CN105048612A - Electric vehicle bidirectional transmission intelligent charging pile - Google Patents

Abstract

The invention discloses an intelligent charging pile system which is used for interconnecting an electric vehicle and a power grid and capable of transmitting power in a bidirectional way. The charging pile system comprises an information extracting module, a detecting module, a calculating module, a bidirectional transmission module and a rapid charging module. The charging pile and a charging method thereof can achieve bidirectional power transmission between the electric vehicle and the power grid. By using the high-capacity energy storage equipment of the electric vehicle, the charging pile can make the power grid frequency fluctuation adjusted. An alternative scheme is provided for the stability of the intelligent power grid.

Description

A kind of bidirectional electric automobile transmission Intelligent charging spot

Technical field

The present invention relates to a kind of bidirectional electric automobile transmission Intelligent charging spot, belong to technical field of electric power.

Background technology

Along with the commercialization of electric automobile, the impact that electric automobile is connected with electrical network between V2G (vehicletogrid) also receives publicity.The Large Copacity energy storage device that electric automobile is equipped with can well become the distributed energy storage equipment of electrical network.Be connected with electrical network by electric automobile, solve the problem of the mains frequency skew that distributed energy power fluctuation causes.Electric automobile is adopted and presets intelligent charge control, the electric automobile being in idle state is combined, by charging pile, two-way power delivery is carried out to electrical network, with this, mains frequency skew is suppressed.

Electric automobile charging pile is that one is fixedly mounted on outside electric automobile, is connected with electrical network, for the vehicle-mounted charger of electric automobile provides the electric supply installation of power supply.Tradition charging pile comprises: pile body, electrical module, protection module and metering module.Pile body comprises shell and human-computer interaction interface, and according to the difference of mounting means, pile body can be divided into console mode pile body and upper arm formula pile body two kinds.Electrical module comprises charging socket, service cable, power supply transfer terminal board etc.Metering module comprises electric energy meter, far management system, reader device etc.Traditional charging pile mainly carries out single charge function to electric automobile, and do not consider and carry out alternately with electrical network, this is also the important research direction of intelligent grid, therefore, the present inventor studies this, develops the Intelligent charging spot of the transmitted in both directions power for electric automobile and electrical network specially.

Summary of the invention

The object of the present invention is to provide the function of a kind of transmitted in both directions of charging pile, by information interaction and the control of multiple module, for electric automobile access electrical network is accomplished, the mains frequency fluctuation caused for access new forms of energy suppresses.

To achieve these goals, solution of the present invention is:

For electric automobile and Power System Interconnection and can the charging pile system of transmitted in both directions power, this charging pile system comprises information extraction modules, detection module, computing module, transmitted in both directions module, quick charge module.Described information extraction modules is received information from car owner, be connected with computing module, described detection module is connected with electric automobile by power transmission line, Detection Information is connected with quick charge module with computing module, transmitted in both directions module, described computing module is according to the data of information extraction modules and detection module, be connected with quick charge module with transmitted in both directions module respectively, transmitted in both directions module is connected with quick charge module with calculating respectively.

Described information extraction modules, needs to obtain from car owner or user side the charging interval T that presets, and when leaving the required charging electric vehicle state SOC1 reached.According to two parameters extracted, be connected with described computing module.

Described detection module, according to the power transmission line that charging pile is connected with electric automobile, detects the SOC state SOC2 of battery pack in electric automobile, and is connected with electrical network, the difference f of detection of grid ongoing frequency and rated frequency.According to two parameters extracted, be connected with described computing module.

Described computing module, be connected with detection module with described information extraction modules, according to the parameter T of described information extraction modules transmission and the parameter SOC2 of SOC1 and the transmission of described detection module, under calculating quick charge mode, battery pack charges to the time T1 of required SOC1 from SOC2 state, calculate T2=T-T1 standby time of electric automobile, whether determination time T2 is greater than 30 minutes.

Described computing module, at determination time T2 when being greater than 30 minutes, is connected with described transmitted in both directions module.

Described transmitted in both directions module, is connected with detection module with described computing module, according to the signal T2 of described computing module transmission, and SOC2 and f of described detection module transmission, to be connected to take droop control to the battery pack of electric automobile with electrical network.Described droop control is on the basis of Tracking Frequency of Power Grids skew f, control described charging pile and charge and discharge control is carried out to batteries of electric automobile group, when mains frequency skew f>0, charging electric vehicle, when mains frequency skew f<0, batteries of electric automobile group is discharged.Described battery pack SOC balance controls, and is to described battery pack SOC monitoring state, ensures in charge and discharge process, and battery pack there will not be the phenomenon overcharging or excessively put.

Described quick charge module, be connected with detection module with described computing module, transmitted in both directions module respectively, when described computing module judges T2<0 standby time, enter quick charge module, after described transmitted in both directions module terminates T2 standby time, enter quick charge module, described detection module provides batteries of electric automobile group current SOC state SOC2 to described quick charge module.Described quick charge module mainly carries out the quick charge of big current to batteries of electric automobile group, be only to carry out charging and no longer drop into electrical network carry out frequency modulation from maximum different of described transmitted in both directions module charging modes.

