JP4933681B1 - Vehicle battery charging system - Google Patents

Abstract

In a method of obtaining power with a semiconductor thermoelectric conversion element using waste heat of an engine that uses fossil fuel, a space is created between the heat source and the thermoelectric conversion element in order to protect the thermoelectric conversion element and suppress power fluctuation, A method of adjusting the flow rate of the heat medium by flowing the heat medium, a method of controlling the temperature of the heat source to optimize the engine cooling and the power generation of the thermoelectric conversion element, and a method of controlling the connection between the thermoelectric conversion element and the battery according to the temperature However, there is a possibility that the control means may be expensive, and the method using a piezoelectric element or the method using a fan cannot generate power when the car stops and the power generation capacity is small and charging is performed. Is difficult. Solar power generation has a problem of poor efficiency because it cannot generate power on rainy days and nights.
In a vehicle battery charging system according to the present invention, cooling water (antifreeze) is forcibly applied to a heat sink 71 fixed to a thermoelectric conversion element unit in which modules of a plurality of semiconductor thermoelectric conversion elements are connected in parallel and in series. A rotor (including a chopper and a switch mechanism for electrically disconnecting the thermoelectric conversion element unit 70 and the charge controller 4 from each other), a thermoelectric converter 2 to which a cooling pipe 74 is circulated by a pump 72 driven by the engine 1. 6), a mechanical chopper 3 having a pulley A10 that transmits rotation of the cooling fan 13 and the engine 1 outside the case of the insulating material, and a charge controller that controls voltage boosting and charging voltage and current. 4 and a battery 5 attached to the vehicle, and the thermoelectric converter 2 is disposed around the engine 1. Air is blown onto a part of the cooling pipe 74 by the cooling fan 13 to cool it, and a temperature difference from the heat source side (engine 1) is generated. The cooling fan 13 is rotated by the engine 1 via a belt (not shown).
The charge controller 4 once boosts and smoothes the output voltage of the thermoelectric conversion element unit 70, and then the voltage and current are controlled by a DC-DC converter to supply charging power to the battery 5. Charging is continued when the engine 1 is rotating and the temperature is high while the vehicle is stopped. When the engine 1 is stopped, the charging is stopped by being electrically disconnected from the thermoelectric conversion element unit 70. To do.
[Selection] Figure 1

Description

The present invention relates to a vehicle battery charging system using a semiconductor thermoelectric conversion element using waste heat of an engine that uses fossil fuel in a vehicle.

As a means for recovering waste heat of an engine using fossil fuel, methods for obtaining electric power with a semiconductor thermoelectric conversion element (see, for example, Patent Document 1, Patent Document 4, and Patent Document 6) have been proposed. In addition, a method of generating electricity in a piezoelectric element by utilizing vibration of a vehicle body and charging a battery (see, for example, Patent Document 2), or a method of rotating a fan with flowing air during traveling to obtain electric power by turning a generator ( For example, see Patent Document 3). Furthermore, a method of charging the battery with electric power generated by solar power generation (see, for example, Patent Document 5) has been proposed.

JP-A-10-309088 JP 2011-093505 A JP 2010-112367 A JP 2009-133210 A JP 2006-340544 A JP 2001-023666

In the method of obtaining electric power with a semiconductor thermoelectric conversion element using waste heat of an engine using fossil fuel proposed in the above, between the heat source and the thermoelectric conversion element in order to protect the thermoelectric conversion element and suppress output power fluctuation. Create a space and flow the heat medium to adjust the flow rate (Patent Document 1), or control the temperature of the heat source (Patent Document 6) to optimize engine cooling and power generation of the thermoelectric conversion element (Patent Document 4) Has been. Moreover, although it is supposed that the connection of a thermoelectric conversion element and a battery is controlled by temperature (patent document 4), there exists a possibility that a control means may become expensive in any method, and the method using a piezoelectric element (patent document 2). In a method using a fan or a fan (Patent Document 3), it is difficult to generate power when the vehicle is stopped, and power generation capacity is small and charging is difficult. In solar power generation (Patent Document 5), there is a problem that power generation is not possible on rainy days and nights, so efficiency is poor.

