JP2004233223A - Testing device of prime mover - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for performing a highly accurate test by suppressing abnormality generation in a torque sensor, in a testing device for performing a test of a prime mover by realizing a state where the prime mover is loaded simulatively on a vehicle by connecting a dynamometer to the prime mover to apply a load torque. <P>SOLUTION: The dynamometer 20 is connected to an engine 10 through a shaft 30. The torque sensor 40 is provided on the output shaft of the dynamometer 20. The torque sensor 40 is protected from the heat or vibration of the engine 10 by providing the torque sensor 40 on the dynamometer 20 side. A control device 70 calculates a target load torque based on a dynamic characteristic model of the vehicle, models a control system as a three-mass inertial system when controlling the dynamometer 20 based on the load torque detected by the torque sensor 40 and the target load torque, and controls so that the load torque applied to the engine 10 becomes the target load torque. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, a load torque is applied to a prime mover such as an engine or an electric motor used as a drive source of a vehicle, so that the prime mover is equivalently (or simulated) in a state of being mounted on the vehicle. The present invention relates to a test device of a motor for performing a test.
[0002]
[Prior art]
Various tests on the output characteristics, fuel consumption characteristics, or exhaust gas characteristics of a vehicle prime mover are generally performed with the prime mover actually mounted on a vehicle. However, the test results obtained in this way only correspond to the combination of the prime mover and the vehicle equipped with the prime mover.For example, when the weight of the vehicle or the specifications of the drive system are changed, It is necessary to mount the prime mover on the new vehicle again and conduct the test. In addition, such a test method also requires a space for the vehicle.
[0003]
Therefore, instead of actually mounting the prime mover on the vehicle, a dynamometer is connected to the prime mover, and a load torque is applied from the dynamometer to the prime mover, so that the prime mover is actually mounted on the vehicle. A test apparatus has been proposed which simulates a simple state and tests the prime mover in this state.
[0004]
FIG. 5 shows a configuration of a conventional test apparatus. This test apparatus performs various tests by transmitting the torque generated by the dynamometer 20 to the engine 10 via the shaft 30 to put the engine 10 in a load state simulated on a vehicle.
[0005]
The engine 10 and the dynamometer 20 are fixed on a bench adjacent to each other so that the crankshaft 11 and the input shaft 21 are located coaxially. The ends of the crankshaft 11 and the input shaft 21 are connected to ends of the shaft 30 via couplings 31 and 32, respectively.
[0006]
The test device has a control device 70 having an engine control unit 50 for controlling the output of the engine 10 and a dynamometer control unit 60 for controlling the torque generated in the dynamometer 20.
[0007]
The engine control unit 50 adjusts the output of the engine 10 so that the virtual speed of the vehicle calculated by the dynamometer control unit 60 changes according to a predetermined vehicle speed pattern. The output is adjusted by adjusting the opening of a throttle valve 14 provided in the intake passage 12 of the engine 10 by a throttle motor 15.
[0008]
Detection signals from various sensors that detect the operating state of the engine 10 are input to the dynamometer control unit 60. The crankshaft 11 is provided with a torque sensor 40 for detecting a torque transmitted from the dynamometer 20 to the engine 10. In the vicinity of the crankshaft 11, a rotation speed sensor 42 for detecting the rotation speed of the crankshaft 11, that is, the rotation speed of the engine 10, is provided. Further, a throttle sensor 44 for detecting the throttle opening is provided near the throttle valve 14.
[0009]
The dynamometer control unit 60 calculates a load torque (target load torque) to be generated on the dynamometer 20 based on the detection signals input from these sensors and a dynamic characteristic model of the vehicle on which the engine 10 is mounted. Then, the dynamometer control unit 60 performs feedback control of the dynamometer 20 so that the calculated target load torque matches the actual torque detected by the torque sensor 40.
[0010]
FIG. 6 shows a conceptual diagram of a dynamic characteristic model of a vehicle. The vehicle is divided into a first component M1 including a torque converter and a transmission, a second component M2 including a transmission and a differential gear, a third component M3 including wheels and tires, and a fourth component M4 including a body. Model.
