KR20200038152A - An integrated multi battery charging system having an active power decoupling capability for an electric vehicle - Google Patents

Abstract

The present invention is provided between a first circuit part, a DC link connected to the other end of the first circuit part, the DC link and the first battery, the power supply being connected to one end, the function of converting an AC voltage into a DC voltage, A second circuit part for charging or discharging the first battery, a third circuit part provided between the DC link and the second battery, and the first to third circuit parts charging or discharging the first battery according to an operation mode signal or , It is an invention for an integrated multi-charging system having an active power decoupling function for an electric vehicle, characterized in that the second battery is charged.
In the high voltage main battery charging mode, a part of the auxiliary battery charging circuit operates as an active filter to exclude a large-capacity filter capacitor, and the high voltage main battery charging function circuit and the auxiliary battery charging function circuit share a transformer, resulting in large size and material cost. It has the effect of reducing the number of expensive transformers.

Description

All-in-one multi charging system with active power decoupling for electric vehicles {AN INTEGRATED MULTI BATTERY CHARGING SYSTEM HAVING AN ACTIVE POWER DECOUPLING CAPABILITY FOR AN ELECTRIC VEHICLE}

The present invention relates to an integrated on-board charging system that combines a high voltage main battery charger having a vehicle to grid (V2G) function and a charger for charging an auxiliary battery in an electric vehicle. More specifically, in the high voltage main battery charging mode, a part of the auxiliary battery charging circuit can act as an active filter to exclude a large-capacity filter capacitor, and the high voltage main battery charging function circuit and the auxiliary battery charging function circuit share a transformer size. It relates to an on-board charging system for a compact type electric vehicle that can reduce the number of transformers having a large and expensive material.

Two batteries are used in a pure electric vehicle or a plug-in hybrid vehicle (hereinafter referred to as “electric vehicle”) in which a battery is charged from a system power source through a charger mounted on a vehicle. One is a high voltage main battery for traction motor drives, and the other is a secondary battery for auxiliary power supplies that power loads such as lighting and signal circuits, convenience functions, automatic seats and other electronic devices. Instead of the alternator in an existing internal combustion engine vehicle, this secondary battery is charged from the high-voltage main battery through a secondary battery charger. Vehicle battery chargers generally require a long life cycle, small volume and light weight.

The single-phase high-voltage main battery charger has its own power ripple factor that fluctuates twice the grid frequency, causing ripple on the DC link voltage. In order to smooth this low-frequency power ripple, a large-capacity capacitor is required, which is an important obstacle in reducing the size of the charger.

On the other hand, when charging the high voltage main battery with grid power or supplying power to the grid with high voltage main battery, insulate between the grid power and the high voltage main battery through a transformer for electrical safety and user safety. In addition, in order to prevent electric shock of a user even inside an electric vehicle, both the positive and negative poles of the high voltage main battery must be insulated from the vehicle chassis compared to the auxiliary battery connected to the vehicle chassis and the negative terminal. Therefore, a transformer is included in each of the high voltage main battery charger and the auxiliary battery charger, and the transformer is large and the component cost is relatively high due to the core material cost, so it is also a obstacle to lower the price of the electric vehicle charging system, reduce the size, and reduce the weight.

In the past, in order to solve some of the above problems, techniques for partially improving the snubber circuit or changing the switching frequency have been proposed, but the result is not limited enough, so the volume, weight, and price of the electric vehicle charging system are still reduced. Difficult to lower.

The present invention is to solve the problems as described above, charge a high-voltage main battery through bi-directional power transfer between an external power source and a high-voltage main battery with a single charging system or a high-voltage main battery with a V2G (Vehicle to Grid) function. The purpose is to supply power to the system.

In addition, it aims to charge the secondary battery in addition to the high voltage main battery charging function as described above with one charging system.

In addition, in the auxiliary battery charging mode, a part of the circuit that performs power transmission to the auxiliary battery is intended to exclude the use of a large-capacity filter capacitor by operating as a multi-purpose active power decompiling filter in the high voltage main battery charging mode.

In addition, the purpose of one charging system is to charge both batteries with only one transformer by performing the high voltage main battery charging function and the auxiliary battery charging function.

Also, by using a large-capacity filter capacitor or using only one transformer, the object is to significantly reduce the size, weight, and material cost of the charging system.

In addition, it is an object of the present invention to improve the reliability of the charging system because the number of parts can be reduced as described above.

The present invention is provided between a first circuit part, a DC link connected to the other end of the first circuit part, the DC link and the first battery, the power supply being connected to one end, the function of converting an AC voltage into a DC voltage, A second circuit portion for charging or discharging the first battery, a third circuit portion provided between the DC link and the second battery, and the first to third circuit portions charging or discharging the first battery according to an operation mode signal, 2 provides a charging system for an electric vehicle, characterized in that the battery is charged or discharged.

