JP7559545B2 - Apparatus and method for determining abnormality of electrical equipment - Google Patents

Description

The present invention relates to an electrical equipment abnormality determination device and method for determining abnormalities in electrical equipment installed in a vehicle.

Conventionally, Patent Document 1 discloses a vehicle battery monitoring device that monitors a vehicle battery. The vehicle battery monitoring device disclosed in Patent Document 1 measures the dark current value of the vehicle battery, and determines that an abnormality exists if the measured dark current value is equal to or greater than a threshold value.

JP 2007-237868 A

However, there was a problem in that even if it was possible to detect the occurrence of an abnormality by simply comparing the dark current value with a threshold value, it was not possible to identify which electrical equipment had the abnormality. In particular, in recent years, as the number of electrical equipment installed in vehicles has increased, it has become difficult to identify which electrical equipment has an abnormality.

Therefore, the present invention has been proposed in consideration of the above-mentioned circumstances, and aims to provide an electrical equipment abnormality determination device and method that can identify an electrical equipment that is experiencing an abnormality among the electrical equipment installed in a vehicle.

In order to solve the above-mentioned problems, an electrical equipment abnormality determination device and method according to one aspect of the present invention acquires a power supply current of a vehicle and decomposes the current waveform of the acquired power supply current into current waveforms for each electrical equipment. In addition, a reference current waveform that records the current waveform when the electrical equipment is operating normally is stored in a memory unit. Then, a command signal for operating the electrical equipment is acquired to identify the electrical equipment in an operating state, and the reference current waveform of the electrical equipment identified as being in an operating state is compared with the decomposed current waveform to determine whether they match, and if they do not match, it is determined that the electrical equipment is abnormal.

According to the present invention, it is possible to identify the electrical equipment in which an abnormality is occurring among the electrical equipment installed in the vehicle.

FIG. 1 is a block diagram showing the configuration of an electrical equipment abnormality determination device according to a first embodiment of the present invention. FIG. 2 is a diagram for explaining a method for decomposing a current waveform by the electrical equipment abnormality determination device according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining the difference in current waveform between normal and abnormal states determined by the electrical equipment abnormality determination device according to the first embodiment of the present invention. FIG. 4 is a flowchart showing a processing procedure of the electrical equipment abnormality determination process performed by the electrical equipment abnormality determination device according to the first embodiment of the present invention. FIG. 5 is a timing chart for explaining the timing at which the electrical equipment abnormality determination device according to the first embodiment of the present invention determines whether or not an abnormality has occurred in an electrical equipment. FIG. 6 is a diagram showing a current waveform when an abnormality is determined by the electrical equipment abnormality determination device according to the first embodiment of the present invention. FIG. 7 is a diagram showing a current waveform when an abnormality is determined by the electrical equipment abnormality determination device according to the first embodiment of the present invention. FIG. 8 is a diagram for explaining a method of determining an abnormality in an electrical component for which an abnormality is determined by the electrical component abnormality determination device according to the first embodiment of the present invention when the electrical component is an LED. FIG. 9 is a diagram showing a current waveform of a test current that is applied to an electrical component by an electrical component abnormality determination device according to the second embodiment of the present invention. FIG. 10 is a diagram showing a current waveform of a test current that is applied to an electrical component by an electrical component abnormality determination device according to the second embodiment of the present invention. FIG. 11 is a diagram showing a current waveform of a test current that is applied to an electrical component by the electrical component abnormality determination device according to the second embodiment of the present invention. FIG. 12 is a diagram for explaining a method of determining whether an abnormality exists in an electrical component for which an abnormality is determined by the electrical component abnormality determination device according to the second embodiment of the present invention when the electrical component is a speaker. FIG. 13 is a flowchart showing the procedure of an electrical equipment abnormality determination process performed by the electrical equipment abnormality determination device according to the second embodiment of the present invention.

[First embodiment]
A first embodiment of the present invention will now be described with reference to the drawings. In the description of the drawings, the same parts are given the same reference numerals and detailed description will be omitted.

[Configuration of the electrical equipment abnormality determination device]
Fig. 1 is a block diagram showing the configuration of an electrical equipment abnormality determination device according to the present embodiment. As shown in Fig. 1, the electrical equipment abnormality determination device 1 according to the present embodiment is a device for determining abnormalities in electrical equipment mounted on a vehicle, and is connected to a current sensor 3 that measures a power supply current of the vehicle, and ECUs 5a-5c that control electrical equipment 7a-7d.

