JP2006266160A - Fuel control system for vehicles with bi-fuel engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel control device for a vehicle equipped with a bi-fuel engine capable of running to reduce pollutants in exhaust gas in a situation where air pollution tends to become high concentration.
SOLUTION: A vehicle 100 equipped with a bi-fuel engine capable of using two or more kinds of fuel, and an air pollution status judging means for judging an air pollution situation around the own vehicle and the air pollution status judging means. And a use fuel control means for controlling the fuel supply system so as to use a fuel in a form that emits less pollutants among the two or more types of fuel when it is determined that the substance is likely to have a high concentration.
[Selection] Figure 1

Description

  The present invention relates to a fuel control device for a vehicle equipped with a bi-fuel engine that can use two or more types of fuel.

  In recent years, in automobiles and the like, gas such as petroleum gas (LPG), natural gas (LNG or CNG: Compressed Natural Gas) and hydrogen, as well as liquid fuels such as gasoline, alcohol and light oil from the viewpoint of air pollution control and resource saving. Fuel is drawing attention. However, in the case of CNG or the like, the energy density thereof is smaller than that of gasoline or the like, so that a vehicle equipped with an engine using CNG has a shorter cruising distance than a vehicle equipped with an engine using gasoline. In addition, due to delays in infrastructure development, the number of CNG and hydrogen filling stations is not sufficient, and there are concerns about long-distance movement. In view of this, a bi-fuel engine that can use two or more kinds of liquid fuels or two or more kinds of liquid fuel and gaseous fuel has been proposed.

  By the way, various proposals have been made so that a general user can use a vehicle equipped with such a bi-fuel engine without feeling discomfort with a vehicle equipped with a mono-fuel engine. For example, in Patent Document 1, in a bi-fuel engine, a user can specify, and an optimum fuel is selected based on the load and rotation state, and an automatic operation mode, a liquid fuel operation mode, and a gas operation mode are selected. A bi-fuel engine in which three operation modes are set is disclosed.

  Further, in Patent Document 2, in a bi-fuel engine, when it is determined that the shortest supply point cannot be reached with the remaining amount of fuel currently in use using a car navigation system, the fuel used is automatically switched. A bi-fuel engine to be performed is described.

  Furthermore, in Patent Document 3, when the temperature of the fuel staying in the delivery pipe of the supply system that is not used as combustion fuel for the engine in the bi-fuel engine of LPG and gasoline reaches the upper limit value, the supply is performed. A bi-fuel engine is described in which the fuel pump of the system is driven to maintain the liquid phase.

JP 2004-257304 A JP 2004-270604 A JP 2004-36458 A

  In general, in a vehicle with a bi-fuel engine, as described above, from the viewpoint of air pollution control, a fuel with a low emission amount of air pollutants is used, and driving with a low emission amount of air pollutants is possible. As long as it is required to be done.

  The techniques described in Patent Documents 1 to 3 are in line with such demands and can be evaluated. However, these are only to use the optimum fuel suitable for the operating state, and do not consider the surrounding air pollution situation. In order to solve air pollution, which is currently a problem, especially in cities, running in a manner that reduces pollutants in exhaust gas, which is one of the causes, is performed in situations where air pollution tends to be high. is required.

  Accordingly, an object of the present invention is to solve the conventional problem and to provide a fuel control device for a vehicle equipped with a bi-fuel engine that enables traveling to reduce pollutants in exhaust gas in a situation where air pollution tends to become high concentration. It is to provide.

  A fuel control device for a vehicle equipped with a bi-bifuel engine according to an embodiment of the present invention that solves the above problem is a vehicle equipped with a bi-fuel engine that can use two or more types of fuel, and determines an air pollution situation around the host vehicle. When the air pollution status determining means and the air pollution status determining means determine that the air pollutant is likely to be high in concentration, a fuel having a form that emits less pollutant is selected from the two or more fuels. Use fuel control means for controlling the fuel supply system to be used. Here, it is preferable that the air pollution status determination means determine based on at least position information of the own vehicle, surrounding traffic congestion information, outside air temperature information, and time information.

  The fuel use control means may include a fuel switching valve control device that switches between the two or more types of fuel.

  Furthermore, the used fuel control means may include a fuel mixing valve control device that adjusts a mixing ratio of the two or more kinds of fuels.

  According to the fuel control device for a vehicle equipped with a by-by-fuel engine according to an aspect of the present invention, when the air pollution situation determination unit determines that the air pollution situation around the host vehicle is likely to have a high concentration of air pollutants, The fuel supply system is controlled by the used fuel control means so as to use a fuel in a form that emits less pollutants among two or more kinds of fuels. Therefore, it is possible to travel with less pollutant emission, and air pollution is suppressed.

  Here, according to the form in which the air pollution status determination means determines based on at least the position information of the own vehicle, the surrounding traffic congestion information, the outside air temperature information, and the time information, an existing car navigation system or an outside air temperature sensor is installed in the vehicle. It can be easily determined without increasing the cost by using an on-vehicle clock.