When the driving mode signal is in the first mode, the first circuit part and the second circuit part transfer energy from the power source to the first battery, or transfer energy from the first battery to the power source, and the third circuit part includes the It is preferable that an AC current flows from the DC link or to the DC link so that an AC voltage component by the power source does not appear on the DC link.

When the driving mode signal is the second mode, it is preferable that the second circuit part and the third circuit part transfer energy from the first battery to the second battery.

Preferably, the third circuit unit includes at least one mode switching switch that switches circuit connections according to the driving mode signal.

The third circuit portion includes a first semiconductor switch and a second semiconductor switch connected in series to both ends of the DC link, a first capacitor and a second capacitor connected in series to both ends of the DC link, and a negative terminal and a cathode of the DC link. A connected third capacitor, an inductor having one end connected to a node to which the first semiconductor switch and the second semiconductor switch are connected, and a mode switching switch connected to the other end and one end of the inductor, wherein the third capacitor includes a second power supply. It is preferred to be connected in parallel with.

When the operation mode signal is in the first mode, it is preferable that the other end of the mode switch is connected to a node to which the negative terminal of the first capacitor and the positive terminal of the second capacitor are connected.

The first circuit part and the second circuit part transfer energy in a unidirectional or bidirectional manner between the power source and the first battery, and a controller controls the first semiconductor switch of the third circuit part to remove an AC component of the DC link voltage. It is preferable to control the and the second semiconductor switch.

The controller inputs a DC link voltage error that is a difference between a DC link voltage command value (Vdc *) and a DC link voltage (Vdc), and outputs the third voltage controller 350 and the third voltage controller 350. And a third current controller 360 generating control signals of the first and second semiconductor switches 311 and 312 of the third circuit unit 300, wherein the third voltage controller 350 includes the DC link voltage error. Based on the difference between the compensation target voltage generation unit 351 for generating a compensation target voltage Vr for removing the AC component of the DC link voltage, and a zero command value and the compensation target voltage Vr. And a controller 352 for calculating the current command value I_Lr * of the inductor 320, and the third current controller 360 includes the current command value I_Lr * and the measured value I_Lr of the inductor 320. The value of the controller 361 that uses the difference between the inputs and the output of the controller 361 divided by the DC link voltage. A PWM generator that outputs a control signal that controls ON / OFF of the first and second semiconductor switches 311 and 312 of the third circuit unit based on the output of the divider 362 and the divider 362 to calculate It is preferable to include (363).

The voltage generation unit 351 to be compensated includes a time delay unit 351a that receives the DC link voltage error as an input, an output signal of the DC link voltage error signal, and the time delay unit 351a as inputs, It includes a frequency converter 351b for calculating the voltage to be compensated (Vr), the time delay unit (351a), the frequency (f) of the power supply (2) twice the frequency (2f) based on 1 / The time (1 / (8f)) corresponding to 4 cycles is delayed, and the frequency converter 351b uses the DC link voltage error signal and the output signal of the time delay unit 351a as inputs, and the power supply ( To calculate the compensation target voltage (Vr) by frequency-converting the component of the DC link voltage error (Vdc_err) having a frequency twice the frequency (f) of 2) to the component having the frequency (f) of the power supply (2). desirable.

The frequency converter 351b. In the 1-1 mode in which energy is transferred from the power source 2 to the first battery 20, a voltage to be compensated Vr is generated using Equation 3, and from the first battery 20 to the power source 2 In the 1-2 mode for transferring energy, it is preferable to generate the voltage Vr to be compensated using Equation (4).

,[Equation 3]

,

. [Equation 4]

.

Here, ω is the angular frequency (2πf) of the power supply 2.

The controller 352 for calculating the current command value I_Lr * of the inductor 320 is an error obtained by subtracting the voltage to be compensated from the zero command value, and the current command value I_Lr of the inductor 320 *) Is a proportional resonance (PR, Proportional-Resonant) controller, the proportional resonance controller is the sum of the proportional controller and at least one resonance controller, and the resonance frequency of the resonance controller is the power (2) frequency It is preferred to include.

When the operation mode signal is the second mode, the other end of the mode changeover switch 330 is connected to the positive terminal of the third capacitor 343, and the second circuit unit 200 is the first battery 20 It is preferable to transfer energy from the DC link, and the third circuit unit 300 transfers energy from the DC link to the second battery 30. The controller controls the DC link voltage controller 230 that controls the semiconductor switch of the second circuit unit based on the DC link voltage control error, and charges the second battery that generates the charging current command Ilo * of the second battery 30. Based on the current command generator 370; and the second battery charging current command (Ilo *) that is the output of the second battery charging current command generator 370, the control signals S31 and S32 of the semiconductor switches of the third circuit unit are generated. It is preferable to further include a second battery charging current controller 380 to be generated.

