Control device

Abstract

To provide a control device capable of appropriately discharging an electric charge of a capacitor in a battery charger while suppressing temperature rise of a limiting resistor.SOLUTION: A control device 200 according to the present disclosure is a control device of a vehicle comprising smoothing capacitors 125 and 140 that are present between a system power supply (external power supply) 10 and a power storage device (vehicle battery) 20, a precharge resistor (limiting resistor) 115 for limiting an output current from the system power supply 10, and an IGBT switch (discharge element) 135 capable of discharging charged electrical charges of the smoothing capacitors 125 and 140. After a power supply of the vehicle is turned on, the control device 200 discharges the charged electrical charges when temperature of the precharge resistor 115 is less than a predetermined value; determines whether or not a driver has a travel intention based on vehicle travel information of the vehicle when the temperature of the precharge resistor 115 is a predetermined value or more; and discharges the charged electrical charges when it is determined that the driver has the travel intention.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a control device. [Background technology]

[0002] There is a known technology for discharging the charge of a capacitor used in a vehicle's electric drive system when the vehicle crashes. Discharging the capacitor prevents high-voltage parts from being exposed to the outside, and reduces the risk of leakage current and electric shock. In order to avoid these risks, it is desirable to discharge the capacitor quickly after detecting a vehicle crash. However, when discharging the capacitor quickly, it is necessary to keep in mind that the heat generated by the discharge circuit increases.

[0003] In order to address such problems, for example, Patent Document 1 discloses a vehicle including a first battery used as a driving power source for a driving motor, a smoothing capacitor connected in parallel to the first battery, and a discharge circuit connected in parallel to the smoothing capacitor and capable of discharging the charge of the smoothing capacitor. The vehicle also includes a discharge control unit that controls the operation of the discharge circuit, and a collision detection unit that detects an object collision with the vehicle. When the discharge control unit detects at least the occurrence of an abnormality that makes it impossible to detect the detection of an object collision by the collision detection unit, the discharge control unit causes the discharge circuit to discharge the charge of the smoothing capacitor at high speed. When the discharge control unit detects neither the occurrence of the abnormality nor the detection of the object collision by the collision detection unit, the discharge control unit causes the discharge circuit to discharge the charge of the smoothing capacitor at low speed. In this way, the technology disclosed in Patent Document 1 prevents the discharge circuit from overheating by performing high-speed discharge in urgent situations such as vehicle collisions, and performing low-speed discharge in other situations. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6378267 Summary of the Invention [Problem to be solved by the invention]

[0005] A charger mounted on a vehicle has a capacitor therein, and the capacitor accumulates electric charge by charging the vehicle battery. It is desirable for such a capacitor to discharge electric charge except when charging the vehicle battery. For example, it is possible to discharge the electric charge of the capacitor when the power supply of the vehicle is turned on. However, a limiting resistor for limiting an inrush current from an external power supply is provided in the charger, and this limiting resistor operates when charging is performed in a state in which the electric charge of the capacitor is discharged. Therefore, if the capacitor is discharged every time the power supply is turned on, this limiting resistor may overheat if charging and power ON are repeated in a short period of time. If the limiting resistor overheats, problems such as the inability to charge the vehicle battery or a fault determination of the vehicle may occur.

[0006] The present disclosure has been made in consideration of the above circumstances, and provides a control device that is capable of appropriately discharging the charge of a capacitor in a charger while suppressing a temperature rise in a limiting resistor. [Means for solving the problem]

[0007] The control device according to the present disclosure includes: A capacitor between the external power supply and the vehicle battery; a limiting resistor that limits an output current from the external power supply to the capacitor; A vehicle control device including: After turning on the vehicle power, When the temperature of the limiting resistor is less than a predetermined value, the charged charge is discharged. When the temperature of the limiting resistor is equal to or higher than a predetermined value, a determination is made as to whether or not the driver has the intention to drive the vehicle based on vehicle driving information of the vehicle, and when it is determined that the driver has the intention to drive, the charged charge is discharged. Effect of the Invention