The current sensor 3 is a sensor that measures the current value of the power supply current output from the vehicle battery, and the measured current value is output to the electrical equipment abnormality determination device 1.

The ECUs (Electronic Control Units) 5a-5c output command signals to operate the electrical components 7a-7d in response to operation signals input by the vehicle occupants or control signals input from the vehicle controller. The ECUs 5a-5c also transmit the output command signals to the electrical component abnormality determination device 1 via a communication line such as a CAN-BUS (Controller Area Network-BUS) or Ethernet.

The electrical components 7a-7d are electrical components installed in the vehicle, such as car audio, headlights, air conditioners, and power windows. Among the electrical components 7a-7d, the electrical components 7a, 7c, and 7d are operated by receiving command signals from the ECUs 5a and 5c. On the other hand, the electrical component 7b is operated by the relay 9 being turned on and off by a command signal from the ECU 5b.

As shown in FIG. 1, the electrical equipment abnormality determination device 1 includes a power supply current acquisition unit 11, a waveform decomposition unit 13, a memory unit 15, a communication unit 17, an electrical equipment identification unit 19, and an abnormality determination unit 21.

The electrical equipment abnormality determination device 1 may be located anywhere in the vehicle, but is preferably provided in a relay box. The vehicle's relay box is configured to receive the current value of the power supply current and command signals from ECUs 5a-5c in advance. By providing the electrical equipment abnormality determination device 1 in the relay box, it becomes possible to obtain the necessary information without the need for additional wiring or communication.

The power supply current acquisition unit 11 is connected to the current sensor 3, and acquires the current value and current waveform of the power supply current output from the vehicle battery. In particular, the power supply current acquisition unit 11 determines whether or not a command signal has been output from the ECUs 5a-5c, and acquires the power supply current from the current sensor 3 when it determines that a command signal has been output.

The waveform decomposition unit 13 decomposes the power supply current waveform acquired by the power supply current acquisition unit 11 into current waveforms for each of the electrical components 7a-7d. For example, as shown in FIG. 2, the power supply current waveform 30 acquired from the current sensor 3 is decomposed into current waveforms for each of the electrical components currently in operation using a method such as fast Fourier transform. In FIG. 2, it is decomposed into three current waveforms 32, 34, and 36.

The memory unit 15 stores a reference current waveform that records the current waveform when the electrical equipment is operating normally. When the electrical equipment is operating normally, each electrical equipment is driven by its own unique current waveform. Therefore, the current waveform when the electrical equipment is operating normally is recorded in advance and stored in the memory unit 15 as the reference current waveform.

The communication unit 17 communicates with each part of the vehicle via the vehicle's CAN-BUS, Ethernet, etc. In particular, the communication unit 17 receives command signals from the ECUs 5a-5c and outputs them to the power supply current acquisition unit 11 and the electrical equipment identification unit 19. Note that if the electrical equipment abnormality determination device 1 is placed in a relay box, it is possible to use the communication device that is already installed in the relay box, so there is no need to provide the communication unit 17. This makes it possible to reduce the cost of installing the communication unit 17.

The electrical equipment identification unit 19 acquires a command signal for operating the electrical equipment via the communication unit 17, and identifies the electrical equipment in an operating state from among the electrical equipment 7a-7d. For example, when a command signal is acquired from the ECU 5a, it identifies the electrical equipment 7a as being in an operating state. When a command signal is acquired from the ECU 5c, it identifies whether the command signal is for the electrical equipment 7c or the electrical equipment 7d, and identifies which electrical equipment is in an operating state.

The abnormality determination unit 21 acquires from the memory unit 15 the reference current waveform of the electrical equipment identified by the electrical equipment identification unit 19 as being in an operating state, and compares the acquired reference current waveform with the current waveform decomposed by the waveform decomposition unit 13. Then, it determines whether the acquired reference current waveform matches the decomposed current waveform, and if they match, it determines that the electrical equipment is normal, and if they do not match, it determines that the electrical equipment is abnormal.

For example, there is a difference between the current waveform when the door speaker, which is an electrical device, is connected normally and the current waveform when the door speaker is disconnected, as shown in Figure 3. Therefore, the normal current waveform in Figure 3 is stored as a reference current waveform, and if a current waveform different from the reference current waveform in Figure 3 when an abnormality occurs is obtained from the power supply current, the abnormality determination unit 21 determines that an abnormality has occurred.