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

  First, an overview of a first embodiment of a vehicle 100 equipped with a bi-fuel engine to which the present invention is applied will be described with reference to FIG. 110 is a bi-fuel engine, 112 is a fuel switching valve, and 120 is a fuel container. The bi-fuel engine 110 has a fuel injection valve (not shown), which is connected to a first fuel supply system and a second fuel supply system via a fuel switching valve 112. In the first embodiment, CNG is used as the first fuel A, which is a low pollutant emission fuel, and gasoline is used as the second fuel B for normal travel. Therefore, the above-described fuel container 120 includes a CNG cylinder as the first fuel container 120A for storing the first fuel A (CNG) and a second fuel container 120B for storing the second fuel B (gasoline). Consisting of a gasoline tank. In the following description, the symbol “120” is used when generically referring to fuel containers, and when it is necessary to distinguish between different fuels, the symbols “120A” and “120A” The symbols “A” and “B” will be used for “120B” and the first and second fuels contained therein, respectively.

  The fuel injection valve and the fuel switching valve described above are controlled based on output signals from the electronic control unit 130, respectively. The electronic control unit 130 is composed of a digital computer, and is connected to a ROM (Read Only Memory), a RAM (Random Access Memory), a CPU (Microprocessor), and a constant power source connected to each other via a bidirectional bus. Includes a B-RAM (backup RAM) as a nonvolatile memory in which stored data is not lost, an input port, and an output port. The input port is connected to receive signals from the car navigation system 140, the outside air temperature sensor 150, and the in-vehicle clock 160. Furthermore, a GPS antenna 142 and a VICS antenna 144 are connected to the car navigation system 140.

  In the first embodiment of the present invention configured as described above, for example, control is performed according to the control routine shown in FIG. This control routine is executed by interruption with a predetermined period. Therefore, when the control starts, first, in step S201, the vehicle position information from the car navigation system 140 by reception of the GPS antenna 142, in step S202, the traffic congestion information from the car navigation system 140 by reception of the VICS antenna 144, step In step S203, the outside air temperature information from the outside air temperature sensor 150 is read, and in step S204, the current time information from the in-vehicle clock 160 is read. Then, the process proceeds to step S205, where the criteria will be described in detail later, but it is determined whether or not the air pollutant is likely to have a high concentration.

  If the air pollutant is likely to be high in concentration, that is, if “YES”, the process proceeds to step S206, and if “NO”, the process proceeds to step S208. In step S206 and step S208, it is determined whether or not the currently used fuel is a low pollutant emission fuel (first fuel A). This determination can be made based on the memory in the previous control routine cycle which side the fuel switching valve 112 is located on. If it is determined in step S206 that the air pollutant is likely to be in a high concentration state and it is determined that the low pollutant exhaust fuel is not in use, the process proceeds to step S207 to switch the fuel. The valve 112 is switched. That is, it is switched to use gaseous fuel (CNG) as the first fuel A which is a low pollutant emission fuel. On the other hand, when it is determined in step S206 that the low pollutant emission fuel is already being used, the process proceeds to step S207, and the fuel switching valve 112 is maintained without being switched.

  On the other hand, if it is determined in step S208 that the air pollutant is not in a situation where the concentration is not likely to be high, it is determined that the low pollutant emission fuel is not in use, the process proceeds to step S209 and the fuel is switched. The valve 112 is maintained as it is without being switched. On the other hand, if it is determined in step S208 that the low pollutant emission fuel is being used, the process proceeds to step S210, where the fuel is switched to use liquid fuel (gasoline) as the second fuel B for normal travel. Thus, when the air pollutant is likely to have a high concentration, the low pollutant emission fuel is used, and the concentration of the air pollutant is suppressed.

  Here, an example of a reference used for determining whether or not the air pollutant is likely to become a high concentration in step S205 will be described. This criterion is, for example, that there is a traffic jam section within a predetermined distance (for example, a radius of 5 km) from the own vehicle, the daytime (for example, 8:00 to 18:00), and the outside air temperature is a predetermined temperature (for example, 24 ° C.) or higher. This can be determined with reference to data which is a condition where photochemical smog is likely to occur. Other determination criteria include, for example, a congested section or a congested section within a predetermined distance (for example, a radius of 5 km) from the own vehicle, from late night to early morning (for example, 3:00 to 7:00), and The outside air temperature may be a predetermined temperature (for example, 15 ° C.) or less. This is determined with reference to data, which is a condition in which air pollutants are likely to become highly concentrated with the occurrence of the atmospheric inversion layer from midnight to early morning.

  Next, a second embodiment of the present invention will be described. In the first embodiment described above, the fuel switching valve control for switching the fuel in order to switch between the first fuel A, which is a low pollutant emission fuel, and the second fuel B for normal running, depending on the situation. In this second embodiment, the first fuel A that is a low pollutant discharge fuel and the second fuel B that is mixed with the first fuel A are included. In order to change the mixing ratio according to the above, a fuel mixing valve 114 as a fuel mixing valve control device for adjusting the mixing ratio of the fuel is included. In the second embodiment in which the first fuel A and the second fuel B are mixed and used, for example, gasoline is stored in the first fuel container 120A, and ethanol is stored in the second fuel container 120B. . The fuel mixing valve 114 and the fuel injection valve (not shown) of the bi-fuel engine 110 and the connection relationship between the first fuel supply system and the second fuel supply system are the same as the fuel switching valve of the first embodiment described above. This is the same as 112. Accordingly, the fuel mixing valve 114 is indicated by reference numeral “114” in FIG. 1 in parentheses after the reference numeral “112”.

