Angle detection signal processing device

Abstract

To provide an angle detection signal processing device capable of outputting digital angle data regardless of whether the pair of angle detection signals includes a carrier wave component or not.SOLUTION: The angle detection signal processing device is an angle detection signal processing device to which a pair of angle detection signals output from the angle detection device, the pair of angle detection signals are converted into digital angle using a phase-locked loop method, and outputs the digital angle data. The angle detection signal processing device includes: a phase lock unit 4; and a switching operation unit 1 that is placed at the input side of the phase lock unit 4, to which a pair of angle detection signals is input. The switching operation unit 1 is configured so as to, when the pair of angle detection signals does not include a carrier wave component, each of the pair of angle detection signals is inverted at a preset frequency and output, and when the pair of angle detection signals includes a carrier wave component, each of the pair of angle detection signals is output without being inverted at a preset frequency.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an angle detection signal processing device. [Background technology]

[0002] Conventionally, there is known an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device and performs digital angle conversion on the pair of angle detection signals using a phase-locked loop method. The angle detection signal processing device has a pair of phase lock units and a phase difference calculation unit. Each phase lock unit uses a pair of angle detection signals including a carrier wave component to output phase angle data corresponding to digital angle data. The phase difference calculation unit calculates the difference between the phase angle data output from each phase lock unit and outputs the calculated value as digital angle data (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-58232 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of the angle detection signal processing device described in Patent Document 1, when a pair of angle detection signals does not contain a carrier wave component, the phase lock unit cannot output phase angle data corresponding to the digital angle data, which poses a problem that the angle detection signal processing device cannot output digital angle data.

[0005] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an angle detection signal processing device that can output digital angle data regardless of whether a pair of angle detection signals are signals including a carrier wave component or not. [Means for solving the problem]

[0006] The angle detection signal processing device according to the present invention is an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device, performs phase-locked loop digital angle conversion on the pair of angle detection signals, and outputs digital angle data, and includes a phase lock unit and a switching operation unit that is provided on the input side of the phase lock unit and receives the pair of angle detection signals as input. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching operation unit inverts each of the pair of angle detection signals at a predetermined frequency and outputs them, and when the pair of angle detection signals are signals that contain a carrier wave component, the switching operation unit outputs each of the pair of angle detection signals at the predetermined frequency without inverting them. In the angle detection signal processing device of the present invention, a switching operation unit is configured to input a switching control signal, and the polarity of the switching control signal changes at a predetermined frequency when the pair of angle detection signals are signals that do not contain a carrier wave component, and the polarity of the switching control signal remains constant when the pair of angle detection signals are signals that contain a carrier wave component, and the switching operation unit inverts and outputs the pair of angle detection signals in response to the change in polarity of the switching control signal. The angle detection signal processing device according to the present invention is an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device, performs phase-locked loop digital angle conversion on the pair of angle detection signals, and outputs digital angle data, and includes a phase lock unit and a switching operation unit that is provided inside the phase lock unit and receives a control deviation signal as input. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching operation unit inverts the control deviation signal at a predetermined frequency and outputs it, and when the pair of angle detection signals are signals that contain a carrier wave component, the switching operation unit outputs the control deviation signal at the predetermined frequency without inverting it. In the angle detection signal processing device according to the present invention, a switching control signal is input to the switching operation unit, and the polarity of the switching control signal changes at a preset frequency when the pair of angle detection signals are signals that do not contain a carrier wave component, and the polarity remains constant when the pair of angle detection signals are signals that contain a carrier wave component, and the switching operation unit inverts and outputs a control deviation signal in response to the change in polarity of the switching control signal. In the angle detection signal processing device according to the present invention, the switching operation unit is provided on the input side of the control law in the phase lock unit. In the angle detection signal processing device according to the present invention, the preset frequency is a frequency that coincides with the reference frequency used in the phase lock unit. In the angle detection signal processing device according to the present invention, the switching operation section is composed of a digital circuit. [Effects of the Invention]

[0007] According to the angle detection signal processing device of the present invention, digital angle data can be output regardless of whether the pair of angle detection signals are signals containing a carrier wave component or not. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an angle detection signal processing device according to a first embodiment. [Figure 2] 2 is a graph showing an example of a switching control signal of FIG. 1; [Figure 3] FIG. 1 is a block diagram showing an angle detection signal processing device of a first comparative example. [Figure 4] FIG. 10 is a block diagram showing an angle detection signal processing device according to a second embodiment. [Figure 5] FIG. 10 is a block diagram showing an angle detection signal processing device according to a third embodiment. [Figure 6] FIG. 10 is a block diagram showing an angle detection signal processing device of a second comparative example. [Figure 7]FIG. 10 is a block diagram showing an angle detection signal processing device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiment 1 FIG. 1 is a block diagram showing an angle detection signal processing device according to a first embodiment. The angle detection signal processing device according to the first embodiment receives a pair of angle detection signals output from an angle detection device (not shown) and performs digital angle conversion of the pair of angle detection signals using a phase-locked loop method. One of the pair of angle detection signals is designated as a first angle detection signal V I and the other angle detection signal is a second angle detection signal V Q Let's say.

[0010] The angle detection signal processing device includes a switching operation unit 1, a switching operation unit 2, a signal processing unit 3, a phase lock unit 4, a phase lock unit 5, and a phase difference calculation unit 6.

[0011] The switching operation unit 1 receives a first angle detection signal V output from the angle detection device. I is input to the switching operation unit 1. A switching control signal output from an external device (not shown) is also input to the switching operation unit 1. The polarity of the switching control signal changes at a preset frequency ω0 when the pair of angle detection signals are signals that do not contain a carrier component, and the polarity is constant when the pair of angle detection signals are signals that contain a carrier component. The frequency ω0 matches the frequency of the carrier component when the pair of angle detection signals are signals that contain a carrier component. Therefore, the frequency ω0 matches the reference frequency used in the phase lock units 4 and 5.

[0012] The switching operation unit 1 changes the first angle detection signal V ISpecifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 1 inverts and outputs the first angle detection signal V I is inverted at frequency ω0 and is the output signal V IS On the other hand, when the pair of angle detection signals are signals containing a carrier wave component, the switching operation unit 1 outputs the first angle detection signal V I The output signal V of the switching operation unit is not inverted at the frequency ω0. IS Output as

[0013] The switching operation unit 2 receives the second angle detection signal V output from the angle detection device. Q is input to the switching operation unit 2. Similarly to the switching operation unit 1, a switching control signal output from an external device is input to the switching operation unit 2. The switching control signal input to the switching operation unit 2 is the same signal as the switching control signal input to the switching operation unit 1.

