Detection Method of Current Sensor Faults in the E-Drive System By Using the Voltage Command Error

• US 20150061708A1
• Filed: 08/27/2013
• Published: 03/05/2015
• Est. Priority Date: 08/27/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Wang, Chang-jiang, Degner, Michael, Isayeva, Rimma, Xu, Liwen, Luedtke, Daniel R.
• Granted Patent: US 9,372,234 B2
• Time in Patent Office: Days
• US Class Current: 324/750.02
• CPC Class Codes: G01R 31/3191 Calibration
• CPC Class Codes: H02P 29/024 Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load
• CPC Class Codes: H02P 29/0241 the fault being an overvoltage

Abstract

Systems, apparatus, and methods detect a current sensor error in an FOC electric machine system. A voltage command is monitored to detect the presence of an ac component can indicate that an error has occurred at a current sensor. By way of example, a sensor fault detection module can be configured to determine the deviation between an actual voltage command and an ideal voltage command to provide a complex deviation vector. By transforming the deviation vector to a reference frame rotating at the fundamental frequency of the command voltage, a dc component of the positive and negative sequences can be filtered, and their amplitudes determined. Error detection can be based on the total amplitude of the fundamental component, determined by positive and negative component amplitudes. The invention enables an FOC system to operate with two current sensors, rather than three, and provides a dedicated fault diagnostic for a current sensor.

Claims