In addition, the second mode is a constant voltage of the second battery 30 with the energy of the first battery 20 and the 2-1 mode of charging the second battery 30 with a constant current with the energy of the first battery 20 It may be characterized in that it comprises a 2-2 mode for charging.

The second battery charging current command generator 370 is charged to output a predetermined current value in the case of the 2-1 mode in which the second battery 30 is charged with the constant current by the energy of the first battery 20 In the case of the 2-2 mode in which the second battery 30 is charged with the constant voltage by the energy of the current command generator 371 and the first battery 20, the voltage command value (Vlo *) and the voltage measurement of the second battery 30 The voltage controller 372 includes a second battery 30 including a proportional integral controller having a difference in value Vlo as an input, and the charging current command generation unit 371 and a second battery according to a driving mode signal Mode. It is preferable to include a charging mode switching unit 373 for outputting one of the outputs of the voltage controller 372 to the battery current command (Ilo *).

According to the present invention as described above has the following effects.

(1) A single charging system can charge the high-voltage main battery through two-way power transfer between the external power supply and the high-voltage main battery, or supply the power of the high-voltage main battery to the system through the V2G (Vehicle to Grid) function. It has the effect of charging or using a secondary battery to supply power to the high-voltage main battery or system.

(2) In the secondary battery charging mode, the circuit that performs power transmission to the secondary battery is a high-voltage main battery charging mode, and a part of the circuit operates as a multi-purpose active power decompiling filter to exclude the use of large-capacity filter capacitors. There is.

(3) Since one charging system performs a high voltage main battery charging function and a secondary battery charging function, it is possible to charge both batteries with only one transformer.

(4) By using a large-capacity filter capacitor or using only one transformer, there is an effect of greatly reducing the size, weight, and material cost of the charging system.

(5) Since the number of parts can be reduced, there is an effect of improving the reliability of the charging system.

Features, advantages and technical and industrial significance of the exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals designate like elements.
1 shows an example of a charging system for a conventional electric vehicle (including a high voltage main battery charger and an auxiliary battery charger).
2 shows a configuration example of the proposed charging system for an electric vehicle.
3 illustrates the flow of power when the driving mode signal is the first mode in the proposed charging system for an electric vehicle.
4 shows the flow of electric power when the driving mode signal is the second mode in the proposed charging system for an electric vehicle.
5 illustrates a control block diagram of the proposed charging system for an electric vehicle when the driving mode signal is the first mode.
6 shows a control block diagram of the battery current command generator when the operation mode signal is the 1-1-1 mode, the 1-1-2 mode, or the 1-2 mode.
7 shows a control block diagram of the DC link voltage controller 230, the second battery charging current command generator and the second battery charging current controller when the operation mode signal is the second mode.
8 illustrates a control block diagram of the second battery charging current command generator when the operation mode signals are in the 2-1 mode and the 2-2 mode.

Objects, features and advantages of the present invention described above will become more apparent through the following examples with reference to the accompanying drawings.

The following specific structures or functional descriptions are merely exemplified for the purpose of explaining embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention may be implemented in various forms and described in the specification or application It should not be construed as being limited to the examples.

Embodiments according to the concept of the present invention can be applied to various changes and may have various forms, so specific embodiments will be illustrated in the drawings and described in detail in the present specification or application. However, it is not intended to limit the embodiments according to the concept of the present invention to a specific disclosure form, it should be understood to include all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

Terms such as first and / or second may be used to describe various components, but the components are not limited to the terms. The above terms are only for the purpose of distinguishing one component from other components, for example, without departing from the scope of rights according to the concept of the present invention, the first component may be referred to as the second component, and similar Thus, the second component may also be referred to as a first component.

When a component is referred to as being connected or connected to another component, it should be understood that other components may exist in the middle, although they may be directly connected to or connected to the other components. On the other hand, when it is mentioned that one component is directly connected to or connected to another component, it should be understood that no other component exists in the middle. Other expressions to describe the relationship between the components, such as between ∼ between and immediately between ∼ or adjacent to ∼ and directly adjacent to ～, should also be interpreted.

The terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. Terms such as include or have in this specification are intended to designate the existence of a feature, number, step, action, component, part, or combination thereof described, one or more other features or numbers, steps, actions, It should be understood that the presence or addition possibilities of components, parts or combinations thereof are not excluded in advance.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. Terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined herein. Does not.

Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings. The same reference numerals in each drawing denote the same members.

Hereinafter, "electric vehicle" includes all of a mobile body that can be driven by electric charging, such as a pure electric vehicle, a plug-in hybrid vehicle, an electric bicycle, and an electric auto fav.

