Electric vehicle charging controller and charging control method thereof

Abstract

An electric vehicle charging controller (EVCC) according to an embodiment of the present invention comprises: a charge sequence signal 1 (CSS1) detection unit for sensing a first charging sequence signal received from electric vehicle supply equipment (EVSE) via a CSS1 line; a CSS2 detection unit for sensing a second charging sequence signal received from the EVSE via a CSS2 line; a negative voltage detection unit for detecting a negative voltage of a connector proximity detection line; and a control unit for determining that a protective earth (PE) between the EVSE and the electric vehicle charging controller is open when a voltage value detected by the negative voltage detection unit is within a prescribed value.

Description

Electric vehicle charging controller and charging control method thereof

[0001] The present invention relates to an electric vehicle, and more particularly, to a charging controller for an electric vehicle and a charging control method thereof.

[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 electric vehicle, the EV and EVSE communicate via a charging connector. Once the charging connector is connected, charging begins after signaling is performed between the EVSE and EV.

[0004] Meanwhile, high voltage current flows between the EVSE and the EV, and when an emergency shutdown is required, a stopping message corresponding to the shutdown reason can be transmitted from the EV to the EVSE.

[0005] If the PE (Protective Earth) line, the grounding wire between the EVSE and the EV, is open, an emergency shutdown is required for safety reasons. Therefore, technology is needed to quickly and accurately detect PE open circuits.

[0006] The technical problem to be achieved by the present invention is to provide an electric vehicle charging controller and a charging control method thereof for quickly and accurately detecting PE (protective earth) open.

[0007] An electric vehicle charging controller (EVCC) according to one embodiment of the present invention includes a CSS1 detection unit for detecting a first charging sequence signal received from an Electric Vehicle Supply Equipment (EVSE) through a CSS1 (charge sequence signal 1) line, a CSS2 detection unit for detecting a second charging sequence signal received from the EVSE through a CSS2 (charge sequence signal 2) line, a negative voltage detection unit for detecting a negative voltage of a connector proximity detection line, and a control unit for determining that a PE (protective earth) between the EVSE and the electric vehicle charging controller is open when a voltage value detected by the negative voltage detection unit is within a predetermined value.

[0008] The above control unit can estimate the negative voltage of the voltage value detected by the negative voltage detection unit using a pre-stored voltage matching table.

[0009] The negative voltage detection unit includes a back-to-back FET (back to back field effect transistor) connected to the connector proximity detection line and a negative voltage monitoring circuit, and the negative voltage monitoring circuit may include a voltage distribution resistor and an OP Amp (operational amplifier).

[0010] The voltage distribution resistor unit includes a first resistor and a second resistor, one end of the first resistor is connected to the connector proximity detection line, and the other end of the first resistor can be connected to one end of the second resistor and the OP Amp.

[0011] The above first resistance may be 100 kΩ or more.

[0012] The present invention further includes a proximity signal detection unit that is connected to the connector proximity detection line and detects a connector proximity signal of the EVSE, and the proximity signal detection unit may include a voltage distribution resistor and an OP Amp (operational amplifier).

[0013] The CSS1 detection unit includes a voltage distribution resistor and an operational amplifier (OP Amp), and the control unit can determine whether the first charging sequence signal is received based on the voltage value detected by the CCS1 detection unit.

[0014] The voltage distribution resistor unit includes a first resistor and a second resistor, one end of the first resistor is connected to the CSS1 line, the other end of the first resistor is connected to one end of the second resistor and the OP Amp, and the first resistor may be 100 kΩ or more.

[0015] The above CCS2 detection unit includes a voltage distribution resistor and an operational amplifier (OP Amp), and the control unit can determine whether a second charging sequence signal is received based on a voltage value detected by the CCS2 detection unit.

[0016] The voltage distribution resistor unit includes a first resistor and a second resistor, one end of the first resistor is connected to the CSS2 line, the other end of the first resistor is connected to one end of the second resistor and the OP Amp, and the first resistor may be 100 kΩ or more.

