On-board charging device control method and device for multiple energy supplies

Abstract

An exemplary control method for a bidirectional on-board charging device, or OBC for short, (20) may include: measuring a first voltage (V ac1, Sen ) of a first alternating current terminal, or AC terminal for short, which is connected to a first line (L1) of three-phase AC input lines (L1, L2, L3), and measuring a second voltage (V ac2, Sen ) a second AC terminal connected to a second line (L2) of the three-phase AC input lines (L1, L2, L3), and controlling a low-frequency branch from a plurality of branches provided in the bidirectional OBC (20) to be connected to the first AC terminal or the second AC terminal based on phase angles of the first voltage (V ac1, Sen ) and the second voltage (V ac2, Sen ) is synchronized.

Description

Technical FieldThe present disclosure and invention relates to a method and apparatus for controlling a multi-power supply onboard charger (OBC) for a plurality of power supplies for a plurality of power supplies.BackgroundIn general, an electric vehicle acquires the drive energy of an electric motor from a high-voltage battery and has to be recharged via a bidirectional electric vehicle supply device (EVSE) if the state of charge (SOC) of such a high-voltage battery falls below a threshold value.The high voltage battery in such an electric vehicle may operate as an energy storage system (ESS), and accordingly, the electric vehicle may provide a vehicle-to-grid (V2G) mode (V2G= Ve-To-Grid) that feeds the power / energy from the high voltage battery to the grid (system power) and a vehicle-to-load (V2L) mode (V2L=-To-Load) that supplies the power / energy of the high voltage battery to various electronic devices (e.g., home electronics). In this case, the household electronics may include a laptop, a fan, a refrigerator, a washing machine, a television, an electric heater, an electric rice cooker, a microwave, etc.An electric vehicle should have a bidirectional OBC to operate in a charging mode, a V2G mode, or a V2L mode. As an example of such a bidirectional OBC, Korean Patent Application No. 10-2023-0015763 (publication date: Jan. 31, 2023), entitled "Apparatus for Controlling On-Board Bidirectional Charging Device of Electric Vehicle and Method Therefor", discloses a method of forming an AC voltage having the same period and phase but different effective values (RMS values) at two terminals of a bidirectional OBC. This makes it possible to construct a system that supplies electric power to a plurality of electronic devices by increasing the output power of a single bidirectional OBC.However, in this technology, the two terminals necessarily have the same period and phase, and when different loads, particularly inductive and capacitive loads, are connected to each terminal, the phase difference of the electric current becomes significantly larger compared to the voltage formed by the OBC. In this case, there occurs a problem that distortion of the electric current occurs near the zero voltage of the V ac- phase voltage.Therefore, there is a need in the art for an OBC control technology that minimizes the distortion of the electric current caused by the phase difference of each phase when two different AC input terminals (AC input terminals) of a bidirectional OBC are used.Brief ExplanationThe present disclosure or invention (also only disclosure below) relates to a control method and a control device for a plurality of power supplies (e.g. power supplies). Particular embodiments relate to a control method and a control apparatus for a plurality of power supplies that minimize the distortion of the electric current caused by a phase difference of a load when a V2L function is operated.An embodiment of the present disclosure provides an OBC control technology that minimizes the distortion of the electric current caused by the positional difference of each phase when two different AC input terminals of a bidirectional OBC are used.A control method for an on-board charger (OBC) of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure may include a step of measuring a first voltage of a first AC terminal connected to a first line of three-phase AC input lines and measuring a second voltage of a second AC terminal connected to a second line of the three-phase AC input lines, and a step of controlling a low-frequency branch among a plurality of branches provided in the bidirectional OBC, so that it is synchronized with the first AC terminal or the second AC terminal based on phase angles of the first and second voltages.In this case, the bidirectional OBC may be provided with a three-phase bidirectional power factor correction (PFC), wherein a first switch and a fourth switch form a first arm, a second switch and a fifth switch form a second arm, a third switch and a sixth switch form a third arm, the first line is connected to the first arm, the second line is connected to the second arm, a third line different from the first line and the second line is connected to the third arm, and the low-frequency arm may be the third arm.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm or the second arm based on the phase angles of the first and second voltages.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm when the phase angle of the first voltage is faster than the phase angle of the second voltage.