KR101549551B1 - Driving apparatus for electric vehicle - Google Patents

Abstract

The embodiment of the present invention provides a driving apparatus for an electric vehicle which includes a first battery which supplies first DC power which is charged; a second battery which supplies second DC power which is charged; first to third field coils which are included in a motor and are Y-connected based on a common contact point, a switching unit which is connected between the common contact point and the first battery and performs a switching operation to charge either the first battery or the second battery, an inverter unit which converts the second DC power into first to third AC power with different phases and supplies the first to third AC power to the first to third field coils in a motor driving mode, or supplies a current stored in at least one from the first to third field coils to charge either the first battery or the second battery in a charging mode, and a control unit which controls the switching unit and the inverter unit.

Description

≪ Desc / Clms Page number 1 > Driving apparatus for electric vehicle &

An embodiment relates to an electric vehicle drive apparatus.

In recent years, demand for environmentally friendly electric vehicles (EVs) has been increasing due to the strengthening of global environmental regulations and energy cost reduction. In the case of the US and Europe, In Korea, interest and research on green cars have been actively pursued as part of low carbon green growth.

On the other hand, an electric vehicle is equipped with a battery for operating a driving motor and various electric devices for driving a car, and an air conditioner for summer cooling or winter heating.

The electric vehicle is usually provided with an ISG (Integrated Starter Generator) for starting the engine and rotating the drive motor. The ISG operates in a motoring mode for rotating the motor and a power generation mode for generating a predetermined output voltage.

Also, the electric vehicle may be provided with a plurality of batteries having different charging voltages. At this time, each battery can be charged through the power generation mode of the ISG.

Since the ISG is usually configured to generate a high output voltage, it can be charged through the output voltage of the ISG in the case of a high voltage battery. However, in the case of a low voltage battery, charging is not possible through the output voltage of the ISG, Converter is required.

That is, the DC-DC converter functions to lower the high output voltage of the ISG to the charging voltage of the low voltage battery.

However, the DC-DC converter is heavy in weight and bulky to increase the weight of the electric automobile, lower the internal space utilization, and further reduce the efficiency of the electric vehicle.

Therefore, even when a plurality of batteries having different charging voltages are provided, a structure capable of charging each battery through a single ISG without a separate DC-DC converter is required.

In order to charge the high voltage battery and the low voltage battery using the ISG, the rotational force of the engine must be transmitted to the ISG, and it is difficult to charge the high voltage battery and the low voltage battery using the ISG when the engine is not driven.

Therefore, a structure for emergency charging of a low-voltage battery is required even in a state in which the engine is not driven.

An object of the present invention is to provide an electric vehicle drive apparatus capable of charging any one of a high voltage battery and a low voltage battery with another battery in a state where the engine of the automobile is stopped.

The electric vehicle driving apparatus according to the embodiment includes a first battery for supplying a charged first dc power source, a second battery for supplying a charged second dc power source, and a motor connected to the Y- 1 to 3, the common contact, and the first battery, and switches to charge any one of the first and second batteries. In the motor drive mode, the second dc power is supplied to the phase Of the first to third field coils so that either one of the first and second field coils is charged in the charging mode or the first to third field coils are supplied to the first to third field coils, An inverter unit for supplying a current stored in one of the inverter units, and a controller for controlling the switching unit and the inverter unit.

The electric vehicle driving apparatus according to the embodiment can form a single module by using a switch unit, an inverter unit, and a field coil so as to charge a high voltage battery and a low voltage battery without using a separate converter, Thereby, there is an advantage that space utilization can be increased.

1 is a control block diagram showing a configuration of an electric vehicle drive system according to an embodiment.
2 is a circuit diagram showing an electric vehicle drive system according to an embodiment.
3 is a timing chart showing a control signal when the electric vehicle driving apparatus according to the embodiment operates in the motor driving mode.
4 is a diagram illustrating an example of a current path according to the control signal shown in FIG.
5 is a timing chart showing an example of a control signal in a buck mode operation of a charge mode of the fms electric vehicle drive apparatus according to an embodiment.
6 is a diagram showing a current path according to the control signal shown in Fig.
FIG. 7 is a timing chart showing an example of a control signal during a boost mode operation of a charge mode of an electric vehicle drive system according to an embodiment.
8 is a diagram showing a current path according to the control signal shown in Fig.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an electric vehicle driving apparatus (hereinafter also referred to as a driving apparatus) according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In addition, the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted. For convenience of explanation, the size and shape of each constituent member shown may be exaggerated or reduced have.

