JP2005160227A - Vehicle control system, vehicle control method and vehicle control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control a vehicle control system so as to obtain desired power in accordance with a detected voltage. <P>SOLUTION: A converter ECU 70 receives a detected voltage value transmitted from an integrated ECU device 60 by an analog signal via a communication line 100, and receives a detected voltage value transmitted from the integrated ECU device 60 by a digital signal via a communication line 120. The converter ECU 70 corrects the detected voltage value indicated by the analog signal on the basis of the comparison of the received detected voltage value indicated by the analog signal and the received detected voltage value indicated by the digital signal, and corrects and controls a DC-DC converter on the basis of the comparison of the corrected detected voltage value of the analog signal and a feed voltage value necessary for the drive of a vehicle drive motor calculated on the basis of an accelerator opening. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle control system, and more particularly to a vehicle control system that supplies electric power output from a power supply device to a load device provided in the vehicle.

  Conventionally, as a vehicle control system mounted on a vehicle, for example, a system as shown in FIG. 14 has been proposed. In such a vehicle control system, a plurality of electronic control devices 1 are provided, and each electronic control device controls the entire vehicle control system by exchanging control signals with each other. Then, by being controlled by each electronic control device, the input voltage from the power supply device 2 is DC / DC converted by the DC / DC converter 3, and the DC / DC converted output voltage is converted by the inverter circuit 4 to the polyphase alternating current. The electric motor 5 is rotationally driven in response to the multiphase AC voltage converted into voltage.

  As described above, in the vehicle control system mounted on the vehicle, the supply voltage calculated based on the load request from the electric motor 5 under the control of each electronic control device can be taken out from the power supply device 2 such as a battery or a fuel cell. As described above, the DC / DC converter 3 is controlled to ensure stable driving. However, due to the influence of the internal resistance of the power supply device 2 and the like, an error may occur between the actual voltage actually output and the supply voltage calculated based on the load request. Therefore, the voltage detection sensor 6 detects the voltage output from the DC / DC converter 3, and each electronic control unit performs correction control on each control object based on the detected voltage, so that the output voltage Correction is performed and control is performed so as to obtain a desired power for the load request. Here, data indicating the voltage value of the voltage used by each electronic control unit to correct and control each control object is exchanged via a communication line such as a wire harness.

JP 2000-159106 A

  However, the voltage value of the voltage used as the correction control parameter exchanged between each electronic control device has an error due to the influence of the resistance of the communication line connecting each electronic control device, and the output power correction is properly performed. Otherwise, desired power corresponding to the load demand may not be obtained.

  The present invention has been made in view of the above problems, and an object of the present invention is to control a vehicle control system so as to obtain a desired power according to a load request.

  According to the vehicle control system of the present invention, a power supply device including a converter on the output side is connected to a load device including a vehicle drive motor, and according to a supply voltage value calculated based on a required load from the load device. In a vehicle control system for driving an electric vehicle by supplying power from the power supply device to the load device and driving the vehicle drive motor, the converter control device for controlling the converter is supplied from the power supply device. Receiving means for receiving, as an analog signal, a detection voltage value transmitted from a detection device that detects a voltage value of the voltage to the vehicle drive motor, and the detection voltage value received from the detection device An analog signal transmitting means for transmitting an analog signal as an analog signal, and an analog signal indicating the detection voltage value received from the detection device, A digital signal transmission unit that converts the digital signal into a digital signal and outputs the detected voltage value transmission device, and the converter control device transmits the detection voltage value transmitted as an analog signal from the detection voltage value transmission device to a communication line. An analog signal receiving means for receiving via a communication voltage, a digital signal receiving means for receiving the detected voltage value transmitted as a digital signal from the detected voltage value transmitting device via a communication line, and the received analog signal Based on a comparison between the detected voltage value and the detected voltage value indicated in the received digital signal, the detected voltage value correcting means for correcting the detected voltage value indicated by the analog signal, and the detected voltage value correcting means corrects the detected voltage value. Correction control means for correcting and controlling the converter based on a comparison between the detected voltage value of the analog signal and the supply voltage value.

  According to the present invention, the converter is corrected and controlled based on the comparison between the detected voltage value of the analog signal corrected by the detected voltage value correcting unit and the supply voltage value.

  Therefore, based on the detected voltage value received with a digital signal that is less affected by the voltage drop of the communication line, even if an error occurs due to the detected voltage value of the analog signal caused by the voltage drop of the communication line, etc. Since the correction can be made with the calculated correction value, the influence of the voltage drop of the communication line can be suppressed, and desired power can be supplied to the vehicle drive motor.

