JP2001304036A - Method for judging rotating speed of internal combustion engine and device for detecting rotating speed of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eligibly judge reliability of rotating speed of an internal combustion engine, and judge correct rotating speed of the internal combustion engine. SOLUTION: A master control unit 270 takes a crank angle engine rotating speed Necrn and cam angle engine rotating speed Necam on the basis of a crank angle signal Sne and a cylinder judging signal Sg respectively outputted from a crank position sensor 152 and a cam position sensor 155. Calculation engine rotating speed Necal is acquired from a collinear figure using rotating speed Nm1 of a motor MG1 detected by first and second motor rotating speed sensors 134, 144 and rotating speed Nm2 of a motor MG2. The master control unit 270 decides correct engine rotating speed Ne on the basis of combination of the crank angle engine rotating speed Necrn, the cam angle engine rotating speed Necam, and the calculation engine rotating seed Necal which are acquired respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for obtaining a correct rotation speed of an internal combustion engine. In addition, the present invention relates to a technique for determining an abnormality in a power transmission system using a rotation speed of an internal combustion engine.

[0002]

2. Description of the Related Art A hybrid vehicle having an internal combustion engine and an electric motor as a driving force source has been put to practical use. Among the hybrid vehicles, in a parallel type hybrid vehicle in which the required vehicle output is shared and output by the internal combustion engine and the electric motor, the internal combustion engine and the electric motor are mechanically coupled by a power split mechanism such as a planetary gear device. Therefore, the rotation speed of the internal combustion engine and the rotation speed of the electric motor have a certain relationship.
This relationship can be easily understood by showing it as a characteristic line. For example, in a hybrid vehicle having two electric motors, the rotational speed of the internal combustion engine is detected using an output signal from a crank position sensor provided on a crankshaft, and the rotational speed of the first electric motor is detected. Detected using the output signal from the resolver provided in,
The rotation speed of the second electric motor is detected using an output signal from a resolver provided on the rotation shaft of the second electric motor. The rotation speed of the internal combustion engine, the rotation speed of the first electric motor, and the rotation speed of the second electric motor thus detected satisfy the above-described relationship (characteristic line) as long as the power transmission system of the vehicle is normal. Therefore, when each of the detected rotational speeds does not satisfy the characteristic line, it has been determined that an abnormality has occurred in the power transmission system of the vehicle, for example, slippage of the torque limiter or seizure of the planetary gear.

[0003]

However, in a conventional hybrid vehicle, both the internal combustion engine speed used for engine control and the internal combustion engine speed used for referring to a characteristic line are output signals from a crank position sensor. Was detected based on Further, in a hybrid vehicle, it is necessary to always detect the internal combustion engine speed regardless of whether or not the internal combustion engine is operating in order to execute the operation control of the internal combustion engine and the electric motor. Therefore, the internal combustion engine rotation speed is required even in an extremely low rotation speed range equal to or lower than the idling rotation speed. However, a magnetic pickup sensor having a low resolution in the extremely low rotation speed region is generally used as the crank position sensor. Therefore, it is easily affected by noise and the like due to vibration of the vehicle.

[0004] If the output signal from the crank position sensor is affected by noise or the like, both rotation speeds take erroneous values, and the reliability of the obtained internal combustion engine rotation speed (whether correct or not). Could not be determined. In such a case, there has been a problem that it is not possible to obtain an accurate internal combustion engine speed, and it is not possible to accurately determine an abnormality in the power transmission system of the vehicle based on the characteristic line. Furthermore, it is determined that the rotation speeds of these motors are incorrect values, even though the rotation speeds of the internal combustion engine are incorrect and the rotation speeds of the first motor and the second motor are accurate. There was something.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and has as its object to appropriately determine the reliability of a crank angle signal of an internal combustion engine. It is another object of the present invention to determine a more accurate internal combustion engine speed. It is another object of the present invention to accurately execute the abnormality determination using a more accurate internal combustion engine speed.

[0006]

Means for Solving the Problems and Action / Effect Thereof A first aspect of the present invention for solving the above-mentioned problems is that the output is provided with the rotation of the crankshaft in a region lower than the idling speed of the internal combustion engine. A method is provided for determining the reliability of a crank angle signal. A method according to a first aspect of the present invention includes obtaining a crank angle signal, obtaining a cylinder discrimination signal output from a detection unit different from the detection unit that outputs the crank angle signal, and obtaining the obtained crank angle signal. And determining whether the acquired crank angle signal has reliability based on a combination of the acquired crank angle signal and the acquired cylinder determination signal.

