JPH11107749A - Cooling system of hybrid electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure proper operation and movement of a generator, an inverter, an electric motor for traveling, etc. SOLUTION: This hybrid electric vehicle is provided with a cooling circuit 30 for an engine for cooling an engine, a cooling circuit 22 for motor devices for cooling at least a generator, an inverter, and a electric motor for traveling, and also a bypass passage 26 for bypassing the radiator 20 of the cooling circuit 22 for motor devices. A heat exchanger 31 for applying heat exchange to cooling water for the cooling circuit 30 for engine is provided in the course of the bypass 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling system including a cooling circuit for a motor device such as a generator, an inverter, and a traveling electric motor of a hybrid electric vehicle, and a cooling circuit for an engine.

[0002]

2. Description of the Related Art Conventionally, there is a hybrid electric vehicle in which an engine and an electric motor are combined to improve exhaust emission.

[0003] Such a hybrid electric vehicle includes a generator driven by an engine, and a battery for storing the generated electric power, and the electric vehicle for driving is driven by using these as a power source via an inverter and travels. .

[0004]

In such a hybrid electric vehicle, in addition to an engine cooling circuit for cooling the engine, these hybrid electric vehicles are required to maintain the temperatures of a generator, an inverter, an electric motor for traveling and the like appropriately. It is necessary to provide a cooling circuit for a motor device for cooling a generator, an inverter, an electric motor for traveling, and the like.

However, when a cooling circuit for a motor device is provided as described above, the temperature of a generator, an inverter, an electric motor for traveling, and the like can be prevented from becoming higher than a set temperature, but the cooling water temperature of the cooling circuit is reduced. If it is low, the operability and efficiency of these generators, inverters, electric motors for traveling, and the like will deteriorate. In particular, the inverter of a semiconductor device becomes difficult to operate at a low temperature (near the minimum operating temperature of a semiconductor).

Japanese Patent Application Laid-Open No. Hei 6-54409 discloses heating engine oil or engine cooling water with motor cooling oil, and Japanese Patent Application Laid-Open No. Hei 6-319205 discloses heating engine cooling water with extra regenerative power. Japanese Patent Application Laid-Open No. 8-168103 discloses a device that radiates heat from regenerative electric power from a radiator, in which the amount of power generation is controlled according to the temperature of engine cooling water.

An object of the present invention is to provide a cooling system for a hybrid electric vehicle which can solve such problems.

[0008]

According to a first aspect of the present invention, there is provided a hybrid electric vehicle including a generator driven by an engine, a battery, and a traveling electric motor driven by an inverter using the generator as a power source. An engine cooling circuit for cooling the engine, at least a generator,
An inverter and a motor device cooling circuit for cooling the traveling electric motor; and a bypass passage for bypassing a radiator of the motor device cooling circuit, and a heat exchange between the cooling water for the engine cooling circuit and heat in the bypass passage. A heat exchanger is provided.

According to a second aspect, in the first aspect, a water temperature sensor for detecting a cooling water temperature of a cooling circuit for a motor device,
Valve means for switching between a radiator passage and a bypass passage;
A control device for controlling the valve means in accordance with the detection value of the water temperature sensor.

In a third aspect based on the second aspect, the control device opens the bypass passage when the detected value of the water temperature sensor is less than a set value.

[0011]

According to the first, second and third aspects of the invention, the generator, the inverter, the electric motor for traveling and the like can be operated and operated at an appropriate temperature, and these high functions can be secured. Reliability is improved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a power room 1 provided at the rear of a vehicle such as a bus. Reference numeral 2 denotes an engine, 3 denotes a generator driven by the engine 2, and 4 denotes a battery for storing electric power generated by the generator 3. , 5 and 6 are running motors driven by a generator 3 and a battery 4 via an inverter 7.

Partition walls are formed at the front (upper side), upper part, etc. of the power room 1, the left and right sides are provided on the outer wall panel 8 of the vehicle, and the rear side (rear side of the vehicle) is provided with a door for inspection and the like. Surrounded by the rear panel of the vehicle.

The engine 2 is arranged horizontally on the left side of the power room 1 (left side of the vehicle) in the figure, and the generator 3 is directly connected to the engine 2. 9 is an air cleaner. The electric motors 5 and 6 are mounted on the speed reducer 10 on the right side of the power room 1 (right side of the vehicle), and the driving force is transmitted from the drive shaft and the differential device to the drive wheels via the speed reducer 10.

Four inverters 7 are provided (one for the generator 3, two for the traveling motors 5 and 6, one for the auxiliary drive motor), and the right side of the power room 1 (the right side of the vehicle). The battery 4 is arranged in the battery room 12 above the inverter room 11.

Generator 3, motors 5, 6 and inverter room 1
Auxiliary equipment such as an air compressor 13, an air conditioner unit 14, and a radiator 20 are arranged between the control unit 1 and the control unit 1. The radiator 20 is assembled with the electric fan 21 as shown in FIGS. 2 and 3, is unitized, and is disposed near the air conditioner unit 14 (on the rear side of the vehicle).

A heat shield plate 15 is provided between the engine 2 and the generator 3 so that hot air around the engine 2 does not flow into the vicinity of the generator 3. The heat shield plate 15 includes an engine room 16 and a generator room 17 from the front to the rear of the power room 1.
And the engine room 16 is extended to the upper part of the power room 1 so as to also define the inverter room 11 and the battery room 12.

