JPH04145899A - Brushless synchronous machine - Google Patents

Abstract

PURPOSE:To prevent the occurrence of delay time and a decline in signal transmitting efficiency by providing a plurality of annular light receiving sections for receiving optical signals emitted front light emitting sections opposite to the light emitting sections on a rotating shaft and controlling a rectifier by using the optical signals received by the annular light receiving sections. CONSTITUTION:A controller 5 makes a six-phase firing signal for controlling a rectifier 3 to be generated front the voltage signal of a synchronous generator 1 inputted through a voltage transformer A for instruments and the armature voltage of an AC exciter 2 inputted through a rotary transformer 7. The firing signal is transmitted to a rotor through a light emitting section 61 after the signal is converted into an optical signal by means of an optical signal transmitting mechanism 6A. The optical signal received by the light receiving section 6 of the rotor is converted into an electric signal by means of an O/E converting section 8. Upon receiving the firing pulse, a six-phase thyristor constituting the rectifier 3 is fired and the output of the armature of the AC exciter 2 is controlled and rectified. The controlled and rectified voltage outputted from the armature of the exciter 2 is supplied to the field winding 1A of the synchronous generator 1 and the output voltage of the generator 1 is controlled.

Description

Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to a flangeless synchronous machine with improved response characteristics.

(Prior Art) As is well known, in order to operate a synchronous machine, it is necessary to provide field magnetic flux by some means. Therefore, with the exception of small-capacity permanent magnet generators (hereinafter referred to as PMG), it has become common for synchronous machines to have a field winding, through which direct current is passed to generate field magnetic flux.

Generally, a synchronous machine has a rotor provided with a field winding and a stator used as an armature. Slip rings and brushes are used in synchronous machines to externally supply direct current to the field windings on the rotor. Due to their structure, these slip rings and brushes suffer from unavoidable wear and require frequent maintenance and inspection. Eliminating these slip links and brushes was a major challenge in the development of synchronous machines, but a long time has passed since this problem was solved and brushless synchronous machines were realized.

This type of brushless synchronous machine will be briefly explained using an example shown in FIG.

The synchronous generator 1 is of a rotating field type, and its field winding 3A
is provided on the rotor. The AC exciter 2 is of a rotating armature type, and its field winding 2A is provided on the stator side. The rectifier 3 is composed of a silicon rectifying element or the like and is provided on the rotor. The armature output voltage of the AC exciter 2 on the rotor side is rectified by a rectifier 3 provided on the rotor side, and the field winding I of the synchronous generator 1 also on the rotor side.
A is supplied as a direct current.

Therefore, to control the field current of the synchronous generator 1, the armature output voltage of the AC exciter 2 is controlled by controlling the current applied to the field winding 2A of the AC exciter 2 provided on the stator side. This can be done by doing this. The control device 5.5-1 is for this purpose, and the control device 5 outputs a control signal to control the control device 5-1.

The control device 5-1 includes a thyristor rectifier, controls the phase of the voltage generated by the PMG/I based on the control signal from the control device 5, and supplies the output voltage to the field winding 2A. P
MG4 is a power supply for the control device 5.5-1, and 4A is a permanent magnet for creating the field magnetic flux. Further, 5A is an instrument voltage transformer. Note that the part surrounded by the broken line in this figure is the part on the rotor side.

By the way, since this brushless synchronous generator 1 controls its field current via the AC exciter 2, the response is slower than that of an excitation system that directly controls the field current.

There are two methods to solve this response delay. One of them is to improve the response of the AC exciter 2. Another is to make the rectifier 3 controllable and to control this rectifier 3 by non-contact means. The latter is generally referred to as thyristor brushless because the ones that have been realized so far use a thyristor for the rectifier 3. Thyristor brushless is the only synchronous machine that does not require brushes or slip rings, which pose problems for maintenance and inspection, and can achieve high-speed response.

Typical conventional configuration example of thyristor/brushless is shown in the fifth section.
As shown in FIG. Figure 5 shows the thyristor rectifier 3
In this method, an ignition signal for controlling the motor is transmitted by a rotary transformer 6B. Here, the control device 4-1 outputs a control signal to the control device 4-2 in order to control the voltage supplied to the field winding 2. Further, the control device 4-2 phase rectifies the output voltage of the PH 10 based on the control signal and supplies the output voltage to the field winding. In FIG. 6, an AC control signal is transmitted to the rotor side by a rotary transformer 6C, and the ignition signal of the thyristor rectifier 3 is transmitted to a control device 5-2 provided on the rotor side.
Nii.