In order to solve such a problem, the vehicle battery charging system according to the present invention includes a plurality of semiconductor thermoelectric conversion element modules fixed to one thermoelectric conversion element unit connected in parallel and in series, It consists of a thermoelectric converter with a fixed cooling pipe that circulates cooling water (antifreeze) with a pump driven by the engine, a switch mechanism that electrically disconnects the thermoelectric conversion element unit and the charge controller, and a chopper. A mechanical chopper having a cooling fan and a pulley for transmitting the engine rotation to the outside of the case, a charge controller for controlling voltage boosting and charging voltage and current, and a vehicle. It consists of an attached battery.

The module of the semiconductor thermoelectric conversion element is a thermoelectric generation module based on the Seebeck effect in which a plurality of chips of P-type semiconductor and N-type semiconductor are combined, and one thermoelectric conversion element unit in combination of a plurality of thermoelectric generation modules is provided around the engine. It is arranged. Since the Seebeck effect increases in efficiency as the temperature difference increases, cooling water (antifreeze) is forcibly circulated through a heat sink for cooling and a cooling pipe fixed to the heat sink, and air is supplied to a part of the cooling pipe with a cooling fan. It is sprayed and cooled to create a temperature difference from the heat source side (engine). The cooling water is equivalent to the antifreeze used in the engine, and the pump and fan for circulating the cooling water are rotated by the engine via a belt.

The mechanical chopper performs the function of the chopper of the switching power supply mechanically. In order to widen the operating range of the charge controller by boosting when the engine temperature is low and the output voltage of the thermoelectric conversion element unit is low when starting the vehicle. Is acting on. In order to prevent the thermoelectric conversion element unit from being damaged due to a short circuit, a plurality of sliders functioning as power switches are incorporated, and the output of the thermoelectric conversion element unit is opened when the engine is stopped. The built-in rotor is rotated by the engine via a belt on a pulley attached outside the case.

The charge controller once boosts and smoothes the output voltage of the thermoelectric conversion element unit, and then the voltage is boosted again by the DC-DC converter, and the voltage and current are controlled to supply charging power to the battery. While the vehicle is stopped, the charging is continued when the engine is rotating and the temperature is high. When the engine is stopped, the charging is stopped by being electrically disconnected from the thermoelectric conversion element unit.

ADVANTAGE OF THE INVENTION According to this invention, the alternator of a general vehicle and a hybrid vehicle can be abbreviate | omitted, the burden concerning an engine can be made small, and the vehicle battery charging system which can aim at the improvement of a fuel consumption can be provided.

1 is an external view of a vehicle battery charging system according to an embodiment of the present invention. It is an expanded external view of the mechanical chopper. It is an expanded sectional view at the time of rotation stop of the mechanical chopper. It is an expanded sectional view at the time of rotation of the mechanical chopper. It is an expansion external view of the thermoelectric converter. It is an expanded external view of the mechanical chopper rotor. It is a block diagram of the electric circuit.

Embodiments of the present invention will be described below with reference to the drawings.
The thermoelectric converter 2 is fixed directly or with a mounting bracket (not shown) at an outer peripheral position where the engine waste heat of the engine 1 is transmitted. The fixed position is a position where the pulley B73 protrudes outside the engine 1 and can transmit rotation from the engine 1 via a belt (not shown). When the pump 72 is attached to the vehicle body in order to avoid vibrations of the engine 1, the pump 72 and the cooling pipe 74 are connected by a rubber tube (not shown).

The mechanical chopper 3 incorporates a rotor (FIG. 6) and is covered with insulating cases A11 and B12 so that both cases are closely fixed. Both cases are fixed to the vehicle body or the engine 1 at a position where the pulley A10 protrudes outside the engine 1, and the rotation is transmitted from the engine 1 via a belt (not shown). Terminals 14a, b, and c are integrally formed in case A11, and carbon brushes 30a, b, and c are always slidable by springs 50a, b, and c so that they can freely move up and down inside slider A53 (30c). And contact with the slider B54 (30a, b). Wires (not shown) for wiring are drawn out from the carbon brushes 30a, 30b, and 30c. Similarly, the terminal 14d is integrally formed in the case B12, and the carbon brush 30d is always pressed against and in contact with the slider C55 by a spring 50d so that it can freely move up and down. An electric wire (not shown) to be wired is drawn out from the carbon brush 30d.