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the second arm when the phase angle of the second voltage is faster than the phase angle of the first voltage.In this case, the control method for controlling the bidirectional OBC may further include a step of generating a first control signal for controlling the switches of the first arm and a second control signal for controlling the switches of the second arm.In this case, the control method for controlling the bidirectional OBC may further include a step of generating a third control signal for controlling the switches of the third arm based on the phase angles of the first and second voltages.In this case, the control method for controlling the bidirectional OBC may further include a step of generating first to third pulse width modulation (PWM) signals by modulating pulse widths of first to third control signals, and a step of controlling the switches of the first to third arms based on the first to third PWM signals.Further, a control device for a bidirectional OBC of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure may include: a sensor portion that measures a first voltage using a voltage sensor connected to the electronic device connected to a first line of three-phase AC input lines and measures a second voltage using a voltage sensor connected to an electronic device connected to a second line of the three-phase AC input lines; and a controller that controls a low-frequency arm of a plurality of arms provided in a bidirectional OBC to be synchronized with the first AC terminal or the second AC terminal based on phase angles of the first and second voltages.In this case, the bidirectional OBC may include a three-phase bidirectional PFC, wherein a first switch and a fourth switch form a first branch, a second switch and a fifth switch form a second branch, a third switch and a sixth switch form a third branch, the first line is connected to the first branch, the second line is connected to the second branch, a third line different from the first line and the second line is connected to the third branch, and the low-frequency branch may be the third branch.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm or the second arm based on the phase angles of the first and second voltages.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm when the phase angle of the first voltage is faster than the phase angle of the second voltage.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the second arm when the phase angle of the second voltage is faster than the phase angle of the first voltage.In this case, the control device may generate a first control signal for controlling the switches of the first branch and a second control signal for controlling the switches of the second branch.In this case, the controller may generate a third control signal to control the switches of the third arm based on the phase angles of the first and second voltages.In this case, the controller may generate first to third PWM signals by modulating the pulse widths of the first to third control signals and control the switches of the first to third arms based on the first to third PWM signals.According to the embodiments of the present disclosure, the distortion of the electric current caused by a phase difference of each phase can be minimized when two different AC input terminals of the bidirectional OBC are used.In addition, the distortion of the electric current caused by the phase difference of the load in a dual V2L operation can be minimized, so that a stable current source can be provided and the power stability is increased.In addition, consumers can connect electrical devices to AC inputs without differentiating between capacitive and inductive loads, which increases comfort.In addition, no additional elements need to be added to reduce the distortion of the electric current caused by the phase difference of the loads, thereby reducing the cost.Brief Description of the DrawingsThe above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings: FIG. 1 is a block diagram illustrating a schematic configuration of a bidirectional onboard charger (OBC) control device for an eco-friendly vehicle according to an exemplary embodiment of the present disclosure. FIG. 2 is a circuit diagram of a bidirectional OBC control device for an eco-friendly vehicle according to the exemplary embodiment of FIG. 1. FIG. 3 is a view showing an example of the operation of a controller provided in a bidirectional OBC control device of an eco-friendly vehicle according to the exemplary embodiment of FIG. 1. FIGS. 4A to 4D are control diagrams indicating a step of generating a command current signal during the operation of a controller of FIG. 3. FIGS. 5A and 5B are views showing an example of a graph comparing the difference in distortion of electric current before and after application of a bidirectional OBC control device of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure. FIG. 6 illustrates a control method for a bidirectional OBC of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure.Detailed Description of Illustrative EmbodimentsHereinafter, exemplary embodiments disclosed in this specification will be described in detail with reference to the accompanying drawings, the same or similar components are denoted by the same reference numerals, and duplicate descriptions thereof will be omitted. The suffix "module" and "part" of the components used in the following description are given or used only in consideration of the convenience of making the description, and have no meanings or roles that are distinguished from each other. In addition, when it is determined that the detailed explanation of the related art technology in the explanation of the exemplary embodiments disclosed in this specification may obscure the gist of the exemplary embodiments disclosed in this specification, the detailed description is omitted. In addition, the accompanying drawings are intended only to facilitate understanding of the exemplary embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the accompanying drawings and should be understood to include all modifications, equivalents, or substitutes included within the spirit and