JP2009298220A - System and method for detecting electric leak - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric leak detection system and an electric leak detection method capable of preventing any improper detection of electric leak or improper operation. <P>SOLUTION: The electric leak detection system for detecting electric leak of high voltage includes a plurality of electronic control units (ECU) including an electronic control unit (ECU) for controlling the high voltage, and a communication network for delivering/receiving information between the electronic control units (ECU), and executes the electric leak detecting operation when checking that any failure is not present in at least one of the electronic control units (ECU) before executing the electric leak detecting operation, and that the communication is normally performed between the electronic control units (ECU) by the communication network. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a leakage detection system and method, and is particularly suitable for use in a leakage detection system in an electric compressor for an automobile air conditioner.

  As shown in Patent Document 1, a hybrid vehicle, a fuel cell vehicle, or the like is known in which a control function is divided and assigned to a plurality of ECUs. In such a vehicle, transfer and exchange of data and information between ECUs is generally performed using serial communication such as CAN (Controller Area Network) or LIN (Local Interconnect Network).

  The hybrid vehicle includes a vehicle drive motor that is an electric motor driven by electric power, and a vehicle drive engine that is an internal combustion engine using gasoline or the like as a driving source for driving to generate driving force. Yes. From a vehicle motor during start-up and low-speed running, such as an ECU (Electronic Control Unit) that controls a vehicle drive engine, an ECU that operates a high-voltage battery, or an ECU that controls an actuator such as a motor using a high voltage The vehicle travels only with the driving force of the engine, and travels with the driving force of either the engine or the vehicle motor during normal traveling. The vehicle air conditioner includes an air conditioner unit for air conditioning the interior of the hybrid vehicle and an air conditioner ECU that constitutes the air conditioner unit. The air conditioner controls the temperature of the interior of the vehicle to be maintained at a set temperature. .

  In such hybrid vehicles, there are many cases where high-voltage batteries with a driving motor driving battery voltage of 200 V or higher are used, and it is possible to establish measures to prevent electric shocks during maintenance such as component replacement and inspection. It has become important. As an example of such a measure, a switch provided with a switch for detecting that the bonnet is opened when the hood is opened has been put into practical use. By this switch, the high voltage control ECU that controls the high voltage battery cuts off the power supply from the high voltage battery into the vehicle.

  Furthermore, in order to improve the level of electric shock prevention, there has been a demand for other shut-off means using a plurality of ECUs that handle not only the mechanical switch but also a high voltage. However, in an interruption system using communication between ECUs, if there is an abnormality in communication between ECUs and reliable control coordination between ECUs is not possible, there is a risk of erroneous detection or malfunction in leakage detection or power interruption control. .

  In particular, in the case of a compressor control ECU, upon receiving a command to “shift to leakage detection mode” from a host ECU such as a communication network control ECU, the INV-ECU is shifted to a leakage detection mode. Since the host ECU and the compressor ECU are connected via the in-vehicle network, the signal received by the compressor ECU is not always correct. If the INV-ECU shifts to the leakage detection mode even though it does not receive a signal “transition to the leakage detection mode” from the host ECU due to disturbances such as noise, the INV-ECU cannot drive the compressor, Air conditioning cannot be continued.

  Furthermore, if it is executed without confirming an abnormality in a communication network such as CAN, a high-voltage operation or failure exceeding 100 V is detected without detecting the operation status of the counterpart ECU in the detection of leakage faults performed by a plurality of ECUs in cooperation with each other. There is a risk of detection, which causes a problem that correct leakage detection cannot be performed.

JP 2007-002816 A

  In view of the above problems, the problem to be solved by the present invention is that in a leakage detection system using communication between ECUs, when a leakage detection command arrives from a host ECU, a failure exists in the ECU, It is an object of the present invention to provide a leakage detection system capable of preventing erroneous detection and malfunction of leakage detection when there is an abnormality in communication and reliable control coordination between ECUs is not possible.