According to the method according to the first aspect of the present invention,
The reliability of the crank angle signal is determined based on a combination of a cylinder discrimination signal and a crank angle signal output from a detector different from the detector that outputs the crank angle signal.
Therefore, the reliability of the crank angle signal can be appropriately determined in consideration of the influence of the erroneous detection of the detection unit.

[0008] In the method according to the first aspect of the present invention,
Comparing the rotation speed of the internal combustion engine based on the obtained crank angle signal with the rotation speed of the internal combustion engine based on the obtained cylinder discrimination signal, and when the difference between the two rotation speeds is equal to or greater than a predetermined rotation speed, It may be determined that the angle signal has no reliability. When such a configuration is provided, it is not possible to determine that the crank angle signal is abnormal, but it is possible to determine at least that the reliability of the crank angle signal is doubtful.

A second aspect of the present invention provides a method for determining the rotation speed of an internal combustion engine in a vehicle including the internal combustion engine and an electric motor. According to a second aspect of the present invention, there is provided a method for determining a first internal combustion engine speed based on a crank angle signal, and generating a first cylinder speed signal based on a cylinder discrimination signal output from a detection unit different from the detection unit for outputting the crank angle signal. A second internal combustion engine speed is calculated based on the first internal combustion engine speed based on the rotation speed of the electric motor.
The internal combustion engine speed is determined based on the second internal combustion engine speed and the third internal combustion engine speed.

According to the method according to the second aspect of the present invention,
A more accurate (reliable) internal combustion engine speed is determined based on the first, second, and third internal combustion engine speeds, so that a more accurate internal combustion engine speed is determined. The engine speed can be determined. That is, these three internal combustion engine speeds are obtained from different detection means, and do not depend on each other.

[0011] In the method according to the second aspect of the present invention,
The third internal combustion engine speed may be calculated using a characteristic line that associates the speed of the internal combustion engine with the speed of the electric motor. Further, the crank angle signal may be output as the crankshaft rotates, and the cylinder determination signal may be output as the camshaft rotates. Further, the abnormality of the drive system of the vehicle may be detected using the determined internal combustion engine speed. In the case where such a configuration is provided, it is possible to accurately execute the abnormality determination using the more accurate rotation speed of the internal combustion engine.

According to a third aspect of the present invention, a rotational speed of an internal combustion engine is detected in a vehicle in which output shafts of the internal combustion engine, a first electric motor, and a second electric motor are connected so as to influence each other. Provide equipment. An internal combustion engine rotation speed detecting device according to a third aspect of the present invention is a first internal combustion engine which is a rotation speed of the internal combustion engine based on a crank angle signal output with rotation of an output shaft of the internal combustion engine. A first internal combustion engine rotational speed calculating means for calculating a rotational speed; and a second internal combustion engine rotational speed which is a rotational speed of the internal combustion engine based on a cylinder discrimination signal output with rotation of an output shaft of the internal combustion engine. A second internal combustion engine speed calculating means for calculating, and a third speed which is a speed of the internal combustion engine based on a speed of the first electric motor.
Third internal combustion engine speed calculating means for calculating the internal combustion engine speed; and internal combustion engine speed determining means for determining the internal combustion engine speed based on the calculated first, second and third internal combustion engine speeds. It is characterized by having.

According to the internal combustion engine rotational speed detecting device according to the third aspect of the present invention, the first internal combustion engine rotational speed, the second internal combustion engine rotational speed, and the third internal combustion engine rotational speed detected by the different detecting means are different from each other. Since the more accurate internal combustion engine speed is determined based on the internal combustion engine speed, the more accurate internal combustion engine speed can be determined.

In a third aspect of the present invention, the third internal combustion engine speed calculating means includes an output shaft of the internal combustion engine, a first electric motor, and a second electric motor. Using the characteristic line relating the rotation speed, the third
The internal combustion engine speed may be calculated. The internal combustion engine includes a crankshaft as the output shaft, and a camshaft that rotates with the rotation of the crankshaft. The crank angle signal is output with the rotation of the crankshaft, and the cylinder discrimination signal May be output as the camshaft rotates. Further, there may be provided abnormality determination means for determining abnormality of the internal combustion engine and a power transmission mechanism for transmitting a driving force of the internal combustion engine using the determined rotation speed of the internal combustion engine. In the case where such a configuration is provided, it is possible to accurately execute the abnormality determination using the more accurate rotation speed of the internal combustion engine.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described based on examples in the following order. A. Overall configuration of hybrid vehicle B. B. Basic operation of hybrid vehicle J. Determination of reliability of engine speed Ne Determination of engine speed Ne

A. Overall structure of hybrid vehicle: Fig. 1
FIG. 1 is an explanatory diagram showing an overall configuration of a hybrid vehicle as one embodiment of the present invention. This hybrid vehicle has an engine 150 and two motor / generators MG1,
And MG2. Here, “motor / generator” means a motor that functions both as a motor and as a generator. In the following, these are simply referred to as “motors” for simplicity. The control of the vehicle is performed by the control system 200.

