Throttle control module

• US 8,408,181 B2
• Filed: 02/19/2010
• Issued: 04/02/2013
• Est. Priority Date: 02/20/2009
• Status: Active Grant

• Current Assignee: Johnson Electric International AG (Johnson Electric Holdings Limited)
• Original Assignee: Johnson Electric SA 125 Rue de Progres La Chaux de Fonds Switzerland (Johnson Electric Holdings Limited)
• Inventors: Li, Yong Bin, Qin, Rui Feng, Sun, Ning, Wen, Chao, Yeung, Yuk Wai Elton
• Primary Examiner(s): Kwon, John T.
• Assistant Examiner(s): HOANG, JOHNNY H
• Application Number:
  US12/708,971
• Publication Number:
  US 20100212628A1
• Time in Patent Office: 1,138 Days
• Field of Search: 123/339.14, 123/339.23, 123/339.26, 123/336, 123/337, 123/361, 123/367, 123/376, 123/403
• US Class Current: 123/339.14
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 2011/102 at least one throttle being moved only by an electric actuator
• CPC Class Codes: F02D 2041/2027 Control of the current by pulse width modulation or duty cycle control
• CPC Class Codes: F02D 2200/0404 Throttle position
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/20 Output circuits, e.g. for controlling currents in command coils
• CPC Class Codes: F16K 31/043 characterised by mechanical means between the motor and the valve, e.g. lost motion means reducing backlash, clutches, brakes or return means
• CPC Class Codes: F16K 31/046 with electric means, e.g. electric switches, to control the motor or to control a clutch between the valve and the motor F16K31/041 takes precedence
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A throttle control module for controlling a throttle, comprises: a BLDC motor; a gear train connecting the motor to the throttle; and a throttle position sensor. A PWM module is connected to the throttle position sensor and generates a pulse-width modulation sequence according to the signal from the throttle position sensor and a desired throttle position signal. A decoder module generates commutation logic for the motor based on the signal from the throttle position sensor. A motor controller controls commutation of the motor according to the pulse-width modulation sequence and the commutation logic.

Claims

1. A throttle control module for controlling a throttle, comprising:

a brushless direct current motor for moving the throttle, the brushless direct current motor having a permanent magnet rotor, the permanent magnet rotor having a number of pole pairs;

a gear train having a reduction coefficient and connecting the brushless direct current motor to the throttle;

a throttle position sensor generating a throttle position signal indicative of the position of the throttle;

a pulse-width modulation module connected to the throttle position sensor, generating a pulse-width modulation sequence according to the throttle position signal from the throttle position sensor and a desired throttle position signal;

a decoder module connected to the throttle position sensor, performing decoding calculation on the throttle position signal from the throttle position sensor to generate commutation logic for the brushless direct current motor; and

a motor controller connected to the pulse-width modulation module and the decoder module, to control commutation of the brushless direct current motor according to the pulse-width modulation sequence and the commutation logic;

wherein the decoder module comprises;

an analog-digital converter for converting the throttle position signal from the throttle position sensor into a digital throttle position signal and calibrating the digital throttle position signal; and

a decoding calculation unit for performing decoding calculation based on the calibrated digital throttle position signal, the conversion precision of the analog-digital converter, the number of pole pairs of the rotor and the reduction coefficient of the gear train to get an electrical angle corresponding to the current position of the throttle, and generating the commutation logic according to the electrical angle; and

wherein the decoder module calculates the electrical angle according to the equation;

2. The throttle control module of claim 1, wherein the gear train comprises:

a driving gear fixed on an output shaft of the brushless direct current motor;

a driven gear fixed on an input shaft of the throttle, the radius of the driven gear being larger than the radius of the driving gear; and

a transmission gear disposed between and in mesh with the driving gear and the driven gear.

3. The throttle control module of claim 2, wherein the transmission gear is a dual tier gear comprising a larger gear and a smaller gear coaxially disposed, the larger gear being in mesh with the driving gear and the smaller gear being in mesh with the driven gear.

4. The throttle control module according of claim 1, wherein the brushless direct current motor is a Hall sensor-less motor.

5. A method of controlling a throttle comprising the steps of:

providing a brushless direct current motor connected to the throttle by a reduction gear train, the brushless direct current motor having a permanent magnet rotor having a number of pole pairs;

receiving a throttle position signal from a throttle position sensor;

converting the throttle position signal into a digital throttle position signal;

calibrating the digital throttle position signal;

generating commutation logic for the brushless direct current motor by performing decoding calculation on the calibrated digital position signal;

generating a pulse-width modulation sequence according the calibrated digital position signal and a desired throttle position signal; and

controlling commutation of the brushless direct current motor according to the pulse-width modulation sequence and the commutation logic to control the throttle;

wherein the step of generating the commutation logic for the brushless direct current motor comprises;

generating an electrical angle corresponding to the current opening position of the throttle by means of performing decoding calculation on the calibrated digital throttle position signal, the number of precision bits of the analog-digital converter, and the number of pole pairs of the rotor; and

generating the commutation logic by means of performing decoding calculation on the electrical angle and;

wherein the electrical angle G is generated according to the equation;

6. The method of claim 5, further comprising the steps of providing the gear train with a driving gear fixed on an output shaft of the brushless direct current motor, a driven gear fixed on an input shaft of the throttle, and a dual tier transmission gear in mesh with the driving gear and the driven gear, the radius of the driven gear being larger than radius of the driving gear.