JP5304298B2 - Hybrid travel control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hybrid traveling control device which can efficiently operate an engine, even if a case occurs frequently, in which an engine demanded power which is a combined power of a traveling demanding power of a driver and a charge demanding power of a battery exceeds the best mileage range of the engine. <P>SOLUTION: The traveling control device 10 which controls a hybrid vehicle 1 has: a demanding power operation means which obtains the engine demanded power which is the combined power of the traveling demanding power input from an accelerator pedal 24 and the charge demanding power of the battery; and a charge restriction means which restricts the charge demanding power of the battery when the engine demanded power obtained from the demanding power operation means exceeds the best mileage range of the engine. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a hybrid travel control device that controls a hybrid vehicle according to a travel state in a hybrid vehicle including an engine and a rotating electrical machine that operates as a motor generator.

  The hybrid vehicle travels using power from an engine that is an internal combustion engine and power from a motor generator, and converts a part of power from the engine into electric power to charge a battery. For this reason, the efficiency of the engine may change greatly due to the charging of the battery, and the fuel efficiency may become unstable. Therefore, in the hybrid vehicle of Patent Document 1, the required power is set according to the driver's accelerator operation, the battery charging power is set based on the SOC of the battery, and the sum of the two is set as the engine target power. When the engine target power is less than a predetermined lower limit value, the engine target power is set to the lower limit value, and the battery charging power is also changed to operate the engine and the motor generator. Since this lower limit is a value at which the efficiency with respect to the output of the engine becomes the optimum efficiency, the control in this way prevents operation in a low output range where the engine efficiency deteriorates.

  Further, in Patent Document 2, when there is a region where the engine efficiency is relatively low on the engine operating line, the operation point corresponding to the required output and the two operations that are switched and controlled so that the required output is maintained. A technique for efficiently operating the engine by setting the more efficient of the points as the operating point is disclosed.

JP 2004-144041 A JP 2006-170052 A

  In the hybrid vehicle according to the above-described patent document, if the sum of the required driving power required by the driver and the required charging / discharging power of the battery is equal to or less than the required power in the vicinity of the best fuel efficiency of the engine, the fuel efficiency is improved. Become. However, if the required power in the vicinity of the best fuel efficiency range of the engine is exceeded, the engine thermal efficiency is inferior to the best range, and there is room for improvement from the viewpoint of the engine use range.

  Therefore, in the present invention, even when the engine required power, which is the sum of the driver's required travel power and the battery required power, exceeds the best fuel efficiency of the engine, it is possible to run the engine efficiently. An object is to provide a control device.

A hybrid travel control apparatus according to the present invention is a battery in which a distribution relationship between an engine output and a rotating electrical machine output is determined in advance, and is charged by the rotating electrical machine. In a hybrid travel control device that obtains driving force from the vehicle and performs travel control, required power calculation means that calculates engine required power by adding the required travel power input from the accelerator pedal and the required charging power of the battery, and required power calculation If the engine required power obtained from the means exceeds the best fuel efficiency range of the engine and the required travel power exceeds the best fuel efficiency range of the engine, the required travel charge power is left as it is and the required engine power is zero. The fuel efficiency of the engine exceeds the best fuel efficiency range and the required driving power When it is less good range, engine power demand to drive power demand as it is characterized by having a charge limiting means for limiting the charge required power so that the fuel economy best region of the engine, a.
The hybrid travel control apparatus according to the present invention is a battery in which a distribution relationship between the engine output and the plurality of rotating electrical machine outputs is determined by the operation collinear characteristics of the planetary gear mechanism and is charged by at least one rotating electrical machine. to obtain a driving force from the engine along with obtaining a driving force from the rotary electric machine I by the power from the battery, the hybrid drive control apparatus that performs travel control, the drive power demand and battery charge power demand input from the accelerator pedal When the engine required power obtained from the required power calculation means exceeds the engine fuel efficiency best range and the travel demand power exceeds the engine fuel efficiency best range, The required power for driving is kept as it is and the required power for charging is set to zero. Exceeds the fuel consumption best range of emissions, and when the drive power demand is less than the fuel consumption best range of the engine, the engine power demand to limit the charging power demand such that the fuel consumption best region of the engine the drive power demand as it is charged And limiting means.

  By using the travel control device according to the present invention, the engine operates efficiently even when the engine required power, which is the sum of the driver's required travel power and the battery charge required power, exceeds the engine fuel efficiency best range. There is an effect that can be made.

It is a block diagram which shows the structure of the hybrid vehicle provided with the traveling control apparatus which concerns on embodiment of this invention. It is a characteristic view which shows an example of the operating characteristic of the engine which concerns on embodiment of this invention. It is a schematic diagram which shows the use frequency of the engine which concerns on embodiment of this invention. It is a flowchart figure which shows the flow of a process of the traveling control apparatus which concerns on embodiment of this invention.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described with reference to the drawings.