The control system 200 includes a main ECU 21
0, the brake ECU 220, and the battery ECU 230
And an engine ECU 240. Each ECU
Is configured as one unit in which a plurality of circuit elements such as a microcomputer and an input interface and an output interface are arranged on one circuit board. The main ECU 210 has a motor control unit 260 and a master control unit 270. Master control unit 270
Has a function of determining a control amount such as an output distribution of the three prime movers 150, MG1 and MG2.

Engine 150 is a normal gasoline engine, and rotates crankshaft 156 by energy generated by explosive combustion. The engine 150 will be described in detail with reference to FIG. FIG. 2 is an explanatory diagram showing selected main components closely related to the present embodiment from among the components shown in FIG. A test rotor 151 having a plurality of test pieces formed along its outer circumference is mounted on the crankshaft 156, and a crank position sensor near the test rotor 151 for detecting passage of the test piece. 152 are arranged. The crank position sensor 152 is a magnet pickup (MPU) type sensor and outputs a crank angle signal Sne as the test piece passes. In this embodiment, the test pieces are formed at intervals of 10 ° crank angle (CA), and the crank angle signal Sne is output every time the crankshaft 156 rotates 10 ° CA. Is connected to the master control unit 270, and the master control unit 270 calculates the crank angle engine speed Necrn based on the output crank angle signal Sne.

A camshaft 153 which is driven by a crankshaft 156 and which opens and closes an intake valve and an exhaust valve is disposed above the engine 150. A test rotor 154 having a test piece formed at one location on its outer periphery is mounted on the camshaft 153, and a cam position sensor 155 that detects passage of the test piece near the test rotor 154. Is arranged. The cam position sensor 155 is an MPU-type sensor and outputs a cylinder discrimination signal Sg as the test piece passes. The cylinder discrimination signal Sg is a signal indicating the timing when a specific cylinder, for example, the first cylinder reaches the compression top dead center. In the present embodiment, the cylinder discrimination signal Sg is output every 720 ° CA. The cam position sensor 155 is connected to the master control unit 270, and the master control unit 270 determines the time when the specific cylinder reaches the compression top dead center based on the output cylinder determination signal Sg. The master control unit 270 also controls the cylinder discrimination signal S
The cam angle engine speed Necam is calculated based on g.
This cam angle engine rotation speed Necam is used for determining the reliability of the crank angle engine rotation speed Necrn, and is also used as the rotation speed of the motor MG1 when performing an abnormality determination of the power transmission system using the alignment chart. Can be Note that the alignment chart will be described when describing a planetary gear.

The operation of the engine 150 is controlled by the engine ECU 2
40. Engine ECU 240
According to a command from master control unit 270, engine 15
The fuel injection amount of 0, the ignition timing, and other controls are executed.

The motors MG1 and MG2 are configured as synchronous motors, and have rotors 132 and 142 having a plurality of permanent magnets on the outer peripheral surface and stators around which three-phase coils 131 and 141 for forming a rotating magnetic field are wound. 133,143
And Stators 133 and 143 are fixed to case 119. Stator 13 of motor MG1, MG2
The three-phase coils 131 and 141 wound around 3,143 are
The battery 19 is connected via drive circuits 191 and 192, respectively.
4 is connected. The drive circuits 191 and 192 are transistor inverters each including a pair of transistors as switching elements for each phase. Drive circuit 19
1, 192 are controlled by the motor control section 260.
Drive circuit 1 according to a control signal from motor control unit 260
When the transistors 91 and 192 are switched,
Current flows between battery 194 and motors MG1 and MG2. The motors MG1 and MG2 can operate as electric motors that receive and supply power from the battery 194 and rotate (hereinafter, this operation state is referred to as power running),
When the rotors 132 and 142 are rotating by external force, the battery 194 can be charged by functioning as a generator for generating an electromotive force at both ends of the three-phase coils 131 and 141. Note that when the external force is the output of the engine 150, it is "power generation", and when the external force is the braking force, it is "regeneration". In the present embodiment, this operation state is hereinafter collectively called "regeneration".

