Electric machinery

Abstract

The system ensures proper ventilation inside the enclosure of power equipment mounted in vehicles, effectively suppressing migration caused by condensation. [Solution] The power equipment of this disclosure includes a housing and electrical components that generate heat when energized and are housed within the housing, and is a power equipment mounted on a vehicle, and includes a humidity sensor for detecting humidity inside the housing, an intake fan for drawing outside air into the housing, an exhaust fan for expelling air from inside the housing to the outside, and a control device that activates the intake fan and the exhaust fan when the approach of a driver to the vehicle is detected and the humidity inside the housing detected by the humidity sensor is above a predetermined value.

Description

Technical Field

[0001] The present disclosure relates to an electric device mounted on a vehicle.

Background Art

[0002] Conventionally, a vehicle including an accessory housing formed below a floor panel and electric devices such as an inverter for vehicle drive housed in the accessory housing is known (see, for example, Patent Document 1). In this vehicle, a ventilation hose extends from the housing of the electric device toward the upper floor panel that serves as the ceiling surface of the accessory housing, and the opening at the end of the ventilation hose communicates with the passenger compartment. Thereby, it is possible to suppress condensation inside the housing of the electric device and to suppress the intrusion of water into the housing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, it is difficult to ventilate the inside of the housing well by simply connecting a ventilation hose to the housing of the electric device. Therefore, in the above conventional vehicle, the electric device may be energized in a state where the inside of the housing is highly humid, and there is a risk of causing short-circuit failures and the like due to migration caused by condensation. In addition, in order to discharge the water vapor inside the housing to the outside, it is also conceivable to install a porous film made of polytetrafluoroethylene (PTFE) that allows water vapor to pass through at the opening formed in the housing of the electric device. However, even if such a porous film is installed at the opening of the housing, an air flow is not sufficiently formed inside the housing, and it is difficult to discharge the water vapor existing at a location separated from the opening to the outside of the housing.

[0005] Therefore, the primary purpose of this disclosure is to properly ventilate the inside of the enclosure of power equipment mounted on a vehicle to effectively suppress migration caused by condensation. [Means for solving the problem]

[0006] The power equipment of this disclosure is mounted on a vehicle and includes a housing, electrical components that generate heat when energized and are housed within the housing, a humidity sensor for detecting humidity inside the housing, an intake fan for drawing outside air into the housing, an exhaust fan for expelling air from the housing to the outside, and a control device. The control device activates the intake fan and exhaust fan when it detects the approach of a driver to the vehicle and the humidity inside the housing detected by the humidity sensor is above a predetermined value. This replaces the air inside the housing before the vehicle starts moving, preventing the power equipment from being energized when the housing is in a highly humid state as the vehicle starts moving. As a result, the power equipment of this disclosure can properly ventilate the inside of the housing and effectively suppress migration due to condensation. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic diagram showing a vehicle including the power equipment of this disclosure. [Figure 2] This is a schematic diagram of the power equipment shown in this disclosure. [Figure 3] This flowchart shows the routines executed by the control device of the power equipment of this disclosure. [Modes for carrying out the invention]

[0008] Next, with reference to the drawings, embodiments for carrying out the invention of this disclosure will be described.

[0009] Figure 1 is a schematic diagram showing an electric vehicle 1 including the power equipment of the present disclosure. The electric vehicle 1 shown in the figure is a battery electric vehicle (BEV) including a battery 2, a normally open system main relay SMR, an inverter 3 as the power equipment of the present disclosure, a motor generator MG, and an electronic control unit (hereinafter referred to as "ECU") 10. However, the electric vehicle 1 may also be a hybrid vehicle (HEV, PHEV) including an internal combustion engine in addition to the battery 2 and motor generator MG, etc.

[0010] Battery 2 is, for example, a lithium-ion secondary battery or nickel-metal hydride secondary battery having a rated output voltage of 200 to 800V. The positive terminal of battery 2 is connected to the positive power line PL via the positive relay of the system main relay SMR. The negative terminal of battery 2 is connected to the negative power line NL via the negative relay of the system main relay SMR. Inverter 3 is connected to battery 2 via the positive power line PL, the negative power line NL, and the system main relay SMR. Inverter 3 converts DC power from battery 2 into three-phase AC power and supplies it to the motor generator MG, and also converts three-phase AC power (regenerative power) from the motor generator MG into DC power and supplies it to battery 2.

