JP3517920B2 - Throttle valve opening control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle valve opening control device for an engine in an engine dynamometer or chassis dynamometer. 2. Description of the Related Art FIG. 4 shows an example of the configuration of a dynamometer for engine testing. A dynamometer 3 having a motor configuration is directly connected to an output shaft of the engine 1 via a connecting shaft 2, and the output torque of the engine 1 is absorbed by the dynamometer 3. This torque control is performed by the torque controller 4. [0003] Speed controller 5 compares the detected value of the speed setpoint N _S and the speed detector 6, to obtain an opening degree control signal theta * of the throttle valve 1A of the engine 1. Using the opening control signal θ * as an opening command, the throttle controller 7 controls the opening of the throttle valve 1A via the throttle actuator 8. The operation mechanism of the throttle valve 1A is shown in FIG.
Shown in The lever 12 for changing the opening θ of the blade 10 of the throttle valve 1A is connected to a take-up drum 16 via a wire 14 and a guide tube 15 in addition to an operation valve 13 (or a wire directly connected to the accelerator) attached to the engine. The opening degree θ can be adjusted by the rotation of the drum 16. [0005] The winding drum 16 is axially connected to a motor 17 and obtains rotation according to the rotation amount of the motor 17. In addition to this electric mechanism, there is also a hydraulic actuator that performs stroke control by hydraulic pressure. Here, there are the following two methods for controlling the throttle valve. (1) Throttle opening control by detecting the position of the throttle actuator A potentiometer 18 for detecting the position is provided on the winding drum 16 of the throttle actuator or the like, and the detection signal of the potentiometer 18 is used as a feedback signal to determine the rotation amount of the motor 17, etc. Adjust the output position of the actuator. (2) Throttle opening control by detecting throttle valve opening A position detector 19 such as a rotary encoder is directly connected to the axis of the blade 10 of the throttle valve 1A, and the opening θ is directly detected. Is used as a feedback signal to adjust the output position of the actuator such as the amount of rotation of the motor 17. In the conventional control method (1), since the position of the actuator alone is controlled, the actuator is subject to disturbances such as a change in the length of the wire 14 and vibrations, particularly, backlash. It is difficult to maintain the positional relationship between the throttle valve and the throttle valve linearly in a one-to-one relationship, so that the actual opening of the throttle valve and the command become non-linear, and the actual opening of the throttle valve may not be accurately matched. In this respect, in the control method (2), high accuracy can be obtained because the opening of the throttle valve is directly detected, and the control method is also used for evaluation of an engine control unit. However, in the control method (2), the rigidity of the mounting shaft connecting the throttle valve and the encoder is low, and the shaft is twisted. The response of the valve control system is designed to be, for example, 0.1 seconds (0-90 degree operation). However, when trying to obtain high response, vibration is caused by the presence of the shaft torsion, and as a result, the response is improved. It may not be possible. Therefore, the conventional control system has a disturbance caused by the backlash 24 and the torsion 25 of the encoder mounting shaft as shown in FIG.
In the figure, PI controller 21 and ASR (speed control system)
Reference numeral 22 corresponds to the throttle controller 7, and 1 / S (speed-opening position conversion) 23 corresponds to an operation mechanism including the throttle actuator 8. The backlash 24 largely depends on a wire or the like for obtaining the connection between the operating mechanism and the throttle valve, and the control method (1) cannot increase the accuracy. Further, the torsion 25 of the mounting shaft of the encoder is largely due to the low rigidity of the coupling shaft between the throttle valve and the encoder, and the responsiveness cannot be improved by the control method (2). SUMMARY OF THE INVENTION It is an object of the present invention to provide a throttle valve opening control apparatus which eliminates the effects of backlash of an operating mechanism and torsional vibration of a position detector, thereby improving accuracy and responsiveness. In order to solve the above-mentioned problems, the present invention provides a throttle controller for obtaining an opening control signal in accordance with a throttle valve opening command of an engine, and a throttle controller in accordance with the opening control signal. A throttle valve opening control device for a dynamometer having an actuator for controlling the opening of a throttle valve, wherein the first opening detector detects the opening of the throttle valve from the operating position of the operating mechanism of the actuator. A second opening detector coupled to the throttle valve shaft for detecting a throttle valve opening; and the throttle controller comprises:
Preset the relationship between the actual opening degree of the throttle valve to the throttle valve opening command as a function characteristic, this function
The backlash of the operating mechanism is compensated as a numerical characteristic.