  According to another aspect of the vehicle control system of the present invention, there is provided a power supply device in which a first power source including a fuel cell and a second power source including a converter on the output side of the secondary battery are connected in parallel. A converter control device that is connected to a load device including a drive motor, controls the converter according to a supply voltage value calculated based on a required load from the load device, and controls an output from the first power source. In the vehicle control system for driving an electric vehicle by supplying electric power from the first power source and / or the second power source to the load device and driving the vehicle drive motor, the power source device is supplied from the power source device. Receiving means for receiving the detected voltage value transmitted from the detecting device for detecting the voltage value of the voltage to the load device as an analog signal via a communication line, and the detected voltage value received from the detecting device. A detection voltage value transmission comprising: an analog signal transmission means for transmitting an analog signal as an analog signal; and a digital signal transmission means for converting the analog signal indicating the detection voltage value received from the detection device into a digital signal and outputting the digital signal. The converter control device includes an analog signal receiving means for receiving the detected voltage value transmitted as an analog signal from the detected voltage value transmitting device via a communication line, and a digital signal transmitted from the detected voltage value transmitting device. Based on the comparison of the detected voltage value shown in the received digital signal, the detected voltage value shown in the received analog signal, the digital signal receiving means for receiving the detected voltage value that is received via the communication line, Detection voltage value correction means for correcting the detection voltage value indicated by the analog signal, and the analog signal corrected by the detection voltage value correction means A detection voltage value, based on a comparison between said supply voltage value, characterized in that it comprises a correction control means for correcting control the converter.

  According to the present invention, the converter is corrected and controlled based on the comparison between the detected voltage value of the analog signal corrected by the detected voltage value correcting means of the converter control device and the supply voltage value.

  Therefore, based on the detected voltage value received with a digital signal that is less affected by the voltage drop of the communication line, even if an error occurs due to the detected voltage value of the analog signal caused by the voltage drop of the communication line, etc. Since the correction can be made with the calculated correction value, the influence of the voltage drop of the communication line can be suppressed, and desired power can be supplied to the vehicle drive motor. Furthermore, the converter control device recognizes the received detection voltage value lower than the detection voltage value actually detected by the detection device due to the influence of the voltage drop of the communication line, etc. It is possible to prevent the desired power from being supplied to the vehicle drive motor and causing a reduction in fuel consumption.

  According to another aspect of the vehicle control system of the present invention, the load device outputs an inverter that converts a direct current output from the power supply device into an alternating current, and controls the inverter to output the load device from the inverter. An inverter control device that controls a current input to the vehicle drive motor, wherein the inverter control device sends the detected voltage value transmitted from the detected voltage value transmission device as an analog signal via a communication line. An analog signal receiving means for receiving, a digital signal receiving means for receiving the detected voltage value transmitted as a digital signal from the detected voltage value transmitting device via a communication line, and a detected voltage value indicated by the received analog signal And a detection voltage value correction that corrects the detection voltage value indicated by the analog signal based on a comparison of the detection voltage value indicated by the received digital signal. Based on stage and, detecting the voltage value of the corrected analog signal by the detection voltage value correcting means, characterized in that it comprises a current correction control means for correcting control the output current from the inverter.

  According to the present invention, the inverter control device corrects and controls the output current from the inverter based on the detected voltage value of the analog signal corrected by the detected voltage value correcting means.

  Therefore, the inverter control device recognizes the received detection voltage value lower than the detection voltage value actually detected by the detection device due to the voltage drop of the communication line, etc., so that the amount of current output from the inverter is reduced. It is possible to prevent an increase in the amount of current that is assumed, leading to an overcurrent breakage of the inverter or the vehicle drive motor, an increase in motor power consumption, an overoutput torque of the motor, or the like.

  Hereinafter, a first embodiment of the present invention (hereinafter referred to as a first embodiment) will be described with reference to the drawings.

  First, before describing this embodiment, a conventional vehicle control system will be described. FIG. 1 is a configuration diagram showing a configuration of a conventional vehicle control system. The vehicle control system includes a power source 10, a converter 20 that performs DC / DC conversion on an input voltage of the power source 10, and an inverter circuit 30 that converts DC power output from the DC / DC converter 20 into three-phase AC power. And a vehicle drive motor 40 that drives the electric vehicle with the three-phase AC power output from the inverter circuit 30.

  Further, the vehicle control system includes an overall ECU (electronic control unit) 60 that controls the entire system, a converter ECU 70 that controls the DC / DC converter 20 based on a control signal from the overall ECU, and a control signal also from the overall ECU. And an inverter ECU 80 for controlling the inverter circuit 30 based on the above. Although not shown, each ECU is configured as a microprocessor centered on a CPU, and includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and the like.

  In the vehicular control system configured as described above, conventionally, a driving flow as shown in FIG. 2 has been executed under the control of each ECU.

  That is, the total ECU 60 calculates the voltage value of the output voltage to be output from the DC / DC converter 20 to the inverter circuit 30 as the supply voltage value based on the accelerator opening detected by the accelerator sensor (not shown). (S101). Then, the general ECU 60 transmits the calculated supply voltage value to the converter ECU 70 as an analog signal via the analog communication line 100 (S102). Converter ECU 70 receives the analog signal indicating the supply voltage value, and controls DC / DC converter 20 based on the supply voltage value indicated by the analog signal (S103). The DC / DC converter 20 is controlled by the converter ECU 70 to convert the voltage output from the power supply 10 into a supply voltage value and output it (S104). Thereby, the electric power according to the accelerator opening degree is supplied to the vehicle drive motor 40, and the electric vehicle can be driven.

