Charging system for a vehicle and battery charging stop method thereof

Abstract

The present invention relates to a charging system for a vehicle and a battery charge stop method thereof. A charging system for a vehicle and a battery charge stop method thereof can provide a method that, when a current sensor applied to a three-phase winding configured to drive a motor of a vehicle malfunctions, can stop charging of a battery, thereby preventing occurrence of torque due to operation of the motor.

Description

TECHNICAL FIELD

[0001] The present application relates to a charging system for a vehicle and a battery charge stop method thereof, and more particularly, to a charging system for a vehicle and a battery charge stop method thereof which can prevent a motor rotation operation caused by a current sensor failure when a battery is charged. BACKGROUND

[0002] A vehicle using a motor as a driving source (for example, a hybrid vehicle or an electric vehicle) has a battery installed in the vehicle to supply power to the motor.

[0003] In recent years, the battery has a gradually increasing voltage specification to shorten a charging time. However, a charging infrastructure for charging a high-end battery is not smoothly provided.

[0004] A general charging system can charge a high-end battery when an additional boost converter is applied. However, if the boost converter is added, there is a problem of an increase in size and cost of the charging system.

[0005] Therefore, the conventional charging system can boost an output of an external charger connected to the motor through an inverter of the motor, and thus charge the battery using the boosted output. Accordingly, the charging system can perform a multiple charging function of charging various specifications of the battery, and such a charging system is also called a multiple charging system.

[0006] The external charger is a charging facility outside the vehicle, and when electrically connected to the battery, the external charger can supply power used to charge the battery.

[0007] Figure 4 And Figure 5 To show a circuit diagram of the conventional charging system.

[0008] As Figure 4 shown, in the charging system, if the external charger 120 having the same output specification as the battery 110 is connected, the first relay 111, the second relay 112, and the third relay 113 are turned on and the fourth relay 114 is turned off, thereby charging the battery 110.

[0009] Further, referring to Figure 5 , in the charging system, if the external charger 120 having an output specification lower than the battery 110 is connected to the battery 110, the first relay 111, the second relay 112, and the fourth relay 114 are turned on and the third relay 113 is turned off, so that the current that has flowed through the three-phase windings 131, 132, 133 of the motor 130 and the inverter 140 charges the battery 110.

[0010] At this time, the inverter 140 operates in a boost mode through the operation of the three-phase switching modules 141, 142, and 143 to boost the output voltage of the external charger 120, and thus applies the boosted output voltage to the battery 110.

[0011] In a case where the battery 110 is charged by using the inverter 140, even when any one of the current sensors 144, 145, and 146 that detect currents flowing through the three-phase windings 131, 132, and 133 of the motor 130 fails, a current is not applied to one of the three-phase windings 131, 132, and 133, resulting in an imbalance in the currents applied to the three-phase windings 131, 132, and 133.

[0012] When the battery 110 is normally charged, the currents applied to the three-phase windings 131, 132, and 133 are balanced.

[0013] When the currents applied to the three-phase windings 131, 132, and 133 are imbalanced, the inductance values of the three-phase windings 131, 132, and 133 are changed by the magnetic flux of the permanent magnet of the motor rotor, and thus the motor 130 rotates.

[0014] When the motor 130 rotates in a case where the battery 110 is charged, a dangerous situation in which the motor 130 outputs a torque to drive the vehicle occurs.

[0015] That is, even when any one of the current sensors 144, 145, and 146 fails, a problem in which the motor 130 rotates in a case where the battery 110 is charged and the vehicle is driven by the motor torque according to the rotation of the motor 130 occurs.

[0016] In addition, if the motor 130 continuously operates when the current sensors 144, 145, and 146 fail, the motor 130 is burned.

[0017] The information included in the Background section of this disclosure is intended only to enhance understanding of the general background of the present disclosure, and should not be considered to constitute general knowledge of those skilled in the art. SUMMARY

[0018] Various aspects of the present disclosure are directed to providing a charging system for a vehicle and a battery charge stop method thereof, which can stop charging of a battery when a current sensor configured to apply a current to a three-phase winding of a motor for driving a vehicle fails, thereby preventing occurrence of a torque due to operation of the motor.