[0017] A charging control method of an electric vehicle charging controller according to one embodiment of the present invention includes the steps of detecting a first charging sequence signal received from an electric vehicle supply equipment (EVSE) through a CSS1 (charge sequence signal 1) line, detecting a second charging sequence signal received from the EVSE through a CSS2 (charge sequence signal 2) line, detecting a voltage of a connector proximity detection line, and determining that a PE (protective earth) between the EVSE and the electric vehicle charging controller is open when the voltage value detected from the connector proximity detection line is within a predetermined value.

[0018] The step of determining that the above PE is open may include a step of estimating a negative voltage of a voltage value detected in the connector proximity detection line using a pre-stored voltage matching table.

[0019] According to an embodiment of the present invention, an electric vehicle charging controller can be provided that quickly and accurately detects a PE (protective earth) open between an EVSE and an EV. According to an embodiment of the present invention, while reducing costs by replacing expensive components with inexpensive components, it is possible to quickly and accurately detect a PE open between an EVSE and an EV.

[0020] Figures 1 to 3 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0021] FIG. 4 is an example of a pinout of a connection part included in an EVCC according to an embodiment of the present invention.

[0022] Figure 5 is an example of a charging interface between an EVSE and an EV.

[0023] FIGS. 6 and 7 are equivalent circuit diagrams of a charging interface between an EVSE and an EVCC according to one embodiment of the present invention.

[0024] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the attached drawings.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] Additionally, in describing components of embodiments of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] Figures 1 to 3 are drawings showing a charging system for an electric vehicle according to one embodiment of the present invention.

[0035] Referring to FIGS. 1 to 3, an electric vehicle (EV) 10 can be charged from an electric vehicle supply equipment (EVSE) 20. For this purpose, a charging cable (22) connected to the EVSE (20) can be connected to an inlet of the EV (10). Here, the EVSE (20) is a device that supplies AC or DC, and can be placed at a charging station, placed at 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.

[0036] An electric vehicle charging controller (EVCC, 100) is mounted within an EV (10) and connected to the EV (10). For example, the EVCC (100) may be installed within the trunk of the EV (10), but is not limited thereto.

[0037] Here, EVCC (100) can communicate with EV (10) and EVSE (20), respectively.

[0038] According to an embodiment of the present invention, EVCC (100) includes a control unit (110), a connection unit (120), and a detection unit (130).

[0039] The control unit (110) generates a control signal for charging between the EV (10) and the EVSE (20). The control signal for charging generated by the control unit (110) can be transmitted to the EVSE (20) through the connection unit (120) or to the ECU (12) in the EV (10).

[0040] The connection unit (120) is connected to the EVSE (20) and transmits signals between the control unit (110) and the EVSE (20). For example, the connection unit (120) may transmit a charging-related signal received from the EVSE (20) to the control unit (110) and transmit a control signal for charging generated by the control unit (110) to the EVSE (20). In addition, the connection unit (120) transmits power received from the EVSE (20) to the battery (14) in the EV (10) according to the control signal for charging generated by the control unit (110).

[0041] The detection unit (130) detects a charging-related signal between the EV (10) and the EVSE (20). The detection unit (130) is connected to the connection unit (120) and the control unit (110), respectively, and can transmit a value detected from the connection unit (120) to the control unit (110).

[0042] FIG. 4 is an example of a pinout of a connection part included in an EVCC according to an embodiment of the present invention. The pinout illustrated in FIG. 4 may be a shape shown at the end of an EV-side connector.

[0043] Referring to FIG. 4, the connection part (120) may include a total of 10 pins. For example, the connection part (120) may include an FG pin, an SS1 pin, an SS2 pin, an N / C pin, a DCP pin, a DC+ pin, a DC- pin, a PP pin, a CH pin, and a CL pin.