It is generated by

(Problems to be Solved by the Invention) Although it has been a long time since the thyristor brushless synchronous machine, which can be called an epoch-making synchronous machine, was developed, only a synchronous machine with an extremely small capacity has been realized.

The reason for this is that with the configuration shown in Figure 5, it is not easy to produce a rotating pulse transformer that can efficiently transmit steep rising pulses and that has a shape that can be used in thyristor/brushless synchronous machines. . For this reason, it is difficult to increase the transmission efficiency of the firing signal of the thyristor, and it is impossible to realize a large-capacity machine that requires the use of large thyristor elements in parallel.

In addition, in the configuration shown in Figure 6, there are many devices that must be installed on the rotor side, and if particularly sophisticated control is required, these devices will become larger and more numerous. It was difficult to apply it to the required synchronous machine.

In addition, an invention has been proposed that attempts to solve the difficulty of increasing capacity by using a light-igniting thyristor and giving the thyristor's firing signal as an optical signal (Japanese Patent Laid-Open No. 56-112
'11OO), but this does not disclose details about specific optical signal transmission.

Therefore, in order to solve these problems, it is an object of the present invention to provide a brushless synchronous machine with improved response characteristics suitable for increasing capacity.

[Structure of the Invention] (Means for Solving the Problems) Control signals from a control device provided in the stator section of a brushless synchronous machine are provided in the stator section in correspondence with the number of phases of the field winding of the synchronous machine. A plurality of light emitting parts are used to transmit the light signal to the rotor part as an optical signal. A plurality of annular light receiving sections provided on the rotating shaft to face the light emitting sections receive optical signals from the light emitting sections. The rectifier can be controlled by the optical signals received by these annular light receiving sections, and this control output voltage is supplied to the rotor winding of the synchronous machine.

(Function) By providing the control device on the stator side, which has no restrictions on external shape or weight, it is possible to easily generate a very strong signal to be applied to the control rectifier. Furthermore, since signals are transmitted to the rotor side using optical signals, there are no problems caused by time delays or low signal transmission efficiency. Therefore, a brushless synchronous machine with large capacity and high speed response can be realized.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the brushless synchronous machine of the present invention.

In FIG. 1, parts having the same functions and purposes as conventional brushless or thyristor brushless synchronous machines are indicated by the same reference numerals even if the means for realizing them is different.

Further, the functional parts that are not particularly different from those of the conventional thyristor brushless synchronous machine have been explained previously, so the description thereof will be omitted.

The control device 4-1.4-2 is a control device for controlling the excitation of the AC excitation w1.2 to keep the armature voltage of the AC exciter 2 substantially constant. The signal transmission section 7 is for transmitting the armature voltage of the AC exciter 2 to the stator side, and conventionally used a rotating transformer.

Since this does not require particularly fast response, a method of converting into an optical signal and transmitting it is not adopted, and a rotary transformer is used in this embodiment as in the conventional case.
, .11 The rectifier 3 is a three-phase equalized-bridge connected rectifier composed of conventional electrically ignited thyristor rectifying elements. The 0/E conversion section 8 converts the optical signal transmitted to the rotor side by the light emitting section 61 of the optical signal transmission mechanism 6A into an electrical signal, and amplifies it into a pulse signal necessary to fire the thyrisk element. be.

The control signal supplied to the light emitting section 61 of the optical signal transmission mechanism 6A is generated by the control device 5 provided in an appropriate location (for example, a control room) on the stator side.

FIG. 2 shows an embodiment of the optical signal transmission mechanism 6A provided in the brushless synchronous machine of the present invention, and FIG. The mounting of the light receiving section 62) indicates the positional relationship.

In this FIG. 2 (A), 1x is the axis of the rotor,
The black areas indicate the positions of the light-emitting surface of the light-emitting section and the light-receiving surface of the light-receiving section, respectively. In this embodiment, since a three-phase balanced bridge connection rectifier is used, six-phase signals are required, and correspondingly, the light emitting section 61 and the light receiving section 62 for the required number of phases are used.
has been established. The light emitting portions 61 do not need to be assembled in one place as a whole, and may be distributed and attached in the circumferential direction at positions facing the light receiving surfaces of the corresponding phases.

FIG. 2(B) is an external view showing the detailed configuration of one phase of the light emitting section 61. Here, 61-1 is an optical cable, 61-
Reference numeral 2 indicates a light distributor, and reference numeral 61-3 indicates a light emitting surface section. FIG. 2(C) is a surface view of the light emitting portion 61 taken from the direction of the arrow in FIG. 2(B).