[Embodiment 1]

As shown in FIG. 2, the charging system for an electric vehicle is connected to a power supply 2 and one end, and includes a first circuit unit 100 and a first circuit unit 100 including a function of converting an AC voltage into a DC voltage. DC link connected to the other end, provided between the DC link and the first battery 20, the second circuit unit 200 for charging or discharging the first battery 20, the DC link and the second battery 30 ), The third circuit unit 300, the first to third circuit units 100, 200, 300 according to the operation mode signal charge or discharge the first battery 20, or the second battery 30 ) May be characterized by charging or discharging.

The first battery may be a high voltage main battery in an electric vehicle. The second battery may be an auxiliary battery for auxiliary power in an electric vehicle. The power supply ( vs , 2) may be a single-phase AC power supply.

[Embodiment 2]

As illustrated in FIG. 3, when the driving mode signal is in the first mode, the first circuit unit 100 and the second circuit unit 200 are transferred from the power source 2 to the first battery 20 or , Transfers energy from the first battery 20 to the power source 2, and the third circuit unit 300 is from the DC link so that the AC voltage component of the power source 2 does not appear in the DC link or It may be characterized in that an AC current flows through the DC link.

In addition, the first mode may be characterized by including a 1-1 mode and a 1-2 mode. The 1-1 mode is a mode for transferring energy from the power source 2 to the first battery 20, and the 1-2 mode is a mode for transferring energy from the first battery 20 to the power source 2. have.

Also, the 1-1 mode may include a 1-1-1 mode and a 1-1-2 mode. The 1-1-1 mode is a mode for charging the first battery 20 with a constant current, and the 1-1-2 mode is a mode for charging the first battery 20 with a constant voltage.

[Embodiment 3]

As illustrated in FIG. 4, when the driving mode signal is in the second mode, the second circuit unit 200 and the third circuit unit 300 are the second battery 30 from the first battery 20. It may be characterized by transferring energy to.

[Embodiment 4]

As illustrated in FIG. 2, the third circuit unit 300 may include at least one mode switching switch 330 that switches circuit connection according to a driving mode signal.

The third circuit unit 300 includes a first semiconductor switch 311 and a second semiconductor switch 312 connected in series to both ends of the DC link, a first capacitor 341 and a second capacitor connected in series to both ends of the DC link. Capacitor 342, a third capacitor 343 having a negative terminal and a negative terminal of the DC link, an inductor 320 having one end connected to a node to which the first semiconductor switch 311 and the second semiconductor switch 312 are connected. ), The mode switching switch 330, which is connected to the other end of the inductor 320, and the third capacitor 343 may be connected to the second power supply 30 in parallel. .

In addition, the first capacitor or the second capacitor generally has a capacitance of about 1/20 to 1/10 compared to that of a large-capacity smoothing capacitor used in a DC link. For example, in the prior art, the required capacitance is 3,500 μF when 3.3 kW, DC link voltage is 350 V, and 7% error of 2% is allowed, but in the case of the present invention, the first and second capacitors require about 300 μF. There is an effect that can satisfy the specifications. That is, the present invention uses only about one-tenth or about one-fifth of the capacitors of large-capacity smoothing capacitors commonly used in DC links. When a large-capacity smoothing capacitor is used, it has the same amount of voltage ripple component as the amount of ripple component of the DC link voltage, and has the effect of obtaining an equal smoothing degree.

Also, the first circuit unit may be a single-phase AC / DC PWM converter. The first circuit portion may make the phases of the input voltage and current the same.

Also, the second circuit unit may be a circuit having two transformers facing each other, centered on one transformer.

In addition, the second circuit part may further include an inductor between the transformer and at least one side of the single-phase converter.

[Embodiment 5]

When the operation mode signal is in the first mode, the other end of the mode changeover switch 330 is connected to a node (node a) to which the negative terminal of the first capacitor 341 and the positive terminal of the second capacitor 342 are connected. It can be characterized by being connected.

The first circuit unit 100 and the second circuit unit 200 transfer energy in one or both directions between the power supply 2 and the first battery 20, and the control unit controls the AC component of the DC link voltage. In order to remove, the first semiconductor switch 311 and the second semiconductor switch 312 of the third circuit unit 300 may be controlled.

[Embodiment 6]

The control unit may include the first semiconductor such that the voltage Vc1 of the first capacitor 341 connected to the upper side and the voltage Vc2 of the second capacitor 342 connected to the lower side are Equations 1 and 2, respectively. The switch 311 and the second semiconductor switch 312 may be controlled.