[0011]
In the figure, "Je" is the equivalent inertia of the engine 10, "J1" to "J3" are the equivalent inertia of each of the components M1 to M3, "K1" and "K2" are the equivalent spring constants of the components M1 and M2, " “C1” and “C2” are equivalent damping constants of the constituents M1 and M2, and are model constants identified based on experiments, design values, and the like.
[0012]
“T” is the torque ratio of the torque converter, “nt” is the reduction ratio of the transmission, and “nd” is the reduction ratio of the differential gear, which is a preset constant value. These parameters are, in terms of dynamic characteristics, sequentially, the transmission torque transmitted from the engine 10 to the first component M1, the transmission torque transmitted from the first component M1 to the second component M2, and the second component M2 from the second component M2. These are model constants for setting the transmission torque transmitted to the three components M3.
[0013]
Further, “k” is the ratio of the transmission torque transmitted from the first component M1 to the second component M2 in terms of dynamic characteristics, and corresponds to the ratio of the input / output torque of the transmission in an actual vehicle. , Are model constants for evaluating the transient torque transmission characteristics during the shift timing of the transmission.
[0014]
The dynamometer control unit 60 calculates the target load torque by inputting the rotational speed of the engine 10 into the simultaneous equations based on such a dynamic characteristic model and solving each equation of motion at a predetermined calculation cycle. The construction and calculation of the equation of motion based on the dynamic characteristic model can be executed using control simulation software.
[0015]
Note that a configuration has also been proposed in which the torque sensor 40 is not provided on the crankshaft 11 of the engine 10 but is directly connected to the operating shaft of the dynamometer 20 as a dynamometer.
[0016]
[Patent Document 1]
JP 2000-105172 A [Patent Document 2]
JP-A-7-333108
[Problems to be solved by the invention]
Since the control target of the test apparatus, that is, the target to which the load torque is applied is the drive shaft of the engine 10, the provision of the torque sensor 40 on the crankshaft 11 of the engine 10 enables the actual load torque to be detected with high accuracy. However, if the torque sensor 40 is provided on the crankshaft 11, the coolant of the engine 10 adheres to the torque sensor 40 and causes an abnormality in the torque sensor 40, or an error occurs when the engine 10 is attached to or detached from a test device. The torque sensor 40 may fall, or the torque sensor 40 may be subjected to physical damage exceeding the permissible limit of the torque sensor 40 due to heat or vibration from the engine 10 to cause problems in the torque sensor 40.
[0018]
On the other hand, by providing the torque sensor 40 on the dynamometer 20 side, such a problem can be avoided. However, in this case, the torque sensor 40 is precisely the crankshaft 11 of the engine 10 to be controlled. However, since it does not detect the load torque at the time, there arises a problem that highly accurate control cannot be performed.
[0019]
SUMMARY OF THE INVENTION An object of the present invention is to provide a test apparatus for a prime mover capable of performing a highly accurate control to test a prime mover while solving various problems caused by providing a torque sensor near an engine.
[0020]
[Means for Solving the Problems]
The present invention provides a load torque applying means for applying a load torque to a drive shaft of the vehicle prime mover via a coupling shaft connected to a drive shaft of the vehicle prime mover, and the load torque applied by the load torque apply means. Is applied based on a dynamic characteristic model using model constants such as an equivalent inertia, an equivalent damping constant, and an equivalent spring constant of a drive system including a transmission connected to the prime mover, and load torque detecting means for detecting the magnitude of And a control means for calculating a desired load torque to be applied and controlling the load torque application means based on a difference from the actual load torque detected by the load torque detection means, The torque detecting means is provided between the coupling shaft and the load torque applying means, and the control means is provided at a position of the load torque detecting means. Flip the desired load torque to control the load torque applying means to be applied to the drive shaft of the prime mover. By providing the load torque detecting means not in the vicinity of the prime mover but in a position separated from the prime mover, that is, between the coupling shaft and the load torque applying means, for example, on the output shaft of the load torque, it is possible to solve the problem in the case where it is provided in the vicinity of the prime mover. However, by providing the load torque detecting means between the coupling shaft and the load torque applying means, the load torque detected by the load torque detecting means is different from the load torque applied to the prime mover which is the original control target. Will be. Therefore, taking into account that the load torque detected by the load torque detecting means is different from the load torque applied to the prime mover, the load torque applying means is set so that the load torque applied to the prime mover becomes a desired load torque. By performing the control, it is possible to suppress the occurrence of an abnormality in the load torque detecting means and to perform a highly accurate test of the prime mover.