[0008] The control device according to the present disclosure makes it possible to appropriately discharge the charge of the capacitor in the charger while suppressing the temperature rise of the limiting resistor. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a configuration of a charging system according to an embodiment; [Diagram 2] 5 is a flowchart showing a process of a control device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Fig. 1 is a block diagram showing the configuration of a charging system 1000 according to this embodiment. The charging system 1000 includes a system power supply (external power supply) 10, a charger 100, a power storage device (vehicle battery) 20, and a control device 200. Note that the configuration shown in Fig. 1 is merely an example, and each functional unit of the charging system 1000 may be configured using a device in which multiple components are integrated. For example, the functions of the charger 100 and the control device 200 may be integrated into the same device. Also, for example, each functional unit in the control device 200 and the charger 100 may be distributed and processed using multiple devices.

[0011] The system power supply 10 supplies power to the charger 100 via a charging cable or the like. The system power supply 10 may be, for example, a power supply that receives a supply of AC power from a power grid provided by an electric utility company.

[0012] The power storage device 20 is a rechargeable DC power source. The power storage device 20 includes a secondary battery, such as a lithium ion battery or a nickel-metal hydride battery. As an example, in this embodiment, a battery pack including a plurality of lithium ion batteries is used as the secondary battery. The battery pack is configured by electrically connecting a plurality of single batteries (generally also referred to as "cells") to each other. Note that, instead of the secondary battery, another power storage device, such as an electric double layer capacitor, may be used.

[0013] The charger 100 is connected to a system power supply 10, a power storage device 20, and a control device 200. The charger 100 receives power from the system power supply 10, and uses the supplied power to charge the power storage device 20. The charger 100 also operates in accordance with a control signal from the control device 200.

[0014] As shown in FIG. 1, the charger 100 includes a precharge circuit 110, an input filter 120, a PFC (Power Factor Correction) circuit 130, a smoothing capacitor 140, a DC-DC converter 150, a voltage sensor 160, and a temperature sensor 170.

[0015] The precharge circuit 110 is configured to switch the power path between the system power supply 10 side and the input filter 120. For example, the precharge circuit 110 includes a precharge resistor 115, a fuse 117, and a precharge relay 116. The precharge resistor 115 is a limiting resistor that limits the output current from the system power supply 10 to the smoothing capacitors 125 and 140 of the charger 100. The precharge resistor 115 and the fuse 117 are connected in series with each other. The precharge relay 116 is connected in parallel with the precharge resistor 115 and the fuse 117.

[0016] The precharge relay 116 is opened and closed based on a control signal from the control device 200. When the precharge relay 116 is in an open state, the current passing through the precharge circuit 110 toward the input filter 120 is limited by the precharge resistor 115. Therefore, by keeping the precharge relay 116 in an open state, the smoothing capacitors 125 and 140 can be charged (so-called precharge) while preventing an inrush current to the smoothing capacitors 125 and 140. In addition, after the precharge is completed, by closing the precharge relay 116, the smoothing capacitors 125 and 140 can be charged without being limited by the precharge resistor 115. Note that the configuration of the precharge circuit 110 is not limited to the above-mentioned form, and any configuration may be used.

[0017] The input filter 120 operates in accordance with a control signal from the control device 200. The input filter 120 smoothes the voltage fluctuation of the AC power output from the precharge circuit 110 using a smoothing capacitor 125. The smoothing capacitor 125 is connected in parallel with the system power supply 10. The smoothing capacitor 125 accumulates the charge output from the precharge circuit 110. The charge accumulated in the smoothing capacitor 125 can be discharged by an IGBT (Insulated Gate Bipolar Transistor) switch 135.