The engine 150 and the rotating shafts of the motors MG1 and MG2 are mechanically connected via a planetary gear 120. The planetary gear 120 includes a sun gear 121.
, Ring gear 122, planetary pinion gear 12
And a planetary carrier 124 having the number three. In the hybrid vehicle of the present embodiment, the engine 1
The 50 crankshafts 156 are connected to a planetary carrier shaft 127 via a damper 130. The damper 130 is provided to absorb torsional vibration generated in the crankshaft 156. Rotor 1 of motor MG1
32 is connected to the sun gear shaft 125. In the vicinity of the sun gear shaft 125, a first motor rotation speed sensor 134 for detecting the rotation speed of the motor MG1 is arranged. The rotor 142 of the motor MG2 is
6. Near the ring gear shaft 126, a second motor speed sensor 144 for detecting the speed of the motor MG2 is arranged. The rotation of the ring gear 122 is controlled by the chain belt 129 and the differential gear 1.
14 and an axle 112 and wheels 116R, 116
L.

The control system 200 uses various sensors to realize the control of the whole vehicle. For example, an accelerator sensor 165 for detecting an amount of depression of an accelerator by a driver, and a position of a shift lever are detected. Shift position sensor 167, brake sensor 163 for detecting brake depression pressure, battery 194
A battery sensor 196, a first motor rotation speed sensor 134, a second motor rotation speed sensor 144, and the like for detecting the state of charge of the battery are used. Ring gear shaft 126
And the axle 112 are mechanically connected by the chain belt 129, so that the ring gear shaft 126 and the axle 112
Are constant. Therefore, the ring gear shaft 12
6 can detect not only the rotation speed of the motor MG2 but also the rotation speed of the axle 112.

B. Basic operation of hybrid vehicle: In order to explain the basic operation of the hybrid vehicle, first, the operation of the planetary gear 120 will be described below. The planetary gear 120 has such a property that when the rotation speed of two of the three rotation shafts is determined, the rotation speed of the remaining rotation shafts is determined. The relationship between the number of rotations of each rotating shaft is as in the following equation (1).

Nc = Ns × ρ / (1 + ρ) + Nr × 1 / (1 + ρ) (1) where Nc is the number of rotations of the planetary carrier shaft 127,
Ns is the rotation speed of the sun gear shaft 125, and Nr is the rotation speed of the ring gear shaft 126. Ρ is a gear ratio between the sun gear 121 and the ring gear 122 as represented by the following equation.

Ρ = [number of teeth of sun gear 121] / [number of teeth of ring gear 122] Here, the alignment chart will be described with reference to FIG. FIG.
Is an explanatory diagram showing an alignment chart. Engine 1 as described above
50, the rotor 132 of the motor MG1 and the rotor 142 of the motor MG2 are respectively connected to the carrier shaft 127 and the sun gear shaft 12 of the planetary gear 120.
5. It is connected to the ring gear shaft 126. Therefore, the engine rotation speed Ne, the rotation speed Nm1 of the motor MG1,
And the rotational speed Nm2 of the motor MG2 are related by the collinear characteristic of the planetary gear shown in the above equation (1). A graph visualizing this collinear characteristic is a collinear diagram, in which the vertical axis represents the rotational speed, and the horizontal axis represents the rotational speed Nm1 of the motor MG1, the engine rotational speed Ne, and the rotational speed Nm2 of the motor MG2. It is arranged in. As is apparent from the above equation (1), all the rotational speeds must be connected in a straight line on this alignment chart.

The torques of the three rotating shafts have a fixed relationship given by the following equations (2) and (3), regardless of the number of rotations.

Ts = Tc × ρ / (1 + ρ) (2) Tr = Tc × 1 / (1 + ρ) = Ts / ρ (3) where Tc is the torque of the planetary carrier shaft 127,
Ts is the torque of the sun gear shaft 125, and Tr is the torque of the ring gear shaft 126.

The hybrid vehicle of this embodiment can run in various states by the function of the planetary gear 120. For example, in a relatively low-speed state in which the hybrid vehicle has started running, the motor MG2 is powered while the engine 150 is stopped, so that the axle 11
2 to transmit power. Similarly, the vehicle may travel with the engine 150 idling.

When the hybrid vehicle reaches a predetermined speed after the start of traveling, the control system 200 powers the motor MG1 to start the engine 150 by motoring with the output torque. At this time, the reaction torque of the motor MG1 is transmitted to the ring gear 12 via the planetary gear 120.
2 is also output.

When the engine 150 is operated to rotate the planetary carrier shaft 127, the sun gear shaft 125 and the ring gear shaft 126 rotate under the conditions satisfying the above equations (1) to (3). The power generated by the rotation of the ring gear shaft 126 is transmitted to the wheels 116R and 116L as they are. The power by the rotation of the sun gear shaft 125 is supplied to the first motor MG1.
And can be regenerated as electric power. On the other hand, by powering the second motor MG2, power can be output to the wheels 116R and 116L via the ring gear shaft 126.