[0021]
In the present invention, the control means controls the load torque application means such that the desired load torque is applied to a drive shaft of the prime mover using the load torque detection means and model characteristics of the coupling shaft. Is preferred. The difference between the load torque detected by the load torque detecting means and the load torque actually applied to the prime mover is defined based on the model characteristics of the load torque detecting means and the coupling shaft. The correction amount of the load torque to be generated is determined.
[0022]
Further, the control means models a control system including the prime mover, the load torque detecting means and the load torque applying means, wherein the prime mover and the load torque detecting means are modeled as a three-mass inertial system elastically coupled by the coupling shaft. Preferably, the load torque applying means is controlled so that the desired load torque is applied to the drive shaft of the prime mover. When the load torque detecting means is provided on the prime mover side, the control means can model the control system as a two-mass inertial system in which the prime mover and the load torque applying means are connected by a coupling shaft. When provided between the coupling shaft and the additional torque applying means, the difference between the load torque detected by the load torque detecting means and the load torque of the prime mover is modeled as a three-mass inertial system instead of a two-mass inertial system. In consideration of the above, the load torque applying means can be controlled. In the three-mass inertial model, the load torque detected by the load torque detecting means is detected to be higher than the load torque of the prime mover, that is, the load torque detected by the load torque is controlled to be a desired load torque. Then, the load torque of the prime mover is less than the desired load torque. Accordingly, the load torque of the prime mover is made to coincide with a desired load torque by controlling the load torque applying means so as to eliminate the shortage and correcting the load torque generated from the load torque applying means upward.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings, taking an engine as an example of a prime mover.
[0024]
FIG. 1 shows a configuration diagram of a test apparatus according to the present embodiment. The basic configuration is the same as that of the test apparatus shown in FIG. That is, the engine 10 and the dynamometer 20 are fixed on the bench 1 adjacent to each other so that the crankshaft 11 and the input shaft 21 are located coaxially. The ends of the crankshaft 11 and the input shaft 21 are connected to ends of the shaft 30 via couplings 31 and 32, respectively. The shaft 30 has high rigidity and low inertia, and is made of, for example, a carbon material.
[0025]
In addition, the test device includes a control device 70 having an engine control unit for controlling the output of the engine 10 and a dynamometer control unit for controlling the torque generated by the dynamometer 20.
[0026]
The engine control unit adjusts the output of the engine 10 so that the virtual speed of the vehicle calculated by the dynamometer control unit changes according to a predetermined vehicle speed pattern. That is, similarly to the configuration shown in FIG. 5, the output is adjusted by adjusting the opening degree of the throttle valve provided in the intake passage of the engine 10 by the throttle motor.
[0027]
On the other hand, detection signals from various sensors that detect the operating state of the engine 10 are input to the dynamometer control unit. The dynamometer control unit generates a load torque (target load torque) to be generated by the dynamometer 20 based on the detection signals input from these sensors and a dynamic characteristic model (see FIG. 6) of the vehicle on which the engine 10 is mounted. calculate. That is, the model constants (Je, J1 to J3, M1 to M3, and the like) in the dynamic characteristic model of the vehicle shown in FIG. By substituting the equations of motion for M1 to M3 and solving each of the equations of motion at a predetermined calculation cycle, a target load torque according to the modeled running state of the vehicle is calculated. Then, the dynamometer control unit of the control device 70 performs feedback control of the dynamometer 20 based on the calculated target load torque and the torque detected by the torque sensor 40.
