JPH0792178A - Phase/angular velocity detector for synchronous electric machine - Google Patents

Abstract

PURPOSE:To provide a highly reliable phase/angular velocity detector for synchronous electric machine which can detect abnormality of synchronous electric machine accurately. CONSTITUTION:The phase/angular velocity detector for synchronous electric machine comprises an synchronous electric machine 3, a SIN signal generator 9 and a COS signal generator 10 generating two-phase sine wave signals connected with the primary of the machine 3, an operating unit 5 for operating the phase difference between two signals from the machine 3 and a reference signal from a reference signal generator 4, a PI controller 6 for controlling a V/F converter 7 to nullify the phase difference, and a counter 8 for counting the output from the V/F converter 7 and delivering the output to the SIN and COS signal generators 9, 10. The phase/angular velocity detector further comprises an abnormality detector 14 for comparing the phase difference from the operating unit 5 with an abnormal level from a phase difference abnormality setter 15 and outputting an abnormal alarm signal, and an adder 11 and a differentiator 12 for adding the reference signal from the reference signal generator 4 and an output from the counter 8 and delivering the sum to a controller 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase / angular velocity detecting device for a synchronous electric machine for detecting the phase of a rotating object.

[0002]

2. Description of the Related Art As a phase detector for a rotating object, there is a synchro electric machine. The structure of the synchro electric machine is the same as that of a wound-type induction generator, and when a sine wave signal is input, it outputs a sine wave signal whose phase relationship is shifted depending on the phase of the rotating body. The phase / angular velocity of the rotating body can be detected by configuring a synchro output conversion circuit, that is, a PLL that detects a rotational position (phase) signal and a velocity signal based on the relationship. Further, due to the recent development of conversion technology, high-resolution detection is possible and plays a major role in the field of control of rotating bodies.

[0003]

The structure of the synchro electric machine has a brushless structure, and its reliability is relatively high.
Considering that the phase / angular velocity of the rotating body is an important control element in the control of the rotating body, it is very important to detect abnormality of the synchro electric machine. However, the output signal of the synchro electric machine is an analog sine wave signal of several kHz, and it is very difficult to detect an abnormality at that level. Therefore, an object of the present invention is to provide a phase / angular velocity detection device for a synchro electric machine.

[0004]

In order to achieve the above object, the present invention provides a signal on a synchro output conversion circuit for converting an excitation signal and a sine wave output signal of a synchro electric machine into a rotational position (phase) signal and a speed signal. Is detected and compared with an appropriate value of the position signal and speed signal obtained from the operating condition of the control system using the synchro electric machine, thereby detecting the abnormality of the synchro electric machine.

[0005]

An abnormality detecting device for monitoring not a sine wave output signal of a synchro electric machine which is difficult to detect an abnormality but a signal on a synchro output conversion circuit for converting the output signal into a rotation (phase) signal and a speed signal is constructed. As a result, it becomes possible to easily detect an abnormality in the synchronizing electric machine.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS There are various types of phase / angular velocity detecting devices for a synchro electric machine in which a synchro electric machine and a synchro output conversion circuit are combined, but in the embodiment of the present invention, a structure shown in FIG. The case of the target will be described. The phase / angular velocity detection device of the synchro electric machine shown in FIG. 1 will be briefly described.

In FIG. 1, ω _{ot is} the phase of the reference signal in the reference signal generator 4, θ is the actual phase of the rotor, and θ'is the detected phase of the rotor.

1 of the synchronizing electric machine 3 connected to the rotating body 1.
The SIN signal generator 9 and the COS signal generator 10 give a two-phase sine wave signal of SIN (ω _ot −θ ′) COS (ω _ot −θ ′) to the next side. Two signals of SIN (ω _ot −θ ′ + θ) COS (ω _ot −θ ′ + θ) are output to the secondary side.

The phase difference (SINω _ot CONω _ot ) output from the reference signal generator 4 and the above-mentioned two signals is input to the phase calculator 5 to perform the calculation represented by the equation (1). θ′−θ) is obtained.

[0010]

[Equation 1]

The PI controller 6 controls the V / F converter 7 so that this phase difference (θ'-θ) becomes 0, and the output of the V / F converter 7 is the phase signal accumulated by the counter 8. (Ω _ot
-.Theta. '), And the SIN signal generator 9 and the COS signal generator 10 generate the excitation signal on the primary side of the synchro electric machine described above.