Accompanying drawing explanation

Fig. 1 is the bidirectional electric automobile transmission charging pile module diagram of the present embodiment.

In figure: 1-information extraction modules, 2-detection module, 3-computing module, 4-transmitted in both directions module, 5-quick charge module.

Embodiment

Below in conjunction with accompanying drawing, the invention will be further described.

As shown in Figure 1, a kind of bidirectional electric automobile transmission charging pile provided by the invention, comprise information extraction modules, detection module, computing module, transmitted in both directions module, quick charge module, described information extraction modules is received information from car owner, be connected with computing module, described detection module is connected with electric automobile by power transmission line, Detection Information and computing module, transmitted in both directions module is connected with quick charge module, described computing module is according to the data of information extraction modules and detection module, be connected with quick charge module with transmitted in both directions module respectively, transmitted in both directions module is connected with quick charge module with calculating respectively.Whole charging process brings into use charging pile and inputting predetermined information, to car owner or user drive to leave charging pile from car owner or user.

The unbalanced supply-demand of electrical network can be obtained by the frequency shift (FS) f detecting the socket that described charging pile be connected with electrical network, and therefore electric automobile is connected with electrical network the power P produced _v2Gcan control according to the droop characteristic of frequency shift (FS) f, can obtain:

$P_{V2G}=\left\{\begin{array}{cc}{K}_{V2G}f& \left(\right|K_{V2G}f|\&le;P_{\max })\\ P_{\max }& (P_{\max }<|K_{V2G}f\left|\right)\end{array}\right.$

The wherein batteries of electric automobile group maximum power P that can export and receive _maxbe subject to the characteristic restriction of charging pile, electric automobile and electrical network coefficient of association K _v2Gdetermined by the fluctuation range of balance load FREQUENCY CONTROL LFC (loadfrequencycontrol) and battery pack SOC.When battery pack SOC is close to full value, high-power charging be limited, in the electric automobile of long period is connected with electrical network, considers the non-vanishing and described batteries of electric automobile group loss of described frequency shift (FS) f, suppose that battery pack SOC can estimate to obtain accurately:

$K_{V2G}=K_{\max }\{1-{\left(\frac{\mathrm{SOC}-{\mathrm{SOC}}_{\mathrm{low}\left(\mathrm{high}\right)}}{{\mathrm{SOC}}_{\max \left(\min \right)}-\mathrm{SO}{C}_{\mathrm{low}\left(\mathrm{high}\right)}}\right)}^n\}$

Wherein K _maxfor maximum electric automobile and electrical network coefficient of association, SOC _min, SOC _low, SOC _high, SOC _maxbeing respectively described batteries of electric automobile group SOC state is minimum (10%), lower value (20%), and high value (80%), peak (90%), n represents battery pack SOC state and remains on 50%.

In order to meet charging interval T and SOC1 that described car owner and user preset, if the predetermined charging interval is shorter, then adopts quick charge mode, charge with maximum discharge power.When preset charged ample time, then droop control is adopted to reduce frequency shift (FS).Represent by following formula:

$P_{\mathrm{SC}}=\left\{\begin{array}{cc}\frac{K_{\max }}{2}f+\frac{P_{\max }}{2}& \left(\right|K_{\max }f|\&le;P_{\max })\\ P_{\max }& (P_{\max }<K_{\max }f)\\ 0& (K_{\max }f<P_{\max })\\ -P_{\max }& (f<{\mathrm{\&Delta;f}}_{\min })\end{array}\right.$

Wherein P _sCfor the charge power of battery pack.

Claims (6)

1. a bidirectional electric automobile transmission Intelligent charging spot, it is characterized in that: comprise information extraction modules, detection module, computing module, transmitted in both directions module, quick charge module, described information extraction modules is received information from car owner, be connected with computing module, described detection module is connected with electric automobile by power transmission line, Detection Information and computing module, transmitted in both directions module is connected with quick charge module, described computing module is according to the data of information extraction modules and detection module, be connected with quick charge module with transmitted in both directions module respectively, transmitted in both directions module is connected with quick charge module with calculating respectively.

2. information extraction modules as claimed in claim 1, is characterized in that extracting the charging interval of car owner's input and the charged state requiring to reach, and by information transmission to described computing module.

3. detection module as claimed in claim 2, is characterized in that detection batteries of electric automobile group SOC state and mains frequency offset f, and Detection Information is transferred to described computing module, transmitted in both directions module, quick charge module.

4. computing module as claimed in claim 3, it is characterized in that the information transmitted according to described information extraction modules and detection module judge electric automobile be access described in transmitted in both directions module, or the quick charge module described in accessing.

5. transmitted in both directions module as claimed in claim 4, is characterized in that the SOC value that provides according to described detection module and mains frequency deviant f, and being connected with electrical network to electric automobile adopts droop control, balances control to batteries of electric automobile group employing SOC.

6. quick charge module as claimed in claim 4, is characterized in that the SOC value provided according to described detection module, electric automobile is taked to the charging modes of maximum power.