[0028]
Here, in the test apparatus shown in FIG. 5, the torque sensor 40 for detecting the torque transmitted from the dynamometer 20 to the engine 10 is provided on the crankshaft 11, but in the present embodiment, the torque sensor 40 Is provided on the output shaft of the dynamometer 20. Thus, by providing the torque sensor 40 on the dynamometer 20 side instead of the engine 10 side, it is possible to prevent the engine coolant from adhering, dropping when the engine 10 is attached / detached, or generating an abnormality due to the influence of heat or vibration of the engine 10. Can be avoided.
[0029]
On the other hand, when the torque sensor 40 is provided on the dynamometer 20 to detect the load torque, the detected load torque is not the load torque on the crankshaft of the engine 10 to be controlled, but the output shaft of the dynamometer 20. And the two do not exactly match. Therefore, based on the difference between the load torque value detected by the torque sensor 40 and the target load torque calculated based on the dynamic characteristic model of the vehicle, the detected load torque matches the target load torque as in the related art. In a configuration in which feedback control is performed, accurate control cannot be performed. In such feedback control, although the load torque at the installation position of the torque sensor 40 matches the target load torque, the load torque does not become the target load torque at the position of the crankshaft (crankshaft end face) of the engine 10, which is the target of control. Because.
[0030]
Therefore, in the present embodiment, it is assumed that the load torque detected by the torque sensor 40 is different from the load torque applied to the crankshaft of the engine 10 to be controlled, and the dynamometer is corrected so as to correct this difference. 20 is controlled.
[0031]
FIG. 2 shows a control system of the present embodiment. FIG. 2A is a diagram in which the engine 10, the shaft 30, the torque sensor 40, and the dynamometer 20 are extracted from the test device of FIG. 1, and FIG. 2B is a model diagram of FIG. 2A. In the test device shown in FIG. 5, since the torque sensor 40 is provided on the crankshaft of the engine 10, the torque sensor 40 is modeled as a two-mass inertial system in which the engine 10 and the dynamometer 20 are connected by the shaft 30. In the present embodiment, since the torque sensor 40 is provided on the dynamometer 20 side, as shown in FIG. 2B, the model is a three-mass inertial system in which the engine 10, the torque sensor 40, and the dynamometer 20 exist as masses. Be converted to In FIG. 2B, the original control target position and the measurement position where the load torque is actually detected are indicated by black circles. The control device 70 corrects the difference between the two positions using the model of the three-mass inertial system, and controls the dynamometer 20 so that the load torque generated from the dynamometer 20 becomes the target load torque at the original control target position. I do. Specifically, in the three-mass inertial system model, assuming that the equivalent inertia of the engine 10 is Jeg, the equivalent inertia of the torque sensor 40 is Jtm, and the equivalent inertia of the dynamometer 20 is Jdy, the gain of the engine 10 is Jeg / (Jeg + Jtm + Jdy). The gain of the torque sensor 40 is (Jeg + Jtm) / (Jeg + Jtm + Jdy), and the difference between the measurement position and the control target position is 20 log {(Jeg + Jtm) / Jeg} on the Bode diagram. The control device 70 corrects the load torque generated by the dynamometer 20 upward so as to eliminate the amplitude deviation. The control device 70 may control the dynamometer 20 by adding a predetermined offset in order to eliminate the above-mentioned deviation.
[0032]
FIG. 3 shows mechanical characteristics when a vibration is applied from the dynamometer 20 side in the three-mass inertial system model. For comparison, FIG. 4 shows mechanical characteristics when a two-mass inertial model is used. In both figures, (A) shows the frequency characteristics of the amplitude, and (B) shows the frequency characteristics of the phase. “DYside” is a mechanical characteristic on the dynamometer 20 side, and “EGside” is a mechanical characteristic on the engine 10 side. The amplitude = 0 dB indicates that 100% of the torque desired to be transmitted from the dynamometer 20 is transmitted to the engine 10.