The present invention employs the following technical means in order to achieve the above-mentioned problems.
According to the first aspect of the present invention, an electronic control unit (ECU) that controls a high-voltage battery, a compressor control electronic control unit (ECU) that controls an electric compressor, and an electronic control unit (ECU) that controls a communication network are provided. Including a plurality of electronic control units (ECUs), and
In the electric leakage detection system comprising a communication network for exchanging information between the plurality of electronic control units (ECUs),
Before performing the leakage detection operation, there is no failure in the compressor control electronic control unit (ECU), and the compressor control electronic control unit (ECU)
When it is confirmed that the condition that the communication by the communication network between the electronic control units (ECUs) has been normally performed is satisfied, the leakage detection operation is executed.
As a result, it is possible to prevent erroneous detection or malfunction of leakage detection when there is a failure in the ECU, or when there is an abnormality in communication between ECUs and mutual control coordination between ECUs is not possible, and reliable leakage detection And the execution of a leakage check can be performed.

According to a second aspect of the present invention, in the first aspect of the invention, the plurality of electronic control units (ECUs) further includes an electronic control unit (ECU) that controls an actuator using a high voltage. .
Thereby, similarly to the invention according to claim 1, it is possible to perform reliable leakage detection and execution of leakage inspection.

According to a third aspect of the present invention, in the first aspect of the invention, the compressor control electronic control unit (ECU) controls an electric compressor for an air conditioner in a hybrid vehicle, a fuel cell vehicle, or an electric vehicle. ECU).
Thus, similarly to the first aspect of the invention, it is possible to perform reliable leakage detection and leakage check in the electric compressor-high voltage battery system.

According to a fourth aspect of the present invention, in the first aspect of the invention, the compressor control electronic control unit (ECU) is a gateway electronic control for exchanging information between the first type communication protocol and the second type communication protocol. A unit (GW-ECU3) and an electronic control unit (INV-ECU4) for controlling the inverter motor are provided.
Thus, in the same manner as in the first aspect of the invention, a gateway function is provided in order to exchange information with a high-speed CAN bus separately from the INV-ECU 4 equipped with a photocoupler in order to achieve electrical insulation. Even in the case of a configuration including the ECU (GW-ECU 3), it is possible to perform reliable leakage detection and leakage inspection.

  According to a fifth aspect of the present invention, in the first aspect of the invention, the communication network uses a communication protocol (CAN, LIN, FLEX-RAY, MOST, or other serial communication) specified for in-vehicle use. It is characterized by being. This makes it possible to utilize a communication network originally used for communication between ECUs without preparing a dedicated communication line for detecting leakage, and to apply a system for detecting high-voltage leakage to vehicles. Easy.

  According to a sixth aspect of the present invention, in the first aspect of the invention, the plurality of electronic control units (ECUs) further include a timed timer (step S118) for forcibly cutting off the power. And As a result, even when the communication network suddenly fails and information cannot be exchanged, the power supply can be cut by itself to prevent the battery supplying the ECU from being consumed.

The invention described in claim 7 includes an electronic control unit (ECU) that controls a high-voltage battery, a compressor control electronic control unit (ECU) that controls an electric compressor, and an electronic control unit (ECU) that controls a communication network. There is no failure in the compressor control electronic control unit (ECU) before performing the step of exchanging information through the communication network between the plurality of electronic control units (ECU) including the leakage detection operation. And the compressor control electronic control unit (ECU) confirming that the condition that the communication by the communication network between the electronic control units (ECU) is normally performed is established (S200 to S203); In the step of checking, if the condition is satisfied, About leakage detection method comprising the step (S115) to the line.
As a result, it is possible to prevent erroneous detection or malfunction of leakage detection when there is a failure in the ECU, or when there is an abnormality in communication between ECUs and mutual control coordination between ECUs is not possible, and reliable leakage detection And the execution of a leakage check can be performed.

  In addition, the code | symbol attached | subjected above is an example which shows a corresponding relationship with the specific embodiment as described in embodiment mentioned later.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an overall schematic diagram showing an electric compressor system for an air conditioner. FIG. 2 is a partial detailed schematic view of FIG.
The electric compressor 1 for an air conditioner electronically controls a refrigerant compressor 6 that compresses and liquefies the vaporized refrigerant, an inverter motor 5 that drives the compressor, a refrigerant pipe 8 that is connected to the refrigerant compressor and delivers refrigerant. It consists of two ECUs, that is, an inverter control ECU 4 (hereinafter abbreviated as INV-ECU 4) and a gateway ECU 3 (hereinafter abbreviated as GW-ECU 3). The INV-ECU 4 and the GW-ECU 3 constitute a compressor control ECU.