  FIG. 1 shows a configuration of a hybrid vehicle 1 provided with a travel control device 10. The hybrid vehicle 1 is divided into a power transmission system, a power transmission system, and an electrical system. The power transmission system functions as an engine 13, a power distribution mechanism 14 connected to the output shaft of the engine 13, a motor / generator MG1 (11) capable of generating electricity connected to the power distribution mechanism 14, and a power source. A motor / generator MG <b> 2 (12), a reduction gear 19 connected to the power distribution mechanism 14, and a wheel 18 connected to the reduction gear 19 are provided. The power transmission system and the electrical system include an inverter (22, 23) connected to the battery 21, a travel control device 10 that controls the inverter (22, 23) and the engine 13 according to an operation instruction from the accelerator pedal 24, A rotation sensor (15, 16, 17) for detecting the number of rotations of the engine 13 and the motor generator (11, 12) is provided.

  The power distribution mechanism 14 meshes with the sun gear (S) of the outer gear, the ring gear (R) of the internal gear arranged concentrically with the sun gear (S), and the ring gear (R). A plurality of pinion gears that mesh with each other, and a carrier (C) that holds the plurality of pinion gears so as to rotate and revolve freely. In the power distribution mechanism 14 of FIG. 1, the crankshaft of the engine 13 is connected to the carrier (C), the motor generator MG1 is connected to the sun gear (S), and the reduction gear 19 is connected to the ring gear (R). The motor generator MG2 is connected, the rotation speed of each axis is detected by the rotation sensors (15, 16, 17), and the information is sent to the travel control device 10. Motor generator MG1 (11) and motor generator MG2 (12) can be used as a generator by inverter 23 and inverter 22, and can also be used as an electric motor.

  Normally, the hybrid vehicle 1 calculates a required torque to be output to the ring gear (R), which is the drive shaft, based on the accelerator opening corresponding to the depression amount of the accelerator pedal 24 by the driver and the vehicle speed V. The engine 13, the motor generator MG1 (11), and the motor generator MG2 (12) are controlled by the travel control device 10 so that the required power corresponding to the torque is output to the ring gear (R).

  As the operation mode of the travel control device 10, a torque conversion operation mode for transmitting the output of the engine to the wheels, a charge / discharge operation mode for operation accompanied by charging / discharging of the battery, and a motor operation for stopping the engine and traveling only by the motor. There are modes.

  FIG. 2 is a characteristic diagram showing an example of the operating characteristics of the engine, where the vertical axis shows the engine torque Te, the horizontal axis shows the engine speed Te, and the axis in the depth direction shows the engine thermal efficiency η. In the figure, the equal output line P shows the relationship between the engine torque Te and the engine speed Ne when the engine output value is constant, and the equal fuel consumption rate line S (right The fuel efficiency priority operation line R is located at a higher fuel efficiency rate. The engine thermal efficiency η has a predetermined characteristic depending on the engine torque Te and the engine speed Te.

  The travel control device controls the engine torque so as to control in the region where the engine thermal efficiency η is good based on the engine operating characteristics of FIG. 2 and the engine required power obtained by adding the driver required travel power and the battery charge required power. Te and engine rotation Ne are controlled. However, since the system efficiency of the entire vehicle is the product of the engine thermal efficiency and the transmission efficiency to the wheels, the engine thermal efficiency corresponding to the control region with good system efficiency has a range. Furthermore, in the hybrid vehicle, it is necessary to charge the battery based on the SOC of the battery.

  FIG. 3 shows the frequency of use of the engine. In the figure, the vertical axis indicates the engine thermal efficiency η and the horizontal axis indicates the engine power. The engine thermal efficiency is Kmax, which is the maximum engine thermal efficiency ηmax. In the conventional control, the frequency of the region where the engine power is relatively low is high in the region where the engine power is relatively low, but there is a part where the frequency of use is high even in the region where the engine power exceeding Kmax is relatively large. I was using the bad part of. This is because, during high-speed cruise traveling, the power required for charging the battery accompanying the decrease in the SOC of the battery by compensating for the power that is insufficient for the engine output by the motor generator is accepted as it is.

  Therefore, in the travel control apparatus according to the present embodiment, in order to improve the use frequency of the section of Kmax + α considering the system efficiency in Kmax, the charge request power acceptance frequency of the battery permitted in the use range larger than Kmax + α is set. By reducing the frequency, we decided to increase the frequency of use of the best fuel efficiency of the engine. As a result of this processing, the engine usage frequency (deteriorated by conventional control) decreases in the region where the engine power of FIG. 3 is greater than Kmax + α, and the engine usage frequency from Kmax to Kmax + α (the engine usage region improvement) increases. As a result, system efficiency can be improved.