[0014] The switching operation unit 2 generates a second angle detection signal V Q Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 2 inverts and outputs the second angle detection signal V Q is inverted at frequency ω0 and is the output signal V QS On the other hand, when the pair of angle detection signals are signals containing a carrier wave component, the switching operation unit 2 outputs the second angle detection signal V Q The output signal V of the switching operation unit is not inverted at the frequency ω0. QS Output as

[0015] Each of the switching operation unit 1 and the switching operation unit 2 is configured by an analog circuit.

[0016] FIG. 2 is a graph showing an example of the switching control signal of FIG. 1. The switching control signal is output from a control signal generating unit in an external device. The control signal generating unit outputs a signal that becomes a square wave with a frequency of ω0 or a signal with a preset fixed value as the switching control signal. When the switching control signal is a signal that becomes a square wave with a frequency of ω0, the polarity of the switching control signal changes at the frequency ω0. On the other hand, when the switching control signal is a signal with a fixed value, the polarity of the switching control signal is constant. FIG. 2 shows a case where the switching control signal is a signal that becomes a square wave with a frequency of ω0.

[0017] The signal processing unit 3 receives the switching operation unit output signal V IS and the switching operation unit output signal V QS The signal processing unit 3 receives the switching operation unit output signal V IS and the switching operation unit output signal V QS is output to the phase lock unit 4 as it is. In addition, the signal processing unit 3 outputs the switching operation unit output signal V IS is output to the phase lock unit 5 as is, and the switching operation unit output signal V QS is inverted and output to the phase lock unit 5.

[0018] The phase lock unit 4 includes a signal processing unit 41 , a control law 42 , and a phase angle data generating unit 43 .

[0019] The signal processing unit 41 includes a multiplication unit 411 , a multiplication unit 412 , an addition unit 413 , and a signal generation unit 414 .

[0020] The multiplication unit 411 receives the switching operation unit output signal V output from the signal processing unit 3. IS is input, and a signal generating unit output signal V (to be described later) is output from the signal generating unit 414. UO-Q The multiplication unit 411 receives the switching operation unit output signal V IS and the signal generator output signal V UO-Q and output the multiplied signal to the adder 413.

[0021] The multiplication unit 412 receives the switching operation unit output signal V output from the signal processing unit 3. QS is input, and a signal generating unit output signal V (to be described later) is output from the signal generating unit 414. UO-I The multiplication unit 412 receives the switching operation unit output signal V QS and the signal generator output signal V UO-I and output the multiplied signal to the adder 413.

[0022] The adder 413 outputs the switching operation unit output signal V IS and the signal generator output signal V UO-Q The signal obtained by multiplying these signals and the switching operation unit output signal V QS and the signal generator output signal V UO-I The adder 413 adds the sum of the signals obtained by multiplying the control deviation signal V UC Output as

[0023] The signal generator 414 receives a phase angle data generator output signal PA1 (described later) output from the phase angle data generator 43. The signal generator 414 generates a signal generator output signal V that has a phase angle according to the phase angle data generator output signal PA1 and is orthogonal to each other. UO-Q and the signal generator output signal V UO-I The signal generator output signal V UO-Q is -sin(ω0t+φ), and the signal generator output signal V UO-I becomes cos(ω0t+φ).

[0024] The control law 42 includes the control deviation signal V UC The control law 42 is configured as a filter circuit that amplifies the control deviation signal V with a predetermined transfer characteristic such as PI compensation. UC The feedback control signal V is used to perform negative feedback control so that f1 Output.

[0025] The phase angle data generating unit 43 includes a signal generating unit 431 and a counter 432 .

[0026] The signal generator 431 receives the feedback control signal V f1 The signal generator 431 receives the feedback control signal V f1 The signal generator outputs an output signal having a frequency according to the signal.

[0027] Counter 432 receives the signal generation unit output signal output from signal generation unit 431. Counter 432 divides the frequency of the signal generation unit output signal, counts the number of pulses, and outputs the count value as phase angle data generation unit output signal PA1.

[0028] The phase lock unit 5 includes a signal processing unit 51 , a control law 52 , and a phase angle data generating unit 53 .

[0029] The signal processing unit 51 includes a multiplication unit 511 , a multiplication unit 512 , an addition unit 513 , and a signal generation unit 514 .

[0030] The multiplication unit 511 receives the switching operation unit output signal V output from the signal processing unit 3. IS is input, and a signal generating unit output signal V (to be described later) is output from the signal generating unit 514. LO-Q The multiplication unit 511 receives the switching operation unit output signal V IS and the signal generator output signal V LO-Q and output the multiplied signal to the adder 513.

[0031] The multiplication unit 512 receives the inverted switching operation unit output signal V output from the signal processing unit 3. QS is inverted and input, and the signal generating unit output signal V LO-I The multiplication unit 512 receives the inverted switching operation unit output signal -V QS and the signal generator output signal V LO-I and output the multiplied signal to the adder 513.

[0032] The adder 513 outputs the switching operation unit output signal V ISand the signal generator output signal V LO-Q The signals multiplied by each other and the inverted switching operation unit output signal -V QS and the signal generator output signal V LO-I The adder 513 adds the signals obtained by multiplying the signals by the control deviation signal V LC Output as

[0033] The signal generator 514 receives a phase angle data generator output signal PA2 (described later) output from the phase angle data generator 53. The signal generator 514 generates a signal generator output signal V that has a phase angle according to the phase angle data generator output signal PA2 and is orthogonal to each other. LO-Q and the signal generator output signal V LO-I The signal generator output signal V LO-Q is -sin(ω0t-φ), and the signal generator output signal V LO-I becomes cos(ω0t-φ).

[0034] The control law 52 includes the control deviation signal V LC The control law 52 is configured as a filter circuit that amplifies the control deviation signal V with a predetermined transfer characteristic such as PI compensation. LC The feedback control signal V is used to perform negative feedback control so that f2 Output.

[0035] The phase angle data generating unit 53 includes a signal generating unit 531 and a counter 532 .

[0036] The signal generator 531 receives the feedback control signal V f2 The signal generator 531 receives the feedback control signal V f2 The signal generator outputs an output signal having a frequency according to the signal.

[0037] Counter 532 receives the signal generation unit output signal output from signal generation unit 531. Counter 532 divides the frequency of the signal generation unit output signal, counts the number of pulses, and outputs the count value as phase angle data generation unit output signal PA2.

[0038] The phase difference calculation unit 6 receives the phase angle data generation unit output signal PA1 output from the counter 432 and the phase angle data generation unit output signal PA2 output from the counter 532. The phase difference calculation unit 6 calculates the difference between the phase angle data generation unit output signal PA1 and the phase angle data generation unit output signal PA2, and outputs the calculated value as digital angle data φ.

[0039] Next, the operation of the angle detection signal processing device when the pair of angle detection signals output from the angle detection device are signals containing a carrier component of frequency ω0 will be described. I is cosω0t×cosθ, and the second angle detection signal V Q is cosω0t×sinθ, where θ is the angle detected by the angle detection device.