[0044] Here, the FG pin is a ground pin and can be a reference for the control line. The FG pin can be included in the grounding wire, i.e., PE (protective earth), between the EVSE (20) and the EVCC (100). The SS1 pin and the SS2 pin are pins that receive a charge sequence signal from the EVSE (20), respectively, and can provide a load current to a relay on the EV (10). The SS1 pin and the SS2 pin may be referred to as a charge start and stop 1 pin and a charge start stop 2 pin, respectively, or a charge sequence signal 1 pin and a charge sequence signal 2 pin, respectively.

[0045] The N / C pin may be a not connected pin.

[0046] The DCP pin is a pin that transmits a charging permission signal to the EVSE (20), and may be referred to as a charge permission and prohibition pin or a vehicle charge permission pin.

[0047] The DC-pin and DC+ pin may be rapid terminals that receive power from the EVSE (20).

[0048] The PP pin is a pin that receives a connector proximity detection signal from the EVSE (20) and may be referred to as a verification of connector connection pin or a connector proximity detection pin. The PP pin may be a pin for verifying the connection of a charging cable.

[0049] The CH pin and CL pin may be CAN bus that communicates with the EV bus to set operating parameters. When the PP pin confirms the connection of the charging cable, battery information of the EV (10) is transmitted to the EVSE (20) through the CH pin and CL pin, information of the EVSE (20) is transmitted to the EV (10), and compatibility checks can be performed between the EV (10) and the EVSE (20).

[0050] Meanwhile, the end of the EVSE (20) side connector may also have a shape corresponding to the end of the EV (10) side connector.

[0051] That is, the end of the connector on the EVSE (20) side may include a pin corresponding to the SS1 pin of FIG. 4 for transmitting a first charging sequence signal to the EV (10), a pin corresponding to the SS2 pin of FIG. 4 for transmitting a second charging sequence signal to the EV (10), a pin corresponding to the PP pin of FIG. 4 for transmitting a connector proximity detection signal to the EV (10), a pin corresponding to the DCP pin of FIG. 4 for receiving a charging permission signal from the EV (10), and a rapid terminal corresponding to the DC- pin and DC+ pin of FIG. 4 for transmitting power to the EV (10).

[0052] Additionally, the end of the EVSE (20) side connector may further include a pin corresponding to at least one of the FG pin, N / C pin, CH pin, and CL pin of FIG. 4.

[0053] As described above, the EVCC (100) can be mounted within the EV (10). Accordingly, in this specification, the EV (10) side may mean the EVCC (100).

[0054] Fig. 5 is an example of a charging interface between an EVSE and an EV. The charging interface between an EVSE and an EV may be a circuit diagram in which an end of a connector on the EV (10) side and an end of a connector on the EVSE (20) side are connected.

[0055] Referring to FIG. 5, when switch d1 is pressed on the EVSE (20) side, a first charge sequence signal is transmitted from the EVSE (20) to the EV (10) side through the SS1 line, i.e., charge sequence signal 1 (CSS 1) line, and accordingly, current flows to the EV side optocoupler f.

[0056] And, when switch d2 is pressed on the EVSE (20) side, a second charging sequence signal is transmitted from the EVSE (20) to the EV (10) through the SS2 line, i.e., the charging sequence signal 2 (CSS 2) line, and accordingly, current flows to the optocoupler g on the EV (10) side.

[0057] And, when a connector proximity detection signal of the EVSE (20) is transmitted from the EVSE (20) to the EV (10) side through the PP line, i.e., the connector proximity detection line, the EV (10) side can detect whether the connector is properly connected.

[0058] Afterwards, when charging is prepared on the EV (10) side and the transistor k is pressed, the ground is connected and a current path is formed, and a charging permission signal is transmitted to the EVSE (20) through the DCP line, i.e., the vehicle charge permission line, and accordingly, current flows to the optocoupler j on the EVSE (20) side.