At the time of steady operation, the output of engine 150 is set to a value substantially equal to the required power of axle 112 (ie, the number of revolutions of axle 112 × torque). At this time,
Part of the output of engine 150 is transmitted directly to axle 112 via ring gear shaft 126, and the remaining output is regenerated as electric power by first motor MG1. The regenerated electric power is used by second motor MG2 to generate torque for rotating ring gear shaft 126. As a result, it is possible to drive the axle 112 at a desired rotation speed with a desired torque.

When the torque transmitted to the axle 112 is insufficient, the torque is assisted by the second motor MG2. As the power for this assist, the power regenerated by the first motor MG1 and the power stored in the battery 149 are used. Thus, the control system 200
Controls the operation of the two motors MG1 and MG2 according to the required power to be output from the axle 112.

The hybrid vehicle of this embodiment can also move backward while the engine 150 is running. When the engine 150 is operated, the planetary carrier shaft 127
Rotates in the same direction as when moving forward. At this time, when the first motor MG1 is controlled to rotate the sun gear shaft 125 at a higher rotation speed than the rotation speed of the planetary carrier shaft 127,
As is apparent from the above equation (1), the ring gear shaft 126 reverses in the reverse direction. The control system 200 can control the output torque of the second motor MG2 while rotating the second motor MG2 in the reverse direction, and move the hybrid vehicle backward.

The planetary gear 120 is a ring gear 12
With the 2 stopped, the planetary carrier 124 and the sun gear 121 can be rotated. Therefore, engine 150 can be operated even when the vehicle is stopped. For example, when the remaining capacity of the battery 194 is low, the engine 150 is operated and the first motor MG
The battery 194 can be charged by regenerating the battery 1. If the first motor MG1 is powered when the vehicle is stopped, the torque
50 can be motored and started.

C. Determination of Reliability of Engine Speed Ne Next, referring to FIGS. 2 and 4, the engine speed Ne will be described.
An example of the means for determining the reliability of the information will be described. FIG. 4 is a flowchart showing a processing routine executed when determining the reliability of the engine speed Ne.

This processing routine is executed at predetermined time intervals, and when the master control section 270 starts this processing routine, it waits for generation of the crank angle signal Sne (step S).
100: No). When detecting the generation of crank angle signal Sne (step S100: Ye)
s) It is determined whether or not the cylinder discrimination signal Sg has been generated during 720 ° CA (step S110). When it is determined that the cylinder determination signal Sg has been generated (step S110: Yes), the master control unit 270 determines that the crank angle engine speed Necrn calculated based on the crank angle signal Sne is correct (step S120). ), The crank angle engine speed Necrn is used as the engine speed Ne (step S130). Here, the sampling of each signal is executed, for example, for 5 seconds. That is, if the rotation speed of the crankshaft 156 is 120 rpm, the crankshaft 156 rotates 10 times in 5 seconds, and it is necessary to sufficiently determine whether or not the crank angle signal Sne is constantly output. Can be.

On the other hand, when it is determined that the cylinder determination signal Sg has not been generated (step S110: No), the master control unit 270 determines that the crank angle engine speed Necrn is not correct (step S140). Calculation engine speed Nec calculated using the output signals from the first and second motor speed sensors 134 and 144 and the alignment chart.
al is used as the engine speed Ne (step S1).
50). Master control unit 270 performs abnormality determination of the power transmission system using the determined engine speed Ne.

Here, the reason why the cylinder discrimination signal Sg is used to determine the certainty of the crank angle signal Sne will be described with reference to FIGS. FIG. 5 shows the crank angle signal S
FIG. 4 is an explanatory diagram showing a relationship between a crank angle signal Sne and a cylinder discrimination signal Sg when ne is based on noise. FIG. 6 is an explanatory diagram showing the relationship between the crank angle signal Sne and the cylinder discrimination signal Sg when the crank angle signal Sne is based on the passage of the test piece.
Since the sensors 152 and 155 that output the crank angle signal Sne and the cylinder discrimination signal Sg are MPU sensors as described above, noise is easily picked up particularly in an extremely low turning point region where the rotation speed of the test rotor decreases. . For example, engine 15
Even in the case where 0 is in a stopped state, noise may be output due to a change in magnetic flux density caused by vibration of the vehicle. In particular, the crank position sensor 15
2 outputs the crank angle signal Sne at a relatively short interval of 10 ° CA, so that the master control unit 270 may not be able to distinguish the noise from the normal crank angle signal Sne.