[0040] When the pair of angle detection signals are signals containing a carrier wave component, switching control signals with constant polarity are input to the switching operation unit 1 and the switching operation unit 2. In this case, the control deviation signal V UC is calculated by the following formula (1), and the control deviation signal V LC is calculated by the following formula (2).

[0041] V UC =V I ×V UO-Q +V Q ×V UO-I =-cosω0t×cosθ×sin(ω0t+φ)+cosω0t×sinθ×cos(ω0t+φ) =1 / 2{sin(θ-φ)-sin(2ω0t-θ+φ)} (1) V LC =V I ×V LO-Q-V Q ×V LO-I =-cosω0t×cosθ×sin(ω0t-φ)-cosω0t×sinθ×cos(ω0t-φ) =1 / 2{sin(-θ+φ)-sin(2ω0t+θ-φ)} (2)

[0042] In both equations (1) and (2) above, the second term is a high frequency component at frequency 2ω0, which is attenuated by the filtering effect of control law 42 and control law 52. This causes sin(θ-φ) in equation (1) above to be attenuated by the feedback control signal V f1 The sin(-θ+φ) of (2) above is the feedback control signal V f2 As a result, in the phase lock units 4 and 5, negative feedback control is performed so that θ=φ.

[0043] Next, the operation of the angle detection signal processing device when the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component will be described. I is cosθ, and the second angle detection signal V Q Let be sinθ.

[0044] When the pair of angle detection signals are signals that do not contain a carrier wave component, a switching control signal whose polarity changes at a frequency ω0 is input to the switching operation unit 1 and the switching operation unit 2. As long as the switching control signal has a frequency that matches the frequency ω0, there are no restrictions on the H / L duty and phase. Therefore, the H / L duty is set to 50:50 and the phase is set to π / 2. In this case, the switching operation unit 1 generates the first angle detection signal V I is multiplied by a square wave of frequency ω0, and the switching operation unit 2 generates a second angle detection signal V Q is multiplied by a square wave of frequency ω0.

[0045] The square wave of frequency ω0 contains the fundamental frequency and odd-order high-frequency components. Therefore, the switching operation unit output signal V ISis calculated by the following formula (3), and the switching operation unit output signal V QS is calculated by the following formula (4).

[0046] V IS =V I ×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =-4 / π×cosθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =-4 / π×cosθ×cosω0t+4 / 3π×cosθ×cos3ω0t-4 / 5π×cosθ×cos5ω0t···(3) V QS =V Q ×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =4 / π×sinθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =4 / π×sinθ×cosω0t-4 / 3π×sinθ×cos3ω0t+4 / 5π×sinθ×cos5ω0t···(4)

[0047] Using the above equations (3) and (4), the control deviation signal V UC is calculated by the following equation (5), and the control deviation signal V LC is calculated by the following formula (6).

[0048] V UC =V IS ×V UO-Q +V QS ×V UO-I =-4 / π×cosθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...}×sin(ω0t+φ)+4 / π×sinθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...}×cos(ω0t+φ) =2 / π×{sin(θ-φ)-sin(2ω0t-θ+φ)-1 / 3×sin(2ω0t+θ-φ)+1 / 3×sin(4ω0t-θ+φ)+1 / 5×sin(4ω0t+θ-φ)-1 / 5×sin(6ω0t+θ-φ)...} (5) V LC =V IS ×V LO-Q -V QS ×V LO-I =-4 / π×cosθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...}×sin(ω0t-φ)-4 / π×sinθ×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...}×cos(ω0t-φ) =2 / π×{sin(-θ+φ)+sin(2ω0t+θ-φ)+1 / 3×sin(2ω0t-θ+φ)-1 / 3×sin(4ω0t+θ-φ)+1 / 5×sin(4ω0t-θ+φ)+1 / 5×sin(6ω0t+θ-φ)...} (6)

[0049] In both the above equations (5) and (6), the second and subsequent terms are high-frequency components with a frequency of 2ω0 or higher, and are attenuated by the filter effect of control law 42 and control law 52. As a result, sin(θ-φ) in the above equation (5) is converted into the feedback control signal V f1 The sin(-θ+φ) of (6) above is the feedback control signal V f2 As a result, in the phase lock units 4 and 5, negative feedback control is performed so that θ=φ.

[0050] Next, an angle detection signal processing device of a first comparative example will be described. Fig. 3 is a block diagram showing the angle detection signal processing device of the first comparative example. Unlike the angle detection signal processing device according to embodiment 1, the angle detection signal processing device of the first comparative example does not include a switching operation unit 1 and a switching operation unit 2. The other configurations of the angle detection signal processing device of the first comparative example are similar to the configurations of the angle detection signal processing device according to embodiment 1.

[0051] The operation of the angle detection signal processing device of the first comparative example when the pair of angle detection signals output from the angle detection device are signals including a carrier wave component is similar to the operation of the angle detection signal processing device according to the first embodiment.

[0052] When the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component, the angle detection signal processing device of the first comparative example generates a control deviation signal V UC is calculated by the following equation (7), and the control deviation signal V LC is calculated by the following formula (8).

[0053] V UC =V I ×V UO-Q +V Q ×V UO-I =-cosθ×sin(ω0t+φ)+sinθ×cos(ω0t+φ) =sin(θ-ω0t-φ) (7) V LC =V I ×V LO-Q -V Q ×V LO-I =-cosθ×sin(ω0t-φ)-sinθ×cos(ω0t-φ) =sin(-θ+ω0t+φ) (8)

[0054] In both equations (7) and (8) above, the control error signal V UC and the control deviation signal V LC is composed only of high frequency components of frequency ω0 and is attenuated by the filter effect of control law 42 and control law 52. As a result, the feedback control signal V f1 and the feedback control signal V f2are constant regardless of θ. As a result, the phase lock units 4 and 5 cannot perform negative feedback control so that θ = φ. In other words, in the angle detection signal processing device of the first comparative example, when a pair of angle detection signals is a signal that does not contain a carrier wave component, the phase lock units 4 and 5 cannot output phase angle data corresponding to the digital angle data φ. As a result, the angle detection signal processing device of the first comparative example cannot output the digital angle data φ.

[0055] On the other hand, in the angle detection signal processing device according to embodiment 1, the phase lock units 4 and 5 can output phase angle data corresponding to the digital angle data φ regardless of whether the pair of angle detection signals contain a carrier wave component. As a result, the angle detection signal processing device according to embodiment 1 can output the digital angle data φ regardless of whether the pair of angle detection signals contain a carrier wave component.