As described above, the phase detector shown in FIG. 1 constitutes the PLL by the synchro electric machine and the synchro output converter, and when the PLL is settled, that is, (θ'-θ) = 0, the phase of the rotor becomes θ. An equal phase output θ ′ can be obtained, and the angular velocity ω can be obtained by differentiating the obtained phase output θ ′ by the differentiator 12.

The operation of the embodiment of the present invention will be described below. In this embodiment, the abnormality of the synchro electric machine is detected by monitoring the phase difference (θ'-θ) which is the control deviation in the synchro output conversion circuit.

As described above, when the synchronizing electric machine 3 is normal, the primary side excitation signal SIN (ω _ot −θ ′) COS (ω _ot −θ ′) is compared with SIN (ω _ot −θ ′ + θ) COS ( ω _ot −θ ′ + θ), the PLL is settled and the phase difference (θ′−θ)
Becomes almost 0 even if the error is added.

Therefore, the phase difference (θ'-θ) is input to the comparator 16 inside the abnormality detecting device 14 and compared with the abnormality level output from the phase difference abnormality setting device 15. The comparator 16 outputs an abnormality alarm signal when | phase difference |> | phase difference abnormality level setter output |

The phase difference (θ'-θ) obtained by the output signal of the synchro electric machine is compared with the abnormal alarm output level, and an abnormal alarm device for outputting an alarm in an abnormal state is constructed, which makes it difficult. It becomes possible to easily detect the abnormality.

In the above embodiment, the phase difference signal (θ'-
θ) is used, but the abnormality of the synchro electric machine is detected by using the angular velocity ω obtained by the phase / velocity detector in a specific operating state of the system using the synchro electric machine instead of the phase difference signal. It is also possible.

FIG. 2 shows an embodiment thereof.
In the stopped state of the system, in other words, in the stopped state of the rotating body, the detected angular velocity ω should be zero. The angular velocity ω detected there is input to the comparator 18 of the abnormality detection device 17, and the comparator 18 If does not hold, an abnormal signal is output. A logical product of the abnormal signal and the system stop signal is output as an abnormal signal of the synchronizing electric machine.

[0019]

In the synchro output conversion circuit for converting the output signal of the synchro electric machine into the phase signal and the speed signal, the abnormality of the synchro electric machine is detected by configuring the abnormality detecting device for monitoring the obtained phase signal and the speed signal. It became possible to detect easily.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a phase / angular velocity detection device of a synchronous electric machine showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a phase / angular velocity detection device of a synchronous electric machine showing a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotating body 2 ... Phase / angular velocity detection device 3 ... Synchro electric machine 4 ... Reference signal generator 5 ... Phase difference calculator 6 ... PI controller 7 ... V / F converter 8 ... Counter 9 ... SIN signal generator 10 ... COS signal generator 11 ... Adder 12 ... Differentiator 13 ... Control device 14, 17 ... Abnormality detection device 15 ... Phase difference abnormality setting device 16, 18 ... Comparator

Claims (2)

[Claims] 1. A phase / angular velocity detection device for a synchro electric machine, which detects a phase / angular velocity by configuring a synchro electric machine and a synchro output conversion circuit for converting a sine wave output signal thereof into a rotational position signal and a speed signal. A phase difference abnormality setting device that sets an abnormal level of the phase difference signal in the output conversion circuit, and a phase difference signal in the synchro output conversion circuit and the setting signal of the phase difference abnormality setting device are input and compared, and the phase difference signal is input. Is above the abnormality set level, the phase / angular velocity detection device of the synchro electric machine is configured with a comparator which judges that the synchro electric machine is abnormal and outputs an abnormality alarm. 2. A phase / angular velocity detecting device of a synchro electric machine for detecting a phase / angular velocity by configuring a synchro output converting circuit for converting a synchro electric machine and its sine wave output signal into a rotational position (phase) signal and a speed signal. , A comparator that inputs an angular velocity detected by the phase / angular velocity detection device of the synchro electric machine and outputs an abnormal signal when the angular velocity is not 0, and the abnormal signal and a control device that uses the phase / angular velocity detection device. A phase / angular velocity detection device for a synchro electric machine, which outputs an abnormality alarm for the synchro electric machine based on a logical product of system stop signals.