  However, in reality, due to the influence of the internal resistance of the power supply 10, the voltage value of the voltage output from the DC / DC converter 20 has an error from the supply voltage value calculated by the general ECU 60. In order to compensate for the error, the conventional vehicle control system includes a voltage detection sensor 50 that detects a voltage output from the DC / DC converter 20, that is, a voltage input to the inverter circuit 30. And the correction flow as shown in FIG. 3 was performed.

  In FIG. 3, the voltage detection sensor 50 transmits the detected voltage value of the detected voltage as an analog signal to the general ECU 60 via the analog communication line 110 (S111). The total ECU 60 transmits an analog signal indicating the received detection voltage value to the converter ECU 20 as an analog signal via the analog communication line 100 (S112). Then, converter ECU 70 calculates the difference between the detected voltage value indicated by the received analog signal and the supply voltage value (S113). It is determined whether or not the calculated difference exceeds a predetermined error allowable range (S114). If the result of determination indicates that the calculated difference exceeds the predetermined error allowable range, the converter ECU 20 subsequently determines that the difference is greater than the supply voltage value. It is determined whether or not the detected voltage value is high (S115). If the detected voltage value is lower than the supply voltage value as a result of the determination, the DC / DC converter 20 is corrected and controlled to increase the voltage output from the DC / DC converter 20 (S116). If the detected voltage value is higher than the supply voltage value, the DC / DC converter 20 is corrected and controlled to lower the voltage output from the DC / DC converter 20 (S117).

  Thereby, the error between the voltage value of the voltage actually output from the DC / DC converter 20 and the supply voltage value calculated by the total ECU 60 can be reduced due to the influence of the internal resistance of the power supply 10 and the like.

  However, as described above, in the conventional vehicle control system, the following problem occurs even when converter ECU 70 performs correction control on DC / DC converter 20 based on the detected voltage value detected by voltage detection sensor 50. .

  That is, in the vehicle control system, the load fluctuation with respect to the vehicle drive motor is severe, and it is necessary to supply power corresponding to the accelerator opening detected by the accelerator sensor to the vehicle drive motor as soon as possible. Therefore, in order to correct the voltage output from the DC / DC converter 20, the detection voltage value received by the general ECU 60 from the voltage detection sensor 50 is also transmitted to the converter ECU 70 without communication delay, and correction control of the DC / DC converter 20 is performed. It is desirable to do. Therefore, the time taken for the A / D conversion process or the like when the integrated ECU 60 transmits the detected voltage value received as an analog signal from the voltage detection sensor 50 to the converter ECU 70 without converting it into a digital signal. In the past, communication between ECUs was performed using analog signals.

  However, if the detection voltage value is transmitted as an analog signal, the detection voltage value is not accurately transmitted to the converter ECU 70 due to the voltage drop of the communication line such as the wire harness, and the detection voltage recognized between the ECUs. An error may occur in the value. Therefore, even when converter ECU 70 performs the correction control of DC / DC converter 20 as described above based on the detected voltage value received as an analog signal, the received detected voltage value itself has an error, and the desired power can be obtained. The subject that it cannot supply to a vehicle drive motor arises. In order to solve this problem, it is conceivable that the detected voltage value is not an analog signal but a digital signal that is less affected by a voltage drop or the like to communicate with each ECU and perform correction control. However, as described above, when communication is performed between ECUs using digital signals and correction control is performed, a communication delay occurs due to the influence of A / D conversion processing and the like, and accordingly, according to the accelerator opening detected by the accelerator sensor. It becomes difficult to quickly supply power to the vehicle drive motor.

  Therefore, in this embodiment, a system configuration as shown in FIG. 4 is adopted. In the present embodiment, what is characteristic is that the general ECU 60 not only transmits the detection voltage value received from the voltage detection sensor 50 as an analog signal to the converter ECU 70 via the analog communication line 100 but also digital communication. The detected voltage value is transmitted to the converter ECU 70 via the line 120 even with a digital signal. And converter ECU70 correct | amends the detection voltage value used as a control parameter of DC / DC converter 20 based on the detection voltage value received with the analog signal and the digital signal before performing correction control, and communication An error between the actual detected voltage value and the detected voltage value recognized by converter ECU 70 can be eliminated due to the influence of a voltage drop of the line, and desired electric power can be supplied to the vehicle drive motor.

  Specifically, description will be made based on the flowchart shown in FIG. In FIG. 5, first, the general ECU 60 transmits the detection voltage value received from the voltage detection sensor 50 as an analog signal to the converter ECU 70 via the analog communication line 100 as an analog signal, and the received detection voltage value. It converts into a digital signal, and transmits to converter ECU70 via the digital communication line 120 (S121). Converter ECU 70 determines the detected voltage value received by a digital signal that is less affected by a voltage drop or the like as a reference detected voltage value, and calculates the difference between the detected reference voltage value and the detected voltage value received by an analog signal (S122). ). The calculation result is stored as a correction value of the detected voltage value of the analog signal in a memory provided inside or outside of converter ECU 70 (S123).