[0011] The motor-generator MG is a synchronous generator-motor (three-phase AC motor). The rotor of the motor-generator MG is connected to the drive shaft DS, which rotates integrally with the drive wheel DW, via a power transmission system including a reduction gear and differential gear. The motor-generator MG is driven by power from the inverter 3 (battery 2) and outputs drive torque (driving force) to the drive shaft DS. In addition, the motor-generator MG outputs regenerative braking torque to the drive shaft DS when braking the electric vehicle 1.

[0012] Figure 2 is a schematic diagram showing the inverter 3. As shown in the figure, the inverter 3 includes a housing 30 and a circuit board SB located inside the housing 30. The circuit board SB is equipped with multiple transistors T (switching elements), such as IGBTs (power semiconductors), and multiple diodes D, such as six diodes D, connected in parallel in opposite directions to each transistor T, as well as multiple capacitors C. These electrical components, such as transistors T, diodes D, and capacitors C, generate heat when energized.

[0013] Furthermore, a first cylindrical portion 31 and a second cylindrical portion 32 extend outward from a pair of opposing side walls of the inverter 3's housing 30. The first cylindrical portion 31 and the second cylindrical portion 32 are provided on the housing 30 so as to face each other directly or diagonally, and can communicate the inside and outside of the housing 30, respectively. An intake fan 33, which is an electric fan driven by power from an auxiliary battery (not shown), is arranged inside the first cylindrical portion 31. An exhaust fan 34, which is an electric fan driven by power from the same auxiliary battery, is arranged inside the second cylindrical portion 32. The intake fan 33 can take in outside air into the housing 30 through the opening of the first cylindrical portion 31 (left end in Figure 2). The exhaust fan 34 can discharge air from inside the housing 30 to the outside through the opening of the second cylindrical portion 32 (right end in Figure 2). Furthermore, an intake-side opening / closing cover 35 is installed at the opening of the first cylindrical section 31, and an exhaust-side opening / closing cover 36 is installed at the opening of the second cylindrical section 32.

[0014] The intake-side opening / closing cover 35 includes a support portion 35a, two cover members 35c, and, for example, an electromagnetic locking device 37 (see Figure 1). The support portion 35a is positioned to traverse the central part of the opening of the first cylindrical portion 31 in the height or width direction. The two cover members 35c are each rotatably supported by the support portion 35a and are biased by a spring (elastic body) (not shown) to close the opening of the first cylindrical portion 31. In this embodiment, each cover member 35c is, for example, a semicircular metal frame with a semicircular porous membrane made of, for example, polytetrafluoroethylene (PTFE) that is waterproof, dustproof, and highly breathable fixed to it. However, each cover member 35c may be a perforated plate having holes for adjusting the differential pressure between the inside and outside of the housing 30.

[0015] The locking device 37 locks the two cover members 35c to close the opening of the first cylindrical portion 31 when the device is not energized, and unlocks the two cover members 35c when power is supplied from an auxiliary battery (not shown). When the intake fan 33 is operated with the locking device 37 released, the two cover members 35c rotate around the support portion 35a inward toward the housing 30 against the biasing force of the spring, as shown in Figure 2, in response to the air pressure between the intake fan 33 and each cover member 35c falling below the ambient air pressure. This opens the opening of the first cylindrical portion 31.

[0016] The exhaust-side opening / closing cover 36 includes a support portion 36a, two cover members 36c, and, for example, an electromagnetic locking device 38 (see Figure 1). The support portion 36a is positioned to traverse the central part of the opening of the second cylindrical portion 32 in the height or width direction. The two cover members 36c are each rotatably supported by the support portion 36a and are biased by a spring (elastic body) (not shown) to close the opening of the second cylindrical portion 32. In this embodiment, each cover member 36c is, for example, a semicircular metal frame with a semicircular porous membrane made of, for example, polytetrafluoroethylene (PTFE) fixed to it. However, each cover member 36c may also be a perforated plate having holes for adjusting the differential pressure between the inside and outside of the housing 30.