, [Equation 1]

,

,[Equation 2]

,

,

이며, Vs, Is, ω는 각각 상기 전원(2)의 전압 RMS값, 전류의 RMS값, 상기 전원(2)의 각주파수(=2π×전원 주파수)이고, Cr은 상기 제 1 커패시터(341) 및 상기 제 2 커패시터(342)의 커패시턴스 값이며, Lr은 상기 인덕터(320)의 인덕턴스 값이다.here,

,

Where Vs, Is, and ω are the voltage RMS value of the power supply 2, the RMS value of the current, and the angular frequency of the power supply 2 (= 2π × power frequency), and Cr is the first capacitor 341 And the capacitance value of the second capacitor 342, and Lr is the inductance value of the inductor 320.

The first and second capacitor voltages Equations 1 and 2 may be derived so that only DC power remains in the DC link from the power ripple component, which is a time-varying term of the instantaneous input power of the first circuit.

[Embodiment 7]

As shown in FIG. 5, when the operation mode signal is in the first mode, the controller may input a DC link voltage error that is a difference between a DC link voltage command value (Vdc *) and a DC link voltage (Vdc) as an input. A voltage controller 350; And a third current controller 360 that takes the output of the third voltage controller 350 as an input and generates control signals of the first and second semiconductor switches 311 and 312 of the third circuit unit. .

The third voltage controller 350 includes a compensation target voltage generator 351 that takes a DC link voltage error as an input and generates a compensation target voltage Vr for removing an AC component of the DC link voltage; And a controller 352 for calculating the current command value I_Lr * of the inductor 320 based on the difference between the zero command value and the compensation target voltage Vr.

In addition, the first mode is a 1-1 mode for transferring energy from the power source 2 to the first battery 20; and a 1-2 for transferring energy from the first battery 20 to the power source 2 Mode; may be characterized by including.

In addition, the compensation target voltage generation unit 351, a time delay unit 351a for inputting a DC link voltage error; and the DC link voltage error signal and the output signal of the time delay unit 351a as input. And, it may be characterized in that it comprises a frequency converter 351b for calculating the compensation target voltage (Vr).

In addition, the time delay unit 351a is characterized in that to delay the time (1 / (8f)) corresponding to a quarter cycle based on the frequency 2f of the frequency f of the power source 2 Can be done with

으로 디지털적으로 구현된 것을 특징으로 할 수 있다. 여기서, n은 fs/(8f), fs는 샘플링 주파수인 것을 특징으로 할 수 있다. The time delay unit (351a)

It can be characterized by digitally implemented. Here, n is fs / (8f), and fs is a sampling frequency.

Due to this feature, a vector signal that rotates the scalline DC link voltage error by generating a 1/4 cycle delay signal for a frequency 2f component of the frequency f of the power supply 2 of the DC link voltage error And may have an effect of easily converting frequencies based on this.

In addition, the frequency converter 351b, the DC link voltage error signal and the output signal of the time delay unit 351a as input, DC having a frequency twice the frequency (f) of the power supply (2) The voltage of the compensation target voltage Vr may be calculated by frequency-converting the component of the link voltage error Vdc_err to a component having the frequency f of the power supply 2.

In the 1-1 mode in which energy is transferred from the power source 2 to the first battery 20, the frequency converter 351b generates a voltage Vr to be compensated using Equation 3, and the first battery ( In the first or second mode in which energy is transferred from 20) to the power supply 2, the voltage Vr to be compensated may be generated using Equation (4).

,[Equation 3]

,

.[Equation 4]

.

Here, ω is the angular frequency (2πf) of the power supply 2.

Further, Vr = [1 0] · T (ωt) · Vdc_dq or Vr = [0 1] · T (ωt) · Vdc_dq may be determined, where Vdc_dq = [Vdc_err Vdc_err_delay] ^T and Vdc_err_delay are the time delay units By (351a), Vdc_err is a time delayed value.

The frequency converter 351b is a coordinate system that rotates at the frequency f of the power supply 2, and a frequency component twice the frequency f of the power supply 2 is the frequency converter or the coordinate converter 351b. By this, it has the same frequency component as the frequency f of the power supply 2.

Due to this feature, it is possible to easily obtain the compensation target voltage Vr of the same frequency as the power source frequency f in real time.

In addition, the controller 352 for calculating the current command value (I_Lr *) of the inductor 320 is an error obtained by subtracting the compensation target voltage (Vr) from a command value of 0 as an input, and the current command value of the inductor 320 It may be a Proportional-Resonant (PR) controller that outputs (I_Lr *). The proportional resonance controller may be a sum of a proportional controller and at least one resonance controller.

The resonance frequency of the resonance controller may be the same as that of the power source 2.

The resonance frequency of the resonance controller may be characterized in that it is the nth order high frequency of the frequency of the power supply 2. Where n = 1, 2, 3, ...