technical scope of the present disclosure.Terms having ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only to distinguish the individual components.When it is said that one component is "connected" or "coupled / coupled" to another component, it is understood that the component may be directly connected or coupled / coupled to that other component, but that another component may also be present therebetween. On the other hand, when it is said that one component is "directly connected" or "directly coupled / coupled" to another component, it is assumed that no other component exists therebetween.Terms in the singular include terms in the plural, unless the context clearly indicates otherwise.In this specification, terms such as "comprise" or "comprise" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and are not to be understood as excluding the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.FIG. 1 is a block diagram illustrating a schematic configuration of an on-board charger (OBC) control device 100 for an eco-friendly vehicle according to an exemplary embodiment of the present disclosure.Referring to FIG. 1, the bidirectional OBC (also, for example, bidirectional OBC) control device for an eco-friendly vehicle according to the present exemplary embodiment may include a storage portion 10, a bidirectional OBC 20, an outdoor power outlet 30 (for example, an outdoor power outlet or the like), an indoor power outlet 40 (for example, an indoor power outlet or the like), a high-voltage battery 50, and a controller 60.In this case, each component may be combined with each other to be realized as one body, or some components may be omitted depending on the manner of realizing the bidirectional OBC control device according to the present exemplary embodiment.FIG. 2 is a circuit diagram of a bidirectional OBC control device 100 for an eco-friendly vehicle according to the exemplary embodiment of FIG. 1.Hereinafter, the components of the bidirectional OBC control device of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure will be described in detail with reference to FIGS. 1 and 2.The storage section 10 may store various logics, algorithms, and programs required in the process of measuring the demand current of electronic devices connected to the outdoor power outlet and the indoor power outlet among the three-phase AC input lines and controlling the bidirectional OBC based on the demand current.The storage section 10 may store a reference inter-circuit voltage (V link,ref), a dq-converted reference voltage (V ac1,dq,ref) of an outdoor power outlet 30, a dq-converted reference voltage (V ac1,dq,ref) of an indoor power outlet 40, a reference frequency (f ac1,ref) of the AC voltage supplied to the outdoor power outlet 30, and a reference frequency (f ac2,ref) of the AC voltage supplied to the indoor power outlet 40.Here, the dq transformation may mean that a three-phase AC voltage is converted into a two-phase, one of the three phases being aligned with the x-axis (a reference axis) and the remaining ones being converted into a second phase on the basis of the axis aligned with the x-axis. When the three phases are converted into two phases by the dq transformation described above, it is possible to control within a two-dimensional orthogonal coordinate with which we are familiar, which facilitates control.The storage portion 10 may include at least one kind of storage medium such as a flash memory, a hard disk, a micro memory, a secure digital card (SD) card, or an eXtream digital card (XD) card, and a memory such as a random access memory (RAM), a static RAM (SRAM), a read only memory (ROM), a programmable ROM (PROM), an electrically erasable ROM (EEPROM), a magnetic memory (MRAM), a magnetic disk, or an optical disk.The bidirectional OBC 20 may charge not only the high-voltage battery 50 by converting alternating current into direct current, but also supply the electric power to a power system (or bidirectional EVSE) by converting the direct current of the high-voltage battery 50 into alternating current (having the same voltage and frequency as the grid current).The bidirectional OBC 20 may include a three-phase bidirectional power factor correction PFC 210, a bidirectional DC / DC converter 220, a first voltage sensor 230, a second voltage sensor 240, a high-voltage AC connector 250, and an input filter 260. The three-phase bidirectional PFC 210 may be a module for increasing energy efficiency, and may include a first current sensor 211 for measuring the inductance current of an L1 line, a second current sensor 212 for measuring the inductance current of an L2 line, and a third voltage sensor 213 for measuring the DC link voltage. Here, the three-phase bidirectional PFC 210 may perform AC / DC power conversion, power factor correction, and reactive power minimization. The bidirectional DC / DC converter 220 may stably supply the power of the high-voltage battery 50 to the power grid system, the outdoor power outlet 30, or the indoor power outlet 40, or may stably supply the power supplied from an electric vehicle supply device (EVSE) to the high-voltage battery 50. The first voltage sensor 230 may measure a voltage of the single-phase AC charging line L 1 during the single-phase charging. The second voltage sensor 240 may measure a voltage of the L2 line or a voltage of the L3 line among the three-phase AC input lines. The high voltage AC connector 250 may connect the vehicle charging port and the interior power outlet 40 to the bidirectional OBC 20. The input filter 260 may remove the noise of the alternating current supplied from the EVSE. An N line may refer to an N-phase line (neutral conductor).The outdoor power outlet 30 may be a module detachably attached to the charging terminal of the electric vehicle, and may be connected