On the other hand, terms including an ordinal number such as a first or a second may be used to describe various elements, but the constituent elements are not limited by the terms, and the terms may refer to a constituent element from another constituent element It is used only for the purpose of discrimination.

1 is a control block diagram showing a configuration of an electric vehicle drive system according to an embodiment.

Referring to FIG. 1, an electric vehicle driving apparatus may include first and second batteries 110 and 120 and a motor driving unit 200.

Here, the first and second batteries 110 and 120 can charge or discharge the first and second dc power sources Vdc1 and Vdc2, which are different from each other.

In an embodiment, the first dc power source Vdc1 of the first battery 110 may be 12V and the second dc power source Vdc2 of the second battery 120 may be 48V, but is not limited thereto.

The second battery 120 supplies the second dc power source Vdc2 to a stator coil (hereinafter referred to as a field coil) which is wound around the stator of the motor M by Y wiring , Or the second dc power source (Vdc2) can be charged with a power source output from a common contact (not shown) of the field coil.

Also, the first battery 110 supplies power to an electronic device included in the automobile, for example, an engine starting device, an electronic device, and the like. The first dc power source (Vdc1) is connected to the power output from the common contact of the field coil It can be charged.

The motor driving unit 200 may include a driving unit 210 and a control unit 250.

Here, the driving unit 210 may include a switch unit 220, a motor M, and an inverter unit 230.

That is, the switch unit 220 supplies the first dc power source Vdc1 charged in the first battery 110 to the motor M in accordance with the switch turn-on or turn-off operation, The first dc power source Vdc1 can be charged.

The switch unit 220 may include a switching element such as a field effect transistor (FET), a BJT, and a relay, and a detailed description thereof will be given in FIG.

As described above, the motor M may include a stator and a rotor in which the field coil is wound, and one side of the switch unit 220 may be connected to a common contact of the field coil.

The inverter unit 230 may generate a three-phase ac power source as the second dc power source Vdc2 supplied from the second battery 220 and supply the three-phase ac power to the field coil.

The inverter 230 supplies the three-phase AC power to the motor M under the control of the controller 250 or the first and second batteries 110 and 120 to the power source Charging can be done.

The control unit 250 may control the switch turn-on and turn-off operations of the switch unit 220 and the inverter unit 230, respectively.

That is, the control unit 250 operates the switch unit 220 in a switch turn-off state in the motor drive mode operation in which the motor M is driven, operates the inverter unit 230 in the switch turn- (Vac1, Vac2, Vac3) can be controlled to be supplied.

If the power levels of the first and second dc power sources Vdc1 and Vdc2 charged in the first and second batteries 110 and 120 are lower than the set reference power level, And may operate in a charging mode in which any one of the batteries 110 and 120 is charged.

At this time, when the first battery 110 is charged in the charging mode, the control unit 250 operates the field coil of the motor M and the inverter unit 230 as a buck converter, The switch unit 220 and the inverter unit 230 are operated by the turn-on and turn-off operations of the switch unit 220 and the inverter unit 230 so that the field coil and the inverter unit 230 of the motor M are operated as the boost converter, Can be controlled.

2 is a circuit diagram showing an electric vehicle drive system according to an embodiment.

Referring to FIG. 2, the electric vehicle drive apparatus may include first and second batteries 110 and 120 and a motor driver 200 as described above with reference to FIG.

When the first battery 110 operates in the charging mode for the second battery 120, the first battery 110 may output the charged first dc power source Vdc1.

The second battery 120 may operate in the charging mode for the first battery 110 or may output the charged second dc power source Vdc2 when operating in the motor driving mode.

The motor driving unit 200 may include a switch unit 220, a motor M, an inverter unit 230, and a control unit 250, and the control unit 250 is not shown in FIG.

The switch unit 220 is connected to the first and second switch elements 220 and 220 connected between the first battery 110 and the common contact points (cm) of the first to third field coils La, Lb and Lc included in the motor M. [ Q1, Q2).

In the embodiment, the switch portion 220 is shown and described as including two first and second switch elements Q1 and Q2, but may include only one switch element, but is not limited thereto.

Here, the first and second switching elements Q1 and Q2 are described as being a field-effect transistor (FET), but the present invention is not limited thereto.

A forward diode may be connected to the drain and source terminals of the first switch element Q1 and a reverse diode may be connected to the drain and source terminals of the second switch element Q2.

Here, the forward diode and the reverse diode may be used to remove a parasitic capacitance component in the device when at least one of the first and second switching devices Q1 and Q2 is turned on and off, I do not.

