JPH0255839B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting state quantities of a rotating body.

Conventionally, state quantities of a rotating body such as a turbine or a compressor, such as the strain on the rotor blades that are attached to the rotor in the radial direction and perform energy conversion between the rotating shaft and the working fluid, and the pressure on the surface of the rotor blade, have been used. Alternatively, when measuring temperatures, etc. at various points on a rotating body, a slip ring or radio telemeter is used to extract signals from the rotating body to the outside. For example, FIG. 1 shows a configuration diagram of a state quantity detection device for a rotating body using a radio telemeter. Various state quantities obtained by a sensor 3 (for example, a strain gauge, a thermocouple, a pressure transducer, etc.) detecting state quantities on a rotating body are transmitted via a transmitter 20 to a transmitting antenna 21 to a receiving antenna 41 on a stationary side. sent to. In the figure, 4 is a battery for the transmitter, and 40 is a receiver. As described above, various state quantities on the rotating side are taken out to the external stationary side. External extraction of signals using a radiotelemeter has the advantage of not using the end of the rotating shaft and that transmission and reception can be performed without contact, but there is a limit to the frequency band of the carrier wave that can be used when transmitting state quantity signals. Furthermore, when transmitting multiple state quantity signals, it is necessary to provide carrier waves with a frequency interval of at least a certain degree to avoid interference, so in general, an interval of 2 MHz or more is required to avoid interference. For the reasons mentioned above, radio telemeters
The number of state quantity signals to be transmitted cannot be increased too much.
That is, there is a drawback that the number of channels is limited. Furthermore, there are also drawbacks such as the troublesome setting up of the transmitting and receiving antennas and the generation of noise during transmitting and receiving due to the influence of surrounding metal objects and magnetic fields.
Slip rings can extract more channel signals than radio telemeters, but because they use the end of the rotating shaft and use mercury or carbon brushes to send and receive signals between the rotating and stationary sides, noise is generated at the contact area. It has disadvantages such as being easy to clean and having a short lifespan.

On the other hand, recently, a detection device using an optical signal has appeared as a detection device that does not have these drawbacks.

That is, the detection device using this optical signal converts a signal detected on the rotating body side into an optical signal, and transmits this optical signal to the stationary side.

This method does not have the drawbacks mentioned above, but although it is possible to detect a momentary state quantity, it is not possible to detect a dynamic state quantity of a rotating body. It was hot.

The present invention was conceived with this in mind, and its purpose is to facilitate multi-channelization;
It is an object of the present invention to provide a device of this kind that is free from the possibility of noise generation due to the influence of magnetic fields and the like and is capable of detecting the dynamic state quantity of a rotating body.