When the throttle valve opening command increases and decreases to compensate
A function generating unit having a hysteresis characteristic different from time to time, and a proportional / integral operation having a large time constant with a large deviation as a feedback signal using a detection value of the second opening detector with respect to the throttle valve opening command. Controller, the sum of the output of the function generator and the output of the controller with respect to the throttle valve opening command is set as the opening command, the detected value of the first opening detector is used as a feedback signal, and the deviation is calculated. An opening control amplifier for performing a proportional / integral operation with a small time constant is provided. The throttle controller performs a highly responsive opening control by obtaining a command from the opening control amplifier mainly in accordance with the function characteristics of the function generating section during the transition of the opening command,
In addition, the backlash of the operating mechanism is compensated by the function characteristics. In addition, when the opening command is in a steady state, a high-precision opening control is performed by obtaining a command of the opening control amplifier in accordance with a value obtained by adding the output of the controller to the output of the function generating section. Eliminates vibration caused by twisting the shaft. FIG. 1 is an equivalent block diagram showing an embodiment of the present invention. The throttle actuator 31 detects the rotation speed of the motor 17 by the pulse pickup 32, and uses the detected speed N _det as a feedback signal.
The speed is controlled by an actuator speed control system 33 and an actuator current control system 34 to control the opening of the throttle valve 1A. The motor 17 of the throttle actuator 31
Is connected to a potentiometer 18, and the rotational position of the motor is detected as the opening degree θ _det of the throttle valve 1A. The rotary encoder 19 coupled to the shaft of the throttle valve 1A generates a pulse having a cycle corresponding to the opening of the throttle valve 1A. This pulse signal is extracted by the pulse / position converter 35 as an opening detection signal θ _vdet . The above configuration is equivalent to a conventional actuator control system and detection system. In this embodiment, a different part from the conventional one is a throttle controller 36. The throttle controller 36 receives the throttle valve opening control signal θ * from the speed controller 5 and the throttle valve detection opening signal θ
Controller 36 for calculating the deviation of _Vdet in proportion and integration
_1, a function generator 36 ₂ for obtaining the actual opening control signal to the opening control signal theta * a real opening theta and opening control signal theta _V * of a function characteristic of the throttle valve 1A, controller 36 ₁ opening control amplifier 36 to obtain a speed command value obtained by adding the outputs of the ratio changing unit 36 ₂ and the actual opening control signal ₃
And The controller 36 _1, the opening detection value theta _vdet pulse / position transducer 35 detects the feedback signal. Further, the opening control amplifier 36 _3, the opening detection value theta _det potentiometer 18 detects a feedback signal. The function generator 36 ₂ has a function characteristics measured in advance by using a throttle valve operating mechanism as data. [0024] This measurement gives a trapezoid pattern with rising and part of the descent, as shown in FIG. 2 (a) with respect to opening control amplifier ₃₆₃ as opening command, as shown in (b) to determine the actual opening of the throttle valve 1A at that time from the rotary encoder 19, with the relationship between the opening command theta _v and the actual opening theta as shown in FIG. (c) as a graph the pattern data. This graph pattern data has different hysteresis characteristics when the opening command is increased and when the opening command is decreased, and has characteristics that compensate for the backlash of the operating mechanism. An error due to shaft vibration in the encoder 19 is excluded. The controller 36 _1, by increasing the proportional gain is set to proportional-integral operation of slow response by increasing the integration time constant. Opening control amplifier ₃₆₃ is to increase the proportional constant, is the proportional-integral operation with high response by reducing the integration time constant. The operation of this embodiment will be described below with reference to FIG. As shown in FIG. 3, as a command from the speed controller 5 to the throttle controller 36, in the throttle valve opening control for giving a trapezoidal pattern having a high rate of change to the opening command θ _v * until time t _1. of during a transient by slow response of the controller 36 _1, the opening control of the opening degree control amplifier ₃₆₃ in accordance with only the output of the function generator 36 ₂ is made. The control at this time is a quick response, and the backlash of the operating mechanism is reduced by the function generator 36 _2.