[0018] The PFC circuit 130 operates according to a control signal from the control device 200. The PFC circuit 130 performs a predetermined power conversion on the power output from the input filter 120, and efficiently outputs a charging current to the DC-DC converter 150. The PFC circuit 130 has an IGBT switch 135 capable of discharging the charges of the smoothing capacitors 125 and 140. It is to be noted that the PFC circuit 130 is not limited to an IGBT switch, and any discharge element capable of consuming the charges of the smoothing capacitors 125 and 140 may be used. For example, a semiconductor element such as a FET (Field effect transistor) may be used. Also, an ordinary switch or an element capable of switching a current by an on / off operation such as a relay may be used.

[0019] The smoothing capacitor 140 accumulates the charge output from the PFC circuit 130. Furthermore, the smoothing capacitor 140 smoothes the voltage fluctuation of the DC power output from the PFC circuit 130. The charge accumulated in the smoothing capacitor 140 can be discharged by the IGBT switch 135.

[0020] The voltage sensor 160 measures the voltage VH on the input side of the DC-DC converter 150 . The DC-DC converter 150 increases the output power from the PFC circuit 130 to the battery voltage in accordance with a control signal from the control device 200. The step-up ratio may be determined using the voltage VH acquired by the voltage sensor 160. The temperature sensor 170 measures the temperature of the precharge resistor 115 and acquires temperature information. The temperature sensor 170 outputs the temperature information to the control device 200.

[0021] The control device 200 is a device that controls each functional unit of the charger 100 described above, and controls the charging process and discharging process in the charger 100. The control device 200 may be connected to devices other than the charger 100 mounted on the vehicle, and configured to be able to control the operation of the connected devices. For example, the control device 200 is connected to sensors such as a vehicle speed sensor and a shift position sensor (neither of which are shown) for detecting the running state of the vehicle, and controls these.

[0022] 1, the control device 200 includes a vehicle control unit 210, an acquisition unit 220, a determination unit 230, and a charge / discharge control unit 240. Although the control device 200 is shown outside the charger 100 in the figure, the present invention is not limited to this. The control device 200 may be built into the charger 100.

[0023] The vehicle control unit 210 controls the operation of the vehicle. For example, the vehicle control unit 210 transitions the power supply of the vehicle to a ReadyON (system activated) state or a ReadyOFF (system stopped) state. The ReadyON state and the ReadyOFF state may correspond to the ON state and the OFF state of the power supply of the vehicle, respectively.

[0024] The acquisition unit 220 acquires information detected by sensors mounted on the vehicle. The acquisition unit 220 may acquire information from the sensors at any timing. For example, the acquisition unit 220 acquires temperature information of the precharge resistor 115 from the temperature sensor 170.

[0025] The acquisition unit 220 also acquires vehicle driving information related to the driving of the vehicle from sensors. The vehicle driving information may be, for example, information indicating the vehicle speed acquired from a vehicle speed sensor, the shift lever position acquired from a shift position sensor, etc. The vehicle driving information is not limited to these, and may include various information acquired from sensors.

[0026] After the vehicle transitions to the ReadyON state, the determination unit 230 determines whether the temperature of the precharge resistor 115 is below a predetermined value based on the temperature information of the precharge resistor 115 acquired by the acquisition unit 220. The predetermined value may be set in advance and stored in a storage device (not shown). The determination unit 230 may measure the elapsed time since the temperature of the precharge resistor 115 became below the predetermined value with a timer (not shown), and may determine that the temperature of the precharge resistor 115 has become below the predetermined value when the predetermined time has elapsed. The predetermined time may also be set in advance and stored in the storage device.

[0027] Furthermore, when the determination unit 230 determines that the temperature of the precharge resistor 115 is equal to or higher than the predetermined value, it determines whether or not the driver has an intention to drive the vehicle based on the vehicle driving information acquired by the acquisition unit 220. Here, the driver's intention to drive the vehicle may be information indicating that the driver is about to start driving the vehicle.