That is, the present invention provides a counting storage section and an interface for counting and storing the output electrical signals of an element arranged on a stationary side and converting light into an electrical signal, and outputting data of the counting storage section to the interface. The output data is sent to a computer via the computer, and data processing is performed to rearrange the output data in chronological order, thereby reproducing and detecting the state quantity of the rotating body, thereby achieving the intended purpose.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A state quantity detection device for a rotating body using light, which is an embodiment of the present invention, will be described in detail below with reference to the drawings. FIG. 2 is a sectional view of a rotating machine showing the arrangement of an optical signal exchange device in a state quantity detection device for a rotating body using light according to an embodiment of the present invention.
A casing 2, a sensor 3 that detects the state quantity of the rotating body, a power supply section 4 that supplies power, an amplification bias circuit 15 for adding a signal amplification bias, and an electrical signal representing the state quantity obtained by the sensor 3 into an optical signal. an electro-optical conversion element 5′ for conversion, attached to the stationary side;
It consists of a photoelectric conversion element 6 which obtains an optical signal emitted from an electro-optic conversion element 5' and converts it into an electric signal. A state quantity detection sensor 3 installed on a rotary body 1 of a rotating device such as a turbine or a compressor for the purpose of measuring strain, pressure, or temperature is operated by electric power supplied from a power supply unit 4, and detects the detected value. The electrical signal of the state quantity is appropriately amplified and biased by the amplification bias circuit section 15 and sent to the electro-optical conversion element 5'. The electro-optic conversion element 5' constantly outputs light with an intensity proportional to the input electric signal current from the rotating body 1, and is placed on the stationary side, that is, on the casing, so as to face the light output direction of the electro-optic conversion element 5'. Light is sensed by one or more photoelectric conversion elements 6 arranged in the circumferential direction of the rotating body, and a current proportional to the intensity of the light is output. As an example, if the state quantity detection sensor is 1
We will describe the state quantity extraction and state quantity reproduction from a rotating body in the case of . A semiconductor laser is used as the electro-photoelectric conversion element. If the state quantity detected during one revolution of the rotating body does not change, one photoelectric conversion element is sufficient to be installed on the stationary side, but if the state quantity changes during one revolution, multiple photoelectric conversion elements are required. photoelectric conversion elements are required. FIG. 3 is an explanatory diagram showing signal extraction and output signals when the state quantity does not change during one rotation of the rotating body.
In FIG. 3, the casing side is omitted, and only the photoelectric conversion element 6 is depicted on the stationary side. Rotating body 1
is rotating at a constant angular velocity ω. At this time, the signal obtained by the state quantity detection sensor 3 is amplified and biased by the amplification bias circuit section 15 and sent to the semiconductor laser 5, and light having an intensity proportional to the signal current is emitted. Electro-optical conversion elements including semiconductor lasers emit light only in a certain direction, that is, when a forward current flows. Therefore, in order to operate even when the signal from the sensor is a reverse current and detect the state quantity, a bias is applied so that all the state quantity signals become a forward current. One photoelectric conversion element attached to the casing senses light only once during one rotation of the rotating body and outputs a current proportional to the intensity of the light. In FIG. 3, the output current and rotational pulses for outputting one pulse per rotation are plotted together with time on the horizontal axis. The output current obtained once per revolution is obtained as a pulse having a time interval of time t ₀ =2n/ω. Then, the state quantity of the rotating body can be detected from the state quantity-output current calibration value obtained in advance. FIG. 4 shows the optical output versus input current characteristics of the semiconductor laser. Although the optical output changes depending on the temperature, there is no problem if temperature correction is performed. If the semiconductor laser is to be used in a region where the relationship between the input current and the optical output is linear, the state quantity electric signal obtained by the sensor 3 is amplified by the amplification bias circuit section 15 and inputted to the semiconductor laser 5 after applying a bias. ,
By increasing the bias addition, a linear relationship between input current and optical output can be obtained. The example shown in Fig. 3, that is, the state quantity detection device for a rotating body using light according to the present invention, which uses only one photoelectric conversion element, can be used to measure static strain, temperature, and steady pressure in which the state quantities to be measured do not change over time. Suitable for etc. The fifth section describes the signal extraction and output signal when the state quantity changes during one rotation of the rotating body.
As shown in the figure. On the stationary side casing, a plurality of photoelectric conversion elements 6 are arranged on the rotating circumference so as to face the semiconductor laser 5 on the rotating body 1 so that the directions of light input and output coincide with each other. The light output direction of the semiconductor laser does not necessarily have to be parallel to the rotation axis. If they are not parallel, the light output direction changes over the entire circumference of the rotation, but it is sufficient to make the light receiving direction of the photoelectric conversion elements arranged at each position coincide with the light output direction. Fig. 5 shows an example using 10 photoelectric conversion elements, and Fig. 7 shows an arrangement diagram of the photoelectric conversion elements 6 arranged in the circumferential direction of the rotating body on the stationary side as seen from the axial direction. Shown as 6j. During one rotation of the semiconductor laser 5 mounted on the rotating body 1, the photoelectric conversion elements 6a to 6j each sense light once in this order, and the photoelectric conversion elements 6a to 6j in FIG.
7j pulse current is output. Since the state quantity is changing, the output current also changes in proportion to it.
At this time, the electro-optical conversion element operates and emits light only when a forward current flows, so even if the fluctuating component of alternating current is directly input to the electro-optical conversion element, it will not operate with a reverse current. Therefore, the amplification bias circuit section 15
By applying a bias to the light and inputting it to the semiconductor laser 5, the fluctuating component can be converted into light. 6th
The figure shows a block diagram of a circuit that converts the variable state quantity obtained by the sensor into a forward current that can be photoelectrically converted, and shows how the signal changes. The state quantity signal I obtained by the sensor 3 is amplified by an amplification section in the amplification bias circuit section 15 and becomes a signal. However, if power is applied to the semiconductor laser 5 in this state, there will be a reverse current, and in this case, if a negative current is used as a reverse current, no electro-optical conversion will occur in the region where the current is negative. Therefore, a bias section in the amplification bias circuit section 15 applies a bias, so that all the currents are forward currents and positive currents. By inputting this to the laser semiconductor 5 that performs electro-optical conversion, it is possible to transmit the fluctuating state quantity obtained by the sensor 3 as an optical signal. The pulse currents in FIG. 5 are arranged in time series and the vertices are connected to form a signal 8, which is the state quantity obtained by the sensor 3 on the rotating body 1. In this way, the present invention makes it possible to obtain state quantities of the rotating body that vary over time. Although the case where there is one measured state quantity has been described above, the present invention is similarly applicable to the case where there is a plurality of measured state quantities. For example, consider a case where there are three state quantities to be measured. The measured state quantity is 3
