Power System

Abstract

To determine whether a negative pole connection part is connected to a vehicle body by a connection component.SOLUTION: A power system is mounted on a vehicle and includes: a power supply device for supplying DC power to power lines; an electric load connected to the power line; and a control device for controlling the power supply device. The power lines include a positive pole side line and a negative pole side line. The negative pole side line includes: a negative pole connection part connected to a negative pole terminal of the power supply device; a vehicle body to which the electric load is connected; and a connection component for connecting the negative pole connection part to the vehicle body. The control device determines that the negative pole connection part is connected to the vehicle body by the connection component when a voltage difference between an output voltage of the power supply device and a voltage of the electric load is equal to or less than a threshold, and determines that the negative pole connection part is not connected to the vehicle body by the connection component when the voltage difference is greater than the threshold.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to power systems. [Background technology]

[0002] A conventional technology of this type has been proposed as a power supply control device for controlling power supply to an electric device that requires earth connection, which includes a pair of transformers with different winding ratios between the primary coil and the secondary coil, the two primary coils and the two secondary coils in the pair of transformers being connected in series to form a primary coil group and a secondary coil group, the primary coil group being connected in parallel to the electric device to a power supply line, the space between the two primary coils being connected to the earth wire of the electric device, and the secondary coil group being connected to a control circuit that controls power supply to the electric device (see, for example, Patent Document 1). In this power supply control device, the control circuit detects whether the electric device is earthed or not according to an induced voltage generated in the secondary coil group. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-181029 A Summary of the Invention [Problem to be solved by the invention]

[0004] The method of the power supply control device described above detects whether an electrical device is earthed based on the induced voltage generated in the secondary coil group, and cannot be applied to a DC power circuit. Therefore, in a case where a negative connection part connected to a negative terminal of a power supply device that supplies DC power is connected to a vehicle body to which an electrical load is connected by a connection part to form a negative side line, the above method cannot determine whether the negative connection part and the vehicle body are connected by the connection part. Therefore, a method capable of determining this is desired.

[0005] A main object of the power system of the present invention is to make it possible to determine whether or not a negative electrode connecting portion and a vehicle body are connected by a connecting part. [Means for solving the problem]

[0006] In order to achieve the above-mentioned main object, the power system of the present invention employs the following measures.

[0007] The power system of the present invention comprises: A power supply device for supplying DC power to a power line; an electrical load connected to the power line; A control device that controls the power supply device; A power system equipped with the above and mounted on a vehicle, The power line includes a positive line and a negative line, the negative side line includes a negative electrode connection part connected to a negative electrode terminal of the power supply device, a vehicle body to which the electric load is connected, and a connection part for connecting the negative electrode connection part and the vehicle body, When a voltage difference between an output voltage of the power supply device and a voltage of the electric load is equal to or smaller than a threshold value, the control device determines that the negative electrode connection part and the vehicle body are connected by the connection part, and when the voltage difference is larger than the threshold value, determines that the negative electrode connection part and the vehicle body are not connected by the connection part. The gist of the present invention is as follows.

[0008] In the power system of the present invention, when the voltage difference between the output voltage of the power supply device and the voltage of the electric load is equal to or less than a threshold value, it is determined that the negative electrode connection part and the vehicle body are connected by the connection part, and when the voltage difference is greater than the threshold value, it is determined that the negative electrode connection part and the vehicle body are not connected by the connection part. When the negative electrode connection part and the vehicle body are connected by the connection part and a current flows to the electric load, the current returns to the power supply device via the vehicle body, the connection part, and the negative electrode connection part. On the other hand, when the negative electrode connection part and the vehicle body are not connected by the connection part and a current flows to the electric load, the current returns to the power supply device via the vehicle body, a part other than the connection part (for example, a shield covering the positive electrode side power line and the negative electrode side power line in a power line different from the above-mentioned power line), and the negative electrode connection part. Basically, since the separate part has a higher resistance value and a higher voltage drop than the connecting part, when the negative electrode connecting part and the vehicle body are not connected by the connecting part, the voltage difference between the output voltage of the power supply device and the voltage of the electric load is larger than when the negative electrode connecting part and the vehicle body are connected by the connecting part. Therefore, by comparing this voltage difference with a threshold value, it is possible to determine whether the negative electrode connecting part and the vehicle body are connected by the connecting part.