[0019] Accordingly, various aspects of the present application provide a charging system for a vehicle, the charging system including: a motor configured to drive the vehicle; a battery connected to the motor and supplying power to the motor; an inverter installed between the motor and the battery and configured to control a flow of current between the motor and the battery; and a controller connected to the inverter and configured to: control a switching duty ratio of the inverter according to a previous duty ratio command transmitted to the inverter until an abnormal current sensor occurs when charging the battery through the motor and the inverter, and then linearly decrease the switching duty ratio of the inverter to reach zero when the abnormal current sensor occurs among current sensors connected to the inverter and respectively detecting amounts of current applied to three-phase windings of the motor.

[0020] According to various exemplary embodiments of the present application, when the switching duty ratio of the inverter is controlled according to the previous duty ratio command, all switching modules of the inverter operate with the same switching duty ratio according to the previous duty ratio command.

[0021] The inverter can be configured to include: a first switching module configured to control a flow of current applied to a first winding among the three-phase windings of the motor; a second switching module configured to control a flow of current applied to a second winding among the three-phase windings; and a third switching module configured to control a flow of current applied to a third winding among the three-phase windings.

[0022] Further, according to various exemplary embodiments of the present application, the controller is configured to decrease the switching duty ratios of the first, second, and third switching modules at the same ratio when linearly decreasing the switching duty ratio of the inverter.

[0023] Further, according to various exemplary embodiments of the present application, the controller can be configured to determine whether an output current of an external charger that provides power for charging the battery becomes zero when the switching duty ratio of the inverter reaches zero, and determine that the charging of the battery is stopped when the output current of the external charger becomes zero.

[0024] Further, according to various exemplary embodiments of the present application, the controller can be configured to control the switching duty ratio of the inverter according to the previous duty ratio command for a predetermined multiple of a control period of the current applied to the motor.

[0025] Further, according to various exemplary embodiments of the present application, the controller can linearly decrease the switching duty ratio of the inverter from a real-time switching duty ratio value to 0% for a predetermined multiple of a control period of the current applied to the motor.

[0026] Further, according to various exemplary embodiments of the present application, the controller can be configured to determine that an abnormal current sensor has occurred if the rising slope of the voltage value across the winding is not identical to the rising slope of the voltage value detected by the current sensor when the switching module controlling the flow of the current applied to each winding of the three-phase winding of the motor is turned on.

[0027] Further, according to various exemplary embodiments of the present application, the controller can be configured to determine that an abnormal current sensor has occurred if the rising slope of the voltage value across the winding is not identical to the rising slope of the voltage value detected by the current sensor when the switching module controlling the flow of the current applied to each winding of the three-phase winding of the motor is turned off.

[0028] Meanwhile, various aspects of the present application are directed to a battery charge stop method for a charging system of a vehicle including a motor configured to drive the vehicle, a battery connected to the motor and supplying power to the motor, and an inverter connecting the motor and the battery, the method including determining whether an abnormal current sensor has occurred in a current sensor connected to the inverter and detecting the amount of current applied to the three-phase winding of the motor when charging the battery by the motor and the inverter, controlling the switching duty of the inverter according to a previous duty command transmitted to the inverter before the abnormal current sensor has occurred when it is determined that the abnormal current sensor has occurred in the current sensor, reaching the switching duty of the inverter to zero by linearly reducing the switching duty of the inverter, and determining that the charging of the battery is stopped when the switching duty of the inverter becomes zero.

[0029] Through the above configuration, various aspects of the present application provide the following effects.

[0030] First, by stopping the charging of the battery when the current sensor has failed, it is possible to prevent the vehicle from traveling due to the operation of the motor.

[0031] Second, it is possible to prevent dangerous situations due to the vehicle traveling while the battery is being charged.

[0032] Third, it is possible to prevent the motor from catching fire due to the continuous operation of the motor when the current sensor has failed.

[0033] It should be understood that the terms "vehicle" or "vehicular" or other similar terminology used herein generally include a motor vehicle, such as a passenger automobile including sport utility vehicles (SUV), a bus, a truck, various commercial vehicles, a boat, a ship, an aircraft, etc., and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen powered vehicles, and other alternative fuel vehicles (e.g., fuel sourced from non-fossil sources). As referred to herein, a hybrid vehicle is a vehicle having two or more sources of power, such as a vehicle having both gasoline power and electric power.

[0034] The above and other features of the present application are discussed in the following.

[0035] The method and apparatus of the present application has other features and advantages which will be apparent from or which will be elucidated with regard to the accompanying drawings and the following detailed description of a specific embodiment thereof, to be considered in conjunction with the appended claims, in which the sole figure is jointly used to explain the certain principles of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 A block diagram of a charging system according to various exemplary embodiments of the present application is shown.