The PR controller may be characterized by including a plurality of resonance controllers.

The plurality of resonance controllers may be characterized by having a plurality of different resonance frequencies.

The plurality of different resonance frequencies of the plurality of resonance controllers may include the power source 2 frequency.

All of the different resonant frequencies may be characterized in that they are frequencies that are multiples of the power source frequency.

In addition, the third current controller 360 includes: a proportional controller 361 that inputs the difference between the current command value I_Lr * and the measured value I_Lr of the inductor 320; A divider 362 for calculating a value obtained by dividing the output of the proportional controller 361 by a DC link voltage; And a PWM generator 363 outputting ON / OFF control signals of the first and second semiconductor switches 311 and 312 of the third circuit unit based on the output of the divider 362. have.

In addition, when the operation mode signal is in the first mode, the control unit includes a first voltage controller 110 that inputs a DC link voltage error that is a difference between a DC link voltage command value (Vdc *) and a DC link voltage (Vdc). ; It may be characterized in that it further comprises; a first current controller 120 that takes the output of the first voltage controller 110 as input and generates control signals S11 to 14 of the semiconductor switches of the first circuit unit.

In addition, the first voltage controller 110, the proportional integration controller 111 that takes the DC link voltage error as an input; A phase angle detector 112 that detects the phase θs of the voltage vs of the power supply 2 and calculates cos (θs); And a multiplier 113 that multiplies the output signal of the proportional integral controller 111 and the cos (θs) signal calculated by the phase angle detector to calculate the power command value (Is *) of the power supply 2. Can be done with

In addition, the first current controller 120 includes a proportional resonance controller 121 that inputs the difference between the current command value (Is *) of the power supply 2 and the current (Is) of the power supply 2; A divider 122 that calculates a value obtained by dividing the output of the proportional resonance controller 121 by a DC link voltage (Vdc); And a PWM generator 123 generating control signals S11 to 14 of the semiconductor switches of the first circuit part based on the output of the divider.

In addition, when the driving mode signal is the first mode, the control unit, the battery current command generator 210 for generating a battery current command (Iho *); and the battery current command (Iho *) as an input, the second And a second current controller 220 generating control signals S21 to 28 of the semiconductor switches of the circuit unit.

The second current controller 220 includes a proportional controller 221 that uses the battery current command (Iho *) as an input; and control signals of semiconductor switches of the second circuit unit based on the output of the proportional controller 211 ( It may be characterized in that it comprises a PWM generator 222 for generating S21 ~ 28).

As shown in FIG. 6, the battery current command generator 210 has a predetermined current set in the case of a 1-1-1 mode in which the first battery 20 is charged with a constant current by the energy of the power source 2 A charging current command generation unit 211 for outputting a value; In the case of 1-1-2 mode in which the first battery 20 is charged with the constant voltage by the energy of the power source 2, the difference between the voltage command value (Vho *) of the first battery 20 and the voltage measurement value (Vho) is input. A first battery 20 voltage controller 212 including a proportional integral controller; Discharge current for outputting a value obtained by dividing the transmission power command value (P *) by the voltage (Vho) of the first battery 20 in the case of the first or second mode in which the energy of the first battery 20 is transferred to the power source 2 Command generation unit 213; And one of the outputs of the charging current command generation unit 211, the first battery voltage controller 212, and the discharge current command generation unit 213 according to the operation mode signal Mode as the battery current command (Iho *). It may be characterized in that it comprises a charging and discharging mode switching unit 214 to output.

[Embodiment 8]

As shown in FIG. 4, when the driving mode signal is in the second mode, the other end of the mode changeover switch 330 may be connected to the positive terminal (node b) of the third capacitor 343. have.

When the operation mode signal is in the second mode, the second circuit unit 200 transfers energy from the first battery 20 to the DC link, and the third circuit unit 300 receives the second circuit unit from the DC link. 2 may be characterized by transferring energy to the battery (30).

As shown in FIG. 7, when the operation mode signal is in the second mode, the control unit includes a DC link voltage controller 230 that controls the semiconductor switch of the second circuit unit based on the DC link voltage control error; A second battery charging current command generator 370 generating a charging current command Ilo * of the second battery 30; and a second battery charging current command that is an output of the second battery charging current command generator 370 ( Ilo *) may further include a second battery charging current controller 380 that generates control signals S31 and S32 of the semiconductor switches of the third circuit unit.

In addition, the DC link voltage controller 230 is a proportional integral controller 231 that inputs the difference between the DC link voltage command (Vdc *) and the DC link voltage (Vdc); and the output of the proportional integral controller 231 It may be characterized in that it further comprises a PWM generator 232 for generating the control signals (S21 ~ 28) of the semiconductor switches of the second circuit portion.