[0009] In the power system of the present invention, the power supply device may be a DC / DC converter that reduces the power of a second power line to which a drive device for driving and an electric storage device are connected and supplies the power to the power line, and a housing of the electric storage device may be fixed to the vehicle body, and the second power line may have a second positive side line, a second negative side line, and a shield that covers the second positive side line and the second negative side line. In this configuration, when a current flows through an electric load without connecting the negative electrode connection part to the vehicle body by a connecting part, at least a part of the current returns to the power supply device via the vehicle body, the electric storage device, the shield of the second power line, and the negative electrode connection part. In order to prevent overheating of the shield, it is preferable to determine whether the negative electrode connection part is connected to the vehicle body by a connecting part.

[0010] In the power system of the present invention, the control device may operate the electric load to obtain a voltage of the electric load while controlling the electric power supply device so that the voltage of the power line becomes a target voltage. In this way, a voltage difference between the output voltage of the electric power supply device and the voltage of the electric load can be obtained.

[0011] In the power system of the present invention, when the control device determines that the negative electrode connector and the vehicle body are not connected by the connection part, the control device may limit the operation of the power supply device compared to when the control device determines that the negative electrode connector and the vehicle body are connected by the connection part. In this way, overheating of the above-mentioned separate components can be suppressed. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing an outline of the configuration of an electric vehicle 10 equipped with a power system according to an embodiment of the present invention. [Diagram 2] 2 is an explanatory diagram showing an example of the layout and electrical connection relationships of some of the components of an electric vehicle 10. FIG. [Diagram 3] 4 is a flowchart showing an example of a processing routine executed by a main ECU 70. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Next, an embodiment of the present invention will be described with reference to the accompanying drawings. EXAMPLES

[0014] 1 is a schematic diagram showing the configuration of an electric vehicle 10 equipped with a power system according to an embodiment of the present invention. As shown in the figure, the electric vehicle 10 includes a front motor 24, a front inverter 26, a front electronic control unit (hereinafter referred to as "front ECU") 27, a rear motor 34, a rear inverter 36, a rear electronic control unit (hereinafter referred to as "rear ECU") 37, a main battery 42, a battery electronic control unit (hereinafter referred to as "battery ECU") 44, a system main relay 46, a DC / DC converter 48, an auxiliary battery 52, a plurality of auxiliary machines 54, an auxiliary machine electronic control unit (hereinafter referred to as "auxiliary ECU") 56, and a main electronic control unit (hereinafter referred to as "main ECU") 70. The power system according to the embodiment mainly includes the DC / DC converter 48, the plurality of auxiliary machines 54, and the main ECU 70.

[0015] The front motor 24 is configured as, for example, a synchronous generator motor, and is connected to a front drive shaft 23 which is connected to the front wheels 20 via a front axle 21 and a front differential gear 22. A part of the front axle 21, the front differential gear 22, the front drive shaft 23, and the front motor 24 are housed in a housing 25 made of metal (for example, aluminum).

[0016] The front inverter 26 is connected to a drive system power line 40, and drives the front motor 24 by switching a plurality of switching elements. The front ECU 27 includes a microcomputer (not shown) having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports. A rotational position θmf and the like from a rotational position sensor (not shown) that detects the rotational position of the rotor of the front motor 24 is input to the front ECU 27 via an input port, and a control signal to the front inverter 26 and the like are output from the front ECU 27 via an output port. The front ECU 27 calculates the rotational speed Nmf of the front motor 24 based on the rotational position θmf of the rotor of the front motor 24 from the rotational position sensor. The front ECU 27 is connected to the main ECU 70 via the communication port so as to be able to communicate with each other. The front inverter 26 and the front ECU 27 are housed in a housing 28 made of metal (for example, aluminum).

[0017] The rear motor 34 is configured as, for example, a synchronous generator motor, and is connected to a rear drive shaft 33 which is connected to the rear wheels 30 via a rear axle 31 and a rear differential gear 32. A part of the rear axle 31, the rear differential gear 32, the rear drive shaft 33, and the rear motor 34 are housed in a housing 35 made of metal (for example, aluminum).