On the other hand, the cylinder discrimination signal Sg is 72
Since the signal is output at every 0 ° CA, even if noise due to vibration is output, master control unit 270 can easily determine whether the signal is noise or normal cylinder determination signal Sg. For example, as shown in FIG. 5, even when the crank angle signal Sne is output, if the cylinder discrimination signal Sg is not output, the output crank angle signal Sne is a noise caused by vibration of the vehicle. Is extremely high, and the master control unit 270 can determine that the crank angle engine speed Necrn lacks reliability. On the other hand, when both the crank angle signal Sne and the cylinder discrimination signal Sg are output as shown in FIG. 6, the master control unit 270 can determine that the crank angle engine speed Necrn has reliability. .

D. Determination of Engine Speed Ne Next, means for determining the correct (more likely) engine speed Ne will be described with reference to FIGS. 2, 7 and 8. FIG. 7 is a flowchart showing a processing routine executed when determining the engine speed Ne. FIG. 8 is an explanatory diagram for explaining the effect of this embodiment on a nomographic chart.

The master controller 270 acquires the crank angle engine speed Necrn and the cam angle engine speed Necam based on the crank angle signal Sne and the cylinder discrimination signal Sg output from the crank position sensor 152 and the cam position sensor 155, respectively. I do. Further, the rotation speed Nm1 of the motor MG1 and the motor M1 detected by the first and second motor rotation speed sensors 134 and 144, respectively.
Using the rotational speed Nm2 of G2, the operation engine rotational speed Necal is obtained from the alignment chart (step S200). The master control unit 270 determines the acquired crank angle engine speed Necrn
It is determined whether or not the absolute value of the difference between the cam angle and the cam angle engine speed Necam is equal to or smaller than a predetermined determination difference ΔN (step S21)
0). The determination difference ΔN is, for example, 10 to 20 rpm. The master control unit 270 calculates the crank angle engine speed Necrn and the cam angle engine speed Nec instead of taking the difference.
It may be determined whether or not am substantially coincides (Necrn ≒ Necam).

The master control unit 270 calculates | Necrn-Necam
If it is determined that | ≦ ΔN (step S21
0: Yes), it is determined to use the crank angle engine speed Necrn as the engine speed Ne (step S220). Master control unit 270 determines the determined engine speed Ne (that is, the crank angle engine speed Nec).
rn) is used to determine whether the power transmission system is abnormal (step S230). On the other hand, master control unit 270
When it is determined that −Necam |> ΔN (step S210: No), it is determined whether the absolute value of the difference between the crank angle engine speed Necrn and the calculated engine speed Necal is equal to or smaller than a predetermined determination difference ΔN (step S210). Step S240).
Instead of taking the difference, master control unit 270 may determine whether or not crank angle engine speed Necrn and calculated engine speed Necal substantially match (Necrn ≒ Necal).

The master control unit 270 calculates | Necrn-Necal
If it is determined that | ≦ ΔN (step S24
0: Yes), it is determined that the crank angle engine speed Necrn is correct, and it is determined to use the engine speed Ne as the engine speed Ne (step S250). The master control unit 270
Using the determined engine speed Ne (that is, the crank angle engine speed Necrn), the abnormality determination of the power transmission system is executed (step S230). On the other hand, the master control unit 2
70, when it is determined that | Necrn-Necal |> ΔN (step S240: No), the absolute value of the difference between the cam angle engine speed Necam and the calculation engine speed Necal is equal to or smaller than the predetermined determination difference ΔN. It is determined whether there is (Step S260). The master control unit 270 may determine whether or not the crank angle engine speed Necam and the calculated engine speed Necal substantially match (Necam ≒ Necal) instead of taking the difference.

The master control unit 270 calculates | Necam-Necal
If it is determined that | ≦ ΔN (step S26
0: Yes), it is determined that the cam angle engine speed Necam is correct, and it is determined that the cam angle engine speed Necam is to be used as the engine speed Ne (step S270). Master control unit 270 performs an abnormality determination of the power transmission system using the determined engine speed Ne (that is, cam angle engine speed Necam) (step S230). On the other hand, the master control unit 270
If it is determined that | Necam-Necal |> ΔN (step S260: No), the crank angle engine speed Necrn does not match the cam angle engine speed Necam,
Also, since neither the engine speed Necrn nor Necam matches the calculated engine speed Necal, the engine 1
It is determined that some abnormality has occurred in 50 (step S280). As the processing after the abnormality determination, for example, notification such as blinking of a warning lamp may be executed.