  Subsequently, converter ECU 70 executes a correction control process as shown in the flowchart shown in FIG. In FIG. 6, the voltage detection sensor 50 transmits the voltage value of the detected voltage as an analog signal to the general ECU 60 via the analog communication line 110 (S131). The total ECU 60 transmits an analog signal indicating the received detection voltage value to the converter ECU 20 as an analog signal via the analog communication line 100 (S132). Subsequently, the detected voltage value indicated by the received analog signal is corrected with the correction value stored in the memory (S133). Specifically, if the detected voltage value received by the analog signal is smaller than the reference detected voltage value, the stored correction value is added to the detected voltage value indicated by the received analog signal, and then the correction is performed. If it is larger, correction is performed by subtracting the stored correction value.

  Then, converter ECU 70 calculates the difference between the corrected detected voltage value and the supply voltage value (S134). Further, it is determined whether or not the calculated difference exceeds a predetermined error allowable range (S135). If the result of determination indicates that the calculated difference exceeds the predetermined error allowable range, converter ECU 20 then continues to supply voltage value. It is determined whether or not the corrected detection voltage value is higher (S136). As a result of the determination, if the corrected detection voltage value is lower than the supply voltage value, the DC / DC converter 20 is corrected and controlled to increase the voltage output from the DC / DC converter 20 (S137). If the detected voltage value is higher than the supply voltage value, the DC / DC converter 20 is corrected and controlled to lower the voltage output from the DC / DC converter 20 (S138).

  As a result, by performing communication between ECUs with analog signals and performing correction control, not only can communication delay be suppressed, but the detected voltage value received with analog signals is affected by the voltage drop of the communication line, etc. Even if an error occurs, it is corrected with a correction value calculated in advance based on the detected voltage value received with a digital signal that is less affected by the voltage drop of the communication line, etc., so that the influence of the voltage drop of the communication line is suppressed. The desired electric power can be supplied to the vehicle drive motor.

  Next, a second embodiment of the present invention (hereinafter referred to as a second embodiment) will be described with reference to the drawings. Embodiment 2 relates to a vehicle control system that drives an electric vehicle using a fuel cell.

  FIG. 7 is a system configuration diagram of the vehicle control system according to the second embodiment. The fuel cell vehicle equipped with the present system includes a fuel cell 90 and a secondary battery 91 as a power supply device that supplies power to the vehicle drive motor 41. Then, electric power is supplied from the fuel cell 90 or the secondary battery 91 to the vehicle drive motor 41 via the inverter circuit 31, and the vehicle is driven.

  The fuel cell 90 is configured, for example, as a solid polymer fuel cell, and is supplied with hydrogen as a fuel supplied from a hydrogen tank and air as a gas containing oxygen supplied from a blower. Power is generated by chemical reaction. The fuel cell 90 is controlled by a general ECU 60 that controls the entire system. A dedicated ECU may be provided for controlling the fuel cell 90. The secondary battery 91 is configured as, for example, a lithium lithium secondary battery, and the DC / DC converter 21 is connected to the output side.

  The electric power generated in the fuel cell 90 is supplied to the secondary battery 91 by the DC / DC converter 21, and the electric power output from the DC / DC converter 21 is supplied to the inverter circuit 31 to drive the vehicle drive motor 41. .

  At this time, the total ECU 61 calculates the required power to the inverter circuit 31 based on the accelerator opening of the electric vehicle detected by the accelerator sensor. The inverter ECU 81 controls the inverter circuit 31 based on the calculated supply power, and controls the required power to be supplied to the vehicle drive motor 41 via the inverter circuit 31. The total ECU 61 controls the fuel cell 90 according to the supply state of hydrogen gas and air with respect to the power supplied to the inverter circuit 31. When the electric power from the fuel cell 90 alone cannot be covered, the general ECU 61 transmits a control signal to the converter ECU 71, and the converter ECU 71 controls the DC / DC converter 21. Output from the secondary battery 91.

  Further, the inverter circuit 31 is controlled by the inverter ECU 81 to output power from the fuel cell 90, power output from the secondary battery 91 via the DC / DC converter 21, or power output from both batteries. The input DC power is converted into AC power and supplied to the vehicle drive motor 41.

  The voltage detection sensor 51 is a sensor that detects a voltage value output from the fuel cell 90 or a voltage value of a voltage output from the secondary battery 91 via the DC / DC converter 21. The detected voltage value detected by the voltage detection sensor 51 is an analog signal and is transmitted to the general ECU 61 via the analog communication line 111. The detection voltage value of the analog signal received by the general ECU 61 is transmitted as an analog signal to the converter ECU 71 via the analog communication line 101 as in the first embodiment, and the converter ECU 71 is based on the received detection voltage value. By correcting and controlling the DC / DC converter 21, electric power is supplied according to a load request for the vehicle drive motor. Furthermore, the detected voltage value of the analog signal received by the general ECU 61 is also transmitted as an analog signal to the inverter ECU 81 via the analog communication line 101, and the inverter ECU 81 receives the detected voltage value from the inverter circuit 31 based on the received detected voltage value. Controls the amount of current output.