[0059] When the first charging sequence signal transmission from the EVSE (20) to the EV (10) side, the second charging sequence signal transmission from the EVSE (20) to the EV (10) side, the connector proximity detection signal transmission from the EVSE (20) to the EV (10) side, and the charging permission signal transmission from the EV (10) side to the EVSE (20) are completed, the battery relay on the EV (10) side is turned ON so that charging can begin.

[0060] The order of transmitting the first charging sequence signal from the EVSE (20) to the EV (10), transmitting the second charging sequence signal from the EVSE (20) to the EV (10), transmitting the connector proximity detection signal from the EVSE (20) to the EV (10), and transmitting the charging permission signal from the EV (10) side to the EVSE (20) is not limited thereto. For example, the order of transmitting the first charging sequence signal from the EVSE (20) to the EV (10), transmitting the connector proximity detection signal from the EVSE (20) to the EV (10), transmitting the charging permission signal from the EV (10) side to the EVSE (20), and transmitting the second charging sequence signal from the EVSE (20) to the EV (10) may be carried out.

[0061] The requirements for each EVSE component in the circuit diagram shown in Fig. 5 are as shown in Table 1.

[0062] TerminalItemMinimum valueTypical valueMaximum valueUnitCharge sequence signal 1Charger DC12V10.812.013.2VConnector proximity detectionResistor R1190200210ΩVehicle charge permissionResistor R295010001050ΩCharge sequence signal 1Relay d1 load current22000mACharge sequence signal 2Relay d2 load current22000mA

[0063] The requirements for each EV-side component in the circuit diagram shown in Fig. 5 are as shown in Table 2.

[0064] TerminalItemMinimum valueTypical valueMaximum valueUnitCharge sequence signal 1Load current(when d1 ON)102000mACharge sequence signal 2Load current(when d1 an d2 ON)102000mAConnector proximity detectionResistor R395010001050ΩOn-board DC 12V81216VVehicle charge permissionResistor R4190200210ΩVehicle charge permissionLoad current (leakage current) between ab when switch k OFF2mAVce(collector-emitter voltage of transistor "k") at collector current=10mA0.5V

[0065] Meanwhile, according to an embodiment of the present invention, the detection unit (130) detects a PE (protective earth) open between the EV (10) and the EVSE (20). Here, PE refers to a grounding wire between the EVCC (100) and the EVSE (20), and PE open refers to a state in which the grounding wire between the EVCC (100) and the EVSE (20) is disconnected. In this specification, PE open may also be referred to as a broken PE.

[0066] In the charging interface between the EVSE (20) and the EVCC (100) illustrated in Fig. 5, if the grounding wire is disconnected, i.e., if a PE open occurs, the connector proximity detection line, i.e., the PP line, is connected to the on-board control power line, so that a closed circuit is formed between the PP line and the DCP line, i.e., the vehicle charge permission line. In this situation, the PP line acts as a pseudo grounding wire, so that even if the original grounding wire is disconnected, the pseudo grounding wire exists, and the optocoupler f and the optocoupler g are not turned off, and the charging process continues. To prevent this problem, a false-drive preventing circuit can be applied to prevent unintended current flow during charging.

[0067] Meanwhile, in the charging interface between the EVSE (20) and the EVCC (100) illustrated in Fig. 5, a change in the output state of the optocoupler f or the optocoupler g can be used to detect a PE open. However, since the optocoupler is an expensive component, and a change in the output state of the optocoupler f or the optocoupler g does not necessarily indicate a PE open, a faster and more accurate PE open detection method is required.

[0068] In an embodiment of the present invention, a circuit diagram of a charging interface between an EVSE and an EV is changed to implement a low-cost, fast, and accurate PE open structure.

[0069] FIGS. 6 and 7 are equivalent circuit diagrams of a charging interface between an EVSE and an EVCC according to one embodiment of the present invention.

