Charging device for electric vehicle

Abstract

A charging device for an electric vehicle according to an embodiment of the present invention includes: a supply module for a first mode for transmitting a first pulse wide modulation (PWM) signal to the outside; a charging module for a second mode for receiving a second PWM signal from the outside; and a control unit for controlling the supply module and the charging module, wherein the charging module includes a first line for receiving a connector proximity detection signal and a second line for receiving a control pilot signal, and the supply module includes a signal output unit for outputting the first PWM signal, a resistor unit disposed between the signal output unit and the second line, and a leakage current blocking unit disposed between the signal output unit and the resistor unit.

Description

Charging devices for electric vehicles

[0001] The present invention relates to electric vehicles, and more particularly to charging for electric vehicles.

[0002] Eco-friendly vehicles such as electric vehicles (EVs) or plug-in hybrid electric vehicles (PHEVs) use electric vehicle supply equipment (EVSE) installed at charging stations to charge their batteries.

[0003] To charge an EV, the EV and EVSE communicate via a charging connector connected between them. Once the charging connector is connected, charging begins after signaling is performed between the EVSE and EV.

[0004] The charging connector features a CP (control pilot) pin, through which a PWM (Pulse Wide Modulation) CP signal is transmitted from the EVSE to the EV. The interaction between the EVSE and the EV can be monitored and controlled through this CP signal, and the voltage level of the CP signal can vary depending on the charging state. Accordingly, the EV's charging device must detect the voltage level of the CP signal. A method for accurately and efficiently detecting the voltage level of the CP signal is needed.

[0005] Meanwhile, the construction of charging infrastructure, such as EVSEs, requires significant time, space, and cost. Furthermore, charging EVs on EVSEs takes considerable time, making commercialization of EVs difficult. To address these issues, technologies supporting vehicle-to-vehicle (V2V) charging are needed.

[0006] The technical problem to be solved by the present invention is to provide a charging device for charging an electric vehicle (EV).

[0007] According to one embodiment of the present invention, a charging device for an electric vehicle includes a supply module for a first mode that transmits a first PWM (Pulse Wide Modulation) signal to the outside, a charging module for a second mode that receives a second PWM signal from the outside, and a control unit that controls the supply module and the charging module, wherein the charging module includes a first line that receives a connector proximity detection signal and a second line that receives a control pilot signal, and the supply module includes a signal output unit that outputs the first PWM signal, a resistor unit arranged between the signal output unit and the second line, and a leakage current blocking unit arranged between the signal output unit and the resistor unit.

[0008] The above leakage current blocking unit includes a diode and can block the flow of current in the direction from the resistance unit toward the signal output unit.

[0009] The above resistance section may include a resistance of 1 kΩ.

[0010] The above signal output unit may include a power booster IC (integration chip).

[0011] The signal output unit includes a comparator that compares a voltage value of a pulse signal generated by the control unit with a reference value, a first power supply unit connected to a first terminal of the comparator, a first switch connected to the first power supply unit, a second power supply unit connected to a second terminal of the comparator, and a second switch connected to the second power supply unit, and the first switch and the second switch can be alternately turned on according to a comparison result of the comparator.

[0012] The first power supply unit can supply power of +12V±0.6V, and the second power supply unit can supply power of -12V±0.6V.

[0013] The above leakage current blocking unit may include a first diode arranged between the first switch and the resistor unit and a second diode arranged between the second switch and the resistor unit, wherein the first diode may be arranged to conduct in a direction from the first switch toward the resistor unit, and the second diode may be arranged to conduct in a direction from the second switch toward the resistor unit.

[0014] The charging module may include a detection unit that detects at least one of a duty ratio and a voltage of the second PWM signal.

[0015] The above detection unit is connected to the supply module and can further detect at least one of the duty ratio and voltage of the first PWM signal.

[0016] The above leakage current blocking unit can block leakage of the second PWM signal to the supply module.

[0017] The above leakage current blocking unit can block leakage of the second PWM signal to the supply module in the sleep mode of the charging device.

[0018] The above control unit can operate in the first mode or the second mode.