  However, as described in the first embodiment, the total ECU 61 simply transmits the detected voltage value received as an analog signal from the voltage detection sensor 51 to the converter ECU 71 and the inverter ECU 81 as an analog signal, and the analog signal indicates the analog voltage. If converter ECU 71 or inverter ECU 81 performs correction control based on the detected voltage value, desired power may not be supplied to the drive motor due to the influence of a voltage drop on the analog communication line.

  For example, when converter ECU 71 recognizes a detection voltage value that is lower than the detection voltage value actually detected by voltage detection sensor 51, the following occurs.

  The integrated ECU 61 calculates a value of required power to be input to the inverter circuit 31 based on the accelerator opening detected by the accelerator sensor. Based on the calculated required power, the total ECU 61 calculates a voltage value of the voltage to be output from the DC / DC converter 21 as a supply voltage value, and transmits it to the converter ECU 71. Converter ECU 71 controls DC / DC converter 21 based on the received supply voltage value, and causes DC / DC converter 21 to output a desired supply voltage.

  Thereafter, converter ECU 71 receives the detected voltage value of the voltage input to inverter circuit 31 detected by voltage detection sensor 51 as an analog signal via integrated ECU 61 for feedback control. The DC / DC converter 21 is corrected and controlled based on a comparison between the received detection voltage value and the supply voltage value to be output. That is, if the detected voltage value is lower than the supply voltage value, correction control is performed to increase the output voltage from the DC / DC converter 21. Conversely, if the detected voltage value is higher than the supply voltage value, the DC / DC converter is corrected. Correction control is performed so that the output voltage from 21 is lowered.

  By the way, the electric power input to the inverter circuit 31 and the voltage value of the output voltage of the DC / DC converter 21 have a relationship as shown in a graph shown in FIG. That is, the higher the required power, the DC / DC converter is controlled to lower the voltage value of the voltage input to the inverter circuit 31. Conversely, the lower the required power, the higher the voltage value. What is necessary is just to control a DC / DC converter so that it may become.

  Under such a relationship, the converter ECU 71 detects the detected voltage value received by the voltage detection sensor 51 through the general ECU 61 due to the influence of the voltage drop of the communication line (FIG. 8). : A) lower than (A) (FIG. 8: B), converter ECU 71 misrecognizes that more power is output than the required power calculated based on the accelerator opening, and from DC / DC converter 21 Correction control is performed to increase the output voltage. Then, in practice, the detected voltage value output as a result of the correction control is higher than the detected voltage value recognized by converter ECU 71, and as a result, the output power is reduced ( FIG. 8: C). Therefore, there is a problem that desired electric power cannot be supplied to the vehicle drive motor, resulting in a reduction in fuel consumption.

  Further, the inverter ECU 31 controls the amount of current output from the inverter circuit 31 based on the detection voltage detected by the voltage detection sensor. At this time, similarly to the above, if the detection voltage recognized by the inverter ECU 31 is lower than the actual voltage due to the influence of the voltage drop of the communication line, the amount of current output from the inverter circuit 31 is equal to the recognition error. Just get more. Therefore, as a result, the amount of current input to the vehicle drive motor 41 increases, and the power consumption and output torque of the vehicle drive motor 41 increase. In addition, the overcurrent may cause damage to the inverter circuit 31 and the vehicle drive motor 41.

  Further, the performance of the fuel cell varies depending on the fuel cell. Therefore, in the vehicle control system, the output power of the fuel cell is controlled based on the performance of the fuel cell. As a method for specifying the performance of the fuel cell, for example, the value of the output current of the fuel cell and the value of the output voltage are detected by a sensor, and based on the IV characteristics as shown in FIG. There is a method for specifying the performance of the fuel cell. In FIG. 9, the X axis is the sensor current value when the current output from the fuel cell is detected by the current detection sensor, and the Y axis is the voltage when the voltage output from the fuel cell is detected by the voltage detection sensor. It is a voltage value. Thus, even with the same current value, it can be seen that a fuel cell with good performance has a higher output voltage (FIG. 9: D) and a fuel cell with poor performance has a lower output voltage (FIG. 9: E). .

  By the way, the vehicle control system according to the present embodiment has a system configuration in which the general ECU that controls the fuel cell directly receives the detection voltage value from the voltage detection sensor 51 as an analog signal. However, a separate fuel cell ECU for controlling the fuel cell is provided, and the fuel cell ECU receives the detected voltage value from the general ECU via the communication line, and specifies the performance of the fuel cell based on the received detected voltage value. In some cases, the output power of the fuel cell is controlled based on the specified performance. In this case, as described above, the fuel cell ECU may recognize the detection voltage value lower than the actual detection voltage value due to the influence of the voltage drop of the communication line. Then, since the fuel cell ECU specifies the performance of the fuel cell based on the low-recognized detection voltage value and the current value, the fuel cell ECU is specified as a fuel cell having a lower performance than the actual fuel cell performance. . And fuel cell ECU will control the output electric power of the fuel cell based on the specified low performance, and it will become impossible to fully demonstrate the performance of the fuel cell.

  As described above, in a vehicle control system that drives an electric vehicle using a fuel cell, each ECU uses a voltage value used as a control parameter via a communication line such as a wire harness as an analog communication. When transmitting / receiving data, an error occurs between the voltage value detected by the voltage detection sensor and the voltage value recognized by the ECU due to the voltage drop of the communication line, and the desired power is supplied to the vehicle drive motor. It may not be possible or it may cause a reduction in fuel consumption.