The electrical equipment abnormality determination device 1 is a controller composed of general-purpose electronic circuits including a microcomputer, a microprocessor, and a CPU, and peripheral devices such as a memory, and is installed with a computer program for executing the electrical equipment abnormality determination process. Each function of the electrical equipment abnormality determination device 1 can be implemented by one or more processing circuits. The processing circuit includes, for example, a programmed processing device including an electric circuit, and also includes devices such as application specific integrated circuits (ASICs) and conventional circuit components arranged to perform the functions described in the embodiments.

[Electrical equipment abnormality determination process]
Next, an explanation will be given of the electrical equipment abnormality determination process executed by the electrical equipment abnormality determination device 1 according to this embodiment. Fig. 4 is a flowchart showing the procedure of the electrical equipment abnormality determination process executed by the electrical equipment abnormality determination device 1 according to this embodiment. The electrical equipment abnormality determination process shown in Fig. 4 starts when the power supply of the vehicle is turned ON.

As shown in FIG. 4, in step S110, the power supply current acquisition unit 11 determines whether or not a command signal has been output from the ECUs 5a-5c. When a switch for operating an electrical component is turned on by an occupant of the vehicle and an operation signal is input to the ECU, or when a control signal is input to the ECU from the vehicle controller, the ECUs 5a and 5c output a command signal to the electrical components 7a, 7c, and 7d in response to the operation signal or control signal. When the ECU 5b receives an operation signal or control signal, it outputs a command signal to the relay 9 for turning the electrical component 7b on and off. At this time, when the power supply current acquisition unit 11 acquires a command signal via the communication unit 17, it determines that a command signal has been output from the ECU, and proceeds to step S120. On the other hand, when a command signal cannot be acquired, it continues to determine whether or not a command signal has been output.

In step S120, if the power supply current acquisition unit 11 determines that a command signal has been output in step S110, it acquires the power supply current from the current sensor 3. When a command signal is output from the ECUs 5a-5c, the electrical components 7a-7d are turned on and a power supply current is supplied from the battery, so that the current waveform of the power supply current changes depending on the operating state of the electrical components 7a-7d. Therefore, the power supply current acquisition unit 11 acquires the power supply current from the current sensor 3 at this timing.

For example, as shown in FIG. 5, when the vehicle is powered on at time t0 and the navigation device, which is one of the electrical components, is started, the power supply current acquisition unit 11 acquires the power supply current for a predetermined time from time t0. Similarly, when the air conditioner is started at time t1, the power supply current acquisition unit 11 acquires the power supply current for a predetermined time from time t1. Thereafter, when each electrical component is started from time t2 to t9, the power supply current acquisition unit 11 acquires the power supply current at that timing.

In addition, the electrical equipment may be constantly monitored to determine abnormalities, not just when the electrical equipment is activated. In this case, the power supply current is acquired not only when a command signal is output from the ECU, but also when the command signal changes. For example, if the electrical equipment is power steering, the power supply current is acquired every time the steering angle of the steering wheel changes. In FIG. 5, the steering angle changes at times t4, t6, and t8, so the power supply current acquisition unit 11 acquires the power supply current at these times. In this case, a reference current waveform is recorded for each steering angle of the steering wheel and stored in the memory unit 15.

In step S130, the waveform decomposition unit 13 decomposes the current waveform of the power supply current acquired in step S120 into current waveforms for each electrical component. Since the power supply current is supplied to multiple electrical components, the current waveform 30 of the power supply current is decomposed into current waveforms 32, 34, and 36 for each electrical component, as shown in FIG. 2, using a technique such as fast Fourier transform.

In step S140, the electrical equipment identification unit 19 acquires the command signal output from the ECUs 5a-5c via the communication unit 17, and identifies the electrical equipment in an operating state from among the electrical equipment 7a-7d. The electrical equipment identification unit 19 identifies the electrical equipment to which the command signal is output from the ECUs 5a-5c as the electrical equipment in an operating state.

In step S150, the abnormality determination unit 21 acquires from the memory unit 15 the reference current waveform of the electrical equipment identified in step S140 as being in an operating state, and compares the acquired reference current waveform with the current waveform decomposed in step S130.

At this time, in the case of electrical equipment that is driven by PWM (Pulse Width Modulation), such as a radiator fan or a headlight composed of LEDs, the abnormality determination unit 21 compares the period and amplitude of the current waveform as shown in FIG. 6. In addition, in the case of electrical equipment in which the current waveform has a slope at startup, the slope of the current waveform may be compared. Furthermore, in the case of electrical equipment in which the shape of the current waveform at startup is characteristic, as shown in FIG. 7, the shape of the current waveform may be compared.