[0056] As described above, the angle detection signal processing device according to the first embodiment is an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device and performs digital angle conversion on the pair of angle detection signals using a phase-locked loop system. The angle detection signal processing device includes a phase lock unit 4, a phase lock unit 5, and a switching operation unit 1 and a switching operation unit 2 that are located on the input side of the phase lock units 4 and 5 and receive the pair of angle detection signals. When the pair of angle detection signals do not contain a carrier wave component, the switching operation unit 1 and the switching operation unit 2 invert each of the pair of angle detection signals at a frequency ω0 and output the inverted signals. When the pair of angle detection signals contain a carrier wave component, the switching operation unit 1 and the switching operation unit 2 output each of the pair of angle detection signals without inverting them at a frequency ω0. This configuration allows the angle detection signal processing device to output digital angle data φ regardless of whether the pair of angle detection signals contain a carrier wave component.

[0057] Furthermore, in the angle detection signal processing device according to the first embodiment, switching operation units 1 and 2 are configured to receive switching control signals. The switching control signals change polarity at a frequency ω0 when the pair of angle detection signals are signals that do not contain a carrier component, and have a constant polarity when the pair of angle detection signals are signals that contain a carrier component. The switching operation units 1 and 2 invert and output the pair of angle detection signals in response to the change in polarity of the switching control signal. With this simple configuration, the switching operation units 1 and 2 can invert and output each of the pair of angle detection signals at a frequency ω0 when the pair of angle detection signals are signals that do not contain a carrier component.

[0058] Furthermore, in the angle detection signal processing device according to the first embodiment, the frequency ω0 is a frequency that matches the reference frequency used in the phase lock units 4 and 5. With this configuration, there is no need to provide a new signal generating unit for generating the switching control signal. This simplifies the configuration of the angle detection signal processing device.

[0059] In the angle detection signal processing device according to the first embodiment, the switching operation unit 1 and the switching operation unit 2 are configured with analog circuits. However, this configuration is not limiting. The switching operation unit 1 and the switching operation unit 2 may be configured with digital circuits. In this case, digital data processing of the pair of angle detection signals is performed before the pair of angle detection signals are input to the switching operation unit 1 and the switching operation unit 2. When the switching operation unit 1 and the switching operation unit 2 are configured with digital circuits, it is possible to suppress the superposition of an error signal on the pair of angle detection signals due to an imbalance in switching characteristics.

[0060] Embodiment 2 4 is a block diagram showing an angle detection signal processing device according to embodiment 2. In the angle detection signal processing device according to embodiment 2, a switching operation unit 1 is provided inside a phase lock unit 4, and a switching operation unit 2 is provided inside a phase lock unit 5.

[0061] The switching operation unit 1 receives the control deviation signal V output from the adder 413. UC is input. A switching control signal output from an external device is input to the switching operation unit 1. The switching control signal changes polarity at a frequency ω0 when the pair of angle detection signals are signals that do not contain a carrier wave component, and the polarity is constant when the pair of angle detection signals are signals that contain a carrier wave component.

[0062] The switching operation unit 1 generates a control deviation signal V in response to a change in the polarity of the switching control signal. UC Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 1 inverts and outputs the control deviation signal V UC is inverted at frequency ω0 and is the output signal V SUC On the other hand, when the pair of angle detection signals contains a carrier wave component, the switching operation unit 1 outputs the control deviation signal V UC The output signal V of the switching operation unit is not inverted at the frequency ω0. SUC The switching operation unit output signal V output from the switching operation unit 1 is SUC is input to the control law 42.

[0063] The switching operation unit 2 receives the control deviation signal V output from the adder 513. LC A switching control signal output from an external device is input to the switching operation unit 2. The switching control signal input to the switching operation unit 2 is the same signal as the switching control signal input to the switching operation unit 1.

[0064] The switching operation unit 2 generates a control deviation signal V in response to a change in the polarity of the switching control signal. LC Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 2 inverts and outputs the control deviation signal V LC is inverted at frequency ω0 and is the output signal V SLC On the other hand, when the pair of angle detection signals contains a carrier wave component, the switching operation unit 2 outputs the control deviation signal V LC The output signal V of the switching operation unit is not inverted at the frequency ω0. SLC The switching operation unit output signal V output from the switching operation unit 2 is SLC is input to the control law 52.

[0065] Other configurations of the angle detection signal processing device according to the second embodiment are the same as those of the angle detection signal processing device according to the first embodiment.

[0066] Next, the operation of the angle detection signal processing device when a pair of angle detection signals output from the angle detection device is a signal containing a carrier component of frequency ω0 will be described. As a pair of angle detection signals containing a carrier component of frequency ω0, a first angle detection signal V I is cosω0t×cosθ, and the second angle detection signal V Q is cosω0t×sinθ, where θ is the angle detected by the angle detection device.

[0067] When the pair of angle detection signals are signals containing a carrier wave component, switching control signals with constant polarity are input to the switching operation unit 1 and the switching operation unit 2. In this case, the switching operation unit output signal V SUC is calculated by the following equation (9), and the switching operation unit output signal V SLC is calculated by the following formula (10).

[0068] V SUC =V UC =-cosω0t×cosθ×sin(ω0t+φ)+cosω0t×sinθ×cos(ω0t+φ) =1 / 2{sin(θ-φ)-sin(2ω0t-θ+φ)} (9) V SLC =V LC =-cosω0t×cosθ×sin(ω0t-φ)-cosω0t×sinθ×cos(ω0t-φ) =1 / 2{sin(-θ+φ)-sin(2ω0t+θ-φ)} (10)

[0069] In both equations (9) and (10) above, the second term is a high frequency component at frequency 2ω0, which is attenuated by the filtering effect of control law 42 and control law 52. This causes sin(θ-φ) in equation (9) above to be converted into the feedback control signal V f1 The sin(-θ+φ) in (10) above is the feedback control signal V f2 As a result, in the phase lock units 4 and 5, negative feedback control is performed so that θ=φ.

[0070] Next, the operation of the angle detection signal processing device when the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component will be described. I is cosθ, and the second angle detection signal V Q Let be sinθ.

[0071] When the pair of angle detection signals are signals that do not contain a carrier wave component, a switching control signal whose polarity changes at a frequency ω0 is input to the switching operation unit 1 and the switching operation unit 2. As long as the switching control signal has a frequency that matches the frequency ω0, there are no restrictions on the H / L duty and phase. Therefore, the H / L duty is set to 50:50 and the phase is set to π / 2. In this case, the switching operation unit 1 generates a control deviation signal V UC is multiplied by a square wave of frequency ω0, and the control deviation signal V LC is multiplied by a square wave of frequency ω0.