[0018] The rear inverter 36 is connected to a drive system power line 40, and drives the rear motor 34 by switching a plurality of switching elements. The rear ECU 37 includes a microcomputer (not shown) having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports. A rotational position θmr and the like from a rotational position sensor (not shown) that detects the rotational position of the rotor of the rear motor 34 is input to the rear ECU 37 via an input port, and a control signal and the like to the rear inverter 36 is output from the rear ECU 37 via an output port. The rear ECU 37 calculates the rotational speed Nmr of the rear motor 34 based on the rotational position θmr of the rotor of the rear motor 34 from the rotational position sensor. The rear ECU 37 is connected to the main ECU 70 via the communication port so as to be able to communicate with each other. The rear inverter 36 and the rear ECU 37 are housed in a housing 38 made of metal (for example, aluminum).

[0019] The main battery 42 is configured as, for example, a lithium ion secondary battery or a nickel hydrogen secondary battery with a rated voltage of several hundred volts, and is connected to the drive system power line 40. The battery ECU 44 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port, although not shown. The battery ECU 44 receives the voltage Vbm and the current Ibm from a voltage sensor and a current sensor that detect the voltage and current of the main battery 42 via an input port. The battery ECU 44 is connected to the main ECU 70 via the communication port so as to be able to communicate with the main battery 42. The battery ECU 44 calculates the charge ratio SOC of the main battery 42 based on the current Ibm of the main battery 42 from the current sensor. The system main relay 46 connects and disconnects the drive system power line 40 and the main battery 42. The main battery 42, the battery ECU 44, and the system main relay 46 are housed in a housing 45 made of metal (for example, aluminum).

[0020] DC / DC converter 48 steps down the power of drive system power line 40 and supplies it to auxiliary system power line 50. DC / DC converter 48 is housed in a metal (e.g., aluminum) housing 49. An auxiliary battery 52, a plurality of auxiliary machines 54, front ECU 27, rear ECU 37, battery ECU 44, auxiliary ECU 56, and main ECU 70 are connected to auxiliary system power line 50. Note that front ECU 27, rear ECU 37, battery ECU 44, auxiliary ECU 56, and main ECU 70 each have a built-in voltage sensor and are capable of detecting the voltage applied to the corresponding ECU.

[0021] The auxiliary battery 52 is configured as a lead-acid battery with a rated voltage of, for example, 12V. Examples of the multiple auxiliary devices 54 include lights, power windows, and an audio system. The auxiliary ECU 56 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports (not shown). The auxiliary ECU 56 receives a voltage Vba and a current Iba from a voltage sensor and a current sensor that detect the voltage and current of the auxiliary battery 52 via an input port. The auxiliary ECU 56 outputs control signals to the multiple auxiliary devices 54 via an output port. The auxiliary ECU 56 is connected to the main ECU 70 via the communication port so as to be able to communicate with each other. The auxiliary ECU 56 is housed in a housing 57 made of metal (for example, aluminum).

[0022] Although not shown, the main ECU 70 includes a microcomputer having a CPU, a ROM, a RAM, a flash memory, an input / output port, and a communication port. The main ECU 70 is accommodated in a housing 71 made of metal (for example, aluminum). The main ECU 70 receives an input voltage Vi from a voltage sensor 49i that detects an input voltage (voltage on the drive system power line 40 side) of the DC / DC converter 48, an output voltage Vo from a voltage sensor 49o that detects an output voltage (voltage on the auxiliary system power line 50 side) of the DC / DC converter 48, a signal from a power switch 72, and the like, via an input port. From the main ECU 70, control signals to the system main relay 46, the DC / DC converter 48, a warning light 74, and the like are connected via an output port. As described above, the main ECU 70 is communicably connected to the front ECU 27, the rear ECU 37, the battery ECU 44, and the auxiliary ECU 56 via the communication port.

[0023] FIG. 2 is an explanatory diagram showing an example of the arrangement and electrical connection relationship of some of the components of the electric vehicle 10. As shown in the figure, in a storage section at the front of the vehicle, a housing 28 housing a front inverter 26 and a front ECU 27 is fixed to the upper surface of a housing 25 housing a front motor 24 and the like by bolts or the like, a metal (e.g., aluminum) reinforcing member 80 is arranged on the upper side of the housing 28, a housing 49 housing a DC / DC converter 48 is fixed to the upper surface of the reinforcing member 80 by bolts or the like, and a housing 71 housing a main ECU 70 is fixed to the upper surface of the housing 49 by bolts or the like. The reinforcing member 80 is fixed at a position electrically insulated from a vehicle body 82 in the vehicle body. In a storage section at the center of the vehicle (e.g., a storage section below the rear seats), a housing 45 housing a main battery 42, a battery ECU 44, and a system main relay 46 is fixed to the lower surface of the vehicle body 82 by bolts or the like. The vehicle body 82 is formed by applying cationic paint or the like to a metal (e.g., iron) plate-shaped member. A metal (e.g., aluminum) earth part 84 is fixed to the vehicle body 82 by an earth bolt or the like, and this earth part 84 is also fixed to the reinforcing member 80 by a bolt or the like. As a result, the vehicle body 82 and the reinforcing member 80 are electrically connected via the earth part 84. In the housing section at the rear of the vehicle, a housing 38 that houses the rear inverter 36 and the rear ECU 37 is fixed to the upper surface of a housing 35 that houses the rear motor 34 etc.

