JP2005204388A - Apparatus and method for generating rotating angle detecting timing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for generating rotating angle detecting timing which can be realized with a low cost without using a large size component such as a capacitor. <P>SOLUTION: The apparatus for generating the rotating angle detecting timing includes a resolver for generating two types of sinusoidal wave signal voltages which have a predetermined phase difference from each other according to the rotating angle of a rotor, an exciting signal supply means for supplying an exciting signal for generating the two types of the sinusoidal wave signal voltages to the resolver, a detecting means for detecting the specific phase timing of the sine wave of the exciting signal, a period measuring means for measuring the period of the exciting signal, an arithmetic means for obtaining the period of time until the value of the exciting signal from the specific phase timing of the sine wave of the exciting signal becomes the maximum from the value of the measured period of the exciting signal, and a timing generating means for setting the timing for measuring the values of the two types of the sinusoidal wave signal voltages when the lapse time from the specific phase timing of the sine wave of the exciting signal coincides with the calculated period of time. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotation angle detection timing generation device and a rotation angle detection timing generation method for generating a timing for detecting a rotation angle of a rotating body.

  For example, in a rotating body such as a brushless motor, the rotational position (rotation angle) of the rotor is detected by a detector such as a resolver in order to generate a rotating magnetic field corresponding to the electrical angle, and a three-phase bridge is detected based on this detection signal. A method in which the control unit drives is adopted. The control unit also detects the rotational direction of the rotating body using these detectors.

  The resolver is a kind of rotary transformer, and includes two stator windings and one rotor winding. The two stator windings are mechanically arranged at a 90 degree angle. The amplitude of the signal obtained by magnetic coupling with the stator winding is a function of the position of the rotor (shaft) and the relative position of the stator. For this reason, from the resolver, two types of output signals modulated with a sin component (sine wave) and a cos component (cosine wave) of the shaft angle are obtained based on the input excitation signal.

  When detecting the position of the rotating body, the output signals of the sin component and the cos component are detected at the time when the voltage value of the excitation signal becomes maximum (that is, when sin ωt = 1 in FIG. 5A). It is known. (See Patent Document 1). As a method of detecting the time when the voltage value of the excitation signal becomes maximum, a method of differentiating the voltage value of the excitation signal and determining whether the voltage value of the excitation signal has become maximum based on this differential value. Is generally known.

JP 2003-235285 A

  In the above-described method of differentiating the voltage and detecting the time when sin ωt = 1, a capacitor having a large capacity, that is, a large physique is required. As described above, since the size of the capacitor becomes large, there is a drawback that the capacitor cannot be built in an IC or the like. Therefore, the circuit scale becomes large, and the size of the board on which the circuit is mounted and the housing that houses the board are increased. As a result, the cost increases. In addition, there is a concern that even a minute electric noise may cause a malfunction, and a stable output cannot be obtained.

  In view of the above problems, an object of the present invention is to provide a rotation angle detection timing generation device and a rotation angle detection timing generation method that can be realized at low cost without using large components such as capacitors.

Means for Solving the Problems and Effects of the Invention

The present invention provides a rotation angle detection timing generation device for solving the above-described problems. That is, according to claim 1,
An excitation signal supply that supplies two types of sine wave signal voltages having a predetermined phase difference to each other according to the rotation angle of the rotating body and an excitation signal for generating two types of sine wave signal voltages to the resolver. Means, detection means for detecting when the excitation signal at a specific phase timing (phase angle “ωt = 0”) of the excitation signal (sine wave) rises from the average voltage, and period measurement means for measuring the period of the excitation signal From the measured excitation signal cycle value, the calculation means to obtain the time from when the excitation signal rises from the average voltage until the excitation signal value becomes maximum, and from when the excitation signal rises from the average voltage And a timing generation means for setting a timing for measuring the values of two kinds of sinusoidal signal voltages when the elapsed time of the time coincides with the calculated time. A detection timing generator.