[0072] The square wave of frequency ω0 contains the fundamental frequency and odd-order high-frequency components. Therefore, the switching operation unit output signal V SUC is calculated by the following equation (11), and the switching operation unit output signal V SLC is calculated by the following equation (12). V SUC =V UC ×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =sin(θ-ω0t-φ)×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =2 / π×{sin(θ-φ)-sin(2ω0t-θ+φ)-1 / 3×sin(2ω0t+θ-φ)+1 / 3×sin(4ω0t-θ+φ)+1 / 5×sin(4ω0t+θ-φ)-1 / 5×sin(6ω0t+θ-φ)-. V SLC =V LC ×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} =sin(-θ+ω0t+φ)×4 / π×{cosω0t-1 / 3×cos3ω0t+1 / 5×cos5ω0t-...} = 2 / π

[0073] In both the above equations (11) and (12), the second and subsequent terms are high-frequency components with a frequency of 2ω0 or higher, and are attenuated by the filter effect of control law 42 and control law 52. As a result, sin(θ-φ) in the above equation (11) is converted into the feedback control signal V f1 The sin(-θ+φ) in (12) above is the feedback control signal V f2 As a result, in the phase lock units 4 and 5, negative feedback control is performed so that θ=φ.

[0074] When the switching operation unit 1 and the switching operation unit 2 are configured with analog circuits, an imbalance may occur due to the switching operation. However, in the angle detection processing device according to the second embodiment, the control deviation signal V UC and the control deviation signal V LC Since the phase-locked loop is switched, no imbalance occurs due to the switching operation, and angle errors are suppressed.

[0075] As described above, the angle detection signal processing device according to the second embodiment is an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device and performs digital angle conversion of the pair of angle detection signals using a phase-locked loop method. The angle detection signal processing device includes a phase lock unit 4, a phase lock unit 5, and a control deviation signal V UC and a phase lock unit 5 that receives a control deviation signal V LC The switching operation unit 1 receives the control deviation signal V when the pair of angle detection signals do not contain a carrier wave component. UC is inverted at a frequency ω0 and output. When the pair of angle detection signals contains a carrier wave component, the switching operation unit 1 inverts the control deviation signal V UC is output without being inverted at the frequency ω0. When the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 2 outputs the control deviation signal V LC When the pair of angle detection signals contains a carrier wave component, the switching operation unit 2 inverts the control deviation signal V LC is output without being inverted at the frequency ω. With this configuration, the angle detection signal processing device can output the digital angle data φ regardless of whether the pair of angle detection signals are signals that include a carrier wave component or not.

[0076] In the angle detection signal processing device according to the second embodiment, a switching control signal is input to the switching operation unit 1 and the switching operation unit 2. The polarity of the switching control signal changes at a frequency ω0 when the pair of angle detection signals are signals that do not contain a carrier wave component, and the polarity is constant when the pair of angle detection signals are signals that contain a carrier wave component. The switching operation unit 1 generates a control deviation signal V in response to the change in polarity of the switching control signal. UC The switching operation unit 2 inverts and outputs the control deviation signal V LC According to this configuration, the switching operation unit 1 and the switching operation unit 2 can invert and output the control deviation signal V when the pair of angle detection signals are signals that do not contain a carrier wave component with a simple configuration. UC and the control deviation signal V LC Each of these can be inverted at a frequency ω0 and output.

[0077] Furthermore, in the angle detection signal processing device according to the second embodiment, the switching operation unit 1 is provided on the input side of the control law 42 in the phase lock unit 4, and the switching operation unit 2 is provided on the input side of the control law 52 in the phase lock unit 5. With this configuration, no imbalance due to switching operation occurs in the phase locked loop, and angle errors can be suppressed. As a result, the angle detection signal processing device can output highly accurate digital angle data φ.

[0078] Embodiment 3 5 is a block diagram showing an angle detection signal processing device according to embodiment 3. One of the pair of angle detection signals is designated as a first angle detection signal V C and the other angle detection signal is a second angle detection signal V S Let's say.

[0079] The angle detection signal processing device according to the third embodiment includes a switching operation unit 1, a switching operation unit 2, a phase lock unit 7, a reference signal generation unit 8, and a switching control signal generation unit 9.

[0080] The switching operation unit 1 receives a first angle detection signal V output from the angle detection device. C The switching operation unit 1 also receives a switching control signal output from a switching control signal generation unit 9. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching control signal is a signal having a predetermined frequency ω R The polarity changes at frequency ω, and the polarity is constant when the pair of angle detection signals contains a carrier wave component. R is equal to the frequency of the carrier component when the pair of angle detection signals includes the carrier component. R is a frequency that matches the reference frequency used in the phase lock unit 7.

[0081] The switching operation unit 1 changes the first angle detection signal V C Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 1 inverts and outputs the first angle detection signal V C is the frequency ω R The signal inverted by the switching operation part is output signal V CS On the other hand, when the pair of angle detection signals are signals containing a carrier wave component, the switching operation unit 1 outputs the first angle detection signal V C is the frequency ω R The switching operation part output signal V CS Output as

[0082] The switching operation unit 2 receives the second angle detection signal V output from the angle detection device. S is input to the switching operation unit 2. Similarly to the switching operation unit 1, the switching operation unit 2 is also configured to receive a switching control signal output from the switching control signal generation unit 9. The switching control signal input to the switching operation unit 2 is the same signal as the switching control signal input to the switching operation unit 1.

[0083] The switching operation unit 2 generates a second angle detection signal V S Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 2 inverts and outputs the second angle detection signal V S is the frequency ω R The signal inverted by the switching operation part is output signal V SS On the other hand, when the pair of angle detection signals are signals containing a carrier wave component, the switching operation unit 2 outputs the second angle detection signal V S is the frequency ω R The switching operation part output signal V SS Output as

[0084] Each of the switching operation unit 1 and the switching operation unit 2 is configured by an analog circuit.

[0085] The phase lock unit 7 includes a signal processing unit 71, a digital signal conversion unit 72, a control law 73, an integrating unit 74, a subtracting unit 75, and a signal conversion unit 76.

[0086] The signal processing unit 71 includes a multiplication unit 711 , a multiplication unit 712 , and a subtraction unit 713 .

[0087] The multiplication unit 711 receives the switching operation unit output signal V output from the switching operation unit 1. CS is input, and a signal converter output signal cosω, which will be described later, is output from the signal converter 76. L t is input to the multiplier 711. The multiplier 711 multiplies the switching operation unit output signal V CS and the signal conversion unit output signal cosω L t are multiplied together, and the multiplied signal is output to subtraction section 713.

[0088] The multiplication unit 712 receives the switching operation unit output signal V output from the switching operation unit 2. SS is input, and a signal converter output signal sinω, which will be described later, is output from the signal converter 76. Lt is input to the multiplier 712. The multiplier 712 multiplies the switching operation unit output signal V SS and the signal conversion unit output signal sinω L t are multiplied together, and the multiplied signal is output to subtraction section 713.

[0089] The subtractor 713 subtracts the switching operation unit output signal V CS and the signal conversion unit output signal cosω L The signals obtained by multiplying t are the switching operation unit output signal V SS and the signal conversion unit output signal sinω L The subtractor 713 subtracts t from the signals obtained by multiplying the two signals together, and outputs the signal obtained by the subtraction as a control deviation signal ε.