to electronic devices (devices) for transmitting the power when the high-voltage battery 50 is not charged.The interior power outlet 40 may be disposed in the electric vehicle and may transmit the power (e.g., current and voltage) of the high voltage battery 50 to the connected electronic devices. In this case, the pipe L' supplying power to the indoor flow outlet 40 may be branched from the L2 pipe or the L3 pipe.Further, the controller 60 may take over overall control to ensure that each of the above components properly performs its own functions. Such a control device 60 may be implemented in the form of hardware, in the form of software or in the form of a combination of hardware and software. Preferably, the controller 60 may be a microprocessor, but is not limited thereto.Specifically, the controller 60 may measure a first voltage that is a voltage of an electronic device connected to the first line L 1 among the three-phase AC input lines L 1, L 2, and L 3 and a second voltage that measures a voltage of an electronic device connected to the second line L 2 among the three-phase AC input lines L 1, L 2, and L 3, and the controller 60 may perform various controls in the process of controlling the bidirectional OBC based on the first voltage and the second voltage.In this case, the controller 60 may control the bidirectional OBC based on the phase angles of the first and second voltages.Further, as shown in FIG. 2, the power to be supplied to the electronic device connected to the outdoor power outlet 30 (herein, also referred to as power only briefly) may be conducted through the input filter 260 via the line L 1, and the power to be supplied to the electronic device connected to the indoor power outlet 40 may be conducted through the input filter 260 via the line L 2. At this time, the controller 60 may open a switch connecting the line L 1 and the line L 2 and close a switch disposed on the line L 2 between the high-voltage AC connector 250 and the input filter 260.In order to power the electronic device connected to the outdoor power outlet 30 and the electronic device connected to the indoor power outlet 40, the controller 60 may perform operations as illustrated in FIG. 3 below.The controller 60 may control the specific switches Q 1 and Q 4 of the three-phase bidirectional PFC 210 to supply power (current and voltage) to the electronic device connected to the outdoor power outlet 30, and may control the specific switches Q 2 and Q 5 of the three-phase bidirectional PFC 210 to supply power to the electronic device connected to the indoor power outlet 40. At the same time, the switches Q 3 and Q 6 can be used to determine the leading current (also e.g. leading current).FIG. 3 is a view showing an example of the operation of a controller provided in a bidirectional OBC control device of an eco-friendly vehicle according to the exemplary embodiment of FIG. 1.Referring to FIG. 3, the controller 60 may first extract a phase (θ ac1) from the L1 voltage (V ac1, Sen), which is measured by the first voltage sensor 230, based on a phase-locked loop (PLL) to power the electronic device connected to the outdoor power outlet 30 (S 305).In addition, the controller 60 may perform dq transformation on both the inductance current (I ac1,sen) measured by the first current sensor 211 and the inductance current (I ac2,sen) measured by the second current sensor 212 so as to be synchronized with the phase (θ ac1) (S 310).Here, in this specification, the dq-transformed current of the inductor current (I ac1,sen) is defined as a first current (I ac1,dq,sen) and the dq-transformed current of the inductor current (I ac2,sen) is defined as the second current (I ac2,dq,sen).In addition, the controller 60 may determine (e.g., determine / establish) a first reference current (I ac1,dq,ref) that causes the DC link voltage (V link,sen) measured in the third voltage sensor 213, to follow the reference voltage (V link,ref) related to the DC link voltage (S 315). In this case, the first reference current is a dq-transformed reference current.In addition, the controller 60 may generate a first d-axis current control signal (U d1) and a first q-axis current control signal (U q1) that cause the first currents (I ac1,dq,sen) to follow the first reference currents (I ac1,dq,ref) (S 320).In addition, the controller 60 may perform the DQ-to-ABC transformation of the first d-axis current control signal (U d1) and the first q-axis current control signal (U q1) based on the phase (θ ac1) thereby generating a first control signal (U A1) (S 325).Further, the controller 60 may generate a first PWM signal by performing the PWM on the first control signal (U A1) S 330 and controlling the switches Q 1 and Q 4 of the three-phase bidirectional PFC 210 based on the first PWM signal (S 335).Meanwhile, in an effort to power the electronic device connected to the indoor power outlet 40, the controller 60 may perform the DQ transformation to the L2 voltage (V ac2,sen), which is measured by the second voltage sensor 240, so as to be synchronous with the phase (θ ac1) (S 340). In this case, the dq-transformed L2 voltage (V ac2,sen) may be referred to as a second voltage (V ac2,dq,sen).In addition, the controller 60 may determine (e.g., determine) a second reference current (I ac2,dq,ref) that causes the second voltage (V ac2,dq,sen) to follow the dq-transformed reference voltages (V ac2,dq,ref) of the indoor power outlet 40 stored in the storage portion 10 (S 340). In this case, the second reference current may be the dq-transformed reference current.In addition, the controller 60 may determine (e.g., determine) a second d-axis current control signal (U d2) and a second q-axis current control signal (U q2) that cause the dq-transformed second current (I ac2,dq,sen) of the inductor current (I ac2,sen) measured by the second current sensor 212 to follow the second reference current (I ac2,dq,ref) (S 345).In addition, the controller 60 may perform the DQ-to-ABC transformation on the second d-axis current control signal (U d2) and the second q-axis current control signal (U q2) in a state to be synchronized with the phase (θ ac1) (e.g., a state of synchronization with the phase (θ ac1)) thereby generating a second control signal (U A2) (S 350).Further, the controller 60 may generate a second PWM signal by performing PWM on the second control signal (U A2) S 355, and may control the switches Q 2 and Q 5 of the three-phase bidirectional PFC 210 based on the second PWM signal (S 360).Further, the controller 60 may generate a command current determination signal based on the first control signal (U A1) generated in step S 325 and the second control signal (U A2) generated in step S 350 (S 365), and perform the PWM on the command current determination signal, thereby generating a third PWM signal S 370, and control the switches Q 3 and Q 6 of the three-phase bidirectional PFC 210 based on the third PWM signal (S 375).Here, the command current determination signal may be a signal generated by selecting a control signal belonging to a terminal having a faster phase from the first control signal (U A1) or the second control signal (U A2).In this case, the third PWM signal for controlling the switches Q 3 and Q 6 may be a signal synchronized with the first PWM signal for controlling the switches Q 1 and Q 4 when the phase (θ ac1) of the L 1 voltage (V ac1,sen) is faster than the phase (θ ac2) of the L 2 voltage (V ac2,sen).In contrast, the third PWM signal for controlling the switches Q 3 and Q 6 may be a signal synchronized with the second PWM signal for controlling the switches Q 2 and Q 5 when the phase (θ ac2) of the L 2 voltage (V ac2,sen) is faster than the phase (θ ac1) of the L 1 voltage (V ac1,sen).FIGS. 4A to 4D are control diagrams indicating a step of generating a command current signal during the operation of a controller of FIG. 3.First, as shown in FIG. 4A, the controller 60 may generate a sample and hold signal (U A2_alt) by passing the second control signal (U A2) through a sample and hold circuit.In this case, the sample and hold circuit may be a circuit that holds the input signal for a certain period of time, so that the sample and hold signal (U A2_alt) may have the same value as the second control signal (U A2) at any time in the past.In addition, the controller 60 may input the second control signal (U A2) to the (+) terminal (i.e., positive input, for example) of a comparator circuit and input the value "0" to the (-) terminal (i.e., negative input, for example) of the comparator circuit, thereby outputting a first comparison signal (see FIG. 4B ).In addition, the controller 60 may input the value "0" to the (+) terminal of the comparator circuit and input the sample and hold signal (U A2_alt) to the (-) terminal of the comparator circuit, thereby outputting a second comparison signal.In addition, the controller 60 may input the first comparison signal and the second comparison signal to an AND gate, and output a zero detection signal (zero_Detect_Signal) as an output signal.Here, the zero detection signal (zero_Detektion_Signal) may have a value of "0" when at least one of the second control signal (UA 2) and the sample and hold signal (U A2_old) has a value of "0", and may output a non-zero value only when both have a value other than "0".Thus, the zero detection signal (zero_Detect_Signal) can detect a zero voltage rising portion of the L2 voltage.In addition, as shown in FIG. 4C, the controller 60 may input a first threshold value to the (+) terminal of the comparator circuit and input the first control signal (U A1) to the (-) terminal of the comparator circuit, thereby outputting a third comparison signal.In this case, the first threshold may have various negative values and have a value of "-0.005", for example, as shown in FIG. 4C.In this case, the controller 60 may input the zero detection signal (zero_Detect_Signal) and the third comparison signal to the AND gate, and then input the output signal to the S input terminal (i.e., the S input, for example) of the RS flip-flop.In addition, the controller 60 may input the first control signal (U A1) to the (+) terminal of the comparator circuit and input a second threshold value to the (-) terminal of the comparator circuit, thereby outputting a fourth comparison signal.In this case, the second threshold may have various positive values, and for example, a value of "0.005" as shown in FIG. 4C.In this case, the controller 60 may input the zero detection signal (zero_Detect_Signal) and the fourth comparison signal to the AND gate, and then input the output signal to the R input terminal (i.e., the R input, for example) of the RS flip-flop.In addition, the controller 60 may output a low-frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) that is an output signal of the Q output terminal (i.e., the Q output, for example) of the RS flip-flop.In this case, the low-frequency branch control signal (Niedrig_Frequenz_Zweig_Strg) may be set when the first comparison signal at the time when the zero detection signal (zero_Detection_Signal) occurs is less than the first threshold.Further, the low frequency branch control signal (Niedrig_Frequenz_Zweig_Strg) may be reset when the first comparison signal is greater than the second threshold at the time when the zero detection signal (zero_Detect_Signal) occurs.That is, the low frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) may have a value of "0" when the phase of the L1 voltage (V ac1,sen) is faster than the phase of the L2 voltage (V ac2,sen), and the low frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) may