[0037] Figure 2 A circuit diagram showing a state in which an external charger is connected to Figure 1 the charging system shown.

[0038] Figure 3 A flowchart showing a battery charge stop method of a charging system according to various exemplary embodiments of the present application is shown.

[0039] Figure 4 and Figure 5 A circuit diagram of a conventional charging system is shown.

[0040] It should be understood that the drawings are not to scale as the drawings are schematically simplified to illustrate various exemplary features to show the basic principles of the present application. The specific design features of the present application disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes, will be determined in part by the particular environment in which the present application is applied and used.

[0041] In these drawings, reference numerals refer to like or equivalent parts throughout the several figures of the drawings. DETAILED DESCRIPTION

[0042] Reference will now be made in detail to various embodiments of the application, examples of which are illustrated in the accompanying drawings and described below. While the application will be described in conjunction with the exemplary embodiments, it will be understood that the description is not intended to limit the application to those exemplary embodiments. On the contrary, the description is intended to cover all alternatives, modifications, equivalents and other embodiments that can be included within the spirit and scope of the application as defined by the appended claims.

[0043] Hereinafter, the present application will be described with reference to the accompanying drawings so that those skilled in the art can easily practice the present application.

[0044] Figure 1 To show a block diagram of a charging system according to various exemplary embodiments of the present application, and Figure 2 To show a circuit diagram of a state in which an external charger is connected to Figure 1 the charging system shown.

[0045] As Figure 1 and Figure 2 shown, the charging system is configured to include a motor 10, a battery 20, and an inverter 30; the motor 10 can generate a driving force for driving a vehicle; the battery 20 can supply power for driving the motor 10 to the motor 10; and the inverter 30 is disposed between the battery 20 and the motor 10, thereby electrically connecting the battery 20 and the motor 10.

[0046] When driving the motor 10, the inverter 30 can convert DC power supplied from the battery 20 to the motor 10 into AC power, thereby applying the AC power to the motor 10.

[0047] That is, the inverter 30 can convert DC power of the battery 20 into AC power for driving the motor 10, thereby supplying the AC power to the motor 10.

[0048] At this time, the switching operation of the inverter 30 can be controlled by an instruction of a controller 40 in the vehicle. The controller 40 can be a motor control unit that is installed to the vehicle in advance.

[0049] The controller 40 can control the operation of the switching elements 31a, 31b, 32a, 32b, 33a, 33b constituting the inverter 30, thereby converting DC power supplied from the battery 20 to the motor 10 into AC power used by the motor 10.

[0050] As Figure 2As illustrated, the inverter 30 can include six switching elements 31a, 31b, 32a, 32b, 33a, 33b, thereby converting the DC power into the AC power. Among the switching elements 31a, 31b, 32a, 32b, 33a, 33b, two switching elements connected in series become a phase switching module. That is, the inverter 30 can include three switching modules 31, 32, 33 connected in parallel.

[0051] The inverter 30 can be configured to include the first switching module 31, the second switching module 32, and the third switching module 33.

[0052] The first switching module 31 can be configured to intermittently control the flow of the current applied to the first winding 11 among the three-phase windings 11, 12, 13 of the motor 10. The second switching module 32 can be configured to intermittently control the flow of the current applied to the second winding 12 among the three-phase windings 11, 12, 13 of the motor 10. The third switching module 33 can be configured to intermittently control the flow of the current applied to the third winding 13 among the three-phase windings 11, 12, 13 of the motor 10.

[0053] When the battery 20 is charged by using the external charger 50 having a voltage specification lower than the output voltage of the battery 20, the inverter 30 can step up the output voltage of the external charger 50, thereby applying the stepped-up output voltage to the battery 20.

[0054] The inverter 30 can implement a step-up mode of a general step-up converter when charging the battery 20.

[0055] The output voltage of the external charger 50 can be stepped up to the output voltage of the battery 20 by the step-up control of the inverter 30. At this time, the switching operation of the inverter 30 can be controlled by the controller 40.

[0056] The external charger 50 is a power source outside the vehicle, and when the external charger is electrically connected to the battery 20, the external charger can supply the AC power used to charge the battery 20. That is, the external charger 50 can also be referred to as an external AC power source.

[0057] The inverter 30 can step up the power applied through the three-phase windings 11, 12, 13 of the motor 10, thereby applying the stepped-up power to the battery 20 when charging the battery 20.