[0090] The control deviation signal ε output from the subtraction unit 713 is input to the digital signal conversion unit 72. The digital signal conversion unit 72 converts the control deviation signal ε from an analog signal to a digital signal. The digital signal conversion unit 72 outputs the converted control deviation signal y.

[0091] The converted control deviation signal y is input to the control law 73. The control law 73 is configured as a filter circuit that amplifies the control deviation signal y with a predetermined transfer characteristic such as PI compensation, and outputs a feedback control signal for performing negative feedback control so that the control deviation signal y converges to a constant value.

[0092] The feedback control signal output from the control law 73 is input to the integrator 74. The integrator 74 integrates the feedback control signal and outputs the calculated value as digital angle data φ.

[0093] The subtraction unit 75 receives a reference signal ω R The subtractor 75 receives the reference signal ω and the digital angle data φ output from the integrator 74. R The digital angle data φ is subtracted from t, and the subtracted value ω is obtained. L Outputs t.

[0094] The signal conversion unit 76 receives the calculated value ωL The signal conversion unit 76 receives the calculated value ω L Using t, the signal converter output signal cosω L t and signal converter output signal sinω L The signal converter 76 generates the signal converter output signal cosω L t and signal converter output signal sinω L Outputs t.

[0095] The reference signal generating unit 8 generates a reference signal ω R Generate a reference signal ω R t is the frequency ω R The polarity changes.

[0096] The switching control signal generating unit 9 receives the reference signal ω R When the pair of angle detection signals does not contain a carrier wave component, the switching control signal generator 9 outputs the reference signal ω R When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching control signal is output as a signal with a constant polarity. R The polarity changes when the pair of angle detection signals includes a carrier wave component, and the polarity becomes constant.

[0097] Next, a pair of angle detection signals output from the angle detection device are detected at a frequency ω R The operation of the angle detection signal processing device will be described below when the angle detection device is a phase modulation type angle detection device. When the angle detection device is a phase modulation type angle detection device, a pair of angle detection signals output from the angle detection device are expressed as K×E×cos(ω R t-θ) and K×E×sin(ω R t-θ), where K is the transformation ratio and E is a constant. When the angle detection device is an amplitude modulation type angle detection device, the pair of angle detection signals output from the angle detection device is expressed as K×E×sinω R t×sinθ and K×E×sinωR It is t×cosθ.

[0098] When the pair of angle detection signals are signals containing a carrier wave component, the switching control signal generation unit 9 outputs a switching control signal with a constant polarity. Therefore, when the pair of angle detection signals are signals containing a carrier wave component, switching control signals with a constant polarity are input to the switching operation units 1 and 2.

[0099] When the pair of angle detection devices are phase modulation type angle detection devices, the control deviation signal ε is calculated by the following equation (13), and when the pair of angle detection devices are amplitude modulation type angle detection devices, the control deviation signal ε is calculated by the following equation (14).

[0100] ε=K×E×cos(ω R t-θ)×sinω L tK×E×sin(ω R t-θ)×cosω L t =K×E×sin(ω L t-ω R t+θ) =K×E×sin(θ-φ) (13) ε=K×E×sinω R t×sinθ×sinω L t-sinω R t×cosθ×cosω L t =K×E×1 / 2×{sin(θ-φ)-sin(2ω R t+θ-φ)} (14)

[0101] In the above equation (13), negative feedback control operates so that the control deviation signal ε becomes zero, so that θ=φ, that is, φ follows θ. As a result, the angle detection signal processing device outputs digital angle data φ.

[0102] In the above equation (14), the second term is a high-frequency component with a frequency of 2ω0, which is attenuated by the filter effect of the control law 73 and the integrator 74. As a result, in the above equation (14), negative feedback control operates so that the control deviation signal ε becomes zero, so that θ = φ, i.e., φ follows θ. As a result, the angle detection signal processing device outputs digital angle data φ.

[0103] Next, the operation of the angle detection signal processing device when the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component will be described. The pair of angle detection signals that do not contain a carrier wave component are assumed to be cos θ and sin θ.

[0104] When the angle detection signal is a signal that does not include a carrier wave component, the switching control signal generator 9 generates a signal having a frequency ω R The switching control signal has a frequency ω R If the frequency matches the frequency of the angle detection signal V, there are no restrictions on the H / L duty and phase. Therefore, the H / L duty is set to 50:50 and the phase is set to 0. In this case, the switching operation unit 1 C at frequency ω R The square wave of is multiplied, and the angle detection signal V S at frequency ω R is multiplied by a square wave.

[0105] frequency ω R The square wave of the switching operation unit output signal V CS is calculated by the following equation (15), and the switching operation unit output signal V SS is calculated by the following equation (16).

[0106] V CS =cosθ×4 / π×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···} =4 / π×cosθ×sinωR t+4 / 3π×cosθ×sin3ω R t+4 / 5π×cosθ×sin5ω R t+··· (15) V SS =sinθ×4 / π×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···} =4 / π×sinθ×sinω R t+4 / 3π×sinθ×sin3ω R t+4 / 5π×sinθ×sin5ω R t+··· (16)

[0107] Using the above equations (15) and (16), the control deviation signal ε is calculated by the following equation (17).

[0108] ε=V SS ×sinω L tV CS ×cosω L t =4 / π×sinθ×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···}×sinω L t-4 / π×cosθ×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···}×cosω L t =2 / π×{sin(θ-φ)-sin(2ω R t+θ-φ)}-1 / 3×sin(2ω R t-θ+φ)-1 / 5×sin(4ω R t-θ+φ)-1 / 5×sin(6ω R t+θ-φ)···} (17)

[0109] In the above equation (17), the second and subsequent terms are the frequency 2ω RThese high frequency components are attenuated by the filter effect of the control law 73 and the integrator 74. As a result, in the above equation (17), negative feedback control operates so that the control deviation signal ε becomes zero, so that θ = φ, i.e., φ follows θ. As a result, the angle detection signal processing device outputs digital angle data φ.

[0110] Next, an angle detection signal processing device of a second comparative example will be described. FIG. 6 is a block diagram showing the angle detection signal processing device of the second comparative example. Unlike the angle detection signal processing device according to the third embodiment, the angle detection signal processing device of the second comparative example does not include a switching operation unit 1 and a switching operation unit 2. The other configurations of the angle detection signal processing device of the second comparative example are similar to the configurations of the angle detection signal processing device according to the third embodiment.

[0111] The operation of the angle detection signal processing device of the second comparative example when the pair of angle detection signals output from the angle detection device are signals including a carrier wave component is similar to the operation of the angle detection signal processing device according to the second embodiment.

[0112] When the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component, the angle detection signal processing device of the second comparative example calculates the control deviation signal ε by the following equation (18).