In addition, when the electrical equipment is an LED (Light Emitting Diode), as shown in FIG. 8, the frequency of the current supplied from the LED driver 40 is different for each of the LEDs 42a-42d. Therefore, the abnormality determination unit 21 can distinguish and compare each of the LEDs 42a-42d based on the difference in frequency. This makes it possible to identify which LED is abnormal, even if many LEDs are used in the headlight.

Conventionally, abnormalities in electrical equipment have been judged by the ECU, but in the case of electrical equipment driven by a relay such as electrical equipment 7b, ECU 5b only turns relay 9 on and off, so it is not possible to judge abnormalities in electrical equipment 7b. However, since abnormality judgment unit 21 compares the resolved current waveform with a reference current waveform to judge abnormalities in electrical equipment 7b, it is possible to judge abnormalities even in the case of electrical equipment driven by a relay.

As a result of this comparison, the abnormality determination unit 21 determines whether the decomposed current waveform matches the reference current waveform, and if they do not match, it determines that the electrical equipment is abnormal and proceeds to step S160. On the other hand, if the decomposed current waveform matches the reference current waveform, it determines that the electrical equipment is normal, and ends the electrical equipment abnormality determination process according to this embodiment.

In step S160, the abnormality determination unit 21 identifies the electrical equipment determined to be abnormal and notifies the vehicle occupants. For example, a warning light in the vehicle cabin is turned on to notify the vehicle occupants of the abnormality in the electrical equipment. When the abnormality in the electrical equipment is notified in this manner, the electrical equipment abnormality determination process according to this embodiment is terminated.

[Effects of the First Embodiment]
As described above in detail, the electrical equipment abnormality determination device 1 according to this embodiment breaks down the current waveform of the power supply current into current waveforms for each electrical equipment, acquires a command signal for operating the electrical equipment, and identifies the electrical equipment in an operating state. Then, it compares the reference current waveform of the electrical equipment identified as being in an operating state with the broken down current waveform to determine whether they match, and if they do not match, it determines that the electrical equipment is abnormal. This makes it possible to identify the electrical equipment in which an abnormality has occurred from among the electrical equipment installed in the vehicle.

In addition, in the electrical equipment abnormality determination device 1 according to this embodiment, the electrical equipment abnormality determination device 1 is placed in a relay box mounted on the vehicle. This allows the necessary information to be obtained without new wiring or communication. In addition, since the communication device already installed in the relay box can be used, there is no need to provide a communication unit 17, which reduces costs.

[Second embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. However, in this embodiment, the configuration of an electrical equipment abnormality determination device 1 is the same as that in the first embodiment, so the same reference numerals are used and detailed description is omitted.

In the first embodiment, an abnormality was judged when the electrical equipment was started up, but some electrical equipment, such as audio equipment such as speakers, does not have a specific current waveform because music, etc. is played during normal operation. Therefore, in the present embodiment, for electrical equipment such as audio equipment, a test current is passed at a specified timing, such as when the vehicle is started up, to judge whether the electrical equipment has an abnormality.

For example, in the case where the electrical equipment 7a is an audio device, the electrical equipment 7a is preset so that a test current having a predetermined waveform pattern flows at a predetermined timing. However, in the case of audio equipment, if a test current is passed while the vehicle is running, the sound generated by the test current will be played inside the vehicle cabin, causing discomfort to the occupants. Therefore, it is preferable to pass a low-frequency test current at the same time as the opening music that is played when the vehicle is started, so that the occupants do not notice. Alternatively, the current for playing the opening music may be the test current. Furthermore, the test current may be passed in reverse phase to the left and right speakers, allowing the test current to flow without outputting sound.

Similarly, in the case of an instrument panel or display, if a test current is passed during normal operation, noise caused by the test current will be displayed on the screen, causing discomfort to the occupants. Therefore, it is preferable to pass the test current simultaneously with the opening screen that is displayed when the vehicle is started, so that the test current is passed without being noticed by the occupants. Alternatively, the current for displaying the opening screen may be used as the test current. Furthermore, the current value may be changed by turning the backlight on and off, or by repeating start-up and sleep at regular intervals, changing the current value to be used as the test current.

As another example of the test current, as shown in FIG. 9, in electrical equipment driven by AC, a waveform in which a short off time is added to the current waveform during normal operation may be used as the test current. Also, as shown in FIG. 10, a dummy current of a specified pattern may be passed before starting the electrical equipment, and then the electrical equipment is started. Furthermore, as shown in FIG. 11, in electrical equipment driven by DC, a test current of a specified pattern may be passed by starting and stopping the dummy current.