FIG. 2(D) is an external view showing a partially detailed configuration of the light receiving section 62. As shown in FIG. Moreover, FIG. 2(E) is a surface view of the light receiving part 62 from the direction of the arrow in FIG. 2(D). Here, 621 indicates a unit photoreceptor that constitutes a light-receiving surface, and 62-IA indicates an optical fiber, one side of each of which is a plain surface that constitutes a light-receiving surface, and the opposite side is a one-terminal optical connector 62-2.
are gathering. In addition, 62-3 is an optical cable, 62-
4 indicates a multi-terminal optical connector.

For one phase of the light receiving section 62, a plurality of unit photoreceptors 62 to 1 are used to form an annular light receiving surface with a sufficient width.

Then, connect these to the optical connector 52-2 and the optical cable 6.
2-3, and is configured to be taken out from one of the multi-terminal optical connectors 62-4.

Further, the annular light-receiving surface does not necessarily need to have light-receiving ability all around. The reason is that the period when the ignition signal is not present (
This period differs for each phase), and this period is determined in the circumferential direction of the rotating body based on the number of poles of the AC exciter 2, the position of each phase armature winding, and the positional relationship of the light emitting part 61. This is because it can be converted to the position of

For example, if the number of poles of the AC exciter 2 is two, the area where light receiving ability is unnecessary will appear at one location on the circumference, and if the reactance of the AC exciter 2 is ignored, the size will be 180 degrees. . In this way, even considering that the phase of the generated voltage changes due to the effect of reactance, light receiving ability is not required over a fairly wide range. This area where light receiving ability is not required is divided into 1/2 of the number of poles of the AC exciter 2, and if reactance is ignored, the total is 180 degrees in either case. However, considering the reactance of the AC exciter 2, if the number of poles is large, the area where each light-receiving ability is not required becomes very narrow.

Further, the light-receiving surface in this embodiment is an aggregate of a microscopic light-receiving surface (hereinafter referred to as a photosensitive element surface) and a microscopic light-receiving non-receiving surface (hereinafter referred to as a photosensitive element surface) when viewed microscopically.

Therefore, in any corresponding positional relationship between the light emitting surface and the light receiving surface that change from the open side when the rotor of the synchronous generator 1 is rotating, the effective light emitting surface and the number of photosensitive element surfaces that can transmit a sufficient amount of light are Must be facing each other. For this reason, the structure is such that the light emitting surface is widened. One light emitting surface section 61-3
If the amount of transmitted light is insufficient, the light emitting surface portion 6
Just add 1-3. 1 phase optical cable 61
If the amount of light is likely to be insufficient for distribution from one optical fiber, a plurality of optical cables 61-1 may be used for one optical fiber.

Furthermore, in the configuration of this optical signal transmission section, it is necessary to fully consider that the relative position of the stator section and the rotor section varies greatly in the axial direction depending on the operating state. The width of the annular light-receiving surface could be made quite narrow if only the machining accuracy tolerance and light transmission efficiency were considered, but it is made wider to take into account changes in position in the axial direction. If the width of the unit photoreceptors 62-1 alone is insufficient, the necessary width can be secured by arranging a plurality of unit photoreceptors 62-1 in the axial direction as well.

Conversely, the width of the annular light-receiving surface may be minimized by increasing the axial width of the light-emitting surface portion 61-3.

In this case, it is necessary to ensure sufficient intervals between the annular light receiving surfaces of each phase so that the light emitting section and the light receiving section of different phases do not face each other due to axial movement of the annular light receiving surfaces.

With the above configuration, when the rotor of the synchronous generator 1 is driven and rotated by the prime mover (not shown), the PMG 4 generates a voltage. The control device 44.4- uses this PMG4 voltage as a power source.
2 provides excitation to the field winding 2A of the AC exciter 2. Thereby, the armature voltage of the AC exciter 2 is controlled to be substantially constant. The control device 5 converts the voltage signal of the synchronous generator 1 input via the instrument voltage transformer 5A and the armature voltage of the AC exciter 2 manually input via the rotary transformer 7 into the rectifier 3.
Generates a 6-phase ignition signal to control the This ignition signal is converted into an optical signal by the optical signal transmission mechanism 6A and transmitted from the light emitting section 61 to the rotor. The optical signal received by the light receiving section 62 of the rotor is converted into an electric signal (ignition pulse) by the O/E converting section 8. Next, in response to this firing pulse, the six-phase thyristor constituting the rectifier 3 is fired, and the armature output of the AC exciter 2 is controlled and rectified. The control rectified voltage of the armature output of this AC exciter 2 is applied to the field winding I of the synchronous generator 1.
The output voltage of the synchronous generator 1 is controlled by supplying A & .