  In the second embodiment, the control is performed according to the control routine of the flowchart shown in FIG. Steps S301 to S305 in this control routine are the same as steps S201 to S205 in the previous embodiment, and thus a duplicate description is avoided. Accordingly, in step S305, it is determined whether or not the air pollutant is likely to have a high concentration. If “YES”, the process proceeds to step S306, and if “NO”, the process proceeds to step S307. In step S307 at the time of “NO”, the fuel mixture ratio for normal traveling is maintained. That is, based on a command from the electronic control unit 130, the fuel mixture ratio of gasoline and ethanol (for example, containing 10% ethanol) by the fuel mixing valve 114 is maintained for normal travel. On the other hand, in step S305, the air pollutant is likely to have a high concentration. In other words, in step S306 when it is determined “YES”, the fuel is used so that the fuel in a form with less pollutant emission is used. The mixing ratio of the fuel is adjusted by the mixing valve 114. As this adjustment, mixing of ethanol may be stopped completely, or the ethanol content% may be further reduced.

  Here, in accordance with the first embodiment described above, the fuel combinations shown in Table 1 can be used as the fuel that is switched depending on whether or not the air pollutant is likely to become a high concentration. .

  In the case of the combination of high octane number gasoline and low octane number gasoline in 2 of Table 1, low octane number gasoline as the first fuel A in the first fuel container 120A and second fuel in the second fuel container 120B. High octane gasoline will be accommodated as B. In this case, for example, the fuel container 120 is configured such that the boundary between the first fuel container 120A and the second fuel container 120B is defined by the separation membrane, or, for example, Japanese Patent Laid-Open No. 2004-232624 The on-vehicle fuel separator described in 1) may be used.

  Further, as a fuel whose mixing ratio can be changed depending on whether or not the above-mentioned air pollutant is likely to become a high concentration, a combination of fuels as shown in Table 2 is possible.

  In the case of the combination of GTL and light oil in 2 of Table 2, it is effective for a diesel engine, GTL as the first fuel A in the first fuel container 120A described above, and the second in the second fuel container 120B. Light oil is accommodated as the fuel B. For normal driving, both are used at an appropriate mixing ratio, and when it is determined that the air pollutant is likely to become a high concentration, GTL, which is a fuel in a form that emits less pollutant, is used. As described above, the fuel mixing ratio is adjusted by the fuel mixing valve 114. As this adjustment, it is good also as a state which makes GTL 100% or contains some light oil.

  In addition to the fuel described above, the present invention can be applied when a combination of two or more kinds of fuels is used in a bi-fuel engine, and any one of them is a fuel that emits less pollutants. Nor. Such fuels include natural gas and petroleum gas as primary fuel, or hydrogen, coal conversion gas and petroleum conversion gas as secondary fuel, and hydrocarbons such as isooctane, hexane, heptane, kerosene as liquid fuel. Alternatively, a combination of butane, hydrocarbon such as propane, methanol, or the like that can be stored in a liquid state can be used.

1 is an overall diagram showing an embodiment of a fuel control device for a vehicle equipped with a bi-fuel engine according to the present invention. It is a flowchart which shows an example of the control routine in 1st embodiment of this invention. It is a flowchart which shows an example of the control routine in 2nd embodiment of this invention.

Explanation of symbols

100 Bi-fuel engine 112 Fuel switching valve 114 Fuel mixing valve 120 Fuel container 120A First fuel container 120B Second fuel container 130 Electronic control unit 140 Car navigation system 142 GPS antenna 144 VICS antenna 150 Outside air temperature sensor 160

Claims (4)

A vehicle with a bi-fuel engine that can use two or more types of fuel,
Air pollution status judging means for judging the air pollution status around the vehicle,
When it is determined by the air pollution status determination means that the air pollutant is likely to be high in concentration, a fuel supply system is used so as to use a fuel that emits less pollutant among the two or more types of fuel. Use fuel control means to control;
A fuel control device for a vehicle equipped with a bi-fuel engine.   2. The fuel control for a vehicle equipped with a bi-fuel engine according to claim 1, wherein the air pollution status determination unit determines based on at least position information of the own vehicle, surrounding traffic congestion information, outside air temperature information, and time information. apparatus.   The fuel control device for a vehicle with a bi-fuel engine according to claim 1, wherein the used fuel control means includes a fuel switching valve control device that switches between the two or more types of fuel. The fuel control device for a vehicle equipped with a bi-fuel engine according to claim 1, wherein the used fuel control means includes a fuel mixing valve control device that adjusts a mixing ratio of the two or more kinds of fuels.

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