[0058] The inverter 30 can operate in a step-up mode by the switching operation of the switching modules 31, 32, 33, thereby stepping up the AC power supplied from the external charger 50 to the voltage level of the battery 20.

[0059] At this time, the switching modules 31, 32, 33 are turned on or off according to the instructions of the controller 40.

[0060] As shown in FIG. 1, the motor 10 is a three-phase motor including three windings 11, 12, 13 connected in parallel. The three windings 11, 12, 13 are three-phase windings of a motor stator, and can be a first winding 11, a second winding 12, and a third winding 13 connected in parallel. Figure 2

[0061] The current flowing through the first winding 11 can be applied to the battery 20 through the first switching module 31, the current flowing through the second winding 12 can be applied to the battery 20 through the second switching module 32, and the current flowing through the third winding 13 can be applied to the battery 20 through the third switching module 33.

[0062] In addition, the inverter 30 can be configured to include a first current sensor 34, a second current sensor 35, and a third current sensor 36. The first current sensor 34 can detect the amount (current value) of current flowing through the first winding 11. The second current sensor 35 can detect the amount of current flowing through the second winding 12. The third current sensor 36 can detect the amount of current flowing through the third winding 13.

[0063] The signals of the current sensors 34, 35, 36 can be transmitted to the controller 40, and the controller 40 can control the switching operation of the inverter 30 based on the signals of the current sensors 34, 35, 36.

[0064] In addition, when the battery 20 is charged by using the inverter 30 and the motor 10, the first relay 21, the second relay 22, the third relay 23, and the fourth relay 24 are turned on, and the fifth relay 25 is turned off, so that the external charger 50 can supply power to the battery 20 through the motor 10 and the inverter 30.

[0065] The first relay 21 and the second relay 22 are provided to be connected to both ends of the battery 20. The third relay 23 and the fifth relay 25 can directly connect the external charger 50 to the battery 20 when turned on. The fourth relay 24 can directly connect the external charger 50 to the motor 10 when turned on together with the third relay 23. Meanwhile, if one of the current sensors 34, 35, 36 of the inverter 30 malfunctions when the battery 20 is charged, the switching module connected to the malfunctioning current sensor can be immediately turned off.

[0066] For example, when the first current sensor 34 malfunctions, the first switching module 31 can be turned off, when the second current sensor 35 malfunctions, the second switching module 32 can be turned off, and when the third current sensor 36 malfunctions, the third switching module 33 can be turned off.

[0067] ​If the first switch module 31 is turned off, the flow of the current applied to the first winding 11 can be stopped, if the second switch module 32 is turned off, the flow of the current applied to the second winding 12 can be stopped, and in addition, if the third switch module 33 is turned off, the flow of the current applied to the third winding 13 can be stopped.

[0068] As described above, when no current is applied to any one of the three windings 11, 12, 13, the amount of the current applied to the three windings 11, 12, 13 differs, resulting in an imbalance of the force acting on the rotor of the motor 10, thereby rotating the rotor.

[0069] In the case of charging the battery 20, when the rotor of the motor 10 is rotated, a motor torque is generated, and thus a problem of driving a vehicle can be caused.

[0070] If the battery 20 is normally charged, the output current of the external charger 50 is simultaneously applied to the three windings 11, 12, 13.

[0071] The controller 40 monitors whether the current sensors 34, 35, 36 are malfunctioning when the battery 20 is charged, thereby preventing the generation of the motor torque when the battery 20 is charged.

[0072] The controller 40 can determine that any one of the current sensors is malfunctioning, for example, if no signal value of any one of the current sensors is generated when the battery 20 is charged, or if a difference between the signal values of the current sensors 34, 35, 36 exceeds a predetermined error range, or if the motor 10 is driven so that the motor torque is generated.

[0073] In addition, even when the signal value of the current sensor, that is, the output voltage value, is the maximum signal value of a set normal operating range, that is, the second output voltage value, or more, or the minimum signal value, that is, the first output voltage value, or less, the controller 40 can determine that the corresponding current sensor is malfunctioning. The normal operating range can be the first output voltage value to the second output voltage value.

[0074] In addition, when the switch modules 31, 32, 33 are turned on, if the rising slope of the voltage across the inductance of the motor 10 is different from the rising slope of the signal value of the current sensor 34, 35, 36, or when the switch modules 31, 32, 33 are turned off, if the falling slope of the voltage across the inductance of the motor 10 is different from the falling slope of the signal value of the current sensor 34, 35, 36, the controller 40 can determine that the current sensor detecting the signal value of the slope different from the slope of the voltage across the inductance is malfunctioning.