In the embodiment, the first and second switching elements Q1 and Q2 are described as being switched on and off in the same manner by the controller 250 described above with reference to FIG.

The first and second switching elements Q1 and Q2 are turned on when the control unit 250 operates in the charging mode for the first and second batteries 110 and 120. When the first and second switching elements Q1 and Q2 are operated in the motor driving mode, Off operation, but is not limited thereto.

The motor M may include first to third field coils La, Lb and Lc Y-connected to a common contact point (cm) as described above.

At this time, the inductance values of the first to third field coils La, Lb, and Lc may vary depending on the winding width and thickness, and are charged by the first to third ac power sources Vac1, Vac2, The first to third current values may be varied, but the present invention is not limited thereto.

The inverter unit 230 includes a first inverter ISa connected in parallel with the first field coil La at a first contact point a, a second field coil Lb connected in parallel with the second field coil Lb at a second contact point b, And a third inverter ISc connected in parallel at the third contact c with the second inverter ISb and the third field coil Lc.

The first inverter ISa includes a first damping switch element Sa and a second damping element Dm for supplying a first ac power source Vac1 in pulse form to the first field coil La through a first contact a, (S'a).

The second inverter ISb is connected to the second slave arm switch element Sb and the second lower arm switch element Sb for supplying the second ac power source Vac2 in pulse form to the second field coil Lb through the second contact b, (S'b).

The third inverter ISc includes a third dummy arm switching element Sc for supplying a third ac power source Vac3 in pulse form to the third field coil Lc through a third contact c, And a switch element S'c.

The first embedded third inverters ISa to ISc are connected in parallel to each other and receive the second dc power source Vdc2 from the second battery 120 to generate the first to third ac power sources Vac1 to Vac3 .

FIG. 3 is a timing chart showing a control signal when the electric vehicle driving apparatus according to the embodiment operates in the motor driving mode, and FIG. 4 is a diagram illustrating an example of a current path according to the control signal shown in FIG.

3, the controller 250 of the electric vehicle driving apparatus outputs a switch turn-on signal (On) and a turn-off signal (Off) to the switch unit 220 and the inverter unit 230 in an arbitrary section (p) do.

3 shows an example of a control signal supplied from the control unit 250 to the switch unit 220 and the inverter unit 230 when the motor operates in the motor drive mode, but the present invention is not limited thereto.

First, the first and second switching elements Q1 and Q2 operate as a switch turn-off in an arbitrary section p.

As shown in Fig. 3, the first sway arc switch element Sa switches on the first section p1 of the arbitrary section p and the switches turn-off operation of the second and third sections p2 and p3 do.

The second sway arc switch element Sb is switched on at the second section p2 of the arbitrary section p and switches off at the first and third sections p1 and p3.

The third sway arc switch element Sc is switched on in the third section p3 of the arbitrary section p and switches on and off in the first and second sections p1 and p2.

The first lower arm switch element S'a switches on from the set period of the second period p2 to the set period of the third period p3 and the first lower arm switch element S'a is turned on during the first period p1, The switch turn-off operation is performed on the second and third sections p2 and p3.

The second lower arm switch element S'b switches on from the previous section of the first section p1 to the set section of the first section p1 and the set section of the third section p3, The switch turns off the first to third sections p1, p2 and p3.

The third lower arm switch element S'c is switched on during the setting period of the first section p1 and the second section p2 and is turned on during the other first through third sections p1, Off operation.

Here, the current path shown in Fig. 4 is a current path for the second dc power source vdc2 supplied from the second battery 120 during the first one of the intervals p.

First, the control unit 250 controls the first and second switch elements Q1 and Q2, the first to third cantilever switch elements Sa, Sb and Sc and the control signal according to the first section p1 shown in FIG. To the first to third lower arm switch elements S'a, S'b, S'c.

At this time, the first current path (1) includes the first saggeway switch element Sa, the first contact point a, the first field coil La, the common contact point cm, the second field coil Lb, The contact b and the second lower arm switch element S'b.

Thereafter, the second current path (2) is connected to the first dummy switch element Sa, the first contact point a, the first field coil La, the common contact point cm, the third field coil Lc, The contact point c and the third lower arm switch element S'c.

In this way, the control unit 250 can form the first and second current paths (1, 2) in the first section p1 and can drive the motor M.

The timing diagram and the current path shown in Figs. 3 and 4 are described by way of example, and the timing for switch turn-on and turn-off can be controlled, but is not limited thereto.