[0113] ε=sinθ×sinω L t-cosθ×cosω L t =-cos(θ-φ+ω R t) (18)

[0114] In the above equation (18), the control deviation signal ε has a frequency ω RThe control deviation signal ε is composed only of high-frequency components, and is attenuated by the filter effect of the control law 73 and the integrator 74. As a result, the control deviation signal ε remains constant regardless of θ. As a result, the phase lock unit 7 cannot perform negative feedback control so that θ = φ. In other words, in the angle detection signal processing device of the second comparative example, if the pair of angle detection signals does not contain a carrier wave component, the phase lock unit 7 cannot output phase angle data corresponding to the digital angle data φ. As a result, the angle detection signal processing device of the second comparative example cannot output the digital angle data φ.

[0115] On the other hand, in the angle detection signal processing device according to embodiment 3, the phase lock unit 7 can output the digital angle data φ regardless of whether the pair of angle detection signals contain a carrier wave component. As a result, the angle detection signal processing device according to embodiment 3 can output the digital angle data φ regardless of whether the pair of angle detection signals contain a carrier wave component.

[0116] As described above, the angle detection signal processing device according to the third embodiment includes the phase lock unit 7, and the switching operation units 1 and 2, which are provided on the input side of the phase lock unit 7 and to which the pair of angle detection signals are input. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching operation units 1 and 2 convert each of the pair of angle detection signals into a signal with a frequency ω R When the pair of angle detection signals are signals containing a carrier wave component, the switching operation unit 1 and the switching operation unit 2 invert the pair of angle detection signals at a frequency ω R According to this configuration, the angle detection signal processing device can output the digital angle data φ regardless of whether the pair of angle detection signals are signals including a carrier wave component or not.

[0117] In the angle detection signal processing device according to the third embodiment, a switching control signal is input to the switching operation unit 1 and the switching operation unit 2. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching control signal has a frequency ω R The polarity of the pair of angle detection signals changes with the frequency ω, and the polarity is kept constant when the pair of angle detection signals contain a carrier wave component. The switching operation unit 1 and the switching operation unit 2 invert and output the pair of angle detection signals in response to the change in polarity of the switching control signal. With this configuration, the switching operation unit 1 and the switching operation unit 2 can, with a simple configuration, in the case where the pair of angle detection signals do not contain a carrier wave component, respectively convert the pair of angle detection signals into signals with a frequency ω R can be used to invert and output.

[0118] In the angle detection signal processing device according to the third embodiment, the frequency ω R is a frequency that matches the reference frequency used in the phase lock unit 7. With this configuration, there is no need to provide a new signal generating unit for generating the switching control signal, which simplifies the configuration of the angle detection signal processing device.

[0119] In the angle detection signal processing device according to the third embodiment, the switching operation unit 1 and the switching operation unit 2 are configured as analog circuits. However, this configuration is not limiting. The switching operation unit 1 and the switching operation unit 2 may be configured as digital circuits. In this case, digital data processing of the pair of angle detection signals is performed before the pair of angle detection signals are input to the switching operation unit 1 and the switching operation unit 2. When the switching operation unit 1 and the switching operation unit 2 are configured as digital circuits, it is possible to suppress the superposition of an error signal on the pair of angle detection signals due to an imbalance in switching characteristics.

[0120] Embodiment 4 7 is a block diagram showing an angle detection signal processing device according to embodiment 4. In the angle detection signal processing device according to embodiment 4, the switching operation unit 1 is provided inside the phase lock unit .

[0121] The switching operation unit 1 receives the control deviation signal y output from the digital signal conversion unit 72. The switching operation unit 1 also receives the switching control signal output from the switching control signal generation unit 9. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching control signal has a frequency ω R The polarity changes when the pair of angle detection signals includes a carrier wave component, and the polarity is constant.

[0122] The switching operation unit 1 inverts and outputs the control deviation signal y in response to a change in polarity of the switching control signal. Specifically, when the pair of angle detection signals does not contain a carrier wave component, the switching operation unit 1 inverts and outputs the control deviation signal y at a frequency ω R The signal inverted by the switching operation part output signal ε S On the other hand, when the pair of angle detection signals contains a carrier wave component, the switching operation unit 1 outputs the control deviation signal y as a signal with a frequency ω R The switching operation part output signal ε S The switching operation unit output signal ε output from the switching operation unit 1 is S is input to the control law 73.

[0123] Other configurations of the angle detection signal processing device according to the fourth embodiment are the same as those of the angle detection signal processing device according to the third embodiment.

[0124] Next, a pair of angle detection signals output from the angle detection device are detected at a frequency ω R The operation of the angle detection signal processing device will be described below when the angle detection device is a phase modulation type angle detection device. When the angle detection device is a phase modulation type angle detection device, a pair of angle detection signals output from the angle detection device are expressed as K×E×cos(ωR t-θ) and K×E×sin(ω R t-θ), where K is the transformation ratio and E is a constant. When the angle detection device is an amplitude modulation type angle detection device, the pair of angle detection signals output from the angle detection device is expressed as K×E×sinω R t×sinθ and K×E×sinω R It is t×cosθ.

[0125] When the pair of angle detection signals contain a carrier wave component, the switching control signal generator 9 outputs a switching control signal with a constant polarity. Therefore, a switching control signal with a constant polarity is input to the switching operation unit 1.

[0126] When the pair of angle detection devices are phase modulation type angle detection devices, the switching operation unit output signal ε S is calculated by the following equation (19), and when the angle detection device is an amplitude modulation type angle detection device, the switching operation unit output signal ε S is calculated by the following equation (20).

[0127] ε S =K×E×cos(ω R t-θ)×sinω L tK×E×sin(ω R t-θ)×cosω L t =K×E×sin(ω L t-ω R t+θ) =K×E×sin(θ-φ) (19) ε S =K×E×sinω R t×sinθ×sinω L tK×E×sinω R t×cosθ×cosω L t =K×E×1 / 2×{sin(θ-φ)-sin(2ω R t+θ-φ)} (20)

[0128] In the above equation (19), the switching operation unit output signal εS Since negative feedback control works so that θ=φ, that is, φ follows θ, the angle detection signal processing device outputs digital angle data φ.

[0129] In the above equation (20), the second term is a high-frequency component of frequency 2ω0, which is attenuated by the filter effect of the control law 73 and the integrator 74. As a result, in the above equation (20), the switching action unit output signal ε S Since negative feedback control works so that θ=φ, that is, φ follows θ, the angle detection signal processing device outputs digital angle data φ.

[0130] Next, the operation of the angle detection signal processing device when the pair of angle detection signals output from the angle detection device are signals that do not contain a carrier wave component will be described. The pair of angle detection signals that do not contain a carrier wave component are assumed to be cos θ and sin θ.

[0131] When the angle detection signal is a signal that does not include a carrier wave component, the switching control signal generator 9 generates a signal having a frequency ω R The switching control signal has a frequency ω R There are no restrictions on the H / L duty and phase as long as the frequency matches the frequency ω. Therefore, the H / L duty is set to 50:50 and the phase is set to 0. In this case, the switching operation unit 1 applies a frequency ω R is multiplied by a square wave.