  In the above configuration, the timing for measuring the values of the two types of sine wave signal voltages is generated by calculation based on the period of the excitation signal. For this reason, it is only necessary to detect even when the value of the excitation signal rises from the average voltage. Therefore, there is no need to differentiate the waveform over the entire excitation signal as in the prior art. A circuit or calculation program for that purpose is unnecessary, and the cost can be reduced accordingly.

  According to the second aspect, the detection means, the period measurement means, the calculation means, and the timing generation means in the rotation angle detection timing generation apparatus of the present invention can be configured by a digital logic circuit.

  For example, a detection circuit (detection means) that detects when the value of the excitation signal rises from the average voltage, and a period measurement circuit (cycle) that measures the period of the excitation signal based on when the value of the excitation signal rises from the average voltage Measuring means), an arithmetic circuit (calculating means) for calculating the time from when the excitation signal value rises from the average voltage to the maximum excitation signal value from the measured excitation signal cycle value, and excitation Timing generation circuit (timing generation means) that uses a timing for measuring the values of two types of sinusoidal signal voltages when the elapsed time from when the signal value rises from the average voltage coincides with the calculated time The configuration can be taken.

  The digital logic circuit is constituted by an IC and does not require a large component such as a capacitor. With the above structure, the board on which the digital logic circuit is mounted and the housing for housing the board can be reduced in size, and the manufacturing cost can be reduced.

  According to claim 3, the timing generation circuit in the rotation angle detection timing generation device of the present invention has a delay period from when the value of the excitation signal is detected to rise from the average voltage to when the period of the excitation signal is cleared. It can be configured to include a delay period generation circuit for generating, generating timing during the delay period, and clearing the value of the period of the excitation signal after the end of the delay period. With this configuration, the measured excitation signal cycle can be reliably used for timing generation, and the waveform cycle of the next excitation signal can also be measured.

  According to claim 4, the rotation angle detection timing generation device of the present invention is applied to a control device for an electric power steering device including an electric motor for assisting a driver's steering operation, and the rotation angle of the electric motor is determined. Can be used to detect. A resolver is widely used as means for detecting the rotation angle of an electric motor. With this configuration, the rotation angle of the electric motor can be detected at an appropriate time, so that the control accuracy of the electric power steering control device is improved.

  According to claim 5, the rotation angle detection timing generation method of the present invention is a first step of inputting to a resolver that generates two types of output signals having a predetermined phase difference from each other according to the rotation angle of the rotating body. And a second step of measuring the period of the excitation signal, which is a sine wave for generating two types of output signals, and from the period until the excitation signal becomes maximum based on a predetermined phase timing of the excitation signal And a fourth step of generating a timing for measuring two types of output signals when a time calculated from a predetermined phase timing of the excitation signal has elapsed. It is characterized by that.

  With the above configuration, it is not necessary to differentiate the waveform of the excitation signal over the entire excitation signal as in the prior art. A circuit or calculation program for that purpose is unnecessary, and the cost can be reduced accordingly.

  According to the sixth aspect of the present invention, the generation of the timing in the fourth step of the rotation angle detection timing generation method of the present invention clears the period of the excitation signal after detecting when the value of the excitation signal rises from the average voltage. This is performed during the delay period until the excitation signal period is cleared after the delay period ends. With this configuration, the measured excitation signal cycle can be reliably used for timing generation, and the waveform cycle of the next excitation signal can also be measured.

  According to claim 7, the rotation angle detection timing generation method of the present invention is applied to a control device for an electric power steering apparatus including an electric motor for assisting a driver's steering operation, and the rotation angle of the electric motor is determined. Can be used to detect. A resolver is widely used as means for detecting the rotation angle of an electric motor. With this configuration, the rotation angle of the electric motor can be detected at an appropriate time, so that the control accuracy of the electric power steering control device is improved.