Furthermore, when the electrical equipment is audio equipment, as shown in FIG. 12, the waveform pattern of the test current supplied from the audio amplifier 50 is different for each of the speakers 52a-52d. For example, in FIG. 12, test currents having different waveform patterns A to D are supplied to the speakers 52a-52d. Therefore, since the waveform pattern of the test current differs for each speaker, the abnormality determination unit 21 can distinguish between the speakers 52a-52d and determine whether there is an abnormality. This makes it possible to identify which speaker among the multiple speakers has an abnormality.

The memory unit 15 pre-records the current waveform when the test current is passed through the electrical equipment, and stores this current waveform as the reference current waveform for the test current.

When the abnormality determination unit 21 determines whether an electrical component has an abnormality using a test current, it obtains a reference current waveform for the test current from the memory unit 15 and compares the obtained reference current waveform for the test current with the current waveform decomposed by the waveform decomposition unit 13 to determine whether they match.

[Electrical equipment abnormality determination process]
Next, the electrical equipment abnormality determination process executed by the electrical equipment abnormality determination device 1 according to this embodiment will be described. Fig. 13 is a flowchart showing the procedure of the electrical equipment abnormality determination process executed by the electrical equipment abnormality determination device 1 according to this embodiment. The electrical equipment abnormality determination process shown in Fig. 13 starts when the power supply of the vehicle is turned on. In this embodiment, the case where the electrical equipment 7a is an audio device will be described.

As shown in FIG. 13, in step S210, the power supply current acquisition unit 11 determines whether or not a command signal to pass a test current has been output from the ECU 5a. At a predetermined timing, such as when the vehicle is started, the ECU 5a outputs a command signal to pass a test current to the electrical component 7a. At this time, when the power supply current acquisition unit 11 acquires a command signal via the communication unit 17, it determines that a command signal to pass a test current has been output from the ECU, and proceeds to step S220. On the other hand, if the command signal cannot be acquired, it continues to determine whether or not a command signal has been output.

In step S220, if the power supply current acquisition unit 11 determines that a command signal to pass a test current has been output in step S210, it acquires the power supply current from the current sensor 3. When a command signal to pass a test current is output from the ECU 5a, the electrical component 7a is turned on and a test current is supplied from the battery, so that the current waveform of the power supply current changes according to the test current. Therefore, the power supply current acquisition unit 11 acquires the power supply current from the current sensor 3 at this timing.

In step S230, the waveform decomposition unit 13 decomposes the current waveform of the power supply current acquired in step S220 into current waveforms for each electrical component. Since the power supply current is supplied to multiple electrical components, the current waveform of the power supply current is decomposed into the current waveform of each electrical component using a method such as fast Fourier transform. The current waveform of electrical component 7a that is decomposed at this time is the current waveform due to the test current.

In step S240, the electrical equipment identification unit 19 acquires the command signal output from the ECU 5a via the communication unit 17 and identifies the electrical equipment 7a as the electrical equipment through which the test current flows. Since the command signal is output from the ECU 5a to the electrical equipment 7a, the electrical equipment identification unit 19 identifies the electrical equipment 7a as the electrical equipment through which the test current flows.

In step S250, the abnormality determination unit 21 acquires from the memory unit 15 a reference current waveform for the test current of the electrical equipment identified in step S240, and compares the acquired reference current waveform for the test current with the current waveform decomposed in step S230.

Then, the abnormality determination unit 21 determines whether the decomposed current waveform matches the reference current waveform for the test current, and if they do not match, it determines that the electrical equipment is abnormal and proceeds to step S260. On the other hand, if the decomposed current waveform matches the reference current waveform for the test current, it determines that the electrical equipment is normal, and ends the electrical equipment abnormality determination process according to this embodiment.

In step S260, the abnormality determination unit 21 identifies the electrical equipment determined to be abnormal and notifies the vehicle occupants. For example, a warning light in the vehicle cabin is turned on to notify the vehicle occupants of the abnormality in the electrical equipment. When the abnormality in the electrical equipment is notified in this manner, the electrical equipment abnormality determination process according to this embodiment is terminated.