[0132] The square wave contains a fundamental frequency and odd-order high-frequency components. Therefore, the switching operation unit output signal ε S is calculated by the following equation (21).

[0133] ε S =y×4 / π×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···} =-cos(θ-φ+ωR t)×4 / π×{sinω R t+1 / 3×sin3ω R t+1 / 5×sin5ω R t+···} =2 / π×{sin(θ-φ)-sin(2ω R t+θ-φ)}-1 / 3×sin(2ω R t-θ+φ)-1 / 3×sin(4ω R t+θ-φ)-1 / 5×sin(4ω R t-θ+φ)-1 / 5×sin(6ω R t+θ-φ)···} (21)

[0134] In the above equation (21), the second and subsequent terms are the frequency 2ω R These high frequency components are attenuated by the filter effect of the control law 73 and the integrator 74. As a result, in the above equation (17), negative feedback control operates so that the control deviation signal ε becomes zero, so that θ = φ, i.e., φ follows θ. As a result, the angle detection signal processing device outputs digital angle data φ.

[0135] When the switching operation unit 1 is configured with an analog circuit, there is a possibility that an imbalance due to the switching operation may occur. However, in the angle detection processing device according to the fourth embodiment, the control deviation signal y is switched, so that an imbalance due to the switching operation does not occur in the phase-locked loop, and angle errors are suppressed.

[0136] As described above, the angle detection signal processing device according to the fourth embodiment is an angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device and performs digital angle conversion of the pair of angle detection signals using a phase-locked loop method. The angle detection signal processing device includes a phase lock unit 7 and a switching operation unit 1 that is provided inside the phase lock unit 7 and receives a control deviation signal y. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching operation unit 1 converts the control deviation signal y into a signal having a frequency ω RWhen the pair of angle detection signals contains a carrier wave component, the switching operation unit 1 inverts the control deviation signal y at a frequency ω R According to this configuration, the angle detection signal processing device can output the digital angle data φ regardless of whether the pair of angle detection signals are signals including a carrier wave component or not.

[0137] In the angle detection signal processing device according to the fourth embodiment, a switching control signal is input to the switching operation unit 1. When the pair of angle detection signals are signals that do not contain a carrier wave component, the switching control signal has a frequency ω R The polarity of the control deviation signal y changes with the frequency ω, and the polarity is constant when the pair of angle detection signals contain a carrier component. The switching operation unit 1 inverts and outputs the control deviation signal y in response to the change in polarity of the switching control signal. With this configuration, the switching operation unit 1 can, with a simple configuration, invert the control deviation signal y at a frequency ω when the pair of angle detection signals do not contain a carrier component. R can be used to invert and output.

[0138] Furthermore, in the angle detection signal processing device according to the fourth embodiment, the switching operation unit 1 is provided on the input side of the control law 73 in the phase lock unit 7. With this configuration, no imbalance due to switching operation occurs in the phase lock loop, and angle errors can be suppressed. As a result, the angle detection signal processing device can output highly accurate digital angle data φ.

[0139] Although the angle detection signal processing devices according to the preferred embodiments have been described above, the present invention is not limited to the angle detection signal processing devices according to the above-described embodiments. Various modifications and conversions can be made to the angle detection signal processing devices according to the above-described embodiments without departing from the scope of the claims. [Explanation of symbols]

[0140] 1 switching operation unit, 2 switching operation unit, 3 signal processing unit, 4 phase lock unit, 5 phase lock unit, 6 phase difference calculation unit, 7 phase lock unit, 8 reference signal generation unit, 9 switching control signal generation unit, 41 signal processing unit, 42 control law, 43 phase angle data generation unit, 51 signal processing unit, 52 control law, 53 phase angle data generation unit, 71 signal processing unit, 72 digital signal conversion unit, 73 control law, 74 integrator unit, 75 subtractor unit, 76 signal conversion unit, 411 multiplier unit, 412 multiplier unit, 413 adder unit, 414 signal generation unit, 431 signal generation unit, 432 counter, 511 multiplier unit, 512 multiplier unit, 513 adder unit, 514 signal generation unit, 531 signal generation unit, 532 counter, 711 multiplier unit, 712 multiplier unit, 713 Subtraction section.

Claims

1. An angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device, performs digital angle conversion of the pair of angle detection signals using a phase-locked loop method, and outputs digital angle data, A phase lock unit (4, 5, 7), a switching operation unit (1, 2) provided on the input side of the phase lock unit (4, 5, 7) and receiving the pair of angle detection signals; Equipped with The switching operation unit (1, 2) When the pair of angle detection signals are signals that do not contain a carrier wave component, the pair of angle detection signals are inverted at a preset frequency and output; an angle detection signal processing device that outputs each of the pair of angle detection signals at the predetermined frequency without inverting the signals when the pair of angle detection signals are signals including a carrier wave component;

2. A switching control signal is input to the switching operation unit (1, 2), the switching control signal changes polarity at the predetermined frequency when the pair of angle detection signals are signals that do not include a carrier wave component, and the switching control signal has a constant polarity when the pair of angle detection signals are signals that include a carrier wave component; 2. The angle detection signal processing device according to claim 1, wherein the switching operation unit (1, 2) inverts and outputs the pair of angle detection signals in response to a change in polarity of the switching control signal.

3. An angle detection signal processing device that receives a pair of angle detection signals output from an angle detection device, performs digital angle conversion of the pair of angle detection signals using a phase-locked loop method, and outputs digital angle data, A phase lock unit (4, 5, 7), a switching operation unit (1, 2) provided inside the phase lock unit (4, 5, 7) and receiving a control deviation signal; Equipped with The switching operation unit (1, 2) When the pair of angle detection signals are signals that do not contain a carrier wave component, the control deviation signal is inverted at a preset frequency and output. An angle detection signal processing device that outputs the control deviation signal at a preset frequency without inverting it when the pair of angle detection signals are signals containing a carrier wave component.

4. A switching control signal is input to the switching operation unit (1, 2), the switching control signal changes polarity at the predetermined frequency when the pair of angle detection signals are signals that do not include a carrier wave component, and the switching control signal has a constant polarity when the pair of angle detection signals are signals that include a carrier wave component; 4. The angle detection signal processing device according to claim 3, wherein the switching operation unit (1, 2) inverts and outputs the control deviation signal in response to a change in polarity of the switching control signal.

5. 5. The angle detection signal processing device according to claim 3, wherein the switching operation unit (1, 2) is provided on the input side of a control law (42, 52, 73) in the phase lock unit (4, 5, 7).

6. 5. The angle detection signal processing device according to claim 1, wherein the preset frequency is a frequency that coincides with a reference frequency used in the phase lock unit (4, 5, 7).

7. 5. The angle detection signal processing device according to claim 1, wherein the switching operation unit (1, 2) is configured by a digital circuit.

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