  According to claim 8, the predetermined phase timing of the excitation signal in the rotation angle detection timing generation device and rotation angle detection timing generation method of the present invention is the configuration when the waveform of the excitation signal (sine wave) rises from zero. Can be taken. In general, a method for detecting when the signal waveform rises from zero can be realized relatively easily by a known integrated circuit such as an operational amplifier. Further, since the sine wave takes both positive and negative values, it can be determined that the waveform has risen from zero at the timing when the negative value changes to a positive value (zero cross). This method of detecting the zero-cross timing can be realized with the simplest circuit configuration as compared with the method of detecting other values of the sine wave. Therefore, the number of parts constituting the circuit is minimized, and the cost is not increased.

  Incidentally, as described above, when the position of the rotating body is detected by the resolver, the sine component at the time when the voltage value of the excitation signal becomes maximum (that is, when sin ωt = 1 in FIG. 5A). And the output signal of the cos component needs to be detected. It is known that the time when sin ωt = 1 is a ¼ hour timing of the cycle with reference to the time when the excitation signal of the resolver which is a sine wave rises from the average voltage. Therefore, if the rotation angle detection timing is when the elapsed time from when the value of the excitation signal rises from the average voltage coincides with ¼ of the period value of the excitation signal, the most appropriate rotation angle detection timing A generation device and a rotation angle detection timing generation method can be configured.

  The rotation angle detection timing generation device and the rotation angle detection timing generation method that can be realized at low cost without using large parts such as capacitors, the time elapsed from when the value of the excitation signal rises from the average voltage is the period of the excitation signal. This is realized by setting the rotation angle detection timing to coincide with the time of 1/4 of the value of.

  Hereinafter, a rotation angle detection timing generation device and a rotation angle detection timing generation method of the present invention will be described with reference to the drawings. FIG. 1 is a block circuit diagram in which a rotation angle detection timing generation device based on a rotation angle detection timing generation method of the present invention is applied to a control device for a three-phase brushless DC motor. Note that the application range of the rotation angle detection timing generation device and the rotation angle detection timing generation method of the present invention is not limited to the control device for a three-phase brushless DC motor.

  1 is a three-phase brushless DC motor (hereinafter also simply referred to as a motor), 2 is a control circuit for performing drive control of the motor 1, 3 is a drive circuit including a three-phase inverter device for driving the motor 1, 4 and 5 are current sensors, 6 is a resolver, and 8 is a smoothing capacitor.

  The drive circuit 3 forms a three-phase AC voltage based on the three-phase gate control signal voltage for driving the three-phase inverter circuit input from the control circuit 2 and applies it to the motor 1. Since the circuit configuration and operation itself of the three-phase inverter circuit 3 are normal and well known, detailed description thereof is omitted.

  The resolver 6 is wound around a rotor fixed to the rotation shaft of the motor 1 and applied with a sinusoidal excitation voltage Vsinωt, and is wound around the stator with an electrical angle θ = π / 2 (90 °) away from each other. The output windings output a SIN output signal voltage and a COS output signal voltage as a pair of output voltages. Therefore, the SIN output signal voltage is Vm × sin ωt × sin θ, and the COS output signal voltage is Vm × sin ωt × cos θ. Hereinafter, when the maximum amplitude value Vm is assumed to be 1, the SIN output signal voltage is referred to as a SIN output signal (sin ωt × sin θ), and the COS output signal voltage is referred to as a COS output signal (sin ωt × cos θ). Similarly, in the sine wave excitation voltage V × sin ωt, assuming that the maximum value V of the amplitude is 1, the sine wave excitation voltage V × sin ωt becomes sin ωt, which is called an excitation signal.

  As shown in FIG. 1, a reference signal such as a pulse signal from the control circuit 2 is input to the excitation signal, and a waveform having a predetermined amplitude is generated by the excitation signal generation circuit 7 (excitation signal supply means of the present invention) based on the reference signal. It is supplied to the resolver 6. The excitation signal generation circuit 7 may be built in the control circuit 2.