FIG. 5 is a timing chart showing an example of a control signal during the buck mode operation of the charging mode of the fms electric vehicle driving apparatus according to the embodiment, and FIG. 6 is a diagram showing a current path according to the control signal shown in FIG.

5, the control unit 250 of the electric vehicle driving apparatus outputs a switch turn-on signal On and a turn-off signal Off to the switch unit 220 and the inverter unit 230 in an arbitrary section (p) do.

5 is a graph showing the relationship between the voltage of the first dc power source Vdc1 and the voltage of the first dc power source Vdc1 when the power level of the first dc power source Vdc1 is lower than the reference power level, 1 through third field coils La, Lb, and Lc represent control signals for operating as a buck converter, but are not limited thereto.

The controller 250 operates the first and second switch elements Q1 and Q2 in the first section b11 of the arbitrary section b1 in the switch turn off state.

At this time, the controller 250 switches on the first and second slave arm switch elements Sa and S'b during the first period b11.

Here, the controller 250 switches on the second lower arm switch element S'b to the second section b12 of the arbitrary section b1.

The control unit 250 switches the first and second switch elements Q1 and Q2 on the second and third sections b12 and b13 of the arbitrary section b1 to switch on the first and second switch elements Sa, Off operation.

The controller 250 turns off the second lower arm switch element S'b in the third period b13 and turns on the first sway arc switch element S'a.

Here, the current path shown in Fig. 6 will be described as follows.

First, in the first section b11, the second current source Vdc2 is supplied from the second battery 120 to the first current path (1).

That is, the first current path (1) includes the first dummy arm switch element Sa, the first field coil La, the second field coil Lb, and the second down arm switch element S'b as described above. A current path can be formed in the first section b11.

At this time, the first field coil La may be charged with the first field current I_La and the second field coil Lb may be charged with the second field current I_Lb.

That is, the first and second field coils La and Lb are current storage elements and can charge (store) the first and second field currents I_La and I_Lb according to the input power source.

Then, in the second section b12, the second current path (2) passes through the second down-arm switch element S'b, the second field coil Lb and the first and second switch elements Q1 and Q2. 1 current path can be formed by the battery 110. [

That is, the second current path (2) allows the second current I_Lb charged in the second field coil Lb to flow to the first battery 110 through the first and second switching elements Q1 and Q2, And the first dc power source Vdc1 corresponding to the current I_Lb is charged.

Thereafter, in the third section b13, the third current path (3) flows through the first down-arm switch element S'a, the first field coil La and the first and second switch elements Q1 and Q2. 1 current path can be formed by the battery 110. [

That is, the third current path (3) allows the first current I_La charged in the first field coil La to flow through the first and second switching elements Q1 and Q2 to the first battery 110, Is a current path in which the first dc power source Vdc1 corresponding to the current I_La is charged.

In the embodiment, the first and second field coils La and Lb have the same inductance value so that the same first and second currents I_La and I_Lb are charged, 1 and 2 currents I_La and I_Lb are sequentially supplied to the first battery 110.

If the sum current of the first and second currents I_La and I_Lb charged in the first and second field coils La and Lb corresponds to the first dc power source Vdc1, The first and second lower arm switch elements S'a and S'b are turned on so as to overlap with the two currents I_La and I_Lb.

FIG. 7 is a timing chart showing an example of a control signal in the boost mode operation of the charge mode of the electric vehicle drive system according to the embodiment, and FIG. 8 is a diagram showing a current path according to the control signal shown in FIG.

7, the control unit 250 of the electric vehicle driving apparatus outputs a switch turn-on signal On and a turn-off signal Off to the switch unit 220 and the inverter unit 230 in an arbitrary section b2, do.

7 is a graph showing the relationship between the power supply level of the second dc power source Vdc2 charged in the second battery 120 and the voltage level of the second dc power source Vdc2, 1 through third field coils La, Lb, and Lc represent control signals for operating as the boost converter, but the present invention is not limited thereto.

The controller 250 operates the first and second switch elements Q1 and Q2 in the first and second sections b21 and b22 of the arbitrary section b2 by switch on.

At this time, the controller 250 turns on the first lower arm switch element S'a during the first section b21, and during the second and third sections b22 and b23 of the arbitrary section b2, And the low-arm switch element S'b is switched on.

The controller 250 switches the first and second switch elements Q1 and Q2 to the third section b23 of the arbitrary section b1 and turns on the first slave arm switch element Sa .

Here, the current path shown in Fig. 8 will be described as follows.