[0019] According to embodiments of the present invention, a charging device can be provided that operates not only in a charging mode, in which an EV receives power from an external source, but also in a supply mode, in which it supplies power to other EVs. In particular, embodiments of the present invention can provide a charging device that supports both charging and supply modes without significantly increasing cost and size, and that enables accurate status detection, resulting in high reliability.

[0020] FIGS. 1 and 2 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0021] Figures 3 and 4 are examples of electrical equivalent circuits for charging between an EVSE and an EV.

[0022] Figure 5 shows a CP signal in PWM form output by EVSE.

[0023] Figures 6 and 7 are block diagrams of a charging system according to one embodiment of the present invention.

[0024] FIG. 8 is a block diagram of a charging module of a charging device in a charging system according to one embodiment of the present invention.

[0025] FIG. 9 is a charging device included in a charging system according to one embodiment of the present invention.

[0026] FIG. 10 is an example of a charging system including the charging device of FIG. 9.

[0027] Fig. 11 is an example of a charging system according to one embodiment of the present invention applied to the DIN70121 standard.

[0028] Figure 12 is a waveform of a CP signal that should be detected on the EV side in sleep mode.

[0029] Figure 13 is a waveform of a CP signal actually detected in sleep mode on the EV side that supports both V2V mode and EV mode.

[0030] FIG. 14 is a waveform of a CP signal detected in sleep mode on the EV side equipped with a charging device according to an embodiment of the present invention.

[0031] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0032] However, the technical idea of ​​the present invention is not limited to some of the embodiments described, but can be implemented in various different forms, and within the scope of the technical idea of ​​the present invention, one or more of the components between the embodiments can be selectively combined or substituted for use.

[0033] In addition, terms (including technical and scientific terms) used in the embodiments of the present invention may be interpreted as having a meaning that can be generally understood by a person of ordinary skill in the technical field to which the present invention belongs, unless explicitly and specifically defined and described, and terms that are commonly used, such as terms defined in a dictionary, may be interpreted in consideration of the contextual meaning of the relevant technology.

[0034] Additionally, the terms used in the embodiments of the present invention are intended to describe the embodiments and are not intended to limit the present invention.

[0035] In this specification, the singular may also include the plural unless specifically stated otherwise in the phrase, and when it is described as “A and / or at least one (or more) of B, C”, it may include one or more of all combinations that can be combined with A, B, C.

[0036] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used.

[0037] These terms are intended only to distinguish one component from another, and are not intended to limit the nature, order, or sequence of the component.

[0038] And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, it may include not only cases where the component is directly connected, coupled or connected to the other component, but also cases where the component is 'connected', 'coupled' or 'connected' by another component between the component and the other component.

[0039] Additionally, when described as being formed or arranged "above or below" each component, "above" or "below" includes not only cases where the two components are in direct contact with each other, but also cases where one or more other components are formed or arranged between the two components. Furthermore, when expressed as "above" or "below", it can include the meaning of a downward direction as well as an upward direction based on one component.

[0040] Hereinafter, embodiments will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or corresponding components are given the same reference numbers, and redundant descriptions thereof will be omitted.

[0041] FIGS. 1 and 2 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0042] Referring to FIGS. 1 and 2, an electric vehicle (EV) 10 can be charged from an electric vehicle supply equipment (EVSE) 20. In this specification, an EV (10) refers to a vehicle propelled by an electric motor that draws current from a rechargeable storage battery or other portable energy storage device. Although this specification focuses on an EV (10), it is self-evident that the description can also be applied to a plug-in hybrid electric road vehicle (PHEV).

[0043] For this purpose, a charging cable (22) connected to the EVSE (20) can be connected to the inlet of the EV (10). Here, the EVSE (20) is a facility that supplies AC or DC, and can be placed at a charging station, placed in a home, or implemented to be portable. The EVSE (20) can be used interchangeably with a charging station (supply), an AC charging station (AC supply), a DC charging station (DC supply), a socket-outlet, etc.

[0044] A charging device (Electric Vehicle Charging Controller, EVCC, 100) is mounted within the EV (10) and connected to the EV (10). For example, the charging device (100) may be installed within the trunk of the EV (10), but is not limited thereto.