[0024] 1 includes drive system power lines 40a, 40b, and 40c that are connected to each other within a housing 49. Each of drive system power lines 40a, 40b, and 40c includes a positive power line 41p that is an electric wire having a core wire and an insulating coating covering the core wire, a negative power line 41n that is an electric wire having a core wire and an insulating coating covering the core wire, a cylindrical shield 41s that is a metallic braided tube (braided material) that covers the positive power line 41p and the negative power line 41n, and a corrugated tube 41c that covers the shield 41s. The high-voltage side of DC / DC converter 48 is connected to front inverter 26 via drive system power line 40a, to rear inverter 36 via drive system power line 40b, and to main battery 42 via drive system power line 40c.

[0025] The low-voltage side of the DC / DC converter 48 is connected to the multiple auxiliary devices 54 and each ECU such as the auxiliary device ECU 56 via the positive-side line of the auxiliary device power line 50, and is also connected to the multiple auxiliary devices 54 and each ECU such as the auxiliary device ECU 56 via the housing 49, the housing 71, the reinforcing member 80, the earthing part 84, and the vehicle body 82. The positive-side line of the auxiliary device power line 50 is configured as an electric wire having a core wire and an insulating coating covering the core wire. In addition, the negative-side line of the auxiliary device power line 50 is configured by the housing 49, the reinforcing member 80, the earthing part 84, and the vehicle body 82. Some of the multiple auxiliary devices 54 and the auxiliary device ECU 56 are arranged close to each other at a position spaced apart from the DC / DC converter 48 to a certain extent. An earthing wire 90 for radio noise is attached to the housing 45 and the housing 25, and an earthing wire 92 is attached to the housing 45 and the housing 35.

[0026] Next, a description will be given of the operation of the electric vehicle 10 of the embodiment thus configured, in particular the operation when determining whether or not the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82. Fig. 3 is a flowchart showing an example of a processing routine executed by the main ECU 70. This routine is executed, for example, when the power switch 72 is turned on (when a command to start the system is issued).

[0027] 3 is executed, the main ECU 70 first turns on the system main relay 46 (step S100). Then, the main ECU 70 starts a predetermined drive of the DC / DC converter 48 and transmits a predetermined operation command to the auxiliary ECU 56 (step S110). In the predetermined drive of the DC / DC converter 48, a predetermined voltage Vo1 is set as the target output voltage Vo* of the DC / DC converter 48, and the DC / DC converter 48 is controlled so that the difference between the output voltage Vo of the DC / DC converter 48 from the voltage sensor 48o and the target output voltage Vo* is cancelled. As the predetermined voltage Vo1, a voltage higher than the rated voltage of the auxiliary battery 52, for example, a voltage equal to or slightly lower than the allowable output voltage, is used. When the auxiliary ECU 56 receives a specified operation command, it operates a specific high-load auxiliary among the multiple auxiliary devices 54 that is located at a position away from the DC / DC converter 48 (a position where the current path is long) and close to the auxiliary ECU 56, and detects the voltage of this specific auxiliary device using a voltage sensor not shown, and detects the voltage of the auxiliary ECU 56 using a built-in voltage sensor, and transmits it to the main ECU 70 as a load voltage Vlo.

[0028] Next, the output voltage Vo of the DC / DC converter 48 from the voltage sensor 48o and the load voltage Vlo from the auxiliary ECU 56 are input (step S120), and the predetermined drive of the DC / DC converter 48 is stopped and a predetermined operation stop command is sent to the auxiliary ECU 56 (step S110). Upon receiving the predetermined operation stop command, the auxiliary ECU 56 stops the auxiliary that is in operation among the multiple auxiliary devices 54.