[0070] Referring to FIG. 6, the EVSE (20) and the EVCC (100) are connected by a charge sequence signal 1 (CSS 1) line, a charge sequence signal 2 (CSS 2) line, a connector proximity detection (PP) line, a vehicle charge permission (DCP) line, and a protective earth (PE) line, i.e., a ground winding line. That is, the connection portion (120) of the EVCC (100) may include a CSS1 line, a CSS2 line, a PP line, a DCP line, and a PE line.

[0071] According to an embodiment of the present invention, the detection unit (130) of the EVCC (100) includes a CSS1 detection unit (600) connected to the CSS1 line to detect a first charging sequence signal received from the EVSE (20), a CSS2 detection unit (610) connected to the CSS2 line to detect a second charging sequence signal received from the EVSE (20), a negative voltage detection unit (620) connected to the PP line to detect a negative voltage of the PP line, and a proximity signal detection unit (630) connected to the PP line to detect a connector proximity signal of the EVSE (20).

[0072] And, the control unit (120) of the EVCC (100) includes a CSS1 MCU (600M) that generates a charging control signal using the detection value of the CSS1 detection unit (600), a CSS2 MCU (610M) that generates a charging control signal using the detection value of the CSS2 detection unit (610), a PE open MCU (620M) that generates a charging control signal for PE open using the detection value of the negative voltage detection unit (620), and a PP MCU (630M) that generates a charging control signal using the detection value of the proximity signal detection unit (630). Although the CSS1 MCU (600M), CSS2 MCU (610M), PE open MCU (620M), and PP MCU (630M) are illustrated as being independent MCUs, they are not limited thereto, and the CSS1 MCU (600M), CSS2 MCU (610M), PE open MCU (620M), and PP MCU (630M) may be implemented as a single integrated MCU.

[0073] The PE open MCU (620M) is connected to the negative voltage detection unit (620), and when the voltage value detected by the negative voltage detection unit (620) is within a predetermined value, it is determined that the PE (protective earth) between the EVSE (20) and the EVCC (100) is open.

[0074] More specifically, as illustrated in FIG. 5, in a normal state where PE is not open, a closed circuit is formed between the grounding wire and the DCP line, and the voltage value applied to the PP line becomes 0 V. However, in a state where PE is open, a negative voltage is applied to the PP line. Accordingly, in an embodiment of the present invention, the PE open is detected using the voltage value applied to the PP line.

[0075] According to an embodiment of the present invention, a negative voltage detection unit (620) includes a dual FET (622) connected to a PP line and a negative voltage monitoring circuit (624). Here, the false-drive preventing circuit of FIG. 5 may be omitted due to the dual FET. The dual FET (622) may include two FETs (Q4, Q5) connected back to back. Accordingly, in the present specification, the dual FET (622) may also be referred to as a back-to-back FET. The back-to-back FET is arranged between the first node (N1) of the PP line and the onboard DC 12 V. The back-to-back FET is a system in which two FETs (Q4, Q5) are connected in series with each other, but their body diodes are connected in opposite directions to block bidirectional current flow. When back-to-back FETs are placed between the first node (N1) of the PP line and the onboard DC 12 V, current flow through the PP line from the EVSE (20) toward the EVCC (100) is possible, but current flow through the PP line from the EVCC (100) toward the EVSE (20) is blocked. Accordingly, formation of a closed circuit between the DCP line and the PP line can be prevented even when the PE is open.

[0076] According to an embodiment of the present invention, a negative voltage monitoring circuit (624) is connected to a first node (N1) of a PP line. The negative voltage monitoring circuit (624) may include a voltage-dividing resistor unit and an OP Amp (X4). Here, the voltage-dividing resistor unit may be disposed between the first node (N1) of the PP line and the OP Amp (X4) to distribute the voltage input to the OP Amp (X4). For example, the voltage-dividing resistor unit may include a first resistor (R3) and a second resistor (R13), one end of the first resistor (R3) may be connected to the first node (N1) of the PP line, and the other end of the first resistor (R3) may be connected to one end of the second resistor (R13) and the OP Amp (X4). At this time, the first resistor (R3) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less. In this way, if the first resistance (R3) of the voltage distribution resistor is designed to be 100 kΩ or more, a structure capable of detecting an accurate voltage value without electrically affecting the surrounding circuit can be obtained.