  Therefore, in this embodiment, each ECU receives a detection voltage value to be used as a control parameter in advance as an analog signal and a digital signal before performing correction control, and a digital signal that is less affected by a voltage drop of the communication line. The correction value of the detection voltage value received as an analog signal is calculated on the basis of the detection voltage value received in (1). Each ECU performs actual correction control based on the detected voltage value of the analog signal corrected by the correction value. As a result, an error occurs between the voltage value detected by the voltage detection sensor and the voltage value recognized by the ECU due to the voltage drop of the communication line, and the desired power cannot be supplied to the vehicle drive motor. Or reducing the fuel consumption.

  Furthermore, this embodiment will be described in detail based on the flowchart shown in FIG. In FIG. 10, first, the general ECU 61 transmits the detection voltage value received from the voltage detection sensor 51 as an analog signal to the converter ECU 71 and the inverter ECU 81 via the analog communication line 101 as an analog signal, and also receives the detected detection. The voltage value is converted into a digital signal and transmitted to the converter ECU 71 and the inverter ECU 81 via the digital communication line 121 (S201). Converter ECU 71 and inverter ECU 81 determine the detected voltage value received as a digital signal that is less affected by a voltage drop or the like as the reference detected voltage value, and calculate the difference between the detected reference voltage value and the detected voltage value received as an analog signal. (S202). The calculation result is stored as a correction value for the detected voltage value of the analog signal in a memory provided inside or outside of converter ECU 71 and inverter ECU 81 (S203).

  The timing for calculating the correction value of the detection voltage value is preferably when the voltage detected by the voltage detection sensor 51 is stable. Therefore, for example, it is performed when the vehicle control system is at a constant voltage during preparation for activation. Here, in preparation for starting, as shown in FIG. 11 showing the relationship between time and the voltage on the output side of the fuel cell, hydrogen is supplied from a hydrogen tank, and air as a gas containing oxygen is supplied from a blower. In order to start power generation, it means a period during which the voltage on the output side of the fuel cell (voltage on the output side of the DC / DC converter) is kept constant.

  Then, after calculating the correction value, converter ECU 71 executes a process as shown in the flowchart of FIG. In FIG. 12, the general ECU 61 determines the output voltage value to be output from the DC / DC converter 21 to the inverter circuit 31 based on the accelerator opening detected by an accelerator sensor (not shown). (S211). Then, the total ECU 61 transmits the calculated supply voltage value to the converter ECU 71 as an analog signal via the analog communication line 101 (S212). Converter ECU 71 receives the analog signal indicating the supply voltage value, and controls DC / DC converter 21 based on the supply voltage value indicated by the analog signal (S213). The DC / DC converter 21 is controlled by the converter ECU 71 to convert the voltage value of the voltage output from the secondary battery into a supply voltage value and output it (S214).

  Thereafter, the general ECU 61 receives the voltage value of the voltage input to the inverter circuit 31 detected by the voltage detection sensor 51 as an analog signal via the communication line 111 (S215). The total ECU 61 transmits the received detection voltage value to the inverter ECU 81 and the converter ECU 71 as analog signals via the communication line 101 (S216).

  Inverter ECU 81 and converter ECU 71 each correct the detected voltage value received as an analog signal with the stored correction value (S217). Specifically, if the detected voltage value received by the analog signal is smaller than the detected voltage value received by the digital signal, the correction is performed by adding the stored correction value to the detected voltage value indicated by the received analog signal. On the contrary, if it is larger, correction is performed by subtracting the stored correction value.

  Then, converter ECU 71 and inverter ECU 81 perform the following processing based on the corrected detection voltage values, respectively.

  First, the processing flow of feedback control of converter ECU 71 will be described with reference to FIG. Converter ECU 71 calculates the difference between the corrected detected voltage value and the supply voltage value (S221). Further, it is determined whether or not the calculated difference exceeds a predetermined allowable error range (S222). If the determined difference exceeds the predetermined allowable error range, converter ECU 71 then continues to supply voltage. It is determined whether or not the corrected detection voltage value is higher than the value (S223). As a result of the determination, if the corrected detection voltage value is lower than the supply voltage value, the DC / DC converter 21 is corrected and controlled to increase the voltage output from the DC / DC converter 21 (S224). If the detected voltage value is higher than the supply voltage value, the DC / DC converter 21 is corrected and controlled to lower the voltage output from the DC / DC converter 20 (S225).

  On the other hand, the inverter ECU 81 controls the amount of current output from the inverter circuit 31 based on the corrected detected voltage value.

  As a result, by performing communication between ECUs with analog signals and performing correction control, not only can communication delay be suppressed, but the detected voltage value received with analog signals is affected by the voltage drop of the communication line, etc. Even if an error occurs, it is corrected with a correction value calculated in advance based on the detected voltage value received with a digital signal that is less affected by the voltage drop of the communication line, etc., so that the influence of the voltage drop of the communication line is suppressed. The desired electric power can be supplied to the vehicle drive motor.