A motor device cooling circuit 22 for cooling the generator 3, the motors 5, 6, the inverter 7, and the like is provided.

In this motor device cooling circuit 22, a cooling jacket (not shown) formed on each of the generator 3, the electric motors 5, 6, the inverter 7, and the like, and the radiator 20 connect a pipe 23 as shown in FIG. Connected via a pipe 23
The electric pump 24 is installed in the middle. However, FIG.
Here, the generator 3, the electric motors 5, 6, the inverter 7, and the like are represented as motor equipment 25.

A bypass passage 26 for bypassing the radiator 20 is formed, and a radiator passage 27 and a bypass passage 2 are provided at an inlet and an outlet of the bypass passage 26.
6 and directional switching valves 28 and 29 for switching between the engine cooling circuit 30 and the engine cooling circuit 30
A heat exchanger 31 is provided for exchanging heat with cooling water from the heat exchanger.

The engine cooling circuit 30 is formed of an engine radiator, a water pump, and a piping system (not shown), and the cooling water that bypasses the engine radiator or that is downstream of the engine radiator is supplied to the heat exchanger 3.
Sent to 1.

A water temperature sensor 3 for detecting the temperature of the cooling water is provided upstream of the direction switching valve 28 of the cooling circuit 22 for the motor device.
2 is installed.

Based on the value detected by the water temperature sensor 32,
The control device 33 controls the electric fan 21 that sends cooling air to the radiator 20 and the direction switching valves 28 and 29.

In this case, when the detected value of the water temperature sensor 32 is equal to or higher than a set value (for example, 0 ° C.), the direction switching valve 2 is closed so that the bypass passage 26 is closed and the radiator passage 27 is opened.
When the detected value of the water temperature sensor 32 reaches a predetermined high temperature, the electric fan 21 is driven. on the other hand,
When the detection value of the water temperature sensor 32 is less than a set value (for example, 0 ° C.), the radiator passage 27 is closed and the bypass passage 26 is closed.
Are controlled to open the motor (the electric fan 21 is turned off).

With this configuration, when the cooling water temperature of the motor device cooling circuit 22 is lower than the set value, the cooling water of the motor device cooling circuit 22 does not pass through the radiator 20,
The engine cooling circuit 2 sent to the heat exchanger 31 in the bypass passage 26 and maintained at a predetermined temperature on the engine side.
Heated by the cooling water from 6.

Therefore, the temperatures of the generator 3, the motors 5, 6, the inverter 7 and the like are maintained at or above the set values, so that the generator 3, the motors 5, 6 and the like can be kept in a good operating state and operating state. In addition, a stable operation of the inverter 7 which is particularly susceptible to a low temperature can be obtained.

On the other hand, when the cooling water temperature of the motor device cooling circuit 22 exceeds the set value, the cooling water of the motor device cooling circuit 22 passes through the radiator 20 and is supplied to the generator 3, the motors 5, 6 and the inverter. 7 and the like, and when the cooling water temperature reaches a predetermined high temperature, the electric fan 21 is driven.

Therefore, the temperatures of the generator 3, the electric motors 5, 6, the inverter 7 and the like do not rise above a predetermined value.
The generator 3, the electric motors 5, 6 and the inverter 7 are operated and operated at an appropriate temperature.

Therefore, high functions and reliability of the generator 3, the electric motors 5, 6 and the inverter 7 are ensured.

[Brief description of the drawings]

FIG. 1 is an arrangement configuration diagram showing an embodiment.

FIG. 2 is a layout view of a radiator as viewed from the rear of the vehicle.

FIG. 3 is a layout view of a radiator viewed from a side of the vehicle.

FIG. 4 is a configuration diagram of a cooling circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power room 2 Engine 3 Generator 4 Battery 5, 6 Electric motor 7 Inverter 11 Inverter room 12 Battery room 13 Air compressor 14 Air conditioner unit 20 Radiator 21 Electric fan 22 Motor device cooling circuit 23 Piping 24 Electric pump 25 Motor device 26 Bypass passage 27 Radiator passage 28,29 Direction switching valve 30 Engine cooling circuit 31 Heat exchanger 32 Water temperature sensor 33 Control device

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Ienaka Nissan Diesel Industry Co., Ltd. Inside the corporation

Claims (3)

[Claims] 1. A hybrid electric vehicle including a generator driven by an engine, a battery, and a traveling electric motor driven by an inverter using the generator as a power source, an engine cooling circuit for cooling the engine, At least a generator, an inverter, and a motor device cooling circuit for cooling the traveling electric motor are provided, while a bypass passage is provided to bypass a radiator of the motor device cooling circuit, and the engine cooling circuit is cooled in the middle of the bypass passage. A cooling system for a hybrid electric vehicle, comprising a heat exchanger for exchanging heat with water. 2. A water temperature sensor for detecting a cooling water temperature of a cooling circuit for a motor device, valve means for switching between a radiator passage and a bypass passage, and a control device for controlling the valve means in accordance with a detection value of the water temperature sensor. The cooling system for a hybrid electric vehicle according to claim 1. 3. The cooling system for a hybrid electric vehicle according to claim 2, wherein the control device opens the bypass passage when a detected value of the water temperature sensor is less than a set value.