  The travel control device performs processing according to the following steps. First, (1) when the required engine power Pe exceeds the power (Kmax + α) corresponding to the vicinity of the best fuel consumption range of the engine, the required travel power Pa from the driver corresponds to the power (Kmax + α corresponding to the vicinity of the best fuel consumption range of the engine). If it is less than (), the required charging power of the battery is limited. However, (2) if the required travel power Pa from the driver is equal to or greater than the power (Kmax + α) corresponding to the vicinity of the best fuel efficiency range of the engine, the required travel power Pa is set as the required engine power. Further, (3) if the engine required power Pe is equal to or lower than the power (Kmax + α) corresponding to the vicinity of the best fuel efficiency range of the engine, the combined power of the driver required power and the battery charge / discharge required power to the engine as usual. I will order.

  FIG. 4 is a flowchart showing a process flow of the travel control device. When the processing by the travel control device 10 in FIG. 1 is started, vehicle information such as the vehicle speed, the engine speed, and the accelerator opening is sent to the travel control device 10 as parameters from a main controller (not shown) of the hybrid vehicle 1 in step S10. Entered. Next, in step S12, the required travel power Pa is calculated based on the vehicle information acquired by the travel control device 10. In step S <b> 14, travel control apparatus 10 calculates battery charge request power Pchg. Similarly, in step S16, the travel control device 10 calculates an engine required power Pe that is the sum of the travel required power Pa and the charge / discharge required power Pchg.

  Next, if the engine required power Pe is equal to or less than the power (Kmax + α) corresponding to the vicinity of the best fuel efficiency of the engine in step S18, the traveling control device 10 proceeds to the return without limiting the charge required power Pchg, and sets Kmax + α. If exceeded, the process proceeds to step S20 in order to limit the required charging power Pchg.

  If the travel request power Pa from the driver is less than the power (Kmax + α) corresponding to the vicinity of the best fuel efficiency in step S20, the travel control apparatus 10 proceeds to step S22, and the engine required power Pe corresponds to the vicinity of the best fuel efficiency range. This is limited to the power (Kmax + α).

  If the travel request power Pa from the driver is equal to or greater than the power (Kmax + α) corresponding to the vicinity of the best fuel efficiency in step S20, the travel control device 10 proceeds to step S24, and the travel request power Pa from the driver. Only the minute is output as the engine required power Pe. This is because the will of the driver is given priority.

  As described above, by using the travel control device according to the present embodiment, the engine request power obtained by adding the driver travel request power and the battery charge request power exceeds the fuel efficiency best range of the engine, By increasing the frequency of operating the engine efficiently, the efficiency of the entire system can be increased.

  The hybrid travel control apparatus according to the present invention can be used to improve the fuel efficiency of a hybrid vehicle by controlling the hybrid vehicle according to the travel state in a hybrid vehicle including an engine and a rotating electrical machine that operates as a motor generator. it can.

  DESCRIPTION OF SYMBOLS 1 Hybrid vehicle, 10 Travel control apparatus, 11, 12 Motor generator, 13 Engine, 14 Power distribution mechanism, 15, 16, 17 Rotation sensor, 18 wheels, 19 Reduction gear, 21 Battery, 22, 23 Inverter, 24 Accelerator pedal.

Claims (2)

A battery in which a distribution relationship between the engine output and the rotating electrical machine output is determined in advance and is charged by the rotating electrical machine, the driving power is obtained from the rotating electrical machine and the driving power is obtained from the engine by the electric power from the battery, and the travel control is performed. In the hybrid cruise control device to perform,
A required power calculation means for obtaining an engine required power obtained by adding the travel required power input from the accelerator pedal and the battery charge required power;
When the required engine power obtained from the required power calculation means exceeds the best fuel efficiency range of the engine , and when the required travel power exceeds the best fuel efficiency range of the engine, the required demand power is left as it is,
When the required engine power exceeds the best fuel efficiency of the engine and the required travel power is less than or equal to the best fuel efficiency of the engine, the required charging power is set so that the required engine power remains within the best fuel efficiency of the engine. Charging limiting means for limiting
A hybrid travel control device comprising: A distribution relationship between the engine output and the outputs of the plurality of rotating electrical machines is determined by the operation collinear characteristics of the planetary gear mechanism, and the battery is charged by at least one rotating electrical machine. In the hybrid travel control device that obtains driving force from the engine and performs travel control,
A required power calculation means for obtaining an engine required power obtained by adding the travel required power input from the accelerator pedal and the battery charge required power;
When the required engine power obtained from the required power calculation means exceeds the best fuel efficiency range of the engine , and when the required travel power exceeds the best fuel efficiency range of the engine, the required demand power is left as it is,
When the required engine power exceeds the best fuel efficiency of the engine and the required travel power is less than or equal to the best fuel efficiency of the engine, the required charging power is set so that the required engine power remains within the best fuel efficiency of the engine. Charging limiting means for limiting
A hybrid travel control device comprising:

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