[0045] Here, the charging device (100) can communicate with the EV (10) and EVSE (20), respectively.

[0046] The method of connecting the EV (10) to the EVSE (20) can be divided into four modes and three cases. Mode 1 is to connect the EV (10) to the AC supply network using a cable and a plug, which is connected to a standard socket outlet. Mode 2 is to connect the EV (10) to the AC supply network using a cable and a plug connected to a standard socket outlet, which has a protection system and CP function to prevent electric shock between the EV and the socket outlet. Mode 3 is to connect the EV (10) using an EVSE (20) permanently connected to the AC supply network, and the CP function is extended to control the devices within the EVSE (20). Mode 4 is to connect the EV (10) to the AC or DC supply network using a dc EVSE or a dc EV charging station using the CP function. Case A is to connect the EV (10) to the AC supply using a cable and plug assembly permanently attached to the EV. Case B connects the EV (10) to the supply using a detachable cable assembly at both ends. Case C connects the EV (10) to the supply using a supply cable and vehicle connector permanently attached to the EV charging station.

[0047] A cable assembly between an EV (10) and an EVSE (20) may be provided with a CP conductor, which is an insulated conductor that creates a CP circuit, together with a PE (protective conductor). Here, the CP circuit is a circuit designed for signal transmission or communication between the EV (10) and the EVSE (20), and the CP function may be used to monitor and control the interaction between the EV (10) and the EVSE (20). A CPF controller (control pilot function controller), which is a device that manages the CP signal and the CP function, may be provided in the EVSE (20). The proximity function may be an electrical or mechanical means that indicates a state in which a connector is inserted into an inlet of an EV (10), or a state in which a plug is inserted into a socket outlet at a charging station.

[0048] In Mode 2, Mode 3 and Mode 4, the EVSE (20) has the function of checking continuous continuity of the protective earthing conductor, verifying that the EV (10) is properly connected to the EVSE (20), supplying power to the EV (10), cutting off power supplied to the EV (10), and transmitting maximum current information. Here, in order to supply power to the EV (10), the CP function between the EVSE (20) and the EV (10) must be accurately set to a signal state that allows power supply.

[0049] In mode 2, mode 3 and mode 4, the CP function is performed through a CP circuit using PWM (pulse wide modulation).

[0050] Figures 3 and 4 are examples of electrical equivalent circuits for charging between an EVSE and an EV.

[0051] Referring to FIGS. 3 and 4, the EVSE (20) includes an oscillator that generates an AC voltage for charging, and the EV (10) includes a resistor and a switch. Here, Va is a pilot wire voltage measured at the output terminal of the EVSE (20), Vg is an internal voltage of the oscillator, and Vb is a voltage, duty cycle, and frequency measured by the EV (10). The EVSE (20) communicates by setting the duty cycle of a PWM signal or a continuous DC voltage signal. The EVSE (20) can change the duty cycle of the PWM signal. The EV (10) responds by applying a resistive load to the positive half-wave of the CP circuit. If the EV (10) draws a current higher than the CP function (duty cycle), the EVSE (20) can open its switching device. At this time, the EVSE (20) will follow the conditions for the allowed response time of the EV (10), the current tolerance with respect to the duty cycle generated by the EVSE (20), and the tolerance of the current measurement in the EVSE (20) itself. The amount of voltage charged to the battery can be controlled by turning on and off the switch connected to the resistor on the EV (10) side.

[0052] Figure 5 shows a CP signal in PWM form output by EVSE.

[0053] Referring to Fig. 5, the EVSE (20) outputs a CP signal in the form of a PWM having a maximum voltage of +12 V and a minimum voltage of -12 V. The charging device (100) of the EV (10) detects the duty cycle and voltage size of the CP signal to monitor and control the status.