  The INV-ECU 4 receives the high voltage (for example, 288V) 12 from the high-voltage battery 7 for the hybrid vehicle, and drives the inverter motor 5 according to the control information from the GW-ECU 3. The GW-ECU 3 receives information on the rotational speed of the inverter motor from the air conditioner ECU 16 via the CAN bus 13 and transmits the information to the INV-ECU 4 via the SCI communication 17. From the viewpoint of preventing electric shock, the GW-ECU 3 and the INV-ECU 4 are electrically insulated using a photocoupler. For this reason, since the communication speed cannot be raised to the level of CAN communication, information is exchanged in the GW-ECU 3 in order to connect the SCI communication 17 in the electric compressor 1 to the CAN bus 13 which is a vehicle network. Yes.

  The high voltage control ECU 2 mainly performs ON / OFF of whether or not to send power from the high voltage battery 7 for the hybrid vehicle by the switching signal 10, so that the motor for driving the hybrid vehicle (not shown) Control of high voltage supply to the inverter motor 5 of the system is performed. Although not described in detail in this ECU, a leakage detection sensor 9 is connected to detect the presence or absence of leakage during high voltage output.

  In this system, the network management ECU 15 notifies each ECU connected to the CAN bus 13 of an IG-Key state (which indicates an ON or OFF state of the start button) described later and a transition to the sleep mode. Or

FIG. 3 shows an overall flowchart of processing in the GW-ECU.
When the power is turned on to the GW-ECU, a power-on reset state (step S100) is entered, and a predetermined initial setting process (step S101) is executed. Here, a leak detection flag described later is cleared to zero. The power-on reset state means that each ECU including the GW-ECU has returned to the microcomputer from the reset state when the power is turned on, and the program is ready to be executed.

  In step 102, each task process such as a 2 ms process (step S103), a 10 ms process (step S104), and a 100 ms process (step S105) is executed by a time synchronization program scheduled in advance. These time synchronization processes are continuously executed until the power of the GW-ECU 3 is turned off.

FIG. 4 shows a flowchart of leakage detection in the GW-ECU. This process is programmed as a task in the 10 ms process in FIG.
When the driving driver presses the IG-Key (start button), the network management ECU recognizes this, issues a wake-up pulse to each ECU through a dedicated line, and forces the power to each ECU. It has become. At the same time that the GW-ECU 3 is activated, IG-Key information (IG-Key ON) is sent via the CAN bus. The GW-ECU 3 recognizes the IG-Key state. The state where the start button is pressed and turned ON is IG-Key ON, and when the button is pressed again and turned OFF, the state is IG-Key OFF.

  In step S110, it is confirmed whether or not the IG-Key OFF information sent from the network management ECU 15 via the CAN bus 13 has changed from ON to OFF. If the IG-Key has changed from ON to OFF, a leakage detection flag Is set to 1 (step 112). As a detection means in the case of changing from ON to OFF, it is possible to detect by holding past information 10 ms ago and comparing it with the latest information.

  Note that the leakage detection flag set in step S112 is used for SCI communication in order to drive the IGBT (insulated gate bipolar transistor) for leakage detection from the GW-ECU 3 to the INV-ECU 4 in step S115 described later. Sent out. On the other hand, by clearly indicating that the earth leakage detection operation mode is set when the earth leakage detection flag is 1, in other processes such as diagnosis (vehicle self-diagnosis function), it is possible to prevent malfunction or detection. used.

  Except when the IG-Key is changed from ON to OFF (in the case of NO), the state of the IG-Key information is checked in Step S111. At this time, if it is not OFF (IG-Key ON), the leakage detection logic does not function until the driver detects that the driver turns OFF the IG-Key and stops the vehicle, and step S119 is performed. After that, this process is exited. If it is OFF, the process proceeds to step S113. This is because when it is OFF, the leakage detection flag is already set to 1, and step S112 is unnecessary.

  Next, the leakage detection operation mode is confirmed (step S113). Here, it is provided to confirm whether the system driver is actually in a state where it can detect leakage even though the driving driver has turned off IG-Key. Details of the confirmation conditions will be described in the description of FIG.

When it is determined in step S113 that the leakage detection condition is not satisfied, the process proceeds to confirmation of the determination to shift to the sleep mode in step 117 described later.
If it is determined in step 113 that leakage detection is possible, the IGBT drive operation for leakage detection is instructed to the INV-ECU 4 via SCI communication (step S115).

