Active vibration control system for hybrid vehicle

• US 20070222407A1
• Filed: 03/09/2007
• Published: 09/27/2007
• Est. Priority Date: 03/23/2006
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Takahashi, Akira, Kobayashi, Yasunori, Inoue, Toshio, Sakamoto, Kosuke
• Granted Patent: US 7,633,257 B2
• Time in Patent Office: Days
• US Class Current: 318/611
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2050/0054 Cut-off filters, retarders, delaying means, dead zones, threshold values or cut-off frequency
• CPC Class Codes: B60W 30/20 Reducing vibrations in the driveline
• CPC Class Codes: G05D 19/02 characterised by the use of electric means

Abstract

In a motor-assisted hybrid vehicle, an active vibration control system suppresses torque fluctuations of an engine without detriment to the response of a static torque. An adaptive notch filter outputs a control signal depending on a harmonic basic signal generated by a basic signal generator from a rotational frequency of a crankshaft. A combiner combines the control signal with a drive signal for the generator motor and supplies the combined signal through a power controller to the generator motor. The basic signal is supplied to corrective filters having the transfer function of the generator motor to output a reference signal. The filter coefficient of an adaptive notch filter is successively updated so that an error signal representative of a rotational speed fluctuation of the crankshaft will be minimized.

Claims

1. An active vibration control system for use in a hybrid vehicle having a generator motor for assisting an engine in rotating a crankshaft thereof, comprising:

a basic signal generator for generating a harmonic basic signal from a rotational frequency of the crankshaft;

an adaptive notch filter for being supplied with said basic signal and outputting a control signal;

a combiner for combining said control signal and a drive signal for said generator motor with each other and supplying a combined signal to said generator motor;

an error signal detector for detecting a rotational speed fluctuation of the crankshaft and outputting an error signal representative of the detected rotational speed fluctuation;

a corrective filter for being supplied with said basic signal and outputting a reference signal, said corrective filter having a transfer function of said generator motor; and

filter coefficient updating means for being supplied with said error signal and said reference signal and successively updating a filter coefficient of said adaptive notch filter so that said error signal will be minimized.

2. A hybrid vehicle incorporating an active vibration control system according to claim 1.

3. A method of improving a vibration control capability of a hybrid vehicle having a generator motor for assisting an engine in rotating a crankshaft thereof, comprising the steps of:

generating a harmonic basic signal from a rotational frequency of the crankshaft with a basic signal generator;

multiplying a transfer function of said generator motor by said basic signal with a reference signal generating circuit to generate a reference signal;

detecting a rotational speed fluctuation of said crankshaft with an error signal detector to generate an error signal;

updating a filter coefficient of an adaptive notch filter so that said error signal will be minimized, based on said reference signal and said error signal, with filter coefficient updating means;

processing said basic signal with said adaptive notch filter to generate a control signal; and

combining said control signal and a drive signal for said generator motor with each other and supplying a combined signal to said generator motor;

whereby vibrations of said crankshaft is reduced to increase a vibration control capability of said hybrid vehicle.