have a value of "1" when the phase of the L2 voltage (V ac2,sen) is faster than the phase of the L1 voltage (V ac1,sen).In addition, the controller 60 of FIG. 4D may use the first control signal and the second control signal as input signals of a 2-to-1 multiplexer and use the low-frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) as a selection signal, thereby outputting a command current detection signal (V a_positiv) as an output signal.Here, the command current determination signal (V a_positiv) may output the value of the first control signal (U A1) when the low-frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) is "0", and the command current determination signal (V a_positiv) may output the value of the second control signal (U A2) when the low-frequency arm control signal (Niedrig_Frequenz_Zweig_Strg) is "1".FIGS. 5A and 5B show an example of a curve in which the difference in electric current distortion before and after application of the bidirectional OBC controller of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure is compared.In the examples of FIGS. 5A and 5B, the vehicle may perform dual V2L control that outputs a voltage of 220V.Here, two V2L voltage terminals may be connected to the vehicle, the first terminal being connected to an inductive load having an apparent current of 16A and a phase of 60 degrees, and the second terminal being connected to a capacitive load having an apparent current of 16A and a phase of -60 degrees.FIG. 5A is a graph showing the change in the electric voltages measured by the voltage sensors connected to the loads of the first terminal and the second terminal, and FIG. 5B is a graph showing the change in the electric currents derived from the currents measured by the current sensors connected to the loads of the first terminal and the second terminal.The period 510 may show the change in the voltage of the loads connected to the first terminal and the second terminal in a conventional vehicle to which the command current determination control of embodiments of the present disclosure is not applied, and the period 530 may show the change in the voltage of the loads connected to the first terminal and the second terminal in the vehicle to which the command current determination control of embodiments of the present disclosure is applied.Referring to FIG. 5A, it can be seen that the voltage of the load connected to the first terminal and the voltage of the load connected to the second terminal almost coincide as a graph.In addition, in FIG. 5B, the period 550 may show the change in the electric current of the loads connected to the first terminal and the second terminal in a conventional vehicle to which the command current determination control of embodiments of the present disclosure is not applied, and the period 570 may show the change in the electric current of the loads connected to the first terminal and the second terminal in the vehicle to which the command current determination control of embodiments of the present disclosure is applied.Referring to FIG. 5B, the current distortion of the load connected to the second terminal of the vehicle to which the command current determination control of embodiments of the present disclosure is applied can be significantly improved compared to the load connected to the second terminal of the conventional vehicle.In Table 1 below, distortion (total harmonic distortion (total distortion factor), THD) of the first and second terminals in a conventional vehicle that do not perform the command current determination control according to an embodiment of the present disclosure may be compared with distortion of the first and second terminals in a vehicle that performs the command current determination control according to an embodiment of the present disclosure. Table 1 Table 1THD of a voltage of the first terminal1,77%2,02%THD of a current of the first terminal2,13%1,77%THD of a voltage of the second terminal1,47%1,62%THD of a current of the second terminal17,53%9,04%Magnitude of distortion current30A6AIt is apparent from Table 1 that the electric current of the second terminal of the vehicle to which the command current determination control of embodiments of the present disclosure is applied may have significantly improved current distortion compared to the electric current of the second terminal of the conventional vehicle. FIG. 6 illustrates a control method for a bidirectional OBC of an eco-friendly vehicle according to an exemplary embodiment of the present disclosure.The control method of a bidirectional OBC of an eco-friendly vehicle according to the present exemplary embodiment may be performed by the bidirectional OBC control device 100 of the eco-friendly vehicle in FIG. 1.Referring to FIG. 6, the bidirectional OBC control device 100 may measure a first voltage from a voltage sensor connected to an electronic device connected to the first line L 1 among the three-phase AC input lines L 1, L 2, and L 3, and may measure a second voltage from the voltage sensor connected to an electronic device connected to the second line L 2 among the three-phase AC input lines L 1, L 2, and L 3 (S 610).Further, the bidirectional OBC control device 100 may generate a first control signal for controlling switches of the first arm and a second control signal for controlling switches of the second arm (S 630).In this case, the bidirectional OBC control device 100 may be provided with a three-phase bidirectional PFC, wherein a switch Q 1 and a switch Q 4 form a first arm (also called a string), a switch Q 2 and a switch Q 5 form a second arm, a switch Q 3 and a switch Q 6 form a third arm, the first line L 1 is connected to the first arm, the second line L 2 is connected to the second arm, and the third line L 3 different from the first line L 1 and the second line L 2 is connected to the third arm.In addition, the bidirectional OBC control device 100 may generate a third control signal to control the switches of the third arm based on the phase angles of the first and second voltages (S 650).Further, the bidirectional OBC control device 100 may generate first to third PWM signals by modulating the pulse widths of the first to third control signals (S 67).In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm or the second arm based on the phase angles of the first and second voltages.