In the abnormality determination using the determined engine speed Ne, for example, when the crank angle engine speed Necrn is substantially equal to the cam angle engine speed Necam (the determination difference ΔN is smaller than ΔN), Under the condition that the angular engine speed Necrn is used as the engine speed Ne, the calculated engine speed Necal is the engine speed Ne.
If it is different from the above, it can be determined that the torque limiter is slipping.

As described above, according to the apparatus for determining the engine speed according to the present embodiment, the cylinder discrimination signal Sg used for controlling the operation of the engine 150 is used.
The reliability of the crank angle signal Sne can be determined without providing a new sensor. Also, the cylinder discrimination signal Sg
Is output by a cam position sensor 155 that is different from the crank position sensor 152 that outputs the crank angle signal Sne, and its output signal waveform is significantly different from the output signal waveform of the crank angle signal Sne, so that it is appropriate and relatively easy. The reliability of the crank angle signal Sne can be determined.

Further, in this embodiment, the correct engine speed Necrn is obtained by using the crank angle engine speed Necrn, the cam angle engine speed Necam, and the calculated engine speed Necal acquired based on the output signals from the different sensors. Is determined, it is possible to execute a highly accurate determination. That is, in the present embodiment, signals related to the rotation of the engine 150 are directly acquired by different detection means of the crank position sensor 152 and the cam position sensor 155, and the acquired signals are compared. Further, it is determined whether the engine speed Necrn and Necam based on which signal is correct, that is, whether the engine speed Ne should be used as the correct engine speed Ne, using the calculated engine speed Necal. Therefore, it is possible to avoid a situation in which an erroneous abnormality is determined using an erroneous index. Note that the term “correct” used in the present embodiment means not only objective and absolute correctness but also the most probable state under given conditions.

On the other hand, conventionally, an engine ECU is provided based on a signal output from a crank position sensor.
And the main ECUs respectively have engine speeds N1, N
For example, the engine speed N2 (“Inaccurate Ne” in the figure) is used for determining the abnormality of the power transmission system without obtaining the engine speed N2 and verifying the reliability of the engine speeds N1 and N2. As a result, as shown in FIG.
Is not on the collinear line, the engine speed N
2 is incorrect and the calculated engine speed Necal calculated based on the motor speed is correct.
The situation where one of the two motors is determined to be abnormal could not be excluded.

Although the apparatus for determining the rotational speed of an internal combustion engine according to the present invention has been described based on the embodiments, the above embodiments of the present invention are intended to facilitate understanding of the present invention. It does not limit the invention. The present invention may be modified without departing from the spirit and scope of the claims.
Of course, improvements can be made and the invention includes its equivalents.

In the above-described embodiment, the cam position sensor 155 is used as the means for detecting the cylinder discrimination signal Sg. However, the rotor 151 mounted on the crankshaft 156 is provided with missing teeth for cylinder discrimination, and the crank position is determined. An MPU sensor is provided separately from the sensor 152 to provide a cylinder discrimination signal S
g may be detected. If the value related to the rotation of the engine 150 can be detected from different sensors, the effect of the present embodiment can be obtained.

Further, when determining the reliability of the engine speed Ne, the crank angle signal Sne and the cylinder determination signal Sg
, But in addition to this,
For example, a determination may be made as to whether or not the crank angle signal Sne is output constantly for 5 seconds. As described above, the rotation speed of the crankshaft 156 is set to 120 r.
pm, but the crankshaft 156
When the crank angle signal Sne is constantly detected for 5 seconds, the possibility that the crank angle signal Sne is output without being caused by noise increases. In such a case, the determination accuracy can be further improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an overall configuration of a hybrid vehicle as an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing selected main components closely related to the embodiment from among the components shown in FIG. 1;

FIG. 3 is an explanatory diagram showing a nomographic chart.

FIG. 4 is a flowchart showing a processing routine executed when determining the reliability of the engine speed Ne.

FIG. 5 is an explanatory diagram showing the relationship between the crank angle signal Sne and the cylinder discrimination signal Sg when the crank angle signal Sne is based on noise.

FIG. 6 is an explanatory diagram showing the relationship between the crank angle signal Sne and the cylinder discrimination signal Sg when the crank angle signal Sne is based on the passage of a test piece.

FIG. 7 is a flowchart illustrating a processing routine that is executed when determining the engine speed Ne.

FIG. 8 is an explanatory diagram for explaining an effect of the present embodiment on a nomographic chart.