[Effects of the second embodiment]
As described above in detail, in the electrical equipment abnormality determination device 1 according to the present embodiment, a test current having a predetermined waveform pattern is preset to flow to the electrical equipment at a predetermined timing. In addition, the memory unit 15 stores a reference current waveform for the test current, which records the current waveform when the test current flows. Then, the reference current waveform for the test current is compared with the decomposed current waveform to determine whether they match, and if they do not match, it is determined that the electrical equipment is abnormal. As a result, even if a power supply current having a specific current waveform does not flow through an electrical equipment during normal operation, it is possible to identify an electrical equipment having an abnormality from among the electrical equipment mounted on the vehicle.

In addition, in the electrical equipment abnormality determination device 1 according to this embodiment, if the electrical equipment is an audio device or a display device, a test current is passed when the vehicle is started. This makes it possible to determine whether there is an abnormality in the electrical equipment of the audio device or the display device using the opening music or opening screen.

The above-described embodiment is one example of the present invention. Therefore, the present invention is not limited to the above-described embodiment, and various modifications can be made to the design, etc., even if the embodiment is different from the above-described embodiment, as long as the modifications do not deviate from the technical concept of the present invention.

1 Electrical component abnormality determination device 3 Current sensor 5a-5c ECU
7a to 7d Electrical components 11 Power supply current acquisition section 13 Waveform decomposition section 15 Storage section 17 Communication section 19 Electrical component identification section 21 Abnormality determination section 40 LED driver 42a to 42d LED
50 Audio amplifier 52a to 52d Speakers

Claims (3)

An electrical equipment abnormality determination device that determines an abnormality in an electrical equipment mounted on a vehicle,
a power supply current acquisition unit for acquiring a power supply current of the vehicle;
a waveform decomposition unit that decomposes the current waveform of the power supply current acquired by the power supply current acquisition unit into current waveforms for each of the electrical components;
a storage unit that stores a reference current waveform that is a current waveform recorded when the electrical equipment is operating normally;
an electrical equipment identification unit that acquires a command signal for operating the electrical equipment and identifies an electrical equipment that is in an operating state;
an abnormality determination unit that obtains from the storage unit a reference current waveform of an electrical equipment in an operating state identified by the electrical equipment identification unit, compares the obtained reference current waveform with a current waveform decomposed by the waveform decomposition unit to determine whether they match, and determines that the electrical equipment is abnormal if they do not match ;
The electrical equipment includes a power steering system.
the power supply current acquisition unit acquires the power supply current every time a steering angle of a steering wheel changes;
The storage unit stores the reference current waveform, which is a current waveform recorded when the power steering is operating normally for each steering angle of the steering wheel,
the abnormality determination unit compares the reference current waveform for each steering angle of the steering wheel with the current waveform of the power steering decomposed by the waveform decomposition unit to determine whether or not they match, and if they do not match, determines that the power steering is abnormal.
An electrical equipment abnormality determination device comprising: An electrical equipment abnormality determination device that determines an abnormality in an electrical equipment mounted on a vehicle,
a power supply current acquisition unit for acquiring a power supply current of the vehicle;
a waveform decomposition unit that decomposes the current waveform of the power supply current acquired by the power supply current acquisition unit into current waveforms for each of the electrical components;
a storage unit that stores a reference current waveform that is a current waveform recorded when the electrical equipment is operating normally;
an electrical equipment identification unit that acquires a command signal for operating the electrical equipment and identifies an electrical equipment that is in an operating state;
an abnormality determination unit that obtains from the storage unit a reference current waveform of an electrical equipment in an operating state identified by the electrical equipment identification unit, compares the obtained reference current waveform with a current waveform decomposed by the waveform decomposition unit to determine whether they match, and determines that the electrical equipment is abnormal if they do not match ;
The electrical equipment includes a pair of left and right speakers,
The left and right speakers are preset to pass test currents of opposite phases,
the storage unit stores a reference current waveform for a test current, the reference current waveform being a record of a current waveform when the test current flows;
the power supply current acquisition unit acquires a power supply current of the vehicle when the test current flows;
The waveform decomposition unit decomposes the current waveform of the power supply current acquired by the power supply current acquisition unit into current waveforms of the left and right speakers,
The abnormality determination unit obtains a reference current waveform for the test current from the storage unit, compares the obtained reference current waveform for the test current with the current waveform decomposed by the waveform decomposition unit to determine whether or not they match, and if they do not match, determines that the left and right speakers are abnormal.
An electrical equipment abnormality determination device comprising: The electrical equipment abnormality determination device according to claim 1 or 2, characterized in that the electrical equipment abnormality determination device is disposed in a relay box mounted on the vehicle.

Images