  The control circuit 2 includes a known microcomputer and its peripheral circuits, and forms another one-phase current from the two-phase currents input from the current sensors 4 and 5, and these three-phase currents and the rotation angle signal from the resolver 6. In addition, the magnitude and timing of a total of six three-phase gate voltage signals to be output to the three-phase inverter circuit 3 based on an external command are determined and output to the three-phase inverter circuit 3 to drive the three-phase brushless DC motor 1 Control. This type of three-phase brushless DC motor drive control itself, including various variations, is already well known and is not the gist of the present invention, and therefore detailed description thereof is omitted. The control circuit 2 may be configured with a dedicated hardware logic or a digital signal processor.

  5A shows an example of the waveform of the excitation signal sin ωt of the resolver 6, FIG. 5B shows the waveform of the SIN output signal sin ωt × sin θ, and FIG. 5C shows the waveform of the COS output signal sin ωt × cos θ. Here, the SIN output signal sin ωt × sin θ becomes sin θ at the timing when the instantaneous value of the excitation signal sin ωt input to the resolver 6 becomes 1 for the SIN output signal and the COS output signal output from the resolver 6, and the COS output. The signal sin ωt × cos θ becomes cos θ. FIG. 5D shows the SIN output signal sin θ and the COS output signal cos θ sampled at a timing when the excitation signal sin ωt = 1.

  The control circuit 2 is connected to a rotation angle detection timing generation circuit 10. FIG. 2 shows details of the rotation angle detection timing generation circuit 10. The rotation angle detection timing generation circuit 10 includes a rising signal detection unit 21 (detection unit of the present invention), a timing generation unit 22 (calculation unit, timing generation unit, period measurement unit), an up counter 19 and a down counter 20 (calculation unit, Timing generating means). Hereinafter, each operation will be described with reference to FIGS.

  An excitation signal VREZI is input from the excitation signal generation circuit 7 to the rising signal detection unit 21 and is input to a known comparison circuit 11. Since the voltage threshold value of the comparison circuit 11 is set to 0 V, the H level is output when the excitation signal VREZI takes a positive value as shown in FIG. 3, and the L level is output when it takes a negative value. . When the excitation signal VREZI changes from a negative value to a positive value, the output waveform from the comparison circuit 11 changes from L level to H level. This is a so-called rising waveform, and in this state, the value of the excitation signal VREZI is zero. Detecting this timing (zero cross point) is called zero cross detection.

  The output from the comparison circuit 11 is branched into two, one of which is input to the delay circuit 12. The delay circuit 12 outputs a signal delayed by a predetermined time (t1) from the input waveform (see FIG. 3). The output from the delay circuit 12 is inverted into positive and negative and is input to the AND circuit 13.

  The other output branched from the comparison circuit 11 is input to the AND circuit 13 as it is. The AND circuit 13 outputs a logical product of two well-known inputs, and with respect to the (inverted) input from the delay circuit 12 and the input from the comparison circuit 11, the waveform L of the comparison circuit 11 as shown in FIG. A pulse waveform with a pulse width of t1 is output only at the rise from the level to the H level. With this pulse waveform, the rising edge of the waveform of the comparison circuit 11 (that is, the zero cross point of the excitation signal VREZI) can be reliably detected. The AND circuit 13 outputs a pulse waveform every time the zero cross point of the excitation signal VREZI is detected, that is, every cycle of the excitation signal VREZI waveform. Therefore, the time from the rise of the pulse waveform output from the AND circuit 13 to the next rise of the pulse waveform output from the AND circuit 13 is the time of one cycle of the excitation signal VREZI waveform.

  The pulse waveform generated by the AND circuit 13 is input to an OR circuit 14 that outputs a logical sum of two known inputs. The other input of the OR circuit 14 is connected to the circuit reset signal fRES. However, the circuit reset signal fRES is always at the L level when the rotation angle detection timing generation circuit 10 is operating normally, so that the logical sum is obtained. The output from the OR circuit 14 is directly input to the RS flip-flop 15 without affecting the generation.