In addition, the second battery charging current controller 380 inputs the difference between the second battery charging current command Ilo * and the second battery charging current Ilo, which are the output of the second battery charging current command generator 370. And a PWM generator 382 that generates control signals (S31, S32) of semiconductor switches of the third circuit unit based on the output of the proportional integration controller 381. Can be done with

In addition, the second battery charging current command generator 370, as shown in FIG. 8, is set in advance in the case of the 2-1 mode in which the second battery 30 is charged with the constant current with the energy of the first battery 20 A charging current command generation unit 371 for outputting a predetermined current value; In the case of the 2-2 mode in which the second battery 30 is charged with the constant voltage by the energy of the first battery 20, the difference between the voltage command value (Vlo *) of the second battery 30 and the voltage measurement value (Vlo) is input. A second battery 30 including a proportional integral controller, a voltage controller 372; And a charging mode switching unit 373 that outputs one of the outputs of the charging current command generation unit 371 and the second battery voltage controller 372 as a battery current command (Ilo *) according to a driving mode signal (Mode). It may be characterized by including.

Here, the charging and discharging mode switching unit 214 and the charging mode switching unit 373 may be implemented by hardware or software.

The present invention described above is not limited by the above-described embodiments and the accompanying drawings, and various substitutions, modifications and changes are possible within the scope of the present invention without departing from the technical spirit of the present invention. It will be obvious to those who have the knowledge of.

1: Electric vehicle
2: Power
10: on-board charger
11: AC / DC rectifier and power factor correction
12: DC smoothing capacitor
13: Isolated DC / DC converter
20: high voltage battery
30: auxiliary battery
40: DC / DC converter for auxiliary battery charging
100: first circuit part
110: first voltage controller
120: first current controller
200: second circuit unit
210: battery current command generator
211: charging current command generation unit
212: first battery voltage controller
213: discharge current command generation unit
214: charging and discharging mode switching unit
220: second current controller
230: DC link voltage controller
231: proportional integral controller
232: PWM generator
300: third circuit part
311: first semiconductor switch
312: second semiconductor switch
320: inductor
330: mode change switch
341: first capacitor
342: second capacitor
343: third capacitor
350: third voltage controller
351: voltage generation unit to be compensated
351a: Time delay unit
351b: frequency converter
352: proportional resonance controller
360: third current controller
361: proportional controller
362: divider
363: PWM generator
370: second battery charging current command generator
371: charging current command generation unit
372: second battery voltage controller
373: charging mode switching unit
380: second battery charging current controller
1000: charging system

Claims (14)

As a charging system for electric vehicles,
A first circuit unit 100 connected to the power supply 2 and including a function of converting an AC voltage into a DC voltage;
A second circuit unit 200 provided between the DC link connected to the other end of the first circuit unit 100 and the first battery 20, and charging or discharging the first battery 20;
A third circuit part 300 provided between the DC link and the second battery 30; And
In accordance with the driving mode signal, the first to third circuit unit (100, 200, 300) includes a control unit for controlling to charge or discharge the first battery 20, or to charge the second battery 30
Charging system for an electric vehicle, characterized in that.
According to claim 1,
When the driving mode signal is the first mode
The first circuit part 100 and the second circuit part 200 transfer energy from the power source 2 to the first battery 20 or energy from the first battery 20 to the power source 2. And
The third circuit 300 is an electric vehicle charging system characterized in that the AC current flows from the DC link or to the DC link so that the AC voltage component of the power source 2 does not appear in the DC link.