  Further, the converter ECU 71 recognizes the detected voltage value received via the general ECU 61 lower than the detected voltage value actually detected by the voltage detection sensor 51 due to the influence of the voltage drop of the communication line, etc. Therefore, it is possible to prevent a reduction in fuel consumption due to a decrease in the electric power to be supplied, and a desired electric power cannot be supplied to the vehicle drive motor.

  Further, the inverter ECU 81 recognizes the detected voltage value received via the general ECU 61 lower than the detected voltage value actually detected by the voltage detection sensor 51 due to the influence of the voltage drop of the communication line, etc. The amount of current output from the circuit 31 increases more than the assumed amount of current, leading to overcurrent damage to the inverter circuit 31 and the vehicle drive motor 41, increasing motor power consumption, and overoutput torque of the motor. Can be prevented.

  In addition, when the fuel cell ECU that controls the fuel cell receives the detected voltage value from another ECU as an analog signal and specifies the performance of the fuel cell based on the detected voltage value, the detected voltage of the digital signal By correcting the detection voltage value of the analog signal based on the value, the fuel cell ECU sets the detection voltage value lower than the detection voltage value actually detected by the voltage detection sensor 51 due to the influence of the voltage drop of the communication line. Recognizing and preventing the fuel cell from being identified as a fuel cell having a performance lower than that of the actual fuel cell. Accordingly, it is possible to prevent the fuel cell ECU from controlling the output power of the fuel cell based on the low performance and not sufficiently exhibiting the performance of the fuel cell.

It is a system block diagram of the conventional vehicle control system. In the conventional vehicle control system, it is the flowchart figure which showed the process for supplying desired electric power from a power supply to a vehicle drive motor by controlling a DC / DC converter based on an accelerator opening. It is the flowchart figure which showed the flow in which converter ECU performs feedback control of a DC / DC converter based on the voltage value of the voltage which the voltage detection sensor detected in the conventional vehicle control system. 1 is a system configuration diagram of a vehicle control system in Embodiment 1. FIG. In Embodiment 1, it is a flowchart figure which shows the flow in which converter ECU calculates the correction value of the detected voltage value received with the analog signal. In Embodiment 1, it is the flowchart figure which showed the flow which correct | amends the detection voltage received with the analog signal based on the memorize | stored correction value, and converter ECU performs feedback control of a DC / DC converter. It is a system block diagram of the control system for vehicles in Embodiment 2. It is a graph which shows the relationship between the required electric power requested | required of a fuel cell at the time of a vehicle drive motor drive, and the detection voltage value required for the required electric power. It is a graph which shows the IV characteristic utilized in order to specify the performance of a fuel cell. In Embodiment 2, converter ECU and inverter ECU are flowchart figures which show the flow which calculates the correction value of the detected voltage value received with the analog signal. It is a figure which shows the relationship between time and the voltage of the output side of a fuel cell. In Embodiment 2, it is a flowchart figure which shows the flow until inverter ECU and converter ECU each correct | amend the detection voltage value received with the analog signal with the memorize | stored correction value. In Embodiment 2, it is the flowchart figure which showed the flow which correct | amends the detection voltage received with the analog signal based on the memorize | stored correction value, and converter ECU performs feedback control of a DC / DC converter. It is a system block diagram of the conventional vehicle control system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Electronic control device, 2 Power supply device, 3, 20, 21 DC / DC converter, 4, 30, 31 Inverter circuit, 5 Electric motor, 6, 50, 51 Voltage detection sensor, 10 Power supply, 40, 41 Vehicle drive motor, 90 Fuel cell, 91 Secondary battery, 100, 101, 110, 111 Analog communication line, 120, 121 Digital communication line, 60, 61 General ECU, 70, 71 Converter ECU, 80, 81 Inverter ECU.

Claims (5)

