Method and circuit for detecting a short circuit of the sine or cosine receiver coil of a resolver

Patent metadata

Field	Value
Publication number	US-10495494-B2
Application number	US-201615736042-A
Country	US
Kind code	B2
Filing date	Jun 7, 2016
Priority date	Jun 18, 2015
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

A method for detecting a short circuit to ground or to the operating voltage of a signal line ( 11, 12 ) of a resolver ( 16 ) has the following steps: —measuring the potential of the signal lines ( 13 a, 13 b; 14 a, 14 b ) of the receiver coil ( 18 ) with respect to ground at two sampling times (R and F) provided symmetrically at the middle of the excitation period; —calculating an offset value for a signal line pair ( 13 a, 13 b; 14 a, 14 b ) by calculating the average value of the four measured values (U HR , U LR , U HF and U LF ) for the associated receiver coil ( 17, 18 ); and —identifying a short circuit and the potential to which the short-circuited line is connected in that the offset value is compared to threshold values.

First claim

The invention claimed is:

1. A method for detecting a short circuit ( 10 ) to ground or to the operating voltage (UB) of a signal line ( 11 , 12 ) of a resolver ( 16 ), having the following steps:
measuring ( 31 ) the potential of the signal lines ( 13 a , 13 b ; 14 a , 14 b ) of the receiver coil with respect to ground at two sampling instants (R, F) which are situated symmetrically with respect to the midpoint of the excitation period; calculating ( 32 ) an offset value (UDC) for the respective signal line pair ( 13 a , 13 b ; 14 a , 14 b ) by forming the average of the four measured values (UHR, ULR, UHF, ULF) of the respective receiver coil ( 17 , 18 ); and
identifying ( 33 ) a short circuit and the potential toward which the short-circuited line is able to be pulled, by comparing the offset value to limit values.

2. The method as claimed in claim 1 , wherein pull-up resistors (R 1 ; R 3 ) and pull-down resistors (R 2 ; R 4 ) which are connected to the signal lines ( 13 a , 13 b ; 14 a , 14 b ) are supplied with a voltage potential via their other end.

3. The method as claimed in claim 2 , wherein the voltage potentials of the pull-up resistors (R 1 ; R 3 ) and the pull-down resistors (R 2 ; R 4 ) differ from one another by a constant amount which is smaller than the measurement range of the A/D converters for the measured values of the receiver coil.

4. A circuit for detecting a short circuit of a signal line ( 11 , 12 ) of a resolver ( 16 ) to ground or to the operating voltage (UB), including:
a control device ( 1 ) including a processor ( 2 ), power stages ( 3 , 4 ) and first terminals ( 6 , 7 ) for providing signals for excitation lines ( 11 , 12 ) to an excitation coil ( 16 ) of the resolver ( 15 ), and second terminals ( 7 a , 7 b , 8 a , 8 b ) for connecting signal lines ( 13 a , 13 b , 14 a , 14 b ) for the signals of a sine coil and a cosine coil ( 17 , 18 );
two A/D converters ( 21 , 22 ) which are connected to the second terminals ( 7 a , 7 b and 8 a , 8 b ) of the control device ( 1 ), the outputs of which being readable and evaluable by the software of the processor ( 2 );
the excitation lines ( 11 , 12 ) which couple the first terminals ( 5 , 6 ) of the excitation coil ( 16 ) to the resolver ( 15 );
the signal lines ( 13 a , 13 b , 14 a , 14 b ) which are to be diagnosed for the sine and cosine signals provided by the resolver ( 15 ), and which couple the resolver to the two terminals ( 7 a , 7 b , 8 a , 8 b ) of the control device ( 1 );
pull-up resistors (R 1 , R 3 ) which are connected via their one end to one of the terminals ( 7 a , 8 a ) for the conductors ( 13 a , 14 a ) sine coil ( 17 ) and of the cosine coil ( 18 ), and via their other end to a first DC voltage potential (UH);
pull-down resistors (R 2 and R 4 ) which are connected via their one end to the other one of the terminals ( 7 b , 8 b ) for the lines ( 13 b , 14 b ) sine coil ( 17 ) and of the cosine coil ( 18 ), and which are connected via their other end to a second DC voltage potential (UL);
four electronic switches ( 26 , 27 , 28 , 29 ) which are inserted into the connection of the terminals ( 7 a , 7 b ; 8 a , 8 b ) for the signal lines ( 13 a , 13 b ; 14 a , 14 b ) to inputs (H, L) of the A/D converters ( 21 , 22 ), wherein the switches ( 26 , 27 , 28 , 29 ) are configured such that they respectively disconnect one input of the A/D converter ( 21 , 22 ) from the signal line ( 13 a , 13 b ; 14 a , 14 b ) and temporarily connect this input to ground;
and
a display and/or storage device ( 9 ) for displaying and/or storing the information identified by the processor ( 2 ), into which the positive detection of a short circuit ( 10 ) of a signal line ( 11 , 12 ) of a resolver ( 16 ) to ground or to the operating voltage (UB) by the processor ( 2 ) is incorporated.