[0054] The states according to the CP signal can be divided into state A, state B, state C, state D, state E, and state F. State A means a state in which the charger is not connected between the EVSE (20) and the EV (10), that is, an unplugged state, and when the peak of the CP signal is +12 V ± 1 V, it is determined to be state A. State B means a state in which the charger is connected between the EVSE (20) and the EV (10), that is, a plugged state, and may mean a state in which charging is ready. When the maximum voltage of the CP signal is +9 V ± 1 V and the minimum voltage is -12 V ± 1 V, it is determined to be state B. State C and state D mean a state in which charging is in progress, that is, a charging state, and in particular, state D may mean a state in which ventilation is required during charging. When the maximum voltage of the CP signal is +6V±1V and the minimum voltage is -12V±1V, it is determined to be in the C state, and when the maximum voltage of the CP signal is +3V±1V and the minimum voltage is -12V±1V, it is determined to be in the D state. The E state and the F state may indicate error states. For example, the E state may indicate a state in which power is not supplied to the EVSE (20), and the F state may indicate a state in which the EVSE (20) is unavailable. When the maximum voltage of the CP signal is +0V±1V and the minimum voltage is -12V±1V, it is determined to be in the E state, and when the maximum voltage of the CP signal is -12V±1V and the minimum voltage is -12V±1V, it is determined to be in the F state.

[0055] Meanwhile, sleep mode is a mode for energy saving, and the EV (10) and EVSE (20) can enter sleep mode after negotiating a pause through the HLC protocol. On the EVSE (20) side, sleep mode means that the oscillator is turned off, the +12 V supply of the pilot line is maintained, and the power of the lower layer communication module is turned off. On the EV (10) side, sleep mode means the B state, and the power of the lower layer communication module can be turned off. The wake-up mechanism may also be used after the charging session has already ended so that the counterpart station can reset the HLC.

[0056] Interaction between the EVSE (20) and the EV (10) can be monitored and controlled through the CP signal, and as described above, the voltage level of the CP signal can vary depending on the charging state. Accordingly, the charging device (100) of the EV (10) must accurately detect the voltage level of the CP signal.

[0057] In general, the charging device (100) can detect the positive voltage, which is the maximum voltage, and the negative voltage, which is the minimum voltage, of the CP signal, and determine the charging state between the EVSE (20) and the EV (10) based on the detected maximum and minimum voltages. According to an embodiment of the present invention, the charging device (100) aims to efficiently monitor the charging state between the EVSE (20) and the EV (10) based on the CP signal.

[0058] FIGS. 6 and 7 are block diagrams of a charging system according to one embodiment of the present invention, and FIG. 8 is a block diagram of a charging module of a charging device in a charging system according to one embodiment of the present invention.

[0059] Referring to FIGS. 6 and 7, the first EV (600) may be connected to an EVSE (700) or may be connected to a second EV (800), which is another EV. The first EV (600) may operate in a first mode for supplying power to an external source, or in a second mode for receiving power from an external source. For example, the first EV (600) may be connected to an EVSE (700) and may operate in a second mode for receiving power from the EVSE (700). Alternatively, the first EV (600) may be connected to a second EV (800) and may operate in a first mode for supplying power to the second EV (800), or in a second mode for receiving power from the second EV (800).

[0060] In this specification, the first mode, which supplies power externally, may be used interchangeably with the V2V (Vehicle to Vehicle) mode or the supply mode. Furthermore, the second mode, which receives power externally, may be used interchangeably with the EV mode or the charging mode.

[0061] Each of the first EV (600) and the second EV (800) is equipped with a charging device (100). Typically, the charging device (100) is initially set to operate in the second mode, and can be changed to operate in the first mode by a user setting or control unit. To this end, the charging device (100) must include a module supporting the EVSE (20) function along with a module supporting the EV (10) function of FIGS. 3 and 4.

[0062] According to an embodiment of the present invention, a charging device (100) includes a connection unit (110), a supply module (120), a charging module (130), and a control unit (140). Since the embodiment of the present invention relates to a method and device for detecting a CP signal, for convenience of explanation, the description will focus on CP signal detection of the charging device (100). Except for the content regarding CP signal detection, known technologies regarding the charging device (100) can be applied to other content.

[0063] The control unit (140) controls the connection unit (110), the supply module (120), and the charging module (130), and generates a control signal for charging between the first EV (600), the EVSE (700), and the second EV (800). The control signal for charging generated by the control unit (140) may be transmitted to the EVSE (700) or the second EV (800) through the connection unit (110), or may be transmitted to the ECU (610) in the first EV (600).