[0017] The locking device 38 locks the two cover members 36c to close the opening of the second cylindrical portion 32 when the device is not energized, and unlocks the two cover members 36c when power is supplied from an auxiliary battery (not shown). When the exhaust fan 34 is operated with the locking device 38 released, the two cover members 36c rotate around the support portion 36a toward the outside of the housing 30 against the biasing force of the spring, as shown in Figure 2, in response to the air pressure between the exhaust fan 34 and each cover member 36c becoming higher than the ambient air pressure. This opens the opening of the second cylindrical portion 32.

[0018] The ECU 10 of the electric vehicle 1 includes a computer with a CPU, ROM, RAM, input / output interface, various drive circuits, various logic ICs, etc. When the electric vehicle 1 is running, the ECU 10 sets a torque command to the motor generator MG according to the required torque for the running of the electric vehicle 1, and switches and controls multiple transistors T of the inverter 3 based on the torque command. Furthermore, when the electric vehicle 1 is braking, the ECU 10 switches and controls multiple transistors T of the inverter 3 so that the motor generator MG outputs its share of the regenerative braking torque to a pair of drive wheels DW.

[0019] Further, the ECU 10 supplies power from an auxiliary battery (not shown) to the intake fan 33, exhaust fan 34, and locking devices 37, 38 of the inverter 3, and controls these auxiliary devices. Further, the ECU 10 acquires the humidity H detected by a humidity sensor 39 disposed inside the housing 30 of the inverter 3 (e.g., on a circuit board SB). In addition, a shift position sensor 40 that detects the operation position of a shift lever (not shown), an outside vehicle key detection sensor 41, and an inside vehicle key detection sensor 42 are connected to the ECU 10. The outside vehicle key detection sensor 41 outputs an on signal when the smart key 50 of the electric vehicle 1 is outside the vehicle and within a predetermined range (e.g., a range of several meters) around the electric vehicle 1. The inside vehicle key detection sensor 42 outputs an on signal when the smart key (remote control key) 50 of the electric vehicle 1 is inside the vehicle.

[0020] Subsequently, a procedure for ventilating the inside of the housing 30 of the inverter 3 will be described while referring to FIG. 3.

[0021] FIG. 3 is a flowchart showing a routine executed by the ECU 10 when a driver of the electric vehicle 1 having the smart key 50 approaches within a predetermined range around the electric vehicle 1. When the driver having the smart key 50 approaches within a predetermined range around the electric vehicle 1, an on signal is output from the outside vehicle key detection sensor 41, and the ECU 10 is activated by a power supply ECU (not shown) that has received the on signal. Then, immediately after being activated in response to the approach of the driver to the electric vehicle 1, the ECU 10 starts executing the routine of FIG. 3.

[0022] At the start of the routine in FIG. 3, the ECU 10 acquires the humidity H inside the housing 30 detected by the humidity sensor 39 of the inverter 3 (step S100), and determines whether or not the acquired humidity H is equal to or higher than the ventilation execution humidity Href that has been adapted through prior experiments and analysis (step S110). If the humidity H is less than the ventilation execution humidity Href (step S110: NO), the ECU 10 considers that the humidity H inside the housing 30 is low and there is no risk of migration due to condensation, permits the operation of the inverter 3 (step S200), and ends the routine in FIG. 3.

[0023] Also, if the humidity H is equal to or higher than the ventilation execution humidity Href (step S110: YES), the ECU 10 starts energizing the locking devices 37 of the intake side opening / closing cover 35 and the locking devices 38 of the exhaust side opening / closing cover 36, and releases the locking of the two cover members 35c of the intake side opening / closing cover 35 and the two cover members 36c of the exhaust side opening / closing cover 36 (step S120). Further, after the locking of the two cover members 35c and the two cover members 36c is released, the ECU 10 operates the intake fan 33 and the exhaust fan 34 (step S130). As a result, the air pressure between the intake fan 33 and each cover member 35c decreases, and the two cover members 35c rotate around the support portion 35a toward the inside of the housing 30 to open the opening of the first cylindrical portion 31. Also, the air pressure between the exhaust fan 34 and each cover member 36c increases, and the two cover members 36c rotate around the support portion 36a toward the outside of the housing 30 to open the opening of the second cylindrical portion 32. As a result, outside air is taken into the housing 30 by the intake fan 33, and the air inside the housing 30 is discharged to the outside by the exhaust fan 34, and the inside of the housing 30 is ventilated.