[0075] When the first switch module 31 is on, if the rising slope of the voltage value across the first winding 11 is different from the rising slope of the signal value (i.e., the voltage value) detected by the first current sensor 34, the controller 40 can determine that the first current sensor 34 has failed.

[0076] When the second switch module 32 is on, if the rising slope of the voltage value across the second winding 12 is different from the rising slope of the signal value detected by the second current sensor 35, the controller 40 can determine that the second current sensor 35 has failed.

[0077] When the third switch module 33 is on, if the rising slope of the voltage value across the third winding 13 is different from the rising slope of the signal value detected by the third current sensor 36, the controller 40 can determine that the third current sensor 36 has failed.

[0078] Furthermore, when the first switch module 31 is off, if the falling slope of the voltage value across the first winding 11 is different from the falling slope of the signal value detected by the first current sensor 34, the controller 40 can determine that the first current sensor 34 has failed.

[0079] When the second switch module 32 is off, if the falling slope of the voltage value across the second winding 12 is different from the falling slope of the signal value detected by the second current sensor 35, the controller 40 can determine that the second current sensor 35 has failed.

[0080] When the third switch module 33 is off, if the falling slope of the voltage value across the third winding 13 is different from the falling slope of the signal value detected by the third current sensor 36, the controller 40 can determine that the third current sensor 36 has failed.

[0081] The voltage across the windings 11, 12, 13 can be measured by using a voltage measurement circuit.

[0082] Hereinafter, the current sensor that has failed among the three current sensors 34, 35, 36 is referred to as an "abnormal current sensor".

[0083] If it is identified that any one of the current sensors 34, 35, 36 has failed while the battery 20 is being charged, i.e., it is determined that an abnormal current sensor has occurred while the battery 20 is being charged, the controller 40 continues the duty command (i.e., the previous duty command) transmitted to the inverter 30 immediately before the abnormal current sensor occurs, thereby preventing the motor 10 from outputting a torque.

[0084] That is, if the current sensor failure is sensed while the battery 20 is being charged, the controller 40 does not change the duty command applied to the switching modules 31, 32, 33 of the inverter 30, and continues the switching operation of the inverter 30 in the same manner according to the previous duty command. At this time, the first switching module 31, the second switching module 32, and the third switching module 33 are all operated in the same manner according to the previous duty command.

[0085] Therefore, after the abnormal current sensor occurs, the inverter 30 operates with the switching duty according to the previous duty command.

[0086] The inverter 30 maintains the switching operation according to the previous duty command for a predetermined time. That is, the inverter 30 continues the switching operation of the switching modules 31, 32, 33 for the predetermined time in the same manner as immediately before the abnormal current sensor occurs. For example, the predetermined time can be set to a time of 10 times a period in which the current applied to the motor 10 is controlled (i.e., a current control period). For example, if the current control period is 0.1 ms, the time during which the inverter 30 continues the switching operation according to the previous duty command can be 1 ms. As described above, if the duration of the switching operation of the inverter 30 is set, the charging system stably operates.

[0087] That is, the time during which the inverter 30 continues the switching operation according to the previous duty command can be set to a time of 10 times a period in which the current applied to the motor 10 is controlled (i.e., a current control period). For example, if the current control period is 0.1 ms, the time during which the inverter 30 continues the switching operation according to the previous duty command can be 1 ms. As described above, if the duration of the switching operation of the inverter 30 is set, the charging system stably operates.

[0088] When the inverter 30 continues the switching operation in the case where the abnormal current sensor occurs, the possibility of a secondary failure increases.

[0089] Therefore, when it is determined that the abnormal current sensor occurs and the predetermined time has elapsed, the controller 40 gradually reduces the switching duty of the inverter 30, and reduces the switching duty (i.e., the on-duty) of the first switching module 31, the second switching module 32, and the third switching module 33 at the same rate.

[0090] By reducing the on-duty of the switching modules 31, 32, 33 at the same rate, it is possible to maintain the balance of the force acting on the rotor of the motor 10. By reducing the on-duty of the switching modules 31, 32, 33 at the same rate, the on-duty of the switching modules 31, 32, 33 can reach 0% at the same time, thereby preventing the rotational operation of the motor 10.

[0091] When the on-duty of the switching modules 31, 32, 33 is reduced differently, the force acting on the rotor of the motor 10 becomes unbalanced, and thus, the motor 10 operates to generate a motor torque.