Therefore, three semiconductor lasers are required to convert each state quantity electrical signal into an optical signal, and each semiconductor laser is designated by symbols 5a, 5b, and 5c.
Expressed as Semiconductor lasers 5a to 5c on the casing side
The number of photoelectric conversion elements that are arranged in the circumferential direction of the rotating body in such a manner that they face each other so that the light input and output directions coincide with each other is 7, and they are designated by symbols 6a, 6b, 6c, 6c, Represented by 6d, 6e, 6f, and 6g. Each photoelectric conversion element senses a total of three optical outputs from the semiconductor lasers 5a, 5b, and 5c during one rotation of the rotating body, and outputs three current pulses. FIG. 7 shows current pulses output by receiving the optical outputs of the semiconductor lasers 5a, 5b, and 5c by the photoelectric conversion elements 6a to 6g. The output currents of the photoelectric conversion elements 6a to 6g are shown as 7a to 7g, the horizontal axis represents the passage of time, and the rotation pulse signal of one pulse per revolution is also shown. The data in Figure 8 includes three state quantity signals, but since they appear in the output of one photoelectric conversion element, the three state quantities are separated using the rotation pulse as a reference, and the signals are obtained from each sensor. can be the state quantity given. In FIG. 8, the current connected by the broken line from 7a to 7g is a series of state quantities obtained from the semiconductor laser 5a, and the rotating body is 1
After the rotation, the signals from the semiconductor laser 5a are output again from 7a to 7b, 7c, . . . . Currents connected by one-dot chain lines represent a series of state quantities obtained from the semiconductor laser 5b, and currents connected by two-dot chain lines represent a series of state quantities obtained from the semiconductor laser 5c.
Figure 9 shows the data obtained as shown in Figure 8 separated into each state quantity, arranged in chronological order, and connected in a connected manner. Signals 8a, 8b, and 8c correspond to the optical outputs of semiconductor lasers 5a, 5b, and 5c, respectively. These data are discretized because they are based on pulse signals obtained when a semiconductor laser passes through a photoelectric conversion element, but we would like to obtain data with high-frequency components of fluctuating state quantities or with increased connectivity. In this case, many photoelectric conversion elements may be used.
Data processing can be performed using a computer in order to organize the outputs of a plurality of photoelectric conversion elements and reproduce state quantities. FIG. 10 shows an overall configuration diagram of the system of the present invention including data processing by a computer. The state quantity of the rotating body obtained by the sensor 3 is detected by the semiconductor laser 5.
The signal is converted into an optical signal and transmitted to the photoelectric conversion element 6 on the stationary side. At this time, as described above, the number of semiconductor lasers and the number of photoelectric conversion elements do not need to be the same, and the number of photoelectric conversion elements is determined based on the relationship between the degree of variation of the state quantity to be measured, frequency, and the like. The photoelectric conversion element 6 senses the light output from the semiconductor laser 5 and outputs a current pulse. The counting storage section 9 reads the value of the current pulse and stores the value in the memory. The stored data is sent to the computer 11 via the interface 10, and the rotation pulse 11 generated by the rotation pulse generator 16 is used to calculate the rotation number and rotation speed in the pulse counting storage section 17, and based on the data. Computer processing is performed, and each state quantity obtained by the sensor 3 can be reproduced. Next, we will explain the data processing algorithm using a computer. Figure 11 shows five photoelectric conversion elements 6a to 6b attached to the stationary side.
FIG. 2 is a schematic diagram showing the relative positional relationship between the semiconductor laser 5a and two semiconductor lasers 5a and 5b that are mounted on a rotating body and rotate together with the rotating body. This rotating body is equipped with a rotational pulse generator (not shown), and the rotating body pulse generator generates one pulse every time the rotating body rotates once. FIG. 11 is a diagram showing, as an example, the position of the semiconductor laser at the moment when the rotation pulse is generated. At this moment, the semiconductor laser 5a
is at a position of -θ ₁ degree clockwise from the perpendicular V, and the rotating body is located at a -θ ₂ degree position from the perpendicular V. The rotating body rotates counterclockwise as shown by the arrow to the semiconductor lasers 5a and 5b. Suppose there is. The relative positional relationship of the photoelectric conversion elements arranged on the stationary side is expressed by an angle from δ ₁ to δ ₅ . Figure 12 shows the main contents of the computer processing. When measurement begins, data recording begins using the first rotation pulse as a trigger. FIG. 11 shows the positions of the semiconductor lasers 5a, 5b at this time. Since the rotating body rotates counterclockwise at an angular velocity ω, the optical output from the semiconductor laser 5a is transferred to the photoelectric conversion elements 6a, 6b, 6c. , 6d, and 6e are sensed in this order. Further, the output of the semiconductor laser 5b is sensed during one rotation in the order of 6d, 6e, 6a, 6b, and 6c. Each photoelectric conversion element senses light twice during one rotation of the rotating body and performs photoelectric conversion. Then, as the rotation continues, the count storage unit generates a sequence of current outputs A(), B(), C.
(), D(), E() (=1, 2, 3...) are formed. These numerical sequences correspond to the outputs of the photoelectric conversion elements 6a to 6e, respectively. In parallel with this, data recording started and the first
The pulse count storage unit in FIG. 0 counts and stores the inter-pulse time of one pulse per revolution, and a sequence of required times per revolution T( ) (=1, 2, 3, . . . ) is formed. In each of the numerical sequences A() to E(), semiconductor lasers 5a and 5b and two data are arranged alternately, so they are separated and further A() to E() are arranged.
By rearranging (), the semiconductor laser 5
It is necessary to restore the continuous data of each of a and 5b, that is, the original state quantity. Among the data obtained by the photoelectric conversion elements 6a to 6c after the start of recording, the odd-numbered data are from the semiconductor laser 5a, and the even-numbered data are from the semiconductor laser 5b. The opposite is true for the data of the photoelectric conversion elements 6d and 6e. That is, among the sequence A() to E() formed by photoelectric conversion element output count storage, {A-(2J-1), B(2J-1), C(2J-1)
，
The sequence formed by D(2J), E(2J)} (J=1, 2, 3, ...) is the output of the semiconductor laser 5a rearranged in time series, and {D(2J− 1),
E (2J-1), A (2J), B (2J), C (2J)} (J=
1,
The sequence of numbers (2, 3, . . . ) is the output of the semiconductor laser 5b rearranged in time series. In order to reproduce the state quantity of the rotating body using the number sequence formed above, it is necessary to know the data, that is, the time interval between the components of the number sequence. For example, the time interval T _AB () between the sequence A() and B() can be calculated by using the photoelectric conversion element arrangement interval angle δ ₁ and further using the time sequence T() between rotational pulses, T _AB ()=T() It can be found by ×δ ₁ /360. Since T() is calculated for each rotation,
Even if the rotation speed changes, there will be no error in T _AB . Between T() and rotational angular velocity ω, ω=1/
There is a relationship of 2πT(). If the above-described number sequence formation processing is performed by a computer, it becomes possible to automatically obtain a plurality of state quantities obtained by the sensor without human intervention. Note that in Figures 10 to 12, 2
Although we have described the case where state quantities are determined, any number of state quantities can be detected by similar processing.
As an example, the state quantity signal is converted into an optical signal by a semiconductor laser, the state quantity signal is extracted as an optical signal from the rotating body to the stationary side, and the optical signal is sensed by a photoelectric conversion element provided on the stationary side. The above description has described a device for detecting the state quantity of a rotating body using light, which converts the signal into an electrical signal, performs signal processing using a computer, and obtains the state quantity of the rotating body.Next, other embodiments of the present invention will be described. .