[0064] The connection unit (110) is connected to the EVSE (700) or the second EV (800) and transmits signals between the control unit (140) and the EVSE (700) or the second EV (800). For example, the connection unit (110) may transmit a charging-related signal received from the EVSE (700) or the second EV (800) to the control unit (140), and transmit a control signal for charging generated by the control unit (140) to the EVSE (700) or the second EV (800). In addition, the connection unit (110) may transmit power received from the EVSE (700) or the second EV (800) to the battery (620) in the first EV (600) according to the control signal for charging generated by the control unit (140). Alternatively, the connecting portion (110) may transmit power to the second EV (800) according to a control signal for charging generated by the control portion (140).

[0065] Meanwhile, the supply module (120) supports a first mode for supplying power to the outside, i.e., V2V (Vehicle to Vehicle) mode or supply mode. To this end, the supply module (120) includes at least a part of the functions of the EVSE (20) shown in FIGS. 3 and 4. That is, the supply module (120) generates a first PWM (Pulse Wide Modulation) signal and transmits the first PWM signal to the second EV (800). The charging module (130) supports a second mode for supplying power from the outside, i.e., EV mode or charging mode. That is, the charging module (130) receives a second PWM (Pulse Wide Modulation) signal from the EVSE (700) or the second EV (800).

[0066] The supply module (120) and the charging module (130) can be selectively driven. For example, when the charging device (100) operates in a first mode in which it supplies power to the outside, the supply module (120) can be activated, and when the charging device (100) operates in a second mode in which it receives power from the outside, the charging module (130) can be activated. When the supply module (120) is activated, at least some functions of the charging module (130) can be deactivated, and when the charging module (130) is activated, at least some functions of the supply module (120) can be deactivated. For example, when the charging module (130) is activated, the first PWM signal generation function of the supply module (120) can be turned off. For example, if the charging module (130) is initially set to be activated and the charging device (100) wishes to operate in the first mode, at least some functions of the charging module (130) may be deactivated and the supply module (120) may be activated by user settings or control of the control unit (140). For example, if the charging module (130) is initially set to be activated and the charging device (100) wishes to operate in the first mode, the supply module (120) may additionally be activated by user settings or control of the control unit (140).

[0067] Meanwhile, when the charging device (100) operates in the second mode, the connection unit (110) receives a CP (Control Pilot) signal in the form of PWM (Pulse Wide Modulation) from the EVSE (700) or the second EV (800). Here, the CP signal is a signal in the form of PWM having a predetermined duty cycle, and may be in the form exemplified in FIG. 5. The CP signal is a signal for monitoring and controlling the interaction between the first EV (600) and the EVSE (700) or the interaction between the first EV (600) and the second EV (800). The charging device (100) detects the duty cycle, positive voltage, and negative voltage of the CP signal in the form of PWM received from the EVSE (700) or the second EV (800), and can monitor the charging status and control charging based on these.

[0068] Referring to FIG. 8, the charging module (130) includes a duty detection unit (131) for detecting the duty of the CP signal, a positive voltage detection unit (132) for detecting the positive voltage of the CP signal, and a negative voltage detection unit (133) for detecting the negative voltage of the CP signal. The duty detection unit (131), the positive voltage detection unit (132), and the negative voltage detection unit (133) are connected to the control unit (140) and can transmit a detection value to the control unit (140). Here, the positive voltage may be the maximum voltage of the CP signal in the form of PWM, i.e., the positive voltage peak, and the negative voltage may be the minimum voltage of the CP signal in the form of PWM, i.e., the negative voltage peak. The duty detection unit (131), the positive voltage detection unit (132), and the negative voltage detection unit (133) may be implemented by a monitoring resistor (Rm) and a monitoring capacitor (Cm) on the EV (10) side, as illustrated in FIG. 4.

[0069] FIG. 9 is a charging device included in a charging system according to one embodiment of the present invention, and FIG. 10 is an example of a charging system including the charging device of FIG. 9.