A power supply device having a converter on the output side is connected to a load device having a vehicle drive motor, and a converter control device is provided for controlling the converter in accordance with a supply voltage value calculated based on a required load from the load device. In the vehicle control system for driving an electric vehicle by supplying electric power from the power supply device to the load device and driving the vehicle drive motor,
Receiving means for receiving the detected voltage value transmitted from the detecting device for detecting the voltage value of the voltage to the vehicle drive motor supplied from the power supply device as an analog signal via the communication line, and receiving from the detecting device An analog signal transmitting means for transmitting the analog signal indicating the detected voltage value as an analog signal; and a digital signal transmitting means for converting the analog signal indicating the detected voltage value received from the detecting device into a digital signal and outputting the digital signal. A sensing voltage value transmission device comprising:
The converter control device
Analog signal receiving means for receiving the detected voltage value transmitted as an analog signal from the detected voltage value transmitting device via a communication line;
A digital signal receiving means for receiving the detected voltage value transmitted as a digital signal from the detected voltage value transmitting device via a communication line;
A detection voltage value correcting unit that corrects the detection voltage value indicated by the analog signal based on a comparison between the detection voltage value indicated by the received analog signal and the detection voltage value indicated by the received digital signal;
Correction control means for correcting and controlling the converter based on a comparison between the detected voltage value of the analog signal corrected by the detected voltage value correcting means and the supply voltage value;
A vehicle control system comprising: A power supply device comprising a first power supply provided with a fuel cell and a second power supply provided with a converter on the output side of the secondary battery connected in parallel to a load device provided with a vehicle drive motor, the load device A converter control device that controls the converter in accordance with a supply voltage value calculated based on a required load from the first power source and controls an output from the first power source, and the load from the first power source and / or the second power source. In a vehicle control system for driving an electric vehicle by supplying electric power to the device and driving the vehicle drive motor,
Receiving means for receiving the detected voltage value transmitted from the detecting device that detects the voltage value of the voltage supplied to the load device from the power supply device as an analog signal via a communication line, and the received from the detecting device An analog signal transmitting means for transmitting an analog signal indicating the detected voltage value as an analog signal; and a digital signal transmitting means for converting the analog signal indicating the detected voltage value received from the detecting device into a digital signal and outputting the digital signal. Provided with a detection voltage value transmission device
The converter control device
Analog signal receiving means for receiving the detected voltage value transmitted as an analog signal from the detected voltage value transmitting device via a communication line;
A digital signal receiving means for receiving the detected voltage value transmitted as a digital signal from the detected voltage value transmitting device via a communication line;
Detection voltage value correcting means for correcting the detection voltage value indicated by the analog signal based on a comparison between the detection voltage value indicated by the received analog signal and the detection voltage value indicated by the received digital signal;
Correction control means for correcting and controlling the converter based on a comparison between the detected voltage value of the analog signal corrected by the detected voltage value correcting means and the supply voltage value;
A vehicle control system comprising: The vehicle control system according to claim 1 or 2,
The load device is:
An inverter that converts a direct current output from the power supply device into an alternating current;
By controlling the inverter, an inverter control device that controls the current output from the inverter and input to the vehicle drive motor;
With
The inverter control device
Analog signal receiving means for receiving the detected voltage value transmitted as an analog signal from the detected voltage value transmitting device via a communication line;
A digital signal receiving means for receiving the detected voltage value transmitted as a digital signal from the detected voltage value transmitting device via a communication line;
A detection voltage value correcting unit that corrects the detection voltage value indicated by the analog signal based on a comparison between the detection voltage value indicated by the received analog signal and the detection voltage value indicated by the received digital signal;
Current correction control means for correcting and controlling the output current from the inverter based on the detected voltage value of the analog signal corrected by the detected voltage value correcting means;
A vehicle control system comprising: A power supply device having a converter on the output side is connected to a load device having a vehicle drive motor, and the converter control device controls the converter according to a supply voltage value calculated based on a required load from the load device. In the vehicle control method for driving an electric vehicle by supplying electric power from the power supply device to the load device and driving the vehicle drive motor,
A receiving step of receiving a detection voltage value transmitted from a detection device that detects a voltage value of the voltage to the vehicle drive motor supplied from the power supply device as an analog signal via a communication line;
An analog signal indicating the detected voltage value received from the detection device, an analog signal transmission step of transmitting an analog signal;
A digital signal transmitting step of converting the analog signal indicating the detection voltage value received from the detection device into a digital signal and outputting the digital signal;
In the analog signal transmission step, the detection voltage value transmitted as an analog signal, the converter control device receives an analog signal reception step via a communication line,
In the digital signal transmission step, the detection voltage value transmitted as a digital signal is received by the converter control device via a communication line.
The converter control device corrects the detection voltage value indicated by the analog signal based on the comparison between the detection voltage value indicated by the received analog signal and the detection voltage value indicated by the received digital signal. A correction process;
A correction control step in which the converter control device corrects and controls the converter based on a comparison between the detection voltage value of the analog signal corrected in the detection voltage value correction step and the supply voltage value;
The vehicle control method characterized by including. A power supply device having a converter on the output side is connected to a load device having a vehicle drive motor, and the converter control device controls the converter according to a supply voltage value calculated based on a required load from the load device. In the vehicle control program for driving the electric vehicle by supplying electric power from the power supply device to the load device and driving the vehicle drive motor,
A reception step of receiving a detection voltage value transmitted from a detection device that detects a voltage value of the voltage supplied to the vehicle drive motor supplied from the power supply device as an analog signal via a communication line;
Analog signal indicating the detected voltage value received from the detection device, an analog signal transmission process step of transmitting as an analog signal,
A digital signal transmission step of converting the analog signal indicating the detection voltage value received from the detection device into a digital signal and outputting the digital signal;
In the analog signal transmission step, an analog signal reception step in which the converter control device receives the detected voltage value transmitted as an analog signal via a communication line;
In the digital signal transmitting step, the detected voltage value transmitted as a digital signal is received by the converter control device via a communication line.
The detection voltage value that the converter control device corrects the detection voltage value indicated by the analog signal based on the comparison between the detection voltage value indicated by the received analog signal and the detection voltage value indicated by the received digital signal. A correction step;
A correction control step for correcting and controlling the converter based on a comparison between the detected voltage value of the analog signal corrected in the detected voltage value correcting step and the supply voltage value;
Is a vehicle control program that causes a computer to execute.

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