[0024] After activating the intake fan 33 and exhaust fan 34, the ECU 10 acquires the operating position of the shift lever detected by the shift position sensor 40 and determines whether the acquired operating position is the parking position (step S140). If the operating position of the shift lever is the parking position (step S140: YES), the ECU 10 determines whether the smart key 50 is inside the vehicle based on the signal from the vehicle interior key detection sensor 42 (step S150). If the smart key 50 is not inside the vehicle but outside the vehicle (step S150: YES), the ECU 10 determines whether the smart key 50 is within a predetermined range around the electric vehicle 1 based on the signal from the vehicle exterior key detection sensor 41 (step S160).

[0025] If the smart key 50 is inside the vehicle (step S150: NO) or if the smart key 50 is within a predetermined range around the electric vehicle 1 (near the electric vehicle 1) (step S160: YES), the ECU 10 determines whether a predetermined ventilation time has elapsed since the intake fan 33 and exhaust fan 34 started operating (step S170). The ventilation time used as a threshold in step S170 is the time required for the air inside the housing 30 to be completely replaced with outside air by the operation of the intake fan 33 and exhaust fan 34, and is predetermined through experimentation and analysis. If the ventilation time has not elapsed since the intake fan 33 and exhaust fan 34 started operating (step S170: NO), the ECU 10 repeats the process from step S140 onwards after a predetermined time (a very short time) has elapsed.

[0026] If the above ventilation time has elapsed since the intake fan 33 and exhaust fan 34 started operating (step S170: YES), the ECU 10 stops the operation of the intake fan 33 and exhaust fan 34 (step S180). In response to the stopping of the operation of the intake fan 33 and exhaust fan 34, the two cover members 35c of the intake-side opening / closing cover 35 rotate outward due to the biasing force of the springs to close the opening of the first cylindrical portion 31, and the two cover members 36c of the exhaust-side opening / closing cover 36 rotate inward due to the biasing force of the springs to close the opening of the second cylindrical portion 32. Furthermore, when the intake-side opening / closing cover 35 and the exhaust-side opening / closing cover 36 are fully closed, the ECU 10 releases power to the locking devices 37 and 38 so that the two cover members 35c and the two cover members 36c are locked (step S190). Then, the ECU 10 allows the inverter 3 to operate (step S200), and terminates the routine shown in Figure 3.

[0027] Furthermore, if the shift lever is not in the parking position (step S140: NO), the ECU 10 assumes that the driver may immediately start driving the electric vehicle 1 and stops the operation of the intake fan 33 and the exhaust fan 34 (step S180). In addition, when the intake side opening / closing cover 35 and the exhaust side opening / closing cover 36 are fully closed, the ECU 10 releases power to the locking devices 37 and 38 so that the two cover members 35c and the two cover members 36c are locked (step S190), and then allows the operation of the inverter 3 (step S200), thus ending the routine in Figure 3.

[0028] On the other hand, if the smart key 50 is outside the vehicle compartment and outside the predetermined range around the electric vehicle 1 (step S160: NO), the ECU 10 assumes that the driver has left the electric vehicle 1 and that the electric vehicle 1 will not start running for some time, and in order to prevent the auxiliary battery from being depleted, it stops the operation of the intake fan 33 and the exhaust fan 34 (step S210), and when the intake side opening / closing cover 35 and the exhaust side opening / closing cover 36 are fully closed, it releases power to the locking devices 37 and 38 so that the two cover members 35c and the two cover members 36c are locked (step S220). In this case, the ECU 10 terminates the routine in Figure 3 without allowing the inverter 3 to operate.