[0070] Referring to FIGS. 9 and 10, a charging system according to one embodiment of the present invention includes a charging device (100). The charging device (100) can be mounted on an EV. When the charging device (100) is mounted on a first EV (600) of FIGS. 6 and 7, the charging device (100) can be connected to an EVSE (700) or a second EV (800) of FIGS. 6 and 7. Although the charging device (100) is illustrated as being connected to the EVSE (700) in FIG. 10, it is not limited thereto and can also be connected to the second EV (800). That is, the charging device (100) can be connected to the EVSE (700) and operate in a second mode in which it receives power from the EVSE (700). Alternatively, the charging device (100) can be connected to the second EV (800) and operate in a second mode in which it receives power from the second EV (800). Alternatively, the charging device (100) may be connected to the second EV (800) and may operate in a first mode to supply power to the second EV (800).

[0071] To this end, the charging device (100) includes a supply module (120) for a first mode that transmits a first PWM signal to the outside and a charging module (130) for a second mode that receives a second PWM signal from the outside. The charging module (130) includes a PD (proximity detection) line that receives a connector proximity detection signal and a CP (control pilot) line that receives a control pilot signal. In addition, the charging module (130) includes a duty detection unit (131) that detects a duty of a CP signal, a positive voltage detection unit (132) that detects a positive voltage of the CP signal, and a negative voltage detection unit (133) that detects a negative voltage of the CP signal.

[0072] The duty detection unit (131), positive voltage detection unit (132), and negative voltage detection unit (133) of the charging module (130) detect the duty, positive voltage, and negative voltage of the CP signal in the form of PWM received from the outside, i.e., the second PWM signal, and accordingly, the charging status between the EVSE (700) or the second EV (800) that supplies power to the charging device (100) and the first EV (600) can be monitored.

[0073] In addition, the duty detection unit (131), positive voltage detection unit (132), and negative voltage detection unit (133) of the charging module (130) detect the duty, positive voltage, and negative voltage of the CP signal in the form of PWM transmitted to the outside by the supply module (120), i.e., the first PWM signal, and accordingly, when supplying power to the second EV (800), the DTC (diagnostic trouble code) of the charging device (100) in the first EV (600) can be monitored.

[0074] For this purpose, the supply module (120) can be connected to the CP line of the charging module (130).

[0075] According to an embodiment of the present invention, the supply module (120) includes a signal output unit (121) that outputs a first PWM signal and a resistor unit (122) arranged between the signal output unit (121) and the CP line of the charging module (130). The resistor unit (122) may include a resistor of 1 kΩ. One end of the resistor unit (122) may be connected to the CP line of the charging module (130), and the other end of the resistor unit (122) may be connected to the signal output unit (121) of the supply module (120).

[0076] According to an embodiment of the present invention, the signal output unit (121) of the supply module (120) is connected to the control unit (140). The signal output unit (121) may include a power booster IC (integration chip). For example, the signal output unit (121) includes an oscillator (not shown), a comparator (121A), a +12 V power supply, a -12 V power supply, a first switch (S1) and a second switch (S2). Here, the first switch (S1) and the second switch (S2) may be transistors. Here, the first switch (S1) and the second switch (S2) may be FETs (field effect transistors). The control unit (140) is connected to the oscillator and controls the generation of a PWM signal. For example, the control unit (140) may control the oscillator to generate a PWM signal having a duty of 50% and an amplitude of 3 V. The comparator (121A) is connected to the oscillator and can compare the voltage value of the PWM signal generated by the oscillator with a reference value. In addition, the +12V power supply can be connected to the first terminal of the comparator (121A), and the -12V power supply can be connected to the second terminal of the comparator (121A). Here, the +12V power supply may be a power supply that supplies a voltage of +12V±0.6V, and the -12V power supply may be a power supply that supplies a voltage of -12V±0.6V. Meanwhile, as described above, both ends of the resistor unit (122) include one end connected to the CP line of the charging module (130) and the other end connected to the signal output unit (121). A first switch (S1) is arranged between the other end of the resistor unit (122) and a +12 V power supply, and a second switch (S2) is arranged between the other end of the resistor unit (122) and a -12 V power supply. The turn-on and turn-off of the first switch (S1) and the second switch (S2) are alternately controlled according to the comparison result of the comparator. Accordingly, when the charging device (100) operates in the first mode, the signal output unit (121) of the supply module (120) can output a first PWM signal of ±12 V according to the control of the control unit (140).Accordingly, the charging device (100) mounted on the first EV (600) can perform the function of an EVSE that supplies power to another vehicle.