[0092] Further, preferably, the switching duty ratio of the inverter 30 is linearly reduced when the switching duty ratio is reduced. At this time, a value derived through a previous experiment or the like can be determined as a reduction ratio of the switching duty ratio.

[0093] The switching duty ratio is reduced from the current switching duty ratio value (i.e., a real-time switching duty ratio value) to 0% within a predetermined time. The switching duty ratio of the inverter 30 is linearly reduced from the real-time switching duty ratio value to 0% within a time of 100 times a period in which the current applied to the motor 10 is controlled (i.e., a current control period). For example, if the current control period is 0.1 ms, the switching duty ratio of the inverter 30 is reduced from the real-time duty ratio value to 0% within 10 ms.

[0094] Here, the secondary fault can be a fault of other components in the charging system, for example, can be a fault of the motor 10.

[0095] When it is confirmed that the switching duty ratio of the inverter 30 is reduced and becomes 0%, the controller 40 can determine that the charging of the battery 20 is stopped, and can transmit a signal indicating that the charging of the battery 20 is stopped (i.e., a charging stop signal) and a signal indicating that the abnormal current sensor occurs (i.e., a sensor fault signal) to the main controller 60.

[0096] To more accurately determine whether the battery 20 is stopped from being charged, the controller 40 can further determine whether the output current of the external charger 50 becomes zero (0 A) when determining whether the switching duty ratio of the inverter 30 becomes zero.

[0097] When it is confirmed that the switching duty ratio of the inverter 30 reaches 0% and it is confirmed that the output current of the external charger 50 becomes zero (0 A), the controller 40 can determine that the charging of the battery 20 is stopped, and then transmit the charging stop signal and the sensor fault signal to the main controller 60.

[0098] The controller 40 can inform the main controller 60 of the reason for the charging of the battery 20 being stopped by transmitting the charging stop signal and the sensor fault signal to the main controller 60, and can also cause the abnormal current sensor to be replaced, repaired, or the like.

[0099] The main controller 60 is a vehicle-mounted controller, and can be a main controller of a motor control unit of a vehicle.

[0100] Here, a description will be made of a battery charging stop method of a charging system according to various exemplary embodiments of the present application with reference to Figure 3 A battery charging stop method of a charging system according to various exemplary embodiments of the present application will be described.

[0101] As Figure 3As shown, the controller 40 monitors and confirms in real time whether an abnormal current sensor has occurred in the current sensors 34, 35, 36 of the inverter 30 while charging the battery 20.

[0102] When it is determined that an abnormal current sensor has occurred, the controller 40 maintains the switching duty ratio of the inverter 30 to be the same as the switching duty ratio immediately before the occurrence of the abnormal current sensor by the duty command (i.e., the previous duty command) transmitted to the inverter 30 immediately before the occurrence of the abnormal current sensor.

[0103] To this end, when it is determined that an abnormal current sensor has occurred, the controller 40 does not transmit a new duty command to the inverter 30.

[0104] That is, when it is determined that any one of the first current sensor 34, the second current sensor 35, and the third current sensor 36 has failed, the controller 40 does not transmit a new duty command to the inverter 30 so that the switching operation can continue according to the switching duty ratio of the previous duty command.

[0105] Because a new duty command is not transmitted from the controller 40, the inverter 30 can continue the switching operation based on the switching duty ratio according to the previous duty command.

[0106] When a predetermined time has elapsed from the occurrence of the abnormal current sensor, the controller 40 linearly reduces the switching duty ratio of the inverter 30. At this time, the on-time of the first switching module 31, the second switching module 32, and the third switching module 33 is gradually reduced based on the switching duty ratio according to the previous duty command.

[0107] When it is determined that the first current sensor 34 that detects the amount of current applied to the first winding 11 has failed, the controller 40 reduces the switching duty ratio of the first switching module 31 at the same ratio as the ratio of the switching duty ratios of the second switching module 32 and the third switching module 33.

[0108] Further, when it is determined that the second current sensor 35 that detects the amount of current applied to the second winding 12 has failed, the controller 40 reduces the switching duty ratio of the second switching module 32 at the same ratio as the ratio of the switching duty ratios of the first switching module 31 and the third switching module 33.

[0109] Further, when it is determined that the third current sensor 36 that detects the amount of current applied to the third winding 13 has failed, the controller 40 reduces the switching duty ratio of the third switching module 33 at the same ratio as the ratio of the switching duty ratios of the first switching module 31 and the second switching module 32.