[0029] Then, the load voltage Vlo is subtracted from the output voltage Vo of the DC / DC converter 48 to calculate a voltage difference ΔV (step S140), and the calculated voltage difference ΔV is compared with a threshold value ΔVref (step S150). Here, the threshold value ΔVref is a threshold value used to determine whether or not the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82. When the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82, the output current from the DC / DC converter 48 is supplied to the multiple auxiliaries 54 (including specific auxiliaries) and each ECU via the positive line of the auxiliary power line 50, and further returns to the DC / DC converter 48 via the vehicle body 82, the earth part 84, the reinforcing member 80, and the housing 49. That is, the vehicle body 82, the earth part 84, the reinforcing member 80, and the housing 49 form a negative line of the auxiliary power line 50. At this time, the resistance value of the negative line is low, and the voltage drop due to the negative line is low, so that the load voltage Vlo is high and the voltage difference ΔV is small. In contrast, when the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82, the vehicle body 82 and the reinforcing member 80 are electrically separated. At this time, the current supplied to the multiple accessories 54 and each ECU returns to the DC / DC converter 48 via, for example, the following first to third paths. The first path is a path that passes through the vehicle body 82, the shield of the drive system power line 40c, and the housing 49. The second path is a path that passes through the vehicle body 82, the earthing wire 90, the housing 25, the housing 28, the shield of the drive system power line 40a, and the housing 49. The third path is a path that passes through the vehicle body 82, the earthing wire 92, the housing 35, the housing 38, the shield of the drive system power line 40b, and the housing 49. That is, the negative line of auxiliary power line 50 is configured to include the first to third paths. At this time, the resistance value of the shields of drive power lines 40a to 40c is higher than that of earth part 84, and therefore the resistance value of the negative line is high and the voltage drop due to the negative line is large, so that load voltage Vlo is low and voltage difference ΔV is large. The process of step S150 is performed taking this into consideration.

[0030] In the embodiment, by operating a specific accessory among the multiple accessories 54 that is located away from the DC / DC converter 48 (at a position where the current path is longer), the difference in voltage drop on the negative side line depending on whether the earth part 84 is attached or not can be made more noticeable, and the difference in voltage difference ΔV depending on whether the earth part 84 is attached or not can be made more noticeable. Also, by increasing the output voltage Vo of the DC / DC converter 48 (for example, to the allowable output voltage or a value slightly lower than that), the current flowing through the auxiliary power line 50 and the specific load can be increased, and the difference in voltage drop on the negative side line depending on whether the earth part 84 is attached or not can be made more noticeable, and the difference in voltage difference ΔV depending on whether the earth part 84 is attached or not can be made more noticeable.

[0031] When the voltage difference ΔV is equal to or smaller than the threshold value ΔVref in step S150, it is determined that the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82 (step S160), the electric vehicle 10 is set to the ready-on state (step S170), and this routine ends. With the ready-on state, the electric vehicle 10 is ready to run.

[0032] When the voltage difference ΔV is greater than the threshold value ΔVref in step S150, it is determined that the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82 (step S180), the warning light 74 is turned on (step S190), and this routine is terminated without turning on the ready-on state. In the case where the negative side line of the auxiliary power line 50 is configured including the above-mentioned first to third paths, if the current continues to flow, there is a concern that the shields of the drive power lines 40a to 40c may overheat. In the embodiment, when it is determined that the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82, the ready-on state is not turned on, thereby preventing overheating of the shields of the drive power lines 40a to 40c. That is, the shields and the like can be protected. In addition, by turning on the warning light 74, it is possible to notify the user that the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82.

[0033] In the power system mounted on the electric vehicle 10 of the embodiment described above, when the voltage difference ΔV between the output voltage Vo of the DC / DC converter 48 and the load voltage Vlo of a specific auxiliary device is equal to or smaller than the threshold value ΔVref, it is determined that the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82, and when the voltage difference ΔV is larger than the threshold value ΔVref, it is determined that the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82. In this manner, it is possible to determine whether the earth part 84 is attached to the reinforcing member 80 and the vehicle body 82.

[0034] In the power system of the embodiment, when it is determined based on the voltage difference ΔV that the ground part 84 is not attached to the reinforcing member 80 and the vehicle body 82, the warning light 74 is turned on to notify the user. However, the user may be notified by displaying a message on a display (not shown) or by outputting a sound from a speaker (not shown). Also, such a notification may not be given.