[0077] Meanwhile, the charging device (100) according to the embodiment of the present invention operates in a first mode for transmitting a first PWM signal to the outside, or in a second mode for receiving a second PWM signal from the outside. When the charging device (100) operates in the second mode, the second PWM signal generated by the external EVSE (700) or the second EV (800) is transmitted to the charging module (130) of the charging device (100) through the CP line. When the charging device (100) according to the embodiment of the present invention supports both the first mode and the second mode, the supply module (120) may also be connected to the CP line of the charging module (130) as described above. Accordingly, a current leakage phenomenon may occur in which a part of the second PWM signal generated by the external EVSE (700) or the second EV (800) flows to the supply module (120). In the second mode, if the charging module (130) detects a CP signal with a maximum voltage of +9 V ± 1 V and a minimum voltage of -12 V ± 1 V, it is determined that the EVSE and EV are in a B state, which is a charger connection and charging preparation state. However, if a current leakage phenomenon occurs to the supply module (120), the charging module (130) may have difficulty precisely detecting the positive and negative voltages of the CP signal, and thus, accurate detection of the charging state may be difficult.

[0078] According to an embodiment of the present invention, the supply module (120) further includes a leakage current blocking unit (123) disposed between the signal output unit (121) and the resistor unit (122). The leakage current blocking unit (123) passes a first PWM signal from the signal output unit (121) toward the resistor unit (122), but prevents a part of a second PWM signal generated by an external EVSE (700) or a second EV (800) from leaking to the supply module (120).

[0079] For example, the leakage current blocking unit (123) includes a diode. The diode included in the leakage current blocking unit (123) may be arranged to allow current to pass in a direction from the signal output unit (121) toward the resistor unit (122), but block the flow of current in a direction from the resistor unit (122) toward the signal output unit (121).

[0080] For example, the leakage current blocking unit (123) includes a first diode (D1) and a second diode (D2). The first diode (D1) may be disposed between the other end of the resistor unit (122) and the first switch (S1), and the second diode (D2) may be disposed between the other end of the resistor unit (122) and the second switch (S2). Here, the first diode (D1) may be disposed so as to conduct in a direction from the first switch (S1) toward the resistor unit (122), and the second diode (D2) may be disposed so as to conduct in a direction from the second switch (S2) toward the resistor unit (122). Accordingly, the flow of current in the direction from the resistor unit (122) toward the signal output unit (121) is blocked, and the charging device (100) operating in the second mode can accurately detect the CP signal.

[0081] Fig. 11 is an example of a charging system according to one embodiment of the present invention applied to the DIN70121 standard.

[0082] Referring to Fig. 11, a charging system supporting the DIN70121 standard includes an EV side (1100) and an EVSE side (1200). The EV side (1100) may be the first EV (600) of Figs. 6 and 7, and the EVSE side (1200) may be the EVSE (700) or the second EV (800) of Figs. 6 and 7. According to an embodiment of the present invention, the EV side (1100) may include a supply module (1120) and a charging module (1130). The description of the supply module (1120) and the charging module (1130) may be the same as the description of the supply module (120) and the charging module (130) described with reference to Figs. 9 and 10.

[0083] That is, the supply module (120) includes a signal generation unit (121) and a resistance unit (122) for charging another EV, and further includes a leakage current blocking unit (123) arranged between the signal generation unit (121) and the resistance unit (122).

[0084] The resistance unit (122) of the supply module (120) may be smaller than the resistances R2 and R3 of the charging module (130). For example, the resistance unit (122) of the supply module (120) may include a resistance of 1 kΩ. Although not shown, the supply module (120) includes a PMIC (Power Management Integrated Circuit), and voltages of +12 V and -12 V may be applied to a pulse signal generated by an oscillator by the PMIC. Accordingly, the EV may perform the same function as the EVSE.