[0028] For example, when the vehicle speed is detected by a vehicle speed sensor, the determination unit 230 determines that the driver has the intention to drive. The determination unit 230 may determine that the driver has the intention to drive when the vehicle speed is equal to or greater than a predetermined threshold. The determination unit 230 may also determine whether or not the driver has the intention to drive based on the driver's shift operation. For example, when the shift lever position is in "drive" or "reverse" or when the parking brake is released, the determination unit 230 determines that the driver has the intention to drive. In addition to the above, the determination unit 230 may determine whether or not the driver has the intention to drive based on information detected from any sensor.

[0029] The charge / discharge control unit 240 controls the charging and discharging processes in the charger 100. For example, when the system power supply 10 and the charger 100 are connected, the charge / discharge control unit 240 controls the precharge circuit 110 so that the precharge relay 116 is in an open state. This forms a power path via the precharge resistor 115, and allows the smoothing capacitors 125 and 140 to be precharged. After the precharge is completed, the charge / discharge control unit 240 controls the precharge circuit 110 so that the precharge relay 116 is in a closed state. This allows the smoothing capacitors 125 and 140 to be charged without being restricted by the precharge resistor 115.

[0030] Furthermore, the charge / discharge control unit 240 controls the IGBT switch 135 to discharge the charges stored in the smoothing capacitors 125 and 140 based on the result of the determination by the determination unit 230. When it is determined that the temperature of the pre-charge resistor 115 is less than a predetermined value, the charge / discharge control unit 240 controls to discharge the charges stored in the smoothing capacitors 125 or 140. When it is determined that the temperature of the pre-charge resistor 115 is not less than the predetermined value and it is determined that the driver has the intention to drive, the charge / discharge control unit 240 controls to discharge the charges stored in the smoothing capacitors 125 or 140.

[0031] Next, the process executed by the control device 200 according to the present embodiment will be described with reference to Fig. 2. Fig. 2 is a flowchart showing the control process executed by the control device 200.

[0032] The charge / discharge control unit 240 controls the charger 100 to charge the power storage device 20 from the system power supply 10, and accumulates electric charge in the smoothing capacitors 125 and 140 (S102). The charge / discharge control unit 240 controls the precharge circuit 110 to perform precharge, thereby preventing inrush current to the smoothing capacitors 125 and 140. In addition, the charge / discharge control unit 240 controls the precharge circuit 110 so that charging is possible without being restricted by the precharge resistor 115 after the precharge is completed.

[0033] The vehicle control unit 210 transitions the vehicle from the ReadyOFF state to the ReadyON state (S104). The acquisition unit 220 acquires temperature information of the precharge resistor 115 from the temperature sensor 170, and the determination unit 230 determines whether the temperature is below a predetermined value (S106). The determination unit 230 measures the elapsed time since the temperature became below the predetermined value, and may determine that the temperature is below the predetermined value if the predetermined time or more has elapsed.

[0034] If it is determined that the temperature of the pre-charge resistor 115 is less than the predetermined value (YES in S106), the charge / discharge control unit 240 controls the IGBT switch 135 to perform a discharge process for the smoothing capacitors 125 and 140 (S108), and ends the process. If it is determined in the process of step S106 that the temperature of the pre-charge resistor 115 is equal to or higher than the predetermined value (NO in S106), it can be said that the pre-charge resistor 115 is in an overheated state. Therefore, the discharge process is not performed as it is, and the process proceeds to step S110.

[0035] The acquisition unit 220 acquires vehicle driving information from sensors, and the determination unit 230 determines whether or not the driver has the intention to drive based on the vehicle driving information (S110). For example, when the vehicle speed is detected by a vehicle speed sensor, the determination unit 230 determines that the driver has the intention to drive. The determination unit 230 may determine that the driver has the intention to drive when the vehicle speed is equal to or greater than a predetermined threshold. Without being limited to this, the determination unit 230 may determine whether or not the driver has the intention to drive based on the driver's shift operation, etc.