Next, leakage detection inspection flag information is transmitted to the high-voltage control ECU 2 to notify permission to execute the leakage detection inspection. (Step S116)
That is, when the leakage detection inspection flag changes from 0 to 1, the execution of the leakage detection inspection is permitted by setting 1 in the timing processing loop of the high voltage control ECU 2, and the high voltage control ECU 2 sets the leakage detection sensor 9 to Uses leakage detection.

  In step S117, a sleep act (a process for checking whether or not to enter the sleep mode) is performed. This sleep act information is information that causes the network management ECU 15 to send the IG-Key information to each ECU, wait for a predetermined time (in one example, 20 minutes), and then send the ECU to the sleep mode. When the sleep act information comes, it is determined that the sleep mode can be entered.

  If the GW-ECU 3 can shift to the sleep mode in step S117, the leakage detection flag is cleared to 0 (step S119), and the process ends. If it is not possible to shift to the sleep mode, it is confirmed whether the time for forcibly turning off the power (for example, 31 minutes) has elapsed (step S118). If the time has not elapsed, nothing is done as it is. The process ends. If the time has elapsed, the leakage detection flag is cleared to 0 (step 119), and the process ends. The purpose of monitoring the forced power cut-off time is that when there is an abnormality in the CAN bus 13 or the like, the sleep act information is not received from the network management ECU 15, and the power of the GW-ECU 3 is not cut off indefinitely. This is to avoid it.

  This earth leakage detection system starts from the IG-Key OFF of the network management ECU 15 and performs an earth leakage detection judgment by the GW-ECU and an IGBT driving operation for earth leakage detection to the INV-ECU 4, and the high voltage control ECU 2 includes an earth leakage detection sensor. 9 is used to detect the presence or absence of leakage detection.

  The leakage detection inspection flag information is issued to the high voltage control ECU 2 when the GW-ECU 3 performs the leakage detection IGBT drive operation on the INV-ECU 4. After receiving the leakage detection detection flag information, the high voltage control ECU 2 performs a leakage detection inspection in the electric compressor 1 using the leakage detection sensor 9 for 3 seconds. If leakage is confirmed, the high voltage battery 7 The power supply is stopped and the main power supply of the INV-ECU 4 is immediately cut off.

  The network management ECU 15 waits for 5 seconds for the leakage detection inspection in the high-voltage control ECU 2 after transmitting the IG-Key OFF information. Regardless of the inspection result or whether or not the inspection is performed, the network management ECU 15 Then, the sleep act information is output on the CAN bus 13 to shift to the sleep mode. The GW-ECU 3 cuts the built-in power supply circuit based on information on the request for transition to the sleep mode.

FIG. 5 shows the detailed contents of “Confirmation of leakage detection operation mode” in FIG.
Here, the presence / absence of failure of the INV-ECU 4 (step S200), the presence / absence of SCI communication abnormality with the INV-ECU 4 (step S201), the presence / absence of other failure detection recorded in the GW-ECU 3 (step S202), CAN communication The presence / absence of abnormality detection (step S203) identifies whether the leakage detection condition is not established, established, or whether leakage detection is not performed due to an abnormality such as INV-ECU4.

  Next, the basic definition of abnormality / failure in steps S200, S201, S202, and S203 in FIG. 5 will be described.

1. Definition of failure of the INV-ECU 4 The INV-ECU 4 itself is in an overheated state of circuit elements such as IGBTs, malfunctions of the inverter motor 5 during the driving cycle (IG-Key On period), and other abnormalities that occur inside the ECU. When it is detected. (This abnormality is notified to the GW-ECU 3)

2. Definition of communication data abnormality that occurs in SCI communication between GW-ECU 3 and INV-ECU 4 (1) Disconnection or short circuit of communication line, malfunction due to ECU power fluctuation, CPU runaway, etc. When it is detected that a transmission / reception event no longer occurs in at least one of the two ECUs.
(2) When the GW-ECU 3 and the INV-ECU 4 recognize a communication error detected by a UART (Universal Synchronous Asynchronous Receiver Transmitter) module at the time of SCI communication, any of a parity, a framing error, and an overrun error. When the GW-ECU 3 and the INV-ECU 4 recognize a communication error by other means during SCI communication.