[0085] Meanwhile, the EV side (1100) and the EVSE side (1200) may each further include a communication unit. The communication unit may be, for example, a PLC communication unit and may support CAN communication, which is a vehicle communication protocol. The PLC communication unit may be connected to both ends of the capacitor (Cv). Accordingly, the PLC communication unit may be connected not only to the charging module (130) but also to the supply module (120), and the supply module (120) and the charging module (130) may share the PLC communication unit.

[0086] FIG. 12 is a waveform of a CP signal to be detected on the EV side in sleep mode, FIG. 13 is a waveform of a CP signal actually detected on the EV side supporting both V2V mode and EV mode in sleep mode, and FIG. 14 is a waveform of a CP signal detected on the EV side equipped with a charging device according to an embodiment of the present invention in sleep mode.

[0087] Referring to Fig. 12, the normal waveform of the CP signal to be detected on the EV side in sleep mode is a PWM signal with a minimum voltage of -12 V and a maximum voltage of +9 V.

[0088] However, referring to Fig. 13, when both V2V mode and EV mode are supported, the CP signal actually detected on the EV side in sleep mode has a minimum voltage of approximately -9.5 V and a maximum voltage of approximately +6.5 V due to current leakage. Accordingly, accurate detection of the state of charge may be difficult.

[0089] Referring to FIG. 14, a charging device according to an embodiment of the present invention can prevent current leakage. Accordingly, it can be seen that the waveform of the CP signal detected in sleep mode on the EV side is close to a normal waveform, with a minimum voltage of -12 V and a maximum voltage of +8.5 V.

[0090] In this way, according to an embodiment of the present invention, leakage current from a charging device supporting both V2V mode and EV mode to a supply module supporting V2V mode is prevented, thereby enabling accurate detection of a charging state.

[0091] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

[0092] [Explanation of symbols]

[0093] 10: Electric cars

[0094] 20: Electric vehicle charging facilities

[0095] 22: Charging cable

[0096] 100: Charging device

[0097] 110: Connector

[0098] 120: Supply module

[0099] 130: Charging module

[0100] 140: Control Unit

Claims

1. In a charging device for an electric vehicle, A supply module for the first mode that transmits the first PWM (Pulse Wide Modulation) signal to the outside, A charging module for a second mode that receives a second PWM signal from the outside, and It includes a control unit that controls the supply module and the charging module, The charging module includes a first line for receiving a connector proximity detection signal and a second line for receiving a control pilot signal, A charging device in which the supply module includes a signal output unit that outputs the first PWM signal, a resistor unit arranged between the signal output unit and the second line, and a leakage current blocking unit arranged between the signal output unit and the resistor unit.

2. In paragraph 1, A charging device in which the leakage current blocking unit includes a diode and blocks the flow of current from the resistance unit toward the signal output unit.

3. In paragraph 1, The above resistance part is a charging device including a resistance of 1 kΩ.

4. In paragraph 1, The above signal output unit is a charging device including a power booster IC (integration chip).

5. In paragraph 1, The signal output unit includes a comparator that compares the voltage value of the pulse signal generated by the control unit with a reference value, a first power supply unit connected to a first terminal of the comparator, a first switch connected to the first power supply unit, a second power supply unit connected to a second terminal of the comparator, and a second switch connected to the second power supply unit. A charging device in which the first switch and the second switch are turned on alternately according to the comparison result of the comparator.

6. In paragraph 5, A charging device in which the first power supply unit supplies power of +12V±0.6V, and the second power supply unit supplies power of -12V±0.6V.

7. In paragraph 5, The above leakage current blocking unit includes a first diode arranged between the first switch and the resistor unit and a second diode arranged between the second switch and the resistor unit, A charging device wherein the first diode is arranged to conduct in a direction from the first switch toward the resistor, and the second diode is arranged to conduct in a direction from the second switch toward the resistor.

8. In paragraph 1, A charging device wherein the charging module includes a detection unit that detects at least one of a duty ratio and a voltage of the second PWM signal.

9. In paragraph 8, A charging device wherein the detection unit is connected to the supply module and further detects at least one of the duty ratio and voltage of the first PWM signal.

10. In paragraph 1, The above leakage current blocking unit is a charging device that blocks leakage of the second PWM signal to the supply module.

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