First, in the first section b21, the first dc power source Vdc1 is supplied from the first battery 110 to the first current path (1).

That is, as described above, the first current path (1) includes the first and second switching elements Q1 and Q2, the first field coil La, and the current path passing through the first lower arm switch element S'a. 1 section b21.

In the second section b22, the second current path (2) has a current passing through the first and second switching elements Q1 and Q2, the second field coil Lb and the second lower arm switch element S'b A path can be formed.

At this time, the first field coil La may be charged with the first field current I_La and the second field coil Lb may be charged with the second field current I_Lb.

That is, the first and second field coils La and Lb are current storage elements and can charge (store) the first and second field currents I_La and I_Lb according to the input power source.

Thereafter, in the third section b13, the third current path (3) flows through the second down-arm switch element S'b, the first and second field coils La and Lb, and the first s- A current path can be formed in the second battery 120. [

The third dc power source Vdc2 corresponding to the sum current of the first and second currents I_La and I_Lb stored in the first and second field coils La and Lb is connected to the second battery 120 ). ≪ / RTI >

In the embodiment, the first and second field coils La and Lb have the same inductance value so that the same first and second currents I_La and I_Lb are charged, And the sum current of the first and second currents I_La and I_Lb is supplied to the second battery 120.

If the sum current of the currents charged in the first, second and third field coils La, Lb and Lc corresponds to the second dc power source Vdc2, the first, The inverter 230 can be controlled so that the sum current of the currents charged in the coils La, Lb and Lc is supplied to the second battery 120. However, the present invention is not limited thereto.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

Claims (10)

A first battery for supplying a charged first dc power source;
A second battery for supplying a charged second dc power source;
First to third field coils included in the motor and Y-connected with respect to the common contact;
A switching unit connected between the common contact and the first battery, the switching unit switching to charge any one of the first and second batteries; And
In the motor drive mode, the second dc power source is converted into first to third ac power sources having different phases and supplied to the first to third field coils. In the charge mode, either one of the first and second batteries An inverter unit for supplying a current stored in at least one of the first to third field coils to be charged; And
And a control unit for controlling the switching unit and the inverter unit. The method according to claim 1,
Wherein,
Wherein when the power level of each of the first and second dc power sources supplied from the first and second batteries is lower than a reference power level, the switching unit and the inverter unit are switched to the charging mode so that any one of the first and second batteries is charged. An electric vehicle drive device for controlling the vehicle. The method according to claim 1,
Wherein,
Wherein at least one of the first to third field coils, the switching unit and the inverter unit are controlled to operate as a buck converter when the first battery is charged in the charging mode,
Wherein at least one of the first to third field coils, the switching unit, and the inverter unit are operated as the boost converter when the second battery is charged in the charging mode. The method according to claim 1,
The switching unit includes:
And at least one switch element connected between the first battery and the common contact. 5. The method of claim 4,
Wherein the at least one switch element comprises:
An electric vehicle drive device which is a field effect transistor. 5. The method of claim 4,
The switch element includes:
Wherein in the charging mode, after the switch is turned off during charging of the first battery, the electric current stored in at least one of the first to third field coils is switched on to be supplied to the first battery. 5. The method of claim 4,
The switch element includes:
Wherein in the charging mode, a switch is turned on when charging the second battery to store a current in at least one of the first to third field coils, and then, the current stored in at least one of the first to third field coils And the switch is turned off so as to be supplied to the second battery. The method according to claim 1,
The inverter unit includes:
A first damping switch element and a first damping switch element supplying the first ac power to the first field coil and connected in parallel with the first field coil;
A second sag rock switch element and a second down arm switch element supplying the second ac power to the second field coil and connected in parallel with the second field coil; And
And a third damping switch element and a third damping switch element supplying the third ac power to the third field coil and connected in parallel with the third field coil. 9. The method of claim 8,
The inverter unit includes:
When the first battery is charged in the charging mode, the second dc power source is supplied to at least two of the first to third field coils during a switch turn-off operation of the switching unit Wherein at least one of the first to third cantilever switch elements is switched on when at least one of the first to third cantilever switch elements is turned on and at least one of the first to third cantilever switch elements is turned on when the switch is turned on, . 9. The method of claim 8,
The inverter unit includes:
At least two of the first to third down-arm switch elements are supplied with at least two of the first to third field coils during the switch turn-on operation of the switching unit when the second battery is charged in the charging mode, Wherein at least one of the first to third cantilever switch elements is switched on during the switch turn-off operation of the switching unit and the first to third lower-arm switch elements are switched off, Driving device.

Images