[0033]
As shown in FIG. 4A, when the two-mass inertial system model is used despite the fact that the torque sensor 40 is provided on the dynamometer 20 side, it becomes 0 dB on the dynamometer 20 side and 0 dB on the engine 10 side. The amplitude will be lower. That is, it means that only load torque lower than the original target load torque is applied to the engine side 10. This is because the load torque detected by the torque sensor 40 is not the load torque on the engine 10 side but the load torque on the dynamometer 20 side. On the other hand, when the three-mass inertial system model is used as shown in FIG. 3A, the target load torque is calculated with respect to the load torque detected by the torque sensor 40 in consideration of the gain in the three-mass inertial system. Because of the upward correction (more correction), an amplitude of 0 dB can be obtained on the engine 10 side.
[0034]
As described above, in the present embodiment, by providing the torque sensor 40 on the dynamometer 20 side, various problems caused by providing the torque sensor 40 on the engine 10 side can be solved, and the load torque detected by the torque sensor 40 can be solved. Is different from the load torque on the crankshaft of the engine 10 which is the target of the original control, and a three-mass system in which the engine 10 and the torque sensor 40 are connected by the high rigidity and low inertia shaft 30 is also considered. By upwardly correcting the additional torque applied from the dynamometer 20 to the engine 10 using the inertial system, the target load torque can be reliably applied to the crankshaft of the engine 10 and the engine 10 can be tested.
[0035]
The control device 70 according to the present embodiment can be configured by a VME or a PC in addition to the DSP that executes the simulation program.
[0036]
In this embodiment, a carbon shaft is used as the shaft 30 connecting the engine 10 and the dynamometer 20, but any material can be used as long as it has high rigidity and low inertia.
[0037]
【The invention's effect】
As described above, according to the present invention, it is possible to suppress the occurrence of abnormality in the load torque detecting means, and to test the prime mover by applying a desired load torque to the prime mover with high accuracy.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a test apparatus according to an embodiment.
FIG. 2 is an explanatory diagram of a model of a three-mass inertial system.
FIG. 3 is a graph showing mechanical characteristics of a three-mass inertial system according to the embodiment.
FIG. 4 is a graph showing mechanical characteristics of a two-mass inertial system.
FIG. 5 is a configuration diagram of a conventional test apparatus.
FIG. 6 is a conceptual diagram of a vehicle dynamic characteristic model.
[Explanation of symbols]
10 engine, 20 dynamometer, 30 shaft, 40 torque sensor, 70 control device.

Claims (3)

Load torque applying means for applying load torque to the drive shaft of the vehicle prime mover via a coupling shaft connected to the drive shaft of the vehicle prime mover;
Load torque detecting means for detecting the magnitude of the load torque applied by the load torque applying means,
Calculating a desired load torque to be applied based on a dynamic characteristic model using model constants such as an equivalent inertia, an equivalent damping constant, and an equivalent spring constant of a drive system including a transmission connected to the prime mover; Control means for controlling the load torque application means based on a difference from the actual load torque detected by the detection means,
A motor testing device having
The load torque detecting means is provided between the coupling shaft and the load torque applying means,
An apparatus for testing a prime mover, wherein the control means controls the load torque applying means so that the desired load torque is applied to a drive shaft of the prime mover according to a position of the load torque detecting means. The device of claim 1,
The control means controls the load torque application means such that the desired load torque is applied to the drive shaft of the prime mover using the load torque detection means and model characteristics of the coupling shaft. Motor testing equipment. The device of claim 1,
The control means models a control system including the prime mover, the load torque detecting means and the load torque applying means, wherein the prime mover and the load torque detecting means are modeled as a three-mass inertial system elastically coupled by the coupling shaft. A test apparatus for a motor, wherein the load torque applying means is controlled so that the desired load torque is applied to a drive shaft of the motor.

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