In FIG. 2, the state quantity signal of the rotating body 1 detected by the sensor 3 is appropriately amplified and biased and sent to the electro-optical conversion element 5', where the electric signal is converted into an optical signal and sent to the stationary side. On the stationary side, a photoelectric conversion element 6 attached to the casing receives an optical signal and converts it into an electrical signal.As shown in FIG. It is attached to the casing and guides the optical signal emitted by the electro-optical conversion element 5' to an arbitrary position.
It is also possible to provide a photoelectric conversion element 6 at the other end to convert it into an electrical signal. By providing a spherical or cylindrical lens 14 as shown in FIG. 14 at the tip of the optical fiber shown in FIG. 13, the light emitted by the electro-optical conversion element 5' can be efficiently guided to the optical fiber 13. . Although not shown in FIG. 14, a similar lens is also used at the tip of the optical fiber 13 facing the photoelectric conversion element 6 to improve the efficiency of the light passing through the optical fiber 13. It is also possible to input the signal to a photoelectric conversion element. Furthermore, although a semiconductor laser is used as the electro-optical conversion element in the embodiment, it is also possible to use a light emitting diode.

As described above, according to the present invention, the output data of the photoelectric conversion element is rearranged in time series to reproduce and detect the state quantity of the rotating body, so the movement of the rotating body can be detected without the risk of noise generation. state quantities can be detected.