Is compensated by the function characteristic of Further, the vibration due to the torsion of the rotary encoder 19 does not affect the control system as a disturbance. Next, the time t _{1 at} which the fixed position opening control period is set.
In ~t _2, will opening control plus a control amount by the controller 36 ₁ of the control system, command and control that compensates for the error of the actual opening, that is, control with higher accuracy. At this time, the vibration due to the torsion of the rotary encoder 19 is
It is suppressed by the slow response of the controller 19. At the time of transition from time t _{2 to} time t ₃ , time t ₁
As in the case of up, the high responsiveness of the opening control by opening control amplifier ₃₆₃ in accordance only with the output of the function generator 36 _2. In the embodiment, the case of a dynamometer for an engine test is shown, but the same effect can be obtained by applying the present invention to a test of a chassis dynamometer or the like. As described above, according to the present invention, the function of the throttle controller is to set the relationship between the throttle valve opening command and the actual opening of the throttle valve as a function characteristic in advance. A controller that corrects the opening based on the detection value of the opening detector coupled to the throttle valve shaft and the throttle valve opening command, and the sum of the output of the function generator and the output of the controller as the opening command. An opening control amplifier for controlling the opening based on the opening detection signal of the operating mechanism is provided. (1) The opening control with high responsiveness is obtained at the time of the opening command transition, and the backlash of the operating mechanism is characterized by a function characteristic. Can be compensated for. (2) When the opening command is steady, high-precision opening control can be obtained by the output of the controller, and vibration caused by torsion of the shaft of the rotary encoder or the like can be eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing one embodiment of the present invention. FIG. 2 is a waveform chart showing characteristics measured by a function generator in the embodiment. FIG. 3 is a control waveform diagram of the embodiment. FIG. 4 is a configuration diagram of an engine test apparatus. FIG. 5 is an operation mechanism diagram of a throttle valve. FIG. 6 is a block diagram of a conventional control system. [Description of Signs] 1 ... Engine 1A ... Throttle valve 5 ... Speed controller 7 ... Throttle controller 8 ... Actuator 17 ... Motor 18 ... Potentiometer 19 ... Rotary encoder 31 ... Throttle actuator 33 ... Speed control system 34 ... Current control system 36 ... Throttle Controller 36 ₁ … Controller 36 ₂ … Function generator 36 ₃ … Opening control amplifier

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-219331 (JP, A) JP-A-61-261635 (JP, A) JP-A-55-17629 (JP, A) JP-A-63 193752 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 41/00-41/40 F02D 9/00-9/02 F02D 43/00-45/00

Claims (1)

(1) A throttle controller that obtains an opening control signal in accordance with an engine throttle valve opening command, and an actuator that controls the throttle valve opening in accordance with the opening control signal. A throttle valve opening control device for a dynamometer, comprising: a first opening detector that detects an opening of the throttle valve from an operation position of an operation mechanism of the actuator; and a first opening detector that is coupled to a shaft of the throttle valve. A second opening detector for detecting a throttle valve opening; and the throttle controller, wherein a relationship between a throttle valve opening command and an actual opening of the throttle valve is set in advance as a function characteristic.
The backlash of the operating mechanism is compensated as a numerical characteristic.
When the throttle valve opening command increases and decreases to compensate
A function generator having a history characteristic different from time to time, and a proportional / integral operation having a large time constant with a large deviation as a feedback signal using a detection value of the second opening detector with respect to the throttle valve opening command. And a controller that adds the output of the function generator to the throttle valve opening command and the output of the controller as an opening command, and uses the detection value of the first opening detector as a feedback signal to calculate the deviation. An opening control amplifier for a throttle valve, comprising an opening control amplifier for performing a proportional / integral operation with a small time constant.