and in different SOCs, and a signal collecting system collecting states of the power grid in the local area and other positions. According to the invention, service needs of the battery changing device are estimated and the charge-discharge device is controlled. Besides, the states of the power grid are monitored on the basis of satisfying battery changing requirements. Composite variables including active power and passive power are used for maintaining voltage stability of the power grid and enabling the power grid voltage to be within a stability range.

Description

Technical field [0001] The invention relates to an electric vehicle battery exchange device and a charging management method thereof. More specifically, it relates to an electric vehicle battery exchange device with V2G function and a charging management method thereof. Background technique [0002] As human beings pay more attention to environmental protection, electric vehicles are becoming more and more popular as a new type of transportation with close to zero emissions. During the driving process of electric vehicles, the limited energy stored in the power battery is consumed, so the battery needs Regular charging, in most cases, the charging power is borne by the grid. [0003] The power system has high requirements for frequency and voltage stability. This stability is achieved by the matching of generation capacity and load capacity. Due to the uncontrollability of the load, the stability of the power system is determined by the power grid dispatching center. On the basis...

AI Technical Summary

Problems solved by technology

[0011] The disadvantage of Patent Document 1 is that real-time monitoring of each electric vehicle requires a relatively complete wireless network. Due to the driver's uncontrollability, it is difficult to carry out the V2G functions of multiple electric vehicles at the same time. Rarely will actively provide V2G functions to the grid

At the same time, although the status of electric vehicles can be monitored in real time, their charging load is still uncontrolled, which will still affect the stability of the power grid.

[0012] The disadvantage of patent document 2 is that the system can only manage and dispatch hybrid electric vehicles, but cannot manage pure electric vehicles. At the same time, similar to patent document 1, real-time monitoring of each hybrid electric vehicle requires a relatively complete wireless network

At the same time, in this system, the V2G reactive power comes from the chemical energy of the vehicle fuel, which is an uneconomical method

[0013] The disadvantage of Patent Document 3 and Patent Document 4 is that these devices cannot balance the contradiction between the power exchange demand of electric vehicles and the V2G function of the grid

For example, the device in Patent Document 3 can only realize the V2G function by using the electric energy during the discharge maintenance process of the empty battery, and the battery discharge and normal battery charging are realized by different hardware devices, which is difficult to provide stable V2G functions. At the same time, the hardware structure is more complicated and the cost is higher

In the device invented in Patent Document 4, each battery requires a separate charging and discharging device to charge, so the hardware cost is very high, and the device can only provide V2G functions when the power grid fails, and the adaptability is narrow

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