Here, the detailed operation of the optical signal transmission mechanism 6A is as follows. The optical signals sent to each customer through the optical cables 61-1 are distributed to a plurality of optical cables 61-1 by the optical distributor 61-2 as shown in FIG. Light is emitted from the light emitting portion 61-3 at the tip of the light emitting device 1. In other words, it becomes a light emitting source with a relatively large area. This light is transmitted to the light-receiving surface 6 of the light-receiving section 62, which has a large area like the light emitting source.
The light is received at 2-1.

All of the optical signals received on this wide surface are collected by the multi-terminal optical connector 62-4. Therefore, optical signals can be transmitted from the stator side to the rotor side without being affected by changes in the relative positions of the light emitting section 61 and the light receiving section 62.

As described above, according to this embodiment, a brushless synchronous machine that does not require slip rings or brushes and directly controls the field voltage of the synchronous machine can be realized. Moreover, the control signal transmitted from the stator side to the rotor side of a brushless synchronous machine is a signal that can be generated with a simple circuit configuration. Unlike coupling (rotary transformer, etc.), the rise of the pulse signal does not slow down. In addition, in this embodiment, the 0/E converter 8
Although it must be mounted on the rotor, it simply converts the transmitted optical signal into an electrical signal, making it easy to produce a strong and compact device with simple circuits and parts.

Furthermore, since the control signal is generated by a control device installed in the stationary part, the technology used in the latest stationary exciter can be easily applied, and the high-class control required for large-capacity machines can be achieved.

One embodiment of the brushless synchronous machine of the present invention has been described above, and next, another embodiment of the present invention in which individual parts are implemented using other means will be described.

(1) About the rectifier 3 If a light-igniting thyristor is used for the rectifier 3, the O/E converter 8 can be omitted, and the light-igniting can be carried out from the multi-terminal optical connector 1 rotor 62-4 to the optical cable 62-3. Since signals can be supplied, the number of devices mounted on rotating parts can be reduced.

However, the optical signal that must be transmitted from the stator side to the rotor side needs to be stronger, and therefore the optical signal transmission mechanism section is larger than the above-described optical signal transmission mechanism section.

If it is difficult to increase the size of the optical signal transmission mechanism section, an optical signal amplification function may be added to the rotating section.

(2) Regarding the stator side light emitting section (a) An optical lens (concave lens) can be placed at the tip of one optical cable coming from the control device to form the stator side light emitting section. In this case, although it is easy to spread the luminous flux, it is necessary to carefully consider the distance between the light emitting part and the light receiving part so that the luminous flux does not spread too much.

(b) Light receiving section 6 shown in Fig. 2 (D) and Fig. 2 (E)
2, the unit photoreceptor 621 is made up of an optical fiber 62-IA, but similarly, the light emitting part on the stator side can be made of an optical fiber instead of the optical cable 61-1.

(c) The signal generated by the control device 5 may be left as an electric signal, and the light emitting surface section 61-3 may be configured with an appropriate number of light emitting diodes to serve as a light emitting section.

(3) Regarding the rotor side light receiving section (a) The light receiving section can also be constructed from a set of commercially available photo transistors. In such a case, there is an advantage that the optical signal can be received and converted into an electrical signal at the same time. This is more convenient when using an electric ignition thyristor.

In this case, many ineffective parts (parts that do not actually feel light) are formed on the light receiving surface, so consideration must be given to the light emitting surface of the stator side light emitting section.

(b) A photo-l-transistor with a special shape can also be used as the light receiving section. For example, it is possible to use transistors 1 to 1 of a rectangular large-area light receiving section.

Although this has a cost problem, it has the advantage that a light receiving section with a large effective area can be easily constructed.

(c) A configuration may also be adopted in which rectangular lenses (convex lenses) are arranged on the surface of the light receiving section to optically condense the light and receive it at the cross section of the Fo I/1 transistor or the optical cable.

(4) Regarding the protection and inspection equipment of the optical signal transmission mechanism (a) The optical signal transmission mechanism has a drawback in that the transmission efficiency of optical signals decreases due to contamination of its light emitting surface and light receiving surface.