  When the pulse waveform from the AND circuit 13 is input to the known RS flip-flop 15 via the OR circuit 14, the RS flip-flop 15 sends a command signal (pulse signal: see FIG. 4) to the down counter 20. The down counter 20 reads the counter value from the up counter 19 and starts down counting. Details will be described below.

  The signal from the RS flip-flop 15 is also input to the known D flip-flop 16 of the timing generation unit 22. The timing generator 22 generates a delay time for clearing the counter value of the up counter 19 to zero after the counter value of the up counter 19 is read into the down counter 20 based on a command from the RS flip-flop 15. ing. Therefore, in this configuration, the D flip-flops 16, 17, and 18 are configured, but the number of D flip-flops varies depending on the delay characteristics of the D flip-flop and the counter value reading time of the down counter 20.

  As shown in FIG. 4, when the output Q of the RS flip-flop 15 becomes H level and the input D of the D flip-flop 16 is inputted with the H level and a predetermined time (for example, t2) elapses, the output Q of the D flip-flop 16 becomes It becomes H level for a predetermined time (for example, t3). The output Q of the D flip-flop 16 changes from the L level to the H level and is input to the input D of the D flip-flop 17, and after t2 hours, the output Q of the D flip-flop 17 becomes the H level for t3 time. Similarly, the output Q of the D flip-flop 18 changes from the L level to the H level, and the output Q of the D flip-flop 18 becomes the H level for t3 time after t2. The counter value of the up counter 19 is cleared to zero at the timing when the output Q of the D flip-flop 18 changes from H level to L level. That is, the time T from when the output Q of the RS flip-flop 15 becomes H level until the counter value of the up counter 19 is cleared to zero is t2 (delay time of the D flip-flop 16) + t2 (delay of the D flip-flop 17) Time) + t2 (delay time of D flip-flop 18) + t3 (H level output time of D flip-flop 18). During this time T, the counter value of the up counter 19 is read into the down counter 20.

  Further, the D flip-flops 16, 17, and 18 of the timing generation unit 22 operate based on the signal of the clock fQ. When the output Q of the D flip-flop 17 changes from the L level to the H level, this signal is input to the R1 terminal of the RS flip-flop 15, and the output Q of the RS flip-flop 15 changes from the H level to the L level. .

The up counter 19 is a well-known counter circuit, and in this embodiment, a binary 10-bit counter is used. When the circuit reset signal fRES or the reset signal from the D flip-flop 18 is input, the counter value is counted (up-counted) from 0 to 2 ¹⁰ −1 based on the signal from the clock fQ. When the counter value exceeds 2 ¹⁰ −1, counting starts again from 0 (see FIG. 3).

  When the state of the output Q of the D flip-flop 18 changes from the H level to the L level, the counter value of the up counter 19 is cleared to zero and starts counting up again from the counter value 0. Then, at the timing when the pulse waveform is output from the AND circuit 13 (that is, after the time corresponding to one period of the excitation signal VREZI waveform has elapsed), the counter is cleared again to zero and the up-counting is started again from the counter value 0 (see FIG. 3). ). Therefore, the counter value immediately before being cleared to zero is the time for one cycle of the excitation signal VREZI waveform.

The down counter 20 is also a well-known counter circuit. In this embodiment, a binary 10-bit counter is used. When a reset signal from the circuit reset signal fRES is input, the counter value 2 ¹⁰ −1 is counted (down counted) from 2 ¹⁰ −1 to 0 based on the signal from the clock fQ. When the counter value becomes 0, the counting starts again from 2 ¹⁰ -1. When the counter value is rewritten during the down count, the down count is started from the rewritten value (see FIG. 4).

  When a pulse waveform is output from the AND circuit 13, the output Q of the RS flip-flop 15 changes from L level to H level, and the information is input to the C5 terminal of the down counter 20, the down counter 20 is updated to the up counter 19. The current counter value is read out, and the counter value of the down counter 20 itself is rewritten to ¼ of the read counter value.