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the first arm when the phase angle of the first voltage is faster than the phase angle of the second voltage.In this case, the switches of the third arm may be controlled to be synchronized with the switches of the second arm when the phase angle of the second voltage is faster than the phase angle of the first voltage.In addition, the bidirectional OBC control device 100 may control the switches of the first to third arms based on the first to third PWM signals (S 1690).According to the exemplary embodiments of the present disclosure described thus far, current distortion caused by a phase difference of each phase can be minimized when two different AC input terminals of the bidirectional OBC are used.In addition, current distortion caused by the phase difference of the loads in a dual V2L operation can be minimized, so that a stable current source is operated and power stability is increased.In addition, loads can connect electrical devices to AC inputs without differentiating between capacitive and inductive loads, which increases comfort.In addition, it is not necessary to add a separate additional element to reduce the current distortion caused by the phase difference of the load, thereby reducing the cost.Further, the above-described embodiments of the present disclosure may be implemented as computer readable code on a medium on which a program is recorded. The computer readable medium may include any type of recording device that stores computer system readable data. Examples of a computer readable medium may include hard disk drives (HDDs), solid state drives (SSDs), silicon disk drives (SDDs), ROM, RAM, CD-ROMs, magnetic tapes, floppy disks, optical storage devices, and the like. Therefore, the above detailed description is not to be taken in all respects as limiting and should be considered exemplary. The scope of the present disclosure should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present disclosure are included within the scope of the present disclosure.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedKR 10-2023-0015763

[0004]

Claims

A control method for an on-board bidirectional charger, OBC for short, (20), the method comprising: measuring a first voltage (V ac1, Sen) of a first AC terminal, AC terminal for short, connected to a first line (L1) of three-phase AC input lines (L1, L2, L3), and measuring a second voltage (V ac2, Sen) of a second AC terminal connected to a second line (L2) of the three-phase AC input lines (L1, L2, L3), and controlling a low frequency branch among a plurality of branches provided in the bidirectional OBC (20), so that it is synchronized with the first AC terminal or the second AC terminal based on phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control method according to claim 1, wherein: the bidirectional OBC (20) has three-phase bidirectional power factor correction, a first switch (Q1) and a fourth switch (Q4) define a first arm, a second switch (Q2) and a fifth switch (Q5) define a second arm, a third switch (Q3) and a sixth switch (Q6) define a third arm, the first line (L1) is connected to the first arm, the second line (L2) is connected to the second arm, and a third line (L3) different from the first line (L1) and the second line (L2) is connected to the third arm, and the low frequency arm is the third arm.The control method according to claim 2, wherein the third switch (Q3) and the sixth switch (Q6) of the third arm are controlled to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm or with the second switch (Q2) and the fifth switch (Q5) of the second arm based on the phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control method according to claim 3, wherein the third switch (Q3) and the sixth switch (Q6) of the third arm are controlled to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm if the phase angle (θ ac1) of the first voltage (V ac1, Sen) is faster than the phase angle (θ ac2) of the second voltage (V ac2, Sen).The control method according to claim 3 or 4, wherein the third switch (Q3) and the sixth switch (Q6) of the third arm are controlled to be synchronized with the second switch (Q2) and the fifth switch (Q5) of the second arm if the phase angle (θ ac2) of the second voltage (V ac2, Sen) is faster than the phase angle (θ ac1) of the first voltage (V ac1, Sen).The control method according to any one of claims 2 to 5, further comprising: generating a first control signal for controlling the first switch (Q1) and the fourth switch (Q4) of the first arm and a second control signal for controlling the second switch (Q2) and the fifth switch (Q5) of the second arm.The control method according to claim 6, further comprising: generating a third control signal for controlling the third switch (Q3) and the sixth switch (Q6) of the third arm based on the phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control method according to claim 7, further comprising: generating a first pulse width modulation signal, PWM signal for short, a second PWM signal, and a third PWM signal by modulating pulse widths of first to third control signals, and controlling the first switch (Q1) and the fourth switch (Q4) of the first arm, the second switch (Q2), and the fifth switch (Q5) of the second arm, and the third switch (Q3) and the sixth switch (Q6) of the third arm based on the first PWM signal, the second PWM signal, and the third PWM signal.A control device (100) for a bidirectional onboard charger, OBC for short, (20), the control device (100) comprising: a sensor system configured to measure a first voltage (V ac1,Sen) using a voltage sensor (230) connected to a first electronic device connected to a first line (L1) of three-phase alternating current (AC) power lines (L1, L2, L3), and configured to measure a second voltage (V ac2, Sen) using a voltage sensor (240) connected to a second electronic device connected to a second line (L2) of the three-phase AC power lines (L1, L2, L3), and a controller (60) configured to control a low frequency arm among a plurality of arms in the bidirectional OBC (20) to be synchronized with a first AC terminal or a second AC terminal based on phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control device (100) according to claim 9, wherein: the bidirectional OBC (20) has three-phase bidirectional power factor correction, a first switch (Q1) and a fourth switch (Q4) define a first branch, a second switch (Q2) and a fifth switch (Q5) define a second branch, a third switch (Q3) and a sixth switch (Q6) define a third branch, the first line (L1) is connected to the first branch, the second line (L2) is connected to the second branch, and a third line (L3) different from the first line (L1) and the second line (L2) is connected to the third branch, and the low frequency branch is the third branch.The control device (100) according to claim 10, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm or with the second switch (Q2) and the fifth switch (Q5) of the second arm based on the phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control device (100) according to claim 11, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm if the phase angle (θ ac1) of the first voltage (V ac1, Sen) is faster than the phase angle (θ ac2) of the second voltage (V ac2, Sen).The control device (100) according to claim 11 or 12, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the second switch (Q2) and the fifth switch (Q5) of the second arm if the phase angle (θ ac2) of the second voltage (V ac2, Sen) is faster than the phase angle (θ ac1) of the first voltage (V ac1, Sen).A control device (100) for an onboard bidirectional charger, OBC for short, (20) having three-phase bidirectional power factor correction, the control device (100) comprising: a sensor system configured to measure a first voltage (V ac1,Sen) using a voltage sensor (230) connected to a first electronic device connected to a first line (L1) of three-phase AC input lines (L1, L2, L3), and configured to measure a second voltage (V ac2, Sen) using a voltage sensor (240) connected to a second electronic device connected to a second line (L2) of the three-phase AC input lines (L1, L2, L3), measuring, and a controller (60) configured to: control a low frequency arm of a plurality of arms in the bidirectional OBC (20) to be synchronized with a first AC terminal or a second AC terminal based on phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen) wherein a first switch (Q1) and a fourth switch (Q4) define a first arm, a second switch (Q2) and a fifth switch (Q5) define a second arm, a third switch (Q3) and a sixth switch (Q6) define a third arm, wherein the first line (L1) is connected to the first arm, the second line (L 2) is connected to the second arm, and a third line (L 3) different from the first line (L 1) and the second line (L 2) is connected to the third arm, and the low frequency arm is the third arm, and generates a first control signal for controlling the first switch (Q 1) and the fourth switch (Q 4) of the first arm and a second control signal for controlling the second switch (Q 2) and the fifth switch (Q 5) of the second arm.The control device (100) according to claim 14, wherein the controller (60) is configured to generate a third control signal for controlling the third switch (Q3) and the sixth switch (Q6) of the third arm based on the phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control device (100) according to claim 15, wherein the controller (60) is configured to: generate a first pulse width modulation signal, PWM signal for short, a second PWM signal, and a third PWM signal by modulating pulse widths of first to third control signals, and control the first switch (Q1) and the fourth switch (Q4) of the first arm, the second switch (Q2) and the fifth switch (Q5) of the second arm, and the third switch (Q3) and the sixth switch (Q6) of the third arm based on the first PWM signal, the second PWM signal, and the third PWM signal.The control device (100) according to any one of claims 14 to 16, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm or with the second switch (Q2) and the fifth switch (Q5) of the second arm based on the phase angles of the first voltage (V ac1, Sen) and the second voltage (V ac2, Sen).The control device (100) according to claim 17, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the first switch (Q1) and the fourth switch (Q4) of the first arm if the phase angle (θ ac1) of the first voltage (V ac1, Sen) is faster than the phase angle (θ ac2) of the second voltage (V ac2, Sen).The control device (100) according to claim 17 or 18, wherein the controller (60) is configured to control the third switch (Q3) and the sixth switch (Q6) of the third arm to be synchronized with the second switch (Q2) and the fifth switch (Q5) of the second arm if the phase angle (θ ac2) of the second voltage (V ac2, Sen) is faster than the phase angle (θ ac1) of the first voltage (V ac1, Sen).

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