[Explanation of symbols]

 112 ... axle 114 ... differential gear 116R, 116L ... wheel 119 ... case 120 ... planetary gear 121 ... sun gear 122 ... ring gear 123 ... planetary pinion gear 124 ... planetary carrier 125 ... sun gear shaft 126 ... ring gear shaft 127 ... planetary carrier shaft 129 ... chain belt 130 ... Damper 131 ... Three-phase coil 132 ... Rotor 133 ... Stator 134 ... First motor rotation speed sensor (rotation angle sensor) 141 ... Three-phase coil 142 ... Rotor 143 ... Stator 144 ... Second motor rotation speed sensor (rotation angle sensor) 149 ... Battery 150 ... Engine 151 ... Tested rotor 152 ... Crank position sensor 153 ... Cam shaft 154 ... Tested rotor 155 ... Cam position sensor 156 ... Crankshaft Shift 163 ... Brake sensor 165 ... Accelerator sensor 167 ... Shift position sensor 191,192 ... Drive circuit 194 ... Battery 196 ... Battery sensor 200 ... Control system 210 ... Main ECU 220 ... Brake ECU 230 ... Battery ECU 240 ... Engine ECU 260 ... Motor Control unit 270: Master control unit

Claims (10)

[Claims] 1. A method for determining the reliability of a crank angle signal output with rotation of a crankshaft in a region lower than an idling rotation speed of an internal combustion engine, comprising: obtaining a crank angle signal; A cylinder discrimination signal output from a detection unit different from the detection unit that outputs the obtained crank angle signal is obtained based on a combination of the obtained crank angle signal and the obtained cylinder discrimination signal. A method of determining whether or not to have. 2. The method according to claim 1, wherein a rotation speed of the internal combustion engine based on the obtained crank angle signal is compared with a rotation speed of the internal combustion engine based on the obtained cylinder discrimination signal. If the difference between the numbers is equal to or greater than a predetermined number of revolutions, the crank angle signal is determined to be unreliable. 3. A method for determining a rotation speed of an internal combustion engine in a vehicle including an internal combustion engine and an electric motor, comprising: determining a first rotation speed of the internal combustion engine based on a crank angle signal; and outputting the crank angle signal. Calculating a second internal combustion engine rotation speed based on a cylinder discrimination signal output from a detection device different from the detection device; calculating a third internal combustion engine rotation speed based on the rotation speed of the electric motor; A method for determining an internal combustion engine speed based on an internal combustion engine speed, the second internal combustion engine speed, and the third internal combustion engine speed. 4. The method according to claim 3, wherein the third internal combustion engine speed is calculated using a characteristic line that associates the internal combustion engine speed with the electric motor speed. Method. 5. The method according to claim 3, wherein the crank angle signal is output with rotation of a crankshaft, and the cylinder discrimination signal is output with rotation of a camshaft. And how. 6. The method of claim 5, further comprising:
A method for detecting an abnormality in a drive system of the vehicle using the determined internal combustion engine speed. 7. An apparatus for detecting a rotation speed of an internal combustion engine in a vehicle in which output shafts of an internal combustion engine, a first electric motor, and a second electric motor are connected so as to influence each other. First internal combustion engine speed calculating means for calculating a first internal combustion engine speed, which is a speed of the internal combustion engine, based on a crank angle signal output with rotation of an output shaft of the engine; and an output of the internal combustion engine. Second internal combustion engine speed calculating means for calculating a second internal combustion engine speed, which is a speed of the internal combustion engine, based on a cylinder discrimination signal output with the rotation of the shaft; and a speed of the first electric motor. A third internal combustion engine rotational speed calculating means for calculating a third internal combustion engine rotational speed which is a rotational speed of the internal combustion engine based on the first and second internal combustion engine rotational speeds based on the calculated first, second and third internal combustion engine rotational speeds. Internal combustion determines engine speed An engine speed detecting device for an internal combustion engine, comprising: engine speed determining means. 8. The rotation speed detecting device for an internal combustion engine according to claim 7, wherein said third rotation speed calculating means for said internal combustion engine rotates said output shaft of said internal combustion engine, said first electric motor and said second electric motor. An engine speed detection device for an internal combustion engine, wherein the third engine speed is calculated using a characteristic line in which the numbers are associated. 9. The internal combustion engine according to claim 7, wherein the internal combustion engine includes a crankshaft as the output shaft, and a camshaft that rotates with the rotation of the crankshaft. Wherein the crank angle signal is output as the crankshaft rotates, and the cylinder discrimination signal is output as the camshaft rotates. 10. A power transmission for transmitting a driving force of the internal combustion engine and the internal combustion engine using the determined rotation speed of the internal combustion engine, further comprising the rotational speed detection device for an internal combustion engine according to claim 9. An internal-combustion-engine rotational-speed detecting device provided with abnormality determining means for determining an abnormality of a mechanism.