5. The circuit as claimed in claim 4 , wherein the pull-up resistors (R 1 and R 3 ) and pull-down resistors (R 2 and R 4 ) are integrated into the control device ( 1 ).

6. The circuit as claimed in claim 4 or 5 , wherein the resistance values of the pull-up resistors (R 1 and R 3 ) and pull-down resistors (R 2 and R 4 ) are large relative to the ohmic resistance of the sine coil ( 17 ) and the cosine coil ( 18 ).

7. A circuit for detecting a short circuit of a signal line ( 11 , 12 ) of a resolver ( 16 ) to ground or to the operating voltage (UB), including:
a control device ( 1 ) including a processor ( 2 ), power stages ( 3 , 4 ) and first terminals ( 6 , 7 ) for providing signals for excitation lines ( 11 , 12 ) to an excitation coil ( 16 ) of the resolver ( 15 ), and second terminals ( 7 a , 7 b , 8 a , 8 b ) for connecting signal lines ( 13 a , 13 b , 14 a , 14 b ) for the signals of a sine coil and a cosine coil ( 17 , 18 );
two A/D converters ( 21 , 22 ) which are connected to the second terminals ( 7 a , 7 b and 8 a , 8 b ) of the control device ( 1 ), the outputs of which being readable and evaluable by the software of the processor ( 2 );
the excitation lines ( 11 , 12 ) which couple the first terminals ( 5 , 6 ) of the excitation coil ( 16 ) to the resolver ( 15 );
the signal lines ( 13 a , 13 b , 14 a , 14 b ) which are to be diagnosed for the sine and cosine signals provided by the resolver ( 15 ), and which couple the resolver to the two terminals ( 7 a , 7 b , 8 a , 8 b ) of the control device ( 1 );
pull-up resistors (R 1 , R 3 ) which are connected via their one end to one of the terminals ( 7 a , 8 a ) for the conductors ( 13 a , 14 a ) sine coil ( 17 ) and of the cosine coil ( 18 ), and via their other end to a first DC voltage potential (UH);
pull-down resistors (R 2 and R 4 ) which are connected via their one end to the other one of the terminals ( 7 b , 8 b ) for the lines ( 13 b , 14 b ) sine coil ( 17 ) and of the cosine coil ( 18 ), and which are connected via their other end to a second DC voltage potential (UL);
four additional A/D converters in which one input is set to ground, and the other inputs are connected to one of the terminals ( 7 a , 7 b , 8 a , 8 b ) for the signal lines ( 13 a , 13 b , 14 a , 14 b ) of the sine coil ( 17 ) and the cosine coil ( 18 );
and
a display and/or storage device ( 9 ) for displaying and/or storing the information identified by the processor ( 2 ), into which the positive detection of a short circuit ( 10 ) of a signal line ( 11 , 12 ) of a resolver ( 16 ) to ground or to the operating voltage (UB) by the processor ( 2 ) is incorporated.

8. The circuit as claimed in claim 7 , wherein the pull-up resistors (R 1 and R 3 ) and pull-down resistors (R 2 and R 4 ) are integrated into the control device ( 1 ).

9. The circuit as claimed in claim 7 , wherein the resistance values of the pull-up resistors (R 1 and R 3 ) and pull-down resistors (R 2 and R 4 ) are large relative to the ohmic resistance of the sine coil ( 17 ) and the cosine coil ( 18 ).

Assignees

• Bosch Gmbh Robert

Inventors

• Lechner Benjamin
• Zirkel Daniel
• Raichle Daniel
• Ungermann Michael

Classifications

• G01B7/30

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• G01D18/00 Primary

  Testing or calibrating apparatus or arrangements provided for in groups G01D1/00 - G01D15/00 · CPC title

• G01D5/2291

  Linear or rotary variable differential transformers (LVDTs/RVDTs) having a single primary coil and two secondary coils · CPC title

• G01R31/2829

  Testing of circuits in sensor or actuator systems (testing of apparatus for measuring electric or magnetic variables G01R35/00; testing of indicating or recording apparatus G01D; in airbag systems B60R21/0173; checking gas analysers G01N33/007; monitoring or fail-safe circuits for electromagnets H01F7/1844) · CPC title

• G01R31/025

  Physics · mapped topic