[0110] When the duty ratio of the switches of the switching modules 31, 32, and 33 is reduced and reaches 0 (0%), the controller 40 confirms whether the output current of the external charger 50 is zero (0 A).

[0111] When it is confirmed that the output current of the external charger 50 is zero, the controller 40 determines that the charging of the battery 20 is stopped, and generates a charging stop signal and a sensor failure signal, thereby transmitting the charging stop signal and the sensor failure signal to the main controller 60.

[0112] When the charging stop signal and the sensor failure signal are received, the main controller 60 outputs a message indicating that the charging of the battery 20 is stopped and a message indicating that the current sensor is faulty to the internal display of the vehicle, thereby being able to notify the user that the charging of the battery 20 is stopped and that the abnormal current sensor occurs.

[0113] Further, the term "controller", "control unit", or "control device" means a hardware device including a memory and a processor configured to perform one or more steps interpreted as an algorithmic structure. The memory stores the algorithmic steps, and the processor performs the algorithmic steps to conduct one or more processes of the method according to various exemplary embodiments of the present application. The controller according to exemplary embodiments of the present application can be implemented by a non-volatile memory configured to store an algorithm for controlling the operation of various components of a vehicle or data on software instructions for executing the algorithm, and a processor configured to perform the above-described operation using the data stored in the memory. The memory and the processor can be separate chips. Alternatively, the memory and the processor can be integrated in a single chip. The processor can be implemented as one or more processors.

[0114] The controller or the control unit can be at least one microprocessor operated by a predetermined program, which can include a series of instructions for performing the method disclosed in the foregoing various exemplary embodiments of the present application.

[0115] The above-described application can also be implemented as computer-readable code on a computer-readable recording medium. The computer-readable recording medium is any data storage device that can store data that can be subsequently read by a computer system. Examples of the computer-readable recording medium include a hard disk drive (HDD), a solid state disk (SSD), a silicon disk drive (SDD), a read-only memory (ROM), a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like, and is implemented as a carrier wave (for example, transmission over the Internet).

[0116] In various exemplary embodiments of the present application, each of the above-described operations can be performed by the controller, and the controller can be composed of a plurality of controllers or an integrated single controller.

[0117] For convenience of explanation and accurate definition of the appended claims, the terms "upper," "lower," "inner," "outer," "over," "under," "upwardly," "downwardly," "front," "rear," "back," "inwardly," "outwardly," "interior," "exterior," "internal," "external," "forward," and "rearward" are used to describe the features of the example embodiments with reference to the positions shown in the drawings. It will be further understood that the terms "connected" or "coupled" or their derivatives, as used throughout this document, are meant to include both direct and indirect connections.

[0118] The foregoing description of specific exemplary embodiments of the application has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the application to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The example embodiments were chosen and described in order to explain the principles of the application and its practical application and to enable others skilled in the art to implement and utilize the application in various example embodiments and various alternative forms and modifications thereof. It is intended that the scope of the application be defined by the claims appended hereto, and their equivalents.

Claims

1. A charging system for a vehicle, the charging system comprising: An electric motor, configured to drive the vehicle; The battery is connected to the motor and supplies power to the motor; An inverter, which is connected between the motor and the battery, and is configured to control the flow of current between the motor and the battery; as well as The controller, which is connected to the inverter, is configured to: when the battery is being charged via the motor and the inverter, and an abnormal current sensor is detected in one of the current sensors connected to the inverter and detecting the amount of current applied to the three-phase windings of the motor, control the switching duty cycle of the inverter according to a previous duty cycle command sent to the inverter before the abnormal current sensor was detected, and then reduce the switching duty cycle of the inverter to zero.

2. The charging system for a vehicle according to claim 1, wherein, The controller is configured to linearly reduce the switching duty cycle of the inverter.

3. The charging system for a vehicle according to claim 1, wherein, When the inverter's switching duty cycle is controlled according to the previous duty cycle command, all switching modules of the inverter operate with the same switching duty cycle according to the previous duty cycle command.

4. The charging system for a vehicle according to claim 3, wherein, The inverter's switching module includes: The first switching module is configured to control the flow of current applied to the first winding of the three-phase winding of the motor; The second switching module is configured to control the flow of current applied to the second winding of the three-phase winding; and The third switching module is configured to control the flow of current applied to the third winding of the three-phase winding.

5. The charging system for a vehicle according to claim 3, wherein, The controller is configured to reduce the switching duty cycle of the first switching module, the second switching module, and the third switching module by the same ratio when the switching duty cycle of the inverter is linearly reduced.