According to claim 1,
When the driving mode signal is the second mode,
The second circuit unit 200 and the third circuit unit 300 is an electric vehicle charging system, characterized in that for transferring energy from the first battery 20 to the second battery (30).
The method of claim 2 or 3,
The third circuit unit 300,
Charging system for an electric vehicle, characterized in that it comprises at least one mode switching switch 330 for switching the circuit connection according to the driving mode signal.
The method of claim 4,
The third circuit unit 300,
The first semiconductor switch 311 and the second semiconductor switch 312 connected in series to both ends of the DC link,
The first capacitor 341 and the second capacitor 342 connected in series to both ends of the DC link,
A third capacitor (343) connected to the negative terminal and the negative electrode of the DC link,
An inductor 320 having one end connected to a node to which the first semiconductor switch 311 and the second semiconductor switch 312 are connected,
The mode switching switch 330 is connected to the other end of the inductor 320,
Including,
The third capacitor 343 is a charging system for an electric vehicle, characterized in that connected to the second battery 30 in parallel.
The method of claim 5,
When the driving mode signal is the first mode,
The other end of the mode switching switch 330 is a charging system for an electric vehicle, characterized in that the negative terminal of the first capacitor 341 and the positive terminal of the second capacitor 342 are connected to a connected node.
The method of claim 6,
The first circuit part 100 and the second circuit part 200 transfer energy between the power source 2 and the first battery 20 in one direction or both directions,
The control unit controls the first semiconductor switch 311 and the second semiconductor switch 312 of the third circuit unit 300 to remove the AC component of the voltage Vdc of the DC link. Car charging system.
The method of claim 7,
The control unit,
A third voltage controller 350 that inputs a DC link voltage error that is a difference between the DC link voltage command value and the DC link voltage,
And a third current controller 360 that takes the output of the third voltage controller 350 as an input and generates control signals of the first and second semiconductor switches 311 and 312 of the third circuit unit 300;
The third voltage controller 350,
A compensation target voltage generator 351 which takes the DC link voltage error as an input and generates a compensation target voltage Vr for removing the AC component of the DC link voltage,
A controller 352 for calculating a current command value I_Lr * of the inductor 320 based on a difference between a zero command value and the compensation target voltage Vr;
The third current controller 360,
A controller 361 that inputs the difference between the current command value I_Lr * of the inductor 320 and the current measurement value I_Lr of the inductor 320,
A divider 362 for calculating a value obtained by dividing the output of the controller 361 by a DC link voltage, and
And a PWM generator 363 outputting a control signal for controlling ON / OFF of the first and second semiconductor switches 311 and 312 of the third circuit part based on the output of the divider 362
Charging system for an electric vehicle, characterized in that.
The method of claim 8,
The compensation target voltage generation unit 351,
Time delay unit (351a) for inputting the DC link voltage error, and
And a frequency conversion unit 351b for taking the DC link voltage error signal and the output signal of the time delay unit 351a as inputs and calculating the compensation target voltage Vr;
The time delay unit (351a),
Delaying the time (1 / (8f)) corresponding to a quarter cycle based on the frequency 2f twice the frequency f of the power supply 2;
The frequency converter 351b,
The DC link voltage error signal and the output signal of the time delay unit (351a) as input,
Frequency-converting the component of the DC link voltage error having a frequency twice the frequency (f) of the power supply (2) to a component having the frequency (f) of the power supply (2) to calculate the voltage to be compensated (Vr)
Charging system for an electric vehicle, characterized in that.
The method of claim 9,
The frequency converter 351b.
In the 1-1 mode in which energy is transferred from the power source 2 to the first battery 20, the voltage Vr to be compensated is generated using Equation 3 below,
In the 1-2 mode, in which energy is transferred from the first battery 20 to the power source 2, generating the voltage Vr to be compensated using Equation 4 below.
Charging system for an electric vehicle, characterized in that.
[Equation 3]

,
[Equation 4]

.
The method of claim 8,
The controller 352 for calculating the current command value (I_Lr *) of the inductor 320,
An error obtained by subtracting the voltage to be compensated from the command value of 0 is input,
A proportional resonance (PR) controller that outputs the current command value of the inductor 320;
The proportional resonance controller,
A proportional controller and at least one resonance controller;
The resonance frequency of the resonance controller,
Containing power (2) frequency
Charging system for an electric vehicle, characterized in that. The method of claim 5,
When the driving mode signal is the second mode,
The other end of the mode switch 330 is connected to the positive terminal of the third capacitor 343,
The second circuit unit 200 transfers energy from the first battery 20 to the DC link,
The third circuit 300 transmits energy from the DC link to the second battery 30
Charging system for an electric vehicle, characterized in that.
The method of claim 12,
The control unit,
A DC link voltage controller 230 that controls the semiconductor switch of the second circuit unit based on the DC link voltage control error that is the difference between the DC link voltage command value and the DC link voltage measurement value;
A second battery charging current command generator 370 generating a charging current command (Ilo *) of the second battery 30; and
A second battery charging current controller 380 generating control signals S31 and S32 of semiconductor switches of the third circuit unit based on the second battery charging current command that is the output of the second battery charging current command generator 370. What's more
Charging system for an electric vehicle, characterized in that.
The method of claim 13,
The second battery charging current command generator 370,
In the case of the 2-1 mode in which the second battery 30 is charged with the constant current by the energy of the first battery 20, the charging current command generation unit 371 which outputs a predetermined current value previously set,
In the case of the 2-2 mode in which the second battery 30 is charged with the constant voltage by the energy of the first battery 20, the difference between the voltage command value of the second battery 30 and the measured value of the second battery voltage is input. A second battery voltage controller 372 including a proportional integral controller, and
And a charging mode switching unit 373 which outputs one of the outputs of the charging current command generation unit 371 and the second battery voltage controller 372 as a battery current command according to the driving mode signal Mode.
Charging system for an electric vehicle, characterized in that.

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