  In FIG. 2, the data output unit 19a of the up-counter 19 and the data input unit 20a of the down-counter 20 are arranged in order of b0, b1,..., B9 ([512] position from the least significant bit (position [1]). ) When a bit name is given, b2 ([4]) of the data output unit 19a of the up counter 19 is connected to b0 ([1]) of the data input unit 20a of the down counter 20, and the data output unit 19a of the up counter 19 B9 ([512]) is connected to b7 ([128]) of the data input unit 20a of the down counter 20, and in the down counter 20, the value of the up counter 19 is shifted to the lower bit side by 2 bits. The counter value is read in the form.

  For example, when “1010111100” (700 in decimal) is shifted by 2 bits to the lower bit side in binary, the lower 2 bits are truncated to “10101111” to 135 in decimal, which is 1 of the original value (700). / 4. As shown in FIG. 2, by connecting the data output unit 19a of the up counter 19 and the data input unit 20a of the down counter 20, it is possible to easily obtain a time corresponding to ¼ period of the excitation signal VREZI waveform.

When the down-counting is restarted based on the counter value of the up-counter 19 and the counter value reaches 0, the down-counter 20 starts down-counting again from the counter value 2 ¹⁰ -1 and the 1/4 time timing output terminal f1 / 4REZ. A predetermined pulse waveform is output to the control circuit 2 (see FIG. 3).

  When the pulse waveform from the 1/4 time timing output terminal f1 / 4REZ is input, the control circuit 2 takes in the SIN output signal and the COS output signal from the resolver 6. Then, the rotation angle of the motor 1 is calculated based on the SIN output signal and the COS output signal, the state of the motor 1 is detected from the rotation angle, and whether or not the operation according to the control command from the control circuit 2 is performed. Determination is performed, and drive control such as issuing a new control command to the motor 1 is performed based on the determination result.

(Application example to electric power steering system)
The rotation angle detection timing generation device and rotation angle detection timing generation method of the present invention are also suitable for an electric power steering (EPS) device of a vehicle. FIG. 6 is a schematic configuration diagram of the electric power steering apparatus 101. The steering handle 110 is connected to the steering shaft 112 a, the lower end of the steering shaft 112 a is connected to the torque sensor 111 that detects the movement of the driver's steering handle 110, and the upper end of the pinion shaft 112 b is connected to the torque sensor 111. Has been. A pinion (not shown) is provided at the lower end of the pinion shaft 112b, and this pinion is meshed with the rack bar 118 in the steering gear box 116. Further, one end of a tie rod 120 is connected to both ends of the rack bar 118, and a steered wheel 124 is connected to the other end of each tie rod 120 via a knuckle arm 122. An electric motor 115 is attached to the pinion shaft 112b via a gear (not shown). The electric motor 115 may be attached to the rack bar 118 coaxially.

  The steering control unit 130 includes a well-known CPU 131, RAM 132, ROM 133, I / O 134 which is an input / output interface, and a bus line 135 which connects these components. The CPU 131 controls the program and data stored in the ROM 133 and the RAM 132. The ROM 133 has a program storage area 133a and a data storage area 133b. An EPS control program 133p is stored in the program storage area 133a. Data necessary for the operation of the EPS control program 133p is stored in the data storage area 133b.

  In the steering control unit 130, the CPU 131 executes the EPS control program stored in the ROM 133, thereby driving generated by the electric motor 115 corresponding to the torque detected by the torque sensor 111 and the steering angle detected by the steering angle sensor 113. Torque is calculated, and a voltage for generating the calculated drive torque is applied to the electric motor 115 via the motor driver 114. At this time, the rotation angle of the electric motor 115 is detected by the resolver 109 to check whether the rotation corresponding to the driving torque is performed, and the voltage applied to the electric motor 115 is obtained according to the result.

  Thus, since the resolver 109 is used in the electric power steering apparatus 101, the rotation angle of the electric motor 115 is adjusted by the resolver 109 by using the rotation angle detection timing generation apparatus and the rotation angle detection timing generation method of the present invention. Measurement can be performed with high accuracy, and as a result, the control accuracy of the electric power steering apparatus 101 is improved.