6. The charging system for a vehicle according to claim 1, wherein, The controller is configured to: determine whether the output current of the external charger providing power for charging the battery has become zero when the switching duty cycle of the inverter reaches zero, and the controller is configured to: determine to stop charging the battery when the output current of the external charger becomes zero.

7. The charging system for a vehicle according to claim 2, wherein, The controller is configured to control the switching duty cycle of the inverter according to a previous duty cycle command for a predetermined multiple of the control cycle of the current applied to the motor.

8. The charging system for a vehicle according to claim 3, wherein, The controller is configured to linearly reduce the inverter's switching duty cycle from the real-time switching duty cycle value to 0% within a predetermined multiple of the control cycle of the current applied to the motor.

9. The charging system for a vehicle according to claim 1, wherein, The controller is configured such that when the switching module of the inverter, which controls the flow of current applied to each of the three-phase windings in the motor, is turned on, if the rising slope of the voltage value across at least one winding of the three-phase winding is not the same as the rising slope of the voltage value detected by at least one current sensor, an abnormal current sensor is determined to have occurred.

10. The charging system for a vehicle according to claim 1, wherein, The controller is configured such that when the switching module of the inverter that controls the flow of current applied to each of the three-phase windings in the motor is disconnected, if the rising slope of the voltage value across at least one winding of the three-phase winding is not the same as the rising slope of the voltage value detected by at least one current sensor, an abnormal current sensor is determined to have occurred.

11. A method for stopping battery charging in a charging system for a vehicle, the vehicle including a motor, a battery, and an inverter, the motor being configured to drive the vehicle, the battery being connected to the motor and supplying power to the motor, the inverter being connected to the motor and the battery, the method for stopping battery charging comprising: When the battery is charged via the motor and inverter, the controller determines whether there is an abnormal current sensor in the current sensor, which is connected to the inverter and detects the amount of current applied to the three-phase windings of the motor respectively. When the controller determines that an abnormal current sensor has appeared in the current sensor, the controller controls the switching duty cycle of the inverter according to the previous duty cycle command sent to the inverter before the abnormal current sensor appeared. The controller reduces the inverter's switching duty cycle to zero. When the inverter's switching duty cycle becomes zero, the controller determines that charging of the battery will stop.

12. The method according to claim 11, wherein, When the inverter's switching duty cycle is controlled according to the previous duty cycle command, all switching modules of the inverter operate with the same switching duty cycle according to the previous duty cycle command.

13. The method according to claim 12, wherein, The inverter's switching module includes: The first switching module is configured to control the flow of current applied to the first winding of the three-phase winding of the motor; The second switching module is configured to control the flow of current applied to the second winding of the three-phase winding; and The third switching module is configured to control the flow of current applied to the third winding of the three-phase winding.

14. The method according to claim 13, wherein, The controller is configured to control the inverter's switching duty cycle to reach zero by linearly reducing the inverter's switching duty cycle.

15. The method according to claim 14, wherein, As the inverter's switching duty cycle decreases linearly, the switching duty cycles of the first, second, and third switching modules decrease by the same ratio.

16. The method of claim 11, further comprising: When the inverter's switching duty cycle reaches zero, the controller determines whether the output current of the external charger that provides power for charging the battery has become zero. The controller is configured to stop charging the battery when the output current of the external charger becomes zero.

17. The method according to claim 15, wherein, The controller is configured to control the switching duty cycle of the inverter according to a previous duty cycle command for a predetermined multiple of the control cycle of the current applied to the motor.

18. The method according to claim 11, wherein, The controller is configured to linearly reduce the inverter's switching duty cycle from the real-time switching duty cycle value to 0% within a predetermined multiple of the control cycle of the current applied to the motor.

19. The method according to claim 11, wherein, The controller is configured such that when the switching module of the inverter, which controls the flow of current applied to each of the three-phase windings in the motor, is turned on, if the rising slope of the voltage value across at least one winding of the three-phase winding is not the same as the rising slope of the voltage value detected by at least one current sensor, an abnormal current sensor is determined to have occurred.

20. The method according to claim 11, wherein, The controller is configured such that when the switching module of the inverter that controls the flow of current applied to each of the three-phase windings in the motor is disconnected, if the rising slope of the voltage value across at least one winding of the three-phase winding is not the same as the rising slope of the voltage value detected by at least one current sensor, an abnormal current sensor is determined to have occurred.

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