[0077] According to an embodiment of the present invention, the negative voltage monitoring circuit (624) may further include a diode (D3) disposed between the voltage-dividing resistor and the OP Amp (X4). The cathode of the diode (D3) may be connected to the voltage-dividing resistor, and the anode may be connected to the OP Amp (X4). Accordingly, the flow of current from the OP Amp (X4) toward the voltage-dividing resistor is blocked, and the negative voltage of the PP line may be monitored.

[0078] Meanwhile, the PE open MCU (620M) is connected to the negative voltage detection unit (620), and if the voltage value detected by the negative voltage detection unit (620) is within a predetermined value, it determines that the PE (protective earth) between the EVSE (20) and the EVCC (100) is open. To this end, the PE open MCU (620M) may store in advance a voltage matching table for estimating the negative voltage using the voltage value detected by the negative voltage detection unit (620). Table 3 is an example of a voltage matching table stored in advance by the PE open MCU (620M). For example, if the voltage value detected by the negative voltage detection unit (620) is 0.05 V, the PE open MCU (620M) estimates that the voltage value of the PP line is -1 V, if the voltage value detected by the negative voltage detection unit (620) is 0.92 V, the PE open MCU (620M) estimates that the voltage value of the PP line is -5 V, and if the voltage value detected by the negative voltage detection unit (620) is 1.83 V, the PE open MCU (620M) can estimate that the voltage value of the PP line is -8.8 V. In addition, if the voltage value detected by the negative voltage detection unit (620) is 0.68 V to 3.08 V, the PE open MCU (620M) can determine that a significant negative voltage is applied to the PP line and determine that PE is in an open state.

[0079] PP Line Voltage Value (V) Detected Voltage Value (V) PE Open Detection Range 00-10.05-20.24-30.46-40.68 PE Open Detection -50.92-61.16-71.4-81.64-8.81.83-91.88-102.12-112.35-122.6-132.85-143.08-153.32-163.51

[0080] As in the embodiment of the present invention, when PE open is detected using a negative voltage applied to the PP line, faster and more accurate PE open detection is possible compared to when PE open is detected using the change in the output state of the optocoupler f and the optocoupler g of FIG. 5.

[0081] In a case where a negative voltage detection unit (620) is arranged on the PP line as in an embodiment of the present invention, the optocoupler f and the optocoupler g of FIG. 5 can be replaced with cheaper elements. That is, according to an embodiment of the present invention, the CSS1 detection unit (600) detects the voltage value of the CSS1 line, and the CSS2 detection unit (610) detects the voltage value of the CSS2 line. To this end, the CSS1 detection unit (600) may include a voltage-dividing resistor unit and an OP Amp (X1), and the CSS2 detection unit (610) may include a voltage-dividing resistor unit and an OP Amp (X2).

[0082] The CSS1 MCU (600M) estimates the voltage value of the CSS1 line using the result value of the CSS1 detection unit (600) and detects the first charging sequence signal, and the CSS2 MCU (610M) estimates the voltage value of the CSS2 line using the result value of the CSS2 detection unit (610) and can detect the second charging sequence signal. When the first charging sequence signal and the second charging sequence signal are detected, the control unit (110) can proceed with the next procedure for charging, that is, the procedure of detecting a connector proximity detection signal from the EVSE (20) and transmitting a charging permission signal to the EVSE (20).

[0083] In this way, when PE open is detected using negative voltage detection of the PP line, the optocoupler in the CSS1 line and CSS2 line can be replaced with an OP Amp, thereby significantly reducing production costs.