[0029] As described above, the inverter 3, which is a power device mounted on the electric vehicle 1, includes a housing 30, a transistor T, a diode D, and a capacitor C as electrical components that generate heat when energized and are housed within the housing 30, a humidity sensor 39 that detects the humidity H inside the housing 30, an intake fan 33 that takes in outside air into the housing 30, an exhaust fan 34 that expels the air inside the housing 30 to the outside, and an ECU 10 as a control device. When the ECU 10 detects the approach of a driver to the electric vehicle 1, it starts executing the routine shown in Figure 3, and when the humidity H inside the housing 30 detected by the humidity sensor 39 is equal to or greater than the ventilation execution humidity (predetermined value) Href (step S110: YES), it activates the intake fan 33 and the exhaust fan 34 (step S130). This makes it possible to replace the air inside the housing 30 before the electric vehicle 1 starts running, and to prevent the inverter 3 from being powered when the inside of the housing 30 is in a high-humidity state when the electric vehicle 1 starts running. In other words, since it generally takes about 10 seconds of preparation time from when the driver approaches the electric vehicle 1 until the electric vehicle 1 starts moving, the routine shown in Figure 3 can be executed during this preparation time to properly ventilate the inside of the inverter 3 housing 30. As a result, the electric vehicle 1 can properly ventilate the inside of the inverter 3 housing 30 and effectively suppress migration due to condensation.

[0030] Furthermore, a unit including the first cylindrical section 31, intake fan 33, and intake-side opening / closing cover 35, and a unit including the second cylindrical section 32, exhaust fan 34, and exhaust-side opening / closing cover 36 may be arranged in multiple units at intervals in the vertical and / or depth directions in Figure 2 relative to a pair of opposing side walls of the housing 30 of the inverter 3. Also, the first and second cylindrical sections 31 and 32 may be omitted, the intake-side opening / closing cover 35 and the exhaust-side opening / closing cover 36 may be installed on the side walls of the housing 30, and the intake fan 33 and exhaust fan 34 may be arranged inside or outside the housing 30. In addition, in step S170, it may be determined whether the humidity H detected by the humidity sensor 39 is below a predetermined ventilation stop threshold, and when the humidity H becomes below the ventilation stop threshold, the processing from step S180 onward may be executed. Furthermore, the predetermined range, which is the sensing range of the smart key 50 of the exterior key sensing sensor 41, may be customizable according to the distance between the parking space of the electric vehicle 1 and the storage location of the smart key 50. Moreover, the power equipment of this disclosure is not limited to the inverter 3, but may include, for example, an on-board charging device, as long as it includes an electrical component that generates heat in response to the flow of power.

[0031] Furthermore, the invention disclosed herein is not limited in any way to the embodiments described above, and it goes without saying that various modifications can be made within the scope of this disclosure. Moreover, the embodiments described above are merely one specific form of the invention described in the summary of the invention, and do not limit the elements of the invention described in the summary of the invention. [Industrial applicability]

[0032] The invention disclosed herein can be used in industries such as the manufacturing of power equipment. [Explanation of symbols]

[0033] 1 Electric vehicle, 2 Battery, 3 Inverter, 30 Housing, 31 First cylindrical part, 32 Second cylindrical part, 33 Intake fan, 34 Exhaust fan, 35 Intake side opening / closing cover, 35a, 36a Support part, 35c, 36c Cover member, 36 Exhaust side opening / closing cover, 37, 38 Locking device, 39 Humidity sensor, 10 Electronic control unit (ECU), 40 Shift position sensor, 41 Exterior key detection sensor, 42 Interior key detection sensor, 50 Smart key, C Capacitor, D Diode, MG Motor generator, T Transistor.

Claims

[Claim 1] A power device mounted on a vehicle, comprising a housing and electrical components that generate heat when power is supplied and are housed within the housing, A humidity sensor for detecting the humidity inside the housing, The enclosure includes an intake fan that draws in outside air, An exhaust fan that expels air from inside the enclosure to the outside, A control device that activates the intake fan and the exhaust fan when the approach of a driver to the vehicle is detected and the humidity inside the housing detected by the humidity sensor is above a predetermined value, Power equipment equipped with these features.

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