[0035] In the power system of the embodiment, when it is determined based on the voltage difference ΔV that the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82, the system is not set to be ready-on. However, the system may be set to be ready-on for evacuation running. Examples of evacuation running include limiting the driving of the front motor 24 and the rear motor 34, limiting the driving of the DC / DC converter 48, and limiting the operation of at least some of the multiple accessories 54. Even when the earth part 84 is not attached to the reinforcing member 80 and the vehicle body 82, the shields of the drive system power lines 40a, 40b, and 40c do not immediately overheat, so in this modified example, evacuation running is permitted.

[0036] In the embodiment, the power system is mounted on an electric vehicle 10 that includes a front motor 24 and a rear motor 34. However, the power system may be mounted on an electric vehicle that includes either the front motor 24 or the rear motor 34. Also, the power system may be mounted on a hybrid vehicle that includes an engine in addition to at least one of the front motor 24 and the rear motor 34.

[0037] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section on Means for Solving the Problems will be described below. In the embodiment, the DC / DC converter 48 corresponds to the "power supply device", a specific auxiliary device among the multiple auxiliary devices 54 that is separated from the DC / DC converter 48 corresponds to the "electrical load", and the main ECU 70 corresponds to the "control device".

[0038] The correspondence between the main elements of the Examples and the main elements of the invention described in the Summary of the Problem column does not limit the elements of the invention described in the Summary of the Problem column, since the Examples are examples for specifically explaining the mode for implementing the invention described in the Summary of the Problem column. In other words, the interpretation of the invention described in the Summary of the Problem column should be based on the description in that column, and the Examples are merely a specific example of the invention described in the Summary of the Problem column.

[0039] Although the form for carrying out the present invention has been described above using examples, the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms without departing from the scope of the gist of the present invention. [Industrial Applicability]

[0040] The present invention can be used in the power system manufacturing industry and the like. [Explanation of symbols]

[0041] 10 electric vehicle, 20 front wheels, 21 front axle, 22 front differential gear, 23 front drive shaft, 24 front motor, 25, 28, 38, 45, 57, 71 housing, 26 front inverter, 27 front ECU, 30 rear wheels, 31 rear axle, 32 rear differential gear, 33 rear drive shaft, 34 rear motor, 35 housing, 36 rear inverter, 37 rear ECU, 40, 40a, 40b, 40c drive power line, 41c corrugated tube, 41n negative power line, 41p positive power line, 41s shield, 42 main battery, 44 battery ECU, 46 system main relay, 48 DC / DC converter, 49 housing, 49i voltage sensor, 49o voltage sensor, 50 auxiliary power line, 52 Auxiliary battery, 54 Auxiliary, 56 Auxiliary ECU, 70 Main ECU, 71 Housing, 72 Power switch, 74 Warning light, 80 Reinforcing member, 82 Vehicle body, 84 Earth parts, 90, 92 Earthing wire.

Claims

1. A power supply device for supplying DC power to a power line; an electrical load connected to the power line; A control device that controls the power supply device; A power system equipped with the above and mounted on a vehicle, The power line includes a positive line and a negative line, the negative electrode side line includes a negative electrode connection part connected to the power supply device, a vehicle body to which the electric load is connected, and a connection part for connecting the negative electrode connection part and the vehicle body, When a voltage difference between an output voltage of the power supply device between the vehicle body and a voltage of the electric load between the vehicle body and the power supply device is equal to or smaller than a threshold value, the control device determines that the negative electrode connection part and the vehicle body are connected by the connection part, and when the voltage difference is larger than the threshold value, determines that the negative electrode connection part and the vehicle body are not connected by the connection part. Power system.

2. 2. The power system of claim 1, the power supply device is a DC / DC converter that reduces the voltage of power of a second power line to which a drive device for traveling and a power storage device are connected and supplies the power to the power line; a housing of the power storage device is fixed to the vehicle body, The second power line includes a second positive line and a second negative line, and a shield covering the second positive line and the second negative line. Power system.

3. 3. The power system according to claim 1, the control device operates the electric load to obtain a voltage of the electric load while controlling the electric power supply device so that the voltage of the power line becomes a target voltage; Power system.

4. A power system according to any one of claims 1 to 3, When the control device determines that the negative electrode connection part and the vehicle body are not connected by the connection part, the control device limits the operation of the power supply device compared to when the control device determines that the negative electrode connection part and the vehicle body are connected by the connection part. Power system.

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