JP2006078392A - Fault detection method for resolver signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a fixed signal extending over the entire angle range, and to detect faults precisely, by obtaining the sum of squares of bi-phase resolver signals and setting it as a sum-of-squares signal. <P>SOLUTION: In a fault detection method of the resolver signals, by obtaining a sine signal (1) and a cosine signal (2) are converted into direct currents and squared and the sum, the sum of the squares of the output sin<SP>2</SP>+cos<SP>2</SP>is obtained. Since the level is constant over the entire angle range, faults can be detected with high accuracy by processing, using a window-type comparator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resolver signal abnormality detection method, and more particularly to a novel improvement for determining the presence or absence of an abnormality in a resolver signal using a square sum output obtained by summing squares of two-phase output signals.

Conventionally, as a method for detecting an abnormality of this type of resolver signal, a method shown in FIG. 2 has been adopted, although no patent document is disclosed.
That is, in FIG. 2, two-phase sin signal 1 and cos signal 2 output from a resolver (not shown) are converted into DC signals by the first and second AC / DC converters 3 and 4, respectively, and then added. 5 is added, and the added addition output sin + cos is input to the window type comparator 10.

In the window type comparator 10, the summed output sin + cos has a ripple shape of 1 to 1.4 times over the entire angle range, and therefore detection according to the level of the summed output sin + cos of 1 to 1.4 times the ripple shape. Window 11 is set.
Therefore, when a signal deviating from the detection window 11 is generated, the abnormal time 11b is detected with respect to the normal time 11a.

Since the conventional resolver signal abnormality detection method is configured as described above, the following problems exist.
That is, since the evaluation was based on the sum of the sin signal and the cos signal, it was necessary to determine that the range of 1 to 1.4 times the ripple was generated as normal, and it was impossible to accurately detect the abnormality. .

  According to the resolver signal abnormality detection method of the present invention, the sin signal and the cos signal output from the resolver are converted into direct current, then squared with each signal, added by an adder, and obtained from the adder. In this method, the square sum output is judged as normal / abnormal using a window type comparator.

Since the resolver signal abnormality detection method according to the present invention is configured as described above, the following effects can be obtained.
That is, since the two-phase resolver signal is converted to direct current and summed to the square, the output signal sin ² + cos ^2, that is, the sum of squares output, is constant over the entire angle range, so the detection window is made smaller than before. This makes it possible to make a very accurate abnormality determination.

  According to the present invention, the resolver signal is converted into direct current and summed with a square, so that a highly accurate abnormality determination can be performed by utilizing the fact that the sum of squares output is constant over the entire angle range.

A preferred embodiment of a resolver signal abnormality detection method according to the present invention will be described below with reference to the drawings.
The same reference numerals are used for the same or equivalent parts as in the conventional example.
In FIG. 1, a two-phase sin signal 1 and a cos signal 2 output from a resolver (not shown) are converted into DC signals by first and second AC / DC converters 3 and 4, respectively. The squares 20 and 21 are squared and then added by the adder 5 to obtain a square sum output sin ² + cos ² .

The square sum output sin ² + cos ² is input to the window-type comparator 10, and an abnormality determination is performed by the detection window 11 having a window in a smaller range than the conventional one.
In this case, the square sum output sin ² + cos ² is constant over the entire angle range, so that it is possible to determine abnormality over almost the entire range.

  In addition, since the resolver signal may be inaccurate due to a change in the level of one side of the sin signal 1 and the cos signal 2, this abnormality determination can also be used as an accuracy determination.

  The present invention is applicable not only to resolvers but also to synchros and the like.

It is a block diagram which shows the abnormality detection method of the resolver signal by this invention. It is a block diagram which shows the abnormality detection method of the conventional resolver signal.

Explanation of symbols

1 sin signal 2 cos signal 3 No. 1AC / DC converter 4 No. 2AC / DC converter 5 adder 10 window comparator 20 first square section 21 second square section ^sin 2 + cos ² square sum output

Claims (1)

After the sin signal (1) and the cos signal (2) output from the resolver are converted to direct current, the signals (1, 2) are squared and added by the adder (5), and the adder ( 5. A resolver signal abnormality detection method, wherein normal / abnormal determination is performed on a square sum output (sin ² + cos ² ) obtained from 5) using a window comparator.

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