[0036] If it is determined that the driver does not intend to drive (NO in S110), the process returns to step S106 and repeats the subsequent processes. In this manner, it is possible to prevent the smoothing capacitors 125 and 140 from discharging until the temperature of the pre-charge resistor 115 falls below a predetermined value or until it is determined that the driver intends to drive. Therefore, even if charging and the ReadyON state are repeated in a short period of time, it is possible to prevent the pre-charge resistor 115 from overheating.

[0037] When it is determined in the process of step S110 that the driver has the intention to drive (YES in S110), the charge / discharge control unit 240 controls the IGBT switch 135 to perform a discharge process of the smoothing capacitors 125 and 140 (S108). In this way, it is possible to prevent high-voltage parts from being exposed to the outside in the event of a vehicle collision, etc., thereby reducing the risk of electric leakage, electric shock, etc.

[0038] As described above, according to the charging system 1000 of this embodiment, the control device 200 judges whether or not the temperature of the pre-charge resistor 115 is below a predetermined value after the vehicle is in a ReadyON (power ON) state. If the temperature of the pre-charge resistor 115 is below the predetermined value, the control device 200 discharges the smoothing capacitors 125 and 140, and if not, judges whether or not the driver has the intention to drive, and performs different processing depending on the result of the judgment. If it is judged that the driver has the intention to drive, the control device 200 discharges the smoothing capacitors 125 and 140, and if not, does not perform the discharge processing until the temperature of the pre-charge resistor 115 drops or it is judged that the driver has the intention to drive.

[0039] In this way, the control device 200 can control discharging in consideration of not only the transition of the vehicle to the ReadyON state, but also the temperature state of the pre-charge resistor 115 and the driver's intention to drive. In this way, the control device 200 can appropriately discharge the charges of the smoothing capacitors 125 and 140 in the charger 100 while suppressing a temperature rise in the pre-charge resistor 115. This can reduce the risk of leakage current, electric shock, and the like in the event of a vehicle collision, etc.

[0040] <Hardware configuration example> The control device 200 and the charger 100 may be implemented by hardware (e.g., hardwired electronic circuits, etc.) that realizes each of the above-mentioned functions, or may be implemented by a combination of hardware and software (e.g., a combination of electronic circuits and a program that controls the electronic circuits, etc.). For example, the present disclosure may be implemented by having a central processing unit (CPU) execute a computer program. The program includes a set of instructions (or software code) that, when loaded into a computer, causes the computer to perform one or more functions described in the embodiments. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not of limitation, the computer-readable medium or tangible storage medium may include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disc (DVD), Blu-ray (registered trademark) disk or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The program may be transmitted on a transitory computer-readable medium or a communication medium. By way of example, and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

[0041] The present disclosure is not limited to the above-described embodiment, and can be modified as appropriate without departing from the spirit and scope of the present disclosure. [Explanation of symbols]

[0042] 10 Grid power supply 20. Energy storage device 100 charger 110 Precharge Circuit 115 Precharge Resistor 116 Precharge Relay 117 Fuse 120 Input Filter 125 Smoothing capacitor 130 PFC circuit 135 IGBT Switch 140 Smoothing capacitor 150 DC-DC Converter 160 Voltage Sensor 170 Temperature Sensor 200 Control device 210 Vehicle control unit 220 Acquisition Department 230 Judgment section 240 Charge / discharge control unit 1000 Charging System

Claims

[Claim 1] A capacitor between the external power supply and the vehicle battery; a limiting resistor that limits an output current from the external power supply to the capacitor; A vehicle control device including: After turning on the power of the vehicle, When the temperature of the limiting resistor is less than a predetermined value, the charged charge is discharged. When the temperature of the limiting resistor is equal to or higher than a predetermined value, it is determined whether or not the driver has an intention to drive the vehicle based on vehicle driving information of the vehicle, and when it is determined that the driver has an intention to drive the vehicle, the charged charge is discharged. Control device.

Images