3. Definition of failure of the GW-ECU 3 When the GW-ECU 3 itself detects an abnormality occurring in the ECU during the driving cycle (IG-Key On period).

4). Definition of communication data error on CAN bus 13 (1) When a CAN bus off error occurs.
(2) When a failure indicating that high voltage information is no longer sent periodically from the high voltage control ECU 2 is detected.
This means that high voltage information is no longer sent by CAN communication. In this example, as an example, high voltage information is sent from the high voltage control ECU 2 every 100 ms.
(3) When it is detected from the network management ECU 15 that IG-Key information has not been sent. This indicates the time when the GW-ECU 3 recognizes that it has never received IG-Key information (whether ON or OFF) after the power-on reset.
(4) When a failure indicating that the control rotational speed information of the inverter motor 5 is not sent periodically is detected from the air conditioner ECU 16.
(5) When each ECU on the CAN bus distributes error information indicating that some failure has been detected during communication on the CAN bus.

  In the above embodiment, the CAN bus is used for the description. However, the communication between ECUs using communication protocols such as LIN, FLEX-RAY, MOST, and other serial communication is specified for all in-vehicle use. The leakage detection system described so far can be applied to any communication protocol.

1 is an overall schematic diagram showing an electric compressor system for an air conditioner. It is a detailed schematic diagram showing a part of an electric compressor system for an air conditioner. The whole flowchart of the process in GW-ECU3 is shown. The flowchart of the earth-leakage detection in GW-ECU3 is shown. The detailed content of “Confirmation of leakage detection operation mode” in FIG. 4 is shown.

Explanation of symbols

1 Electric compressor for air conditioner 3 Gateway ECU (GW-ECU)
4 Inverter control ECU (INV-ECU)
DESCRIPTION OF SYMBOLS 5 Inverter motor 6 Refrigeration compressor 7 High voltage battery for hybrid vehicles 8 Refrigeration piping 9 Leakage detection sensor 10 Switching signal 12 288V high voltage output 13 CAN bus 15 Network management ECU
16 Air conditioner ECU

Claims (7)

A plurality of electronic control units (ECU) including an electronic control unit (ECU) for controlling the high voltage battery, a compressor control electronic control unit (ECU) for controlling the electric compressor, and an electronic control unit (ECU) for controlling the communication network As well as
In the electric leakage detection system comprising a communication network for exchanging information between the plurality of electronic control units (ECUs),
Before performing the leakage detection operation, there is no failure in the compressor control electronic control unit (ECU), and the compressor control electronic control unit (ECU)
An earth leakage detection system for executing an earth leakage detection operation when it is confirmed that a condition that communication by the communication network between the electronic control units (ECUs) has been normally performed is satisfied.   The leakage detection system according to claim 1, wherein the plurality of electronic control units (ECUs) further includes an electronic control unit (ECU) that controls the actuator using a high voltage.   2. The electric leakage according to claim 1, wherein the compressor control electronic control unit (ECU) is an electronic control unit (ECU) that controls an electric compressor for an air conditioner in a hybrid vehicle, a fuel cell vehicle, or an electric vehicle. Detection system.   The compressor control electronic control unit (ECU) includes a gateway electronic control unit (GW-ECU) for exchanging information between the first type communication protocol and the second type communication protocol, and an electronic control unit for controlling the inverter motor. The leakage detection system according to claim 1, further comprising: (INV-ECU).   The leakage detection system according to claim 1, wherein the communication network uses a communication protocol defined for in-vehicle use.   The leakage detection system according to claim 1, wherein the plurality of electronic control units (ECUs) further include a time timer for forcibly cutting off the power. A plurality of electronic control units (ECU) including an electronic control unit (ECU) for controlling the high voltage battery, a compressor control electronic control unit (ECU) for controlling the electric compressor, and an electronic control unit (ECU) for controlling the communication network Sending and receiving information via the communication network,
Before executing the leakage detection operation, there is no failure in the compressor control electronic control unit (ECU), and the compressor control electronic control unit (ECU) is connected between the electronic control units (ECU). A step of confirming that a condition that the communication via the communication network has been normally performed is satisfied;
A leakage detection method comprising a step of executing a leakage detection operation when the condition is satisfied in the checking step.

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