[Brief explanation of the drawing]

Fig. 1 is a simple configuration diagram showing a conventional radiotelemeter system, Fig. 2 is a partial sectional view of a rotating machine showing a situation in which a state quantity detection device for a rotating body, which is an embodiment of the present invention, is installed. The figure is an explanatory diagram showing the steady state quantity detection situation of the state quantity detection device of the rotating body shown in Fig. 2, Fig. 4 is a characteristic diagram showing the characteristics of the semiconductor laser, and Fig. 5 is a variation in the embodiment of the present invention. An explanatory diagram showing the state quantity detection situation, Fig. 6 is a schematic diagram illustrating a bias circuit that operates the electro-optical conversion element, and Fig. 7 is a diagram illustrating a bias circuit that operates the electro-optical conversion element. FIG. 8 is an explanatory diagram showing the state of output signals from seven photoelectric conversion elements when detecting three state quantities in FIG. 5, and FIG. 10 is an explanatory diagram showing the separation of the signals obtained in the figure and reproducing the original three state quantities, FIG. Figure 12 is a schematic diagram showing the arrangement of a semiconductor laser and a photoelectric conversion element to explain data processing by a computer, and an explanatory diagram showing the calculation processing procedure and contents. Figure 13 is an optical fiber between the semiconductor laser and the photoelectric conversion element. FIG. 14 is a partial diagram showing a transmitting part in a state quantity detection device for a rotating body which is another embodiment of the present invention using the present invention, and FIG. It is a partial diagram showing an example of. 3...Sensor, 4...Power supply unit, 5...Semiconductor laser, 5'...Electro-optical conversion element, 16...Rotary pulse generator, 17...Pulse counting storage unit, 6...
Photoelectric conversion element, 13... optical fiber, 14... lens, 15... amplification bias circuit section.

Claims (1)

[Claims] 1. A sensor for detecting a state quantity of rotation, a device for converting the state quantity into an electrical signal based on a detection signal from the sensor, and a device for converting the electrical signal into an electrical signal on the rotation side of the rotating body. It is equipped with at least one electro-optical conversion element that converts into a signal, a power supply section that supplies power, and an amplification bias circuit section that amplifies the electrical signal and applies a bias. At least one photoelectric conversion element is arranged along the circumferential direction so as to face each other so as to coincide with the input/output direction, and the state quantity of the rotating body is determined by converting the optical signal output from the electro-optical conversion element into an electric signal. In the state quantity detection device of a rotating body, a count storage unit and an interface are provided on the stationary side to count and store electrical signals output from the photoelectric conversion element, and the output data of the count storage unit memory is transferred to the interface. 1. An apparatus for detecting the state quantity of a rotating body, characterized in that the state quantity of the rotating body is reproduced and detected by sending the output data to a computer via a computer, and performing data processing to rearrange the output data in time series. 2. At least one optical fiber is arranged on the stationary side in the circumferential direction of the rotating body so that one end thereof faces the light output direction of the electro-optic conversion element, and the other end of each optical fiber is provided with a photo-electric conversion element, 2. The state quantity detection device for a rotating body according to claim 1, wherein the state quantity of the rotating body is detected by the output electric signal of the photoelectric conversion element. 3. The state quantity detection device for a rotating body according to claim 2, characterized in that a condenser lens is attached to the tip of the optical fiber facing the electro-optical conversion element or the photoelectric conversion element. 4. The state quantity detection device for a rotating body according to claim 1, wherein the electro-optical conversion element is a semiconductor laser. 5. The state quantity detection device for a rotating body according to claim 1, wherein the electro-optical conversion element is a light emitting diode. 6. The state quantity detection device for a rotating body according to claim 1, wherein the rotating body is a turbine. 7. A patent claim characterized in that the state quantity detected by the sensor is vibration of a turbine rotor blade, and a plurality of photoelectric conversion elements are installed that receive light emitted by an electro-optic conversion element and convert it into an electrical signal. The state quantity detection device for a rotating body according to scope 7.