On the shaft 34 of the rotor (FIG. 6), an insulating chopper drum 31 and a weight fixture 33, a pulley A10 outside the case A11, and a cooling fan 13 outside the case B12 are fixed. An insulating material switch drum 32 has a shaft 34 slidably fitted therein. Two weights 51a and 51b are fixed to the respective leaf springs 52a and 52b. One end of each of the leaf springs 52a and 52b is fixed to the weight fixture 33 and the other end is fixed to the switch drum 32. The shaft 34 passes through the case A11 and the case B12 in a rotatable manner.

Around the outer periphery of the insulating chopper drum 31, a slider A53 (copper thin plate) and a slider B54 (copper thin plate) partially cut into a comb shape at equal intervals are wound and fixed. Similarly, a plurality of cut out sliders C55 (copper thin plate) are also wound around the outer periphery of the switch drum 32, and the tip of the remaining portion is bent so as not to hit the chopper drum 31. The chopper drum 31 is brought into contact with the chopper drum 31 when moved.

Next, the operation will be described.
When the engine 1 is stopped, the slider A53 of the chopper drum 31 and the slider C55 of the switch drum 32, which function as a power switch for the rotor built in the mechanical chopper 3, are not in contact with each other. The output is open. When the engine 1 starts to rotate, the chopper drum 31, the switch drum 32, and the weight fixture 33 start to rotate at the same time, and the weights 51a, 51b fixed to the leaf springs 52a, 52b are pushed outward by centrifugal force, and the switch drum 32 is rotated. Is pulled along the shaft 34. At this time, a part of the plurality of sliders C55 of the switch drum 32 rises and contacts the slider A53 of the chopper drum 31 and is electrically connected.

The carbon brush 30a that contacts the portion of the slider B54 that is cut into a comb shape by rotating the chopper drum 31 repeats conduction and non-conduction at equal intervals, and is arranged in the inside of the charging controller 4. A current is passed through (T) to boost the output voltage of the secondary coil (T). The boosted voltage is smoothed and supplied to a DC-DC converter built in the charge controller 4 to be controlled to a voltage and current suitable for charging the battery 5.

By boosting the output voltage of the thermoelectric conversion element unit 70, it is possible to reduce the number of modules of the semiconductor thermoelectric conversion elements, thereby miniaturizing the thermoelectric converter 2 and at the same time reducing the cost. Existing vehicles can also be used as an alternative to alternators.

DESCRIPTION OF SYMBOLS 1 Engine 33 Weight fixture 2 Thermoelectric converter 34 Shaft 3 Mechanical chopper 50 Spring 4 Charge controller 51 Weight 5 Battery 52 Leaf spring 10 Pulley A 53 Slider A
11 Case A 54 Slider B
12 Case B 55 Slider C
13 Cooling fan 70 Thermoelectric conversion element unit 14 Terminal 71 Heat sink 30 Carbon brush 72 Pump 31 Chopper drum 73 Pulley B
32 Switch drum 74 Cooling pipe

Claims (3)

Cooling in which cooling water (antifreeze) is forcibly circulated by a pump driven by the engine through a single heat sink fixed to a single thermoelectric conversion element unit in which a plurality of semiconductor thermoelectric conversion element modules are connected in parallel and in series A rotor composed of a thermoelectric converter with a fixed pipe, a switch mechanism that electrically separates the thermoelectric conversion element unit and the charge controller, and a chopper is built in to transmit the cooling fan and engine rotation to the outside of the case. A vehicle battery charging system comprising a mechanical chopper having a pulley, a charge controller for controlling voltage boosting and charging voltage and current, and a battery attached to the vehicle. Air is blown to a part of the cooling pipe with a cooling fan to cool it and cause a temperature difference with the heat source side (engine). Cooling water is equivalent to the antifreeze liquid used in the engine. The vehicle battery charging system according to claim 1, wherein the vehicle battery charging system is rotated by an engine. In order to increase the output voltage of the thermoelectric conversion element unit by the action of the rotor chopper built in the mechanical chopper to widen the operating range of the charge controller and to prevent the thermoelectric conversion element unit from being damaged by a short circuit. The vehicle battery charging system according to claim 1 or 2, wherein a plurality of sliders functioning as power switches are incorporated.

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