In this case, in order to prevent contamination of a synchronous machine that is operated continuously for a long period of time, it is preferable to cover the optical signal transmission mechanism section with a cover having a sealed structure. Note that a specific technique for sealing a rotating body having shafts on both sides is adopted in a hydrogen-cooled rotor synchronous machine, and this can be used.

(b) It is recommended to monitor the contamination of the optical signal transmission mechanism during operation.

As shown in FIG. 3, the O/E converter 9A converts the light reception signals of each phase into electrical DC signals. Next, the low value selection circuit 9B selects the lowest value signal among the input signals of each phase. This signal is input to the comparison circuit 9C and compared with the set value of the comparison circuit 9C. As a result, if the input signal value is smaller than the set value, a signal is output to the amplifier circuit 9D. As a result, the output of the amplifier circuit 9D causes the rotating part transmitting winding 9 to
Excite E. In the rotating part transmitting winding 9E, a detection winding 9 is installed in the fixed part so as to intersect with the magnetic flux generated by the rotating part transmitting winding 9E.
F is provided.

Note that the detection winding 9F crosses the magnetic flux once per rotation of the rotor, and does not need to cross the magnetic flux all the time.

With such a configuration, when the light transmission efficiency decreases due to contamination or the like, the light reception signal (pulse signal) decreases.

The low value selection circuit 9B converts this signal into a DC electrical signal.
By passing through the phase, a signal proportional to the light transmission efficiency of the phase with the lowest light transmission efficiency is output.

When this output signal becomes less than the allowable value (set value of the comparator circuit), the rotating part transmitting winding 9E is excited, and the rotating part transmitting winding 9E is excited.
Due to the magnetic flux produced by E, a pulse voltage (one pulse per rotation of the rotor) is output to the detection winding 9F of the fixed part. By detecting this pulse voltage on the fixed side, it is possible to detect that the light transmission efficiency has decreased below a set value.

Although the above detailed description of the invention has been made with respect to a synchronous generator, the present invention can be similarly applied to a synchronous motor.

Furthermore, although the explanation has been made based on a system in which the AC exciter is excited by a power source obtained from a shaft-coupled PMG, the gist of the present invention does not change no matter what excitation system is adopted for this part.

[Effects of the Invention] As explained above, according to the present invention, the field voltage can be directly controlled without using an AC exciter, so a high-speed response brushless synchronous machine can be realized.

Furthermore, the present invention has the remarkable effect of realizing a high-speed response brushless synchronous machine, which was conventionally considered to be an epoch-making method but could not be realized in a large capacity machine.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a brushless synchronous machine showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram of an optical signal transmission mechanism that is a component of the brushless synchronous machine shown in FIG. A) is a diagram showing the positional relationship of the components of optical signal transmission, (B) is an external view of the light emitting part of the optical signal transmission mechanism, and (C)
) is a surface view from the direction of the arrow in figure (B), figure (D) is an external view of the light receiving part of the optical signal transmission mechanism, and figure (E) is figure (E).
D) is a surface view from the direction of the arrow; FIG. 3 is a block diagram of a device for detecting changes in characteristics of the optical signal transmission mechanism; FIG. 4 is a block diagram of a conventional brushless synchronous machine;
6 are block diagrams of a conventional thyristor brushless synchronous machine. ■...Synchronous generator, IA...field winding of synchronous generator, 2...AC exciter, 2A...field winding of AC exciter, 3...rectifier, 5... Control device, 6A... Optical signal transmission mechanism, 61... Light emitting section, 62... Light receiving section.

Claims (2)

[Claims] (1) A rotor of a rotating field type synchronous machine, a rotating armature type AC exciter, and the rotating armature voltage of this AC exciter is converted to DC and supplied to the rotor winding of the synchronous machine. In a brushless synchronous machine configured by installing a controllable rectifier on the rotating shaft, the number of phases of the field winding of the synchronous machine is adjusted to transmit the control signal from the control device to the rotor part as an optical signal. A plurality of light emitting parts correspondingly provided on the stator part, and a plurality of annular light receiving parts provided on the rotation axis opposite to the light emitting parts for receiving optical signals from these light emitting parts, A brushless synchronous machine characterized in that the rectifier is controlled by optical signals received by these annular light receiving sections. (2) An optical signal transmission mechanism deterioration detection device is provided that detects when the lowest signal of each phase signal received by the rotor section is below a set level and transmits it to the stator section. The brushless synchronous machine according to claim 1.