  Although the embodiments of the present invention have been described above, these are merely examples, and the present invention is not limited to these embodiments, and the knowledge of those skilled in the art can be used without departing from the spirit of the claims. Various modifications based on this are possible.

The block diagram which shows an example of the control apparatus of the three-phase brushless DC motor to which the rotation angle detection timing generation apparatus and rotation angle detection timing generation method of this invention are applied. The block diagram which shows an example of the rotation angle detection timing generation circuit of this invention. The timing chart which showed the detail of the output signal of each part of a rotation angle detection timing generation circuit. The timing chart which showed the detail of the delay output signal. The timing chart shown about the signal of each part of a resolver. The block diagram which shows an example of an electric power steering control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Three-phase brushless DC motor 2 Control circuit 3 Drive circuit 4,5 Current sensor 6 Resolver 7 Excitation signal generation circuit (excitation signal supply means)
10 Rotation angle detection timing generation circuit (calculation means, timing generation means, period measurement means)
DESCRIPTION OF SYMBOLS 11 Comparison circuit 12 Delay circuit 13 AND circuit 14 OR circuit 15 RS flip-flop 16, 17, 18 D flip-flop 19 Up counter (calculation means, timing generation means)
20 Down counter (calculation means, timing generation means)
21 Rising signal detector (detection means, detection circuit)
22 Timing generator (calculation means, timing generation means, period measurement means,
101 Electric power steering control device

Claims (8)

A resolver that generates two types of output signals having a predetermined phase difference from each other according to the rotation angle of the rotating body;
Excitation signal supply means for generating an excitation signal that is a sine wave for generating the two types of output signals, and supplying the generated excitation signal to the resolver;
Detecting means for detecting a predetermined phase timing of the excitation signal;
Period measuring means for measuring the period of the excitation signal;
Based on the period of the excitation signal measured by the period measurement means, calculation means for calculating a time from the predetermined phase timing until the excitation signal becomes maximum,
Timing generating means for generating a timing for measuring the two types of output signals when a time calculated by the calculating means has elapsed from the predetermined phase timing;
A rotation angle detection timing generation device comprising:   The rotation angle detection timing generation device according to claim 1, wherein the detection unit, the period measurement unit, the calculation unit, and the timing generation unit are configured by a digital logic circuit.   The timing generation means includes a delay period generation circuit that generates a delay period from detection of the predetermined phase timing to clearing the period of the excitation signal, and generates the timing during the delay period. The rotation angle detection timing generation device according to claim 1 or 2.   4. The method according to claim 1, which is applied to a control device for an electric power steering apparatus including an electric motor for assisting a driver's steering operation, and is used for detecting a rotation angle of the electric motor. The rotation angle detection timing generation device described. A first step that is input to a resolver that generates two types of output signals having a predetermined phase difference between each other according to the rotation angle of the rotating body;
A second step of measuring a period of an excitation signal that is a sine wave for generating the two types of output signals;
A third step of obtaining a time until the excitation signal becomes maximum based on a predetermined phase timing of the excitation signal from the cycle;
A fourth step of generating a timing for measuring the two kinds of output signals when the calculated time elapses from a predetermined phase timing of the excitation signal;
A rotation angle detection timing generation method comprising:   The rotation angle detection timing generation method according to claim 5, wherein the generation of the timing is performed during a delay period from when the predetermined phase timing is detected to when the period of the excitation signal is cleared.   The rotation angle detection according to claim 5 or 6, which is applied to a control device of an electric power steering device provided with an electric motor for assisting a driver's steering operation, and is used for detecting a rotation angle of the electric motor. Timing generation method.   The rotation angle detection timing generation device or the rotation angle detection timing generation method according to any one of claims 1 to 7, wherein the predetermined phase timing is a time when the predetermined phase timing rises from zero.

Images