Voltage Injection-Based Cable Swap Detection

Patent metadata

Field	Value
Publication number	US-2016268944-A1
Application number	US-201514643195-A
Country	US
Kind code	A1
Filing date	Mar 10, 2015
Priority date	Mar 10, 2015
Publication date	Sep 15, 2016
Grant date	—

Abstract

A vehicle includes an electric machine and a controller configured to inject a voltage into the electric machine. The controller measures the currents caused by the voltage and processes the currents using a discrete Fourier transform to determine positive and negative sequence currents. A phase rotation sequence is identified by comparing the sequence currents to expected positive and negative sequence currents that are associated with possible phase rotation sequences. The electric machine may be controlled according to the identified phase rotation sequence. A cable swapped diagnostic may be output when the phase rotation sequence is different than an expected phase rotation sequence.

First claim

What is claimed is:

1 . A vehicle comprising:
a controller programmed to, in response to a power-on condition, inject a voltage having a predetermined phase rotation sequence into a three-phase electric machine and output a signal indicative of a phase rotation sequence based on a comparison of predetermined sequence current magnitudes and sequence current magnitudes associated with a current flowing through the three-phase electric machine.

2 . The vehicle of claim 1 wherein the controller is further programmed to, in response to the signal indicating that the phase rotation sequence is different than the predetermined phase rotation sequence, output a cable swapped diagnostic.

3 . The vehicle of claim 1 wherein the predetermined sequence current magnitudes are based on an inductance of the three-phase electric machine.

4 . The vehicle of claim 1 wherein the predetermined sequence current magnitudes are based on a magnitude of the voltage.

5 . The vehicle of claim 1 wherein the predetermined sequence current magnitudes are based on a frequency of the voltage.

6 . The vehicle of claim 1 wherein the sequence current magnitudes associated with the current are derived from a discrete Fourier transform of measurements of the current.

7 . The vehicle of claim 1 wherein the controller is further programmed to operate the three-phase electric machine according to the signal to cause the three-phase electric machine to rotate in a predetermined direction corresponding to the predetermined phase rotation sequence.

8 . The vehicle of claim 1 wherein the voltage has a predetermined frequency and a predetermined magnitude such that the three-phase electric machine does not rotate when the voltage is injected.

9 . The vehicle of claim 1 wherein the power-on condition includes a speed of the vehicle being approximately zero and a torque request to the three-phase electric machine being approximately zero.

10 . The vehicle of claim 1 wherein the predetermined sequence current magnitudes include sequence current magnitudes associated with the predetermined phase rotation sequence.

11 . A vehicle comprising:
an electric machine that rotates in a predetermined direction in response to application of a predetermined phase rotation sequence; and a controller programmed to inject a voltage with the predetermined phase rotation sequence into the electric machine and output a signal indicative of a phase rotation sequence based on a comparison of predetermined sequence current magnitudes and sequence current magnitudes associated with a current caused by a voltage.

12 . The vehicle of claim 11 wherein the controller is further programmed to, in response to the signal indicating that the phase rotation sequence is different than the predetermined phase rotation sequence, output a cable swapped diagnostic.

13 . The vehicle of claim 11 wherein the controller is further programmed to, in response to the signal indicating that the phase rotation sequence is different than the predetermined phase rotation sequence, disable operation of the electric machine.

14 . The vehicle of claim 11 wherein the controller is further programmed to operate the electric machine according to the signal indicative of the phase rotation sequence to cause the electric machine to rotate in a predetermined direction corresponding to the predetermined phase rotation sequence.

15 . The vehicle of claim 11 wherein the predetermined sequence current magnitudes are based on one or more of an inductance of the electric machine, a magnitude of the voltage, and a frequency of the voltage.

16 . A method comprising:
applying, by a controller, voltage to an electric machine based on an injection voltage reference; and operating, by the controller, the electric machine based on a phase rotation sequence derived from a comparison of predetermined sequence current magnitudes and sequence current magnitudes associated with a current caused by the voltage.

17 . The method of claim 16 wherein the predetermined sequence current magnitudes are based on parameters of the injection voltage reference and parameters of the electric machine.

18 . The method of claim 16 wherein the sequence current magnitudes are based on a discrete Fourier transform of measurements of the current.

19 . The method of claim 16 wherein a frequency of the injection voltage reference is a predetermined multiple of a switching frequency corresponding to a rate at which the voltage is changed.

20 . The method of claim 16 further comprising outputting, by the controller, a cable swapped diagnostic in response to the phase rotation sequence being different than an expected phase rotation sequence.

Assignees

• Ford Global Tech Llc

Inventors

• Xu Wei
• Syed Fazal Urrahman

Classifications

• H02P21/0035 Primary

  Electricity · mapped topic

• B60L15/20 Primary

  for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed · CPC title

• Y02T10/64

  Electric machine technologies in electromobility · CPC title

• Y02T10/7072

  Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors · CPC title

• B60R16/0232

  for measuring vehicle parameters and indicating critical, abnormal or dangerous conditions · CPC title