Fault detection and mitigation in hybrid drive system

• US 10,030,648 B2
• Filed: 02/09/2015
• Issued: 07/24/2018
• Est. Priority Date: 06/11/2009
• Status: Active Grant

• Current Assignee: Danfoss Power Solutions II Technology A/S
• Original Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Inventors: Stoner, Michael Anthony, Hawkins, Thomas D., Simpson, Douglas D.
• Primary Examiner(s): Kirkland, III, Freddie
• Application Number:
  US14/617,431
• Publication Number:
  US 20150152861A1
• Time in Patent Office: 1,261 Days
• Field of Search: 7311201
• CPC Class Codes: B60K 6/12 by means of a chargeable fluidic accumulator
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: F02D 2041/1432 the system including a filter, e.g. a low pass or high pass filter
• CPC Class Codes: F02D 2041/224 Diagnosis of the fuel system
• CPC Class Codes: F02D 2041/225 Leakage detection
• CPC Class Codes: F02D 2041/227 Limping Home, i.e. taking specific engine control measures at abnormal conditions
• CPC Class Codes: F02D 29/02 peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F04B 49/103 Responsive to speed
• CPC Class Codes: F04B 51/00 Testing machines, pumps, or pumping installations
• CPC Class Codes: G01M 17/00 Testing of vehicles testing fluid tightness G01M3/00; testing elastic properties of bodies or chassis, e.g. torsion-testing, G01M5/00; testing alignment of vehicle headlight devices G01M11/06; testing of engines G01M15/00
• CPC Class Codes: G01M 3/00 Investigating fluid-tightness of structures
• CPC Class Codes: G01M 3/002 by using thermal means
• CPC Class Codes: G01M 3/26 by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

Fault detection and response systems and processes can be used for pumps, e.g., pump/motors used in hybrid vehicles. The fault detection systems determine when certain operating conditions, which may affect the proper operation of the system, occur. The response systems take appropriate action based on which fault conditions are triggered. Example fault detection systems and processes include detection systems for different types of leaks, sensor malfunctions, or operation errors.

Claims

1. A detection method for detecting a barrel leak in a pump system, the method comprising:

obtaining a data signal from a filter pressure sensor of the pump system, the filter pressure sensor indicating a pressure at a filter of the pump system;

obtaining a data signal from a pump speed sensor of the pump system;

determining a rotation frequency of a pump of the pump system based on the data signal from the pump speed sensor;

filtering the data signal received from the filter pressure sensor based on the rotation frequency of the pump to obtain a filtered signal; and

determining a predetermined threshold using pressure spike thresholds mapped for different operating conditions including different swash angle positions or different pressure readings; and

analyzing the filtered signal to determine whether the filtered signal exceeds the predetermined threshold.

2. The detection method of claim 1, wherein filtering the data signal comprises:

passing the data signal obtained from the filter pressure sensor through a high-pass filter to obtain a first filtered signal;

rectifying the first filtered signal to obtain a rectified signal; and

passing the rectified signal through a low-pass filter to obtain the filtered signal.

3. The detection method of claim 2, wherein the high-pass filter is a butterworth filter.

4. The detection method of claim 1, further comprising adjusting a swash plate of the pump system to a zeroed out position when the filtered signal exceeds the predetermined threshold.

5. The detection method of claim 1, further comprising alerting a user when the filtered signal exceeds the predetermined threshold.

6. The detection method of claim 1, further comprising opening a bypass between the pump in the pump system and a reservoir when the filtered signal exceeds the predetermined threshold.

7. The detection method of claim 1, wherein the pump system is part of a second power source of a hybrid drive assembly of a vehicle having a primary power source.

8. The detection method of claim 7, further comprising disengaging the second power source from the hybrid drive assembly when the filtered signal exceeds the predetermined threshold.