[0084] At this time, the CSS1 detection unit (600) may include a voltage distribution resistor unit and an OP Amp (X1). Here, the voltage distribution resistor unit may be arranged between the second node (N2) of the CSS1 line and the OP Amp (X1) to distribute the voltage entering the OP Amp (X1). For example, the voltage distribution resistor unit may include a first resistor (R111) and a second resistor (R5), one end of the first resistor (R111) may be connected to the second node (N2) of the CSS1 line, and the other end of the first resistor (R111) may be connected to one end of the second resistor (R5) and the OP Amp (X1). At this time, the first resistor (R111) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less. Likewise, the CSS2 detection unit (610) may include a voltage-dividing resistor unit and an OP Amp (X2). Here, the voltage-dividing resistor unit may be arranged between the third node (N3) of the CSS2 line and the OP Amp (X2) to distribute the voltage entering the OP Amp (X2). For example, the voltage-dividing resistor unit may include a first resistor (R8) and a second resistor (R7), one end of the first resistor (R8) may be connected to the second node (N2) of the CSS2 line, and the other end of the first resistor (R8) may be connected to one end of the second resistor (R7) and the OP Amp (X2). At this time, the first resistor (R8) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less.

[0085] If the CSS1 detection unit (600) and the CSS2 detection unit (610) each include a voltage distribution resistor, when the EVSE (20) outputs a 12 V waveform, the CSS1 detection unit (600) and the CSS2 detection unit (610) can obtain a result value lower than 12 V, for example, a result value of about 3 V, and the control unit (120) can estimate the voltage values ​​of the CSS1 line and the CSS2 line using the result values ​​of the CSS1 detection unit (600) and the CSS2 detection unit (610). In particular, when the first resistance of the voltage distribution resistor of the CSS1 detection unit (600) and the CSS2 detection unit (610) is designed to be 100 kΩ or more, even if a voltage of 16 V is applied to the input line, the CSS1 detection unit (600) and the CSS2 detection unit (610) can obtain a result value lower than 16 V, for example, a result value of about 4 V. In this way, if the CSS1 detection unit (600) and the CSS2 detection unit (610) include a voltage distribution resistor according to an embodiment of the present invention, the control unit (120) can also detect a high voltage value of the CSS1 line and the CSS2 line, for example, a voltage value of 12 V or more and 16 V or less. In particular, if the voltage distribution resistor of the CSS1 detection unit (600) and the CSS2 detection unit (610) according to an embodiment of the present invention includes a high first resistor of 100 kΩ or more, the electrical influence of the CSS1 detection unit (600) and the CSS2 detection unit (610) on the PP line can be minimized, and thus the accuracy of negative voltage detection of the PP line can be increased.

[0086] Meanwhile, according to an embodiment of the present invention, the proximity signal detection unit (630) may also include a voltage-dividing resistor unit and an OP Amp (X3). Here, the voltage-dividing resistor unit may be arranged between the first node (N1) of the PP line and the OP Amp (X3) to distribute the voltage entering the OP Amp (X3). For example, the voltage-dividing resistor unit may include a first resistor (R10) and a second resistor (R11), one end of the first resistor (R11) may be connected to the first node (N1) of the PP line, and the other end of the first resistor (R10) may be connected to one end of the second resistor (R11) and the OP Amp (X3). At this time, the first resistor (R11) may be 100 kΩ or more, preferably 100 kΩ or more and 1000 kΩ or less, and more preferably 100 kΩ or more and 500 kΩ or less. According to an embodiment of the present invention, if the proximity signal detection unit (630) includes a voltage distribution resistor, the control unit (120) can also detect a high voltage value of 12 V or more and 16 V or less applied to the input line. In addition, if the voltage distribution resistor of the proximity signal detection unit (630) includes a high first resistor (R11) of 100 kΩ or more, the electrical influence of the proximity signal detection unit (630) on the PP line can be minimized, and thus the accuracy of negative voltage detection of the PP line can be increased.

[0087] In this way, as illustrated in FIGS. 6 and 7, a dual FET (622), a negative voltage monitoring circuit (624), and a proximity signal detection unit (630) may be connected to the first node (N1) of the PP line. Accordingly, in a normal state, a proximity detection signal is transmitted from the EVSE (20) toward the EVCC (100) through the dual FET (622), and the proximity detection signal can be detected by the proximity signal detection unit (630). In addition, in a state where PE is open, a closed circuit between the DCP line and the PP line is prevented by the dual FET (622), and a negative voltage applied to the PP line can be detected by the negative voltage monitoring circuit (624).

[0088] 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.

[0089] [Explanation of symbols]

[0090] 10: Electric cars

[0091] 20: Electric vehicle charging facilities

[0092] 22: Charging cable

[0093] 100: Electric Vehicle Charging Controller

[0094] 110: Control unit

[0095] 120: Connection

[0096] 130: Detection unit

Claims

1. In an electric vehicle charging controller (EVCC), A CSS1 detection unit that detects a first charging sequence signal received from an EVSE (Electric Vehicle Supply Equipment) through a CSS1 (charge sequence signal 1) line. A CSS2 detection unit that detects a second charging sequence signal received from the EVSE through the CSS2 (charge sequence signal 2) line; A negative voltage detection unit that detects the negative voltage of a connector proximity detection line, A control unit that determines that the PE (protective earth) between the EVSE and the electric vehicle charging controller is open when the voltage value detected by the negative voltage detection unit is within a predetermined value. An electric vehicle charging controller comprising:

2. In paragraph 1, An electric vehicle charging controller in which the above control unit estimates the negative voltage of the voltage value detected by the negative voltage detection unit using a pre-stored voltage matching table.

3. In paragraph 1, The above negative voltage detection unit includes a back-to-back FET (back to back field effect transistor) connected to the connector proximity detection line and a negative voltage monitoring circuit, The above negative voltage monitoring circuit is an electric vehicle charging controller including a voltage distribution resistor and an OP Amp (operational amplifier).

4. In paragraph 3, An electric vehicle charging controller wherein the voltage distribution resistor includes a first resistor and a second resistor, one end of the first resistor is connected to the connector proximity detection line, and the other end of the first resistor is connected to one end of the second resistor and the OP Amp.

5. In paragraph 4, An electric vehicle charging controller wherein the first resistance is 100 kΩ or greater.

6. In paragraph 1, Further comprising a proximity signal detection unit connected to the above connector proximity detection line and detecting a connector proximity signal of the EVSE; The above proximity signal detection unit is an electric vehicle charging controller including a voltage distribution resistor unit and an operational amplifier (OP Amp).

7. In paragraph 1, The above CSS1 detection unit includes a voltage distribution resistor and an OP Amp (operational amplifier), The above control unit is an electric vehicle charging controller that determines whether the first charging sequence signal is received based on the voltage value detected by the CCS1 detection unit.

8. In paragraph 7, An electric vehicle charging controller, wherein the voltage distribution resistor includes a first resistor and a second resistor, one end of the first resistor is connected to the CSS1 line, the other end of the first resistor is connected to one end of the second resistor and the OP Amp, and the first resistor is 100 kΩ or greater.

9. In paragraph 1, The above CCS2 detection unit includes a voltage distribution resistor and an OP Amp (operational amplifier), The above control unit is an electric vehicle charging controller that determines whether a second charging sequence signal is received based on the voltage value detected by the CCS2 detection unit.

10. In paragraph 8, An electric vehicle charging controller, wherein the voltage distribution resistor includes a first resistor and a second resistor, one end of the first resistor is connected to the CSS2 line, the other end of the first resistor is connected to one end of the second resistor and the OP Amp, and the first resistor is 100 kΩ or greater.

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