JPS61258700A - Shaft generator utilizing waste heat - Google Patents

Abstract

PURPOSE:To always obtain necessary generating power while effectively utilizing waste heat by rotatably driving one of the field and the armature of a shaft generator by a main engine, and driving the other by a steam turbine utilizing the waste heat of the main engine. CONSTITUTION:The rotational shaft 25 of a main engine 12 is coupled with the rotational shaft 24 of the armature 23 of a shaft generator 21. The shaft 25 is coupled through a gear train 30, the first driver 31, the second driver 33 and a gear train 32 with the gear 26 of the field 22 of the generator 21. A steam turbine 19 is driven by thermal energy of exhaust gas G of the engine 12. The rotational shaft 27 of the turbine 19 is coupled through a gear 28 with the gear 26 of the field 22. A controller 35 controls a steam valve 17, the first driver 31 and the second driver 33 in response to the rotating speed of the engine 12 to hold the output frequency of the generator 21 at the prescribed value.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a shaft power generation device that is mainly mounted on a ship and driven by a main engine for propulsion and a steam turbine that utilizes the waste heat of the main engine. It is something.

[Prior Art] Conventionally, in order to effectively utilize the waste heat of the main diesel propulsion engine mounted on a ship, for example, a steam turbine was operated using waste heat from an exhaust gas economizer, main engine air cooler, etc. Methods that have been adopted include connecting a steam turbine to a main engine and using it as propulsion power, or driving a generator with the steam turbine and using it as electric power.

[Problems to be Solved by the Invention] However, in the former method, a gear type power transmission device is usually used as a means to connect the steam turbine to the main engine, but the long-stroke, low-speed main engines that have been adopted recently have problems with rotational torque. Since the fluctuations in the transmission torque are large, in the gear transmission device, if the fluctuation torque exceeds the average transmission torque, so-called hammering occurs, in which the tooth surfaces of the gears come into contact with each other, causing damage to the tooth surfaces.

On the other hand, in the latter method, when the main engine is partially loaded, the waste heat energy of the main engine alone cannot cover the demand for electricity within the ship. Furthermore, in ships with low main engine output, there is little waste heat energy even when the main engine is at its rated output, so waste heat energy alone may not be enough to cover the onboard conditioning power.

This invention was made in view of the above-mentioned problems, and by driving a generator using both the power of the main engine and its waste heat energy, it is possible to constantly supply the necessary amount of power, and it is also possible to use a hammer. The purpose is to provide a shaft power generation device that uses waste heat without the problem of rings.

[Means for Solving the Problems] In order to achieve the above object, the present invention first sets the field part and armature of the shaft generator coupled to the main engine to be rotatable, and One of the magnetic part and the armature is rotationally driven by the main engine, and the other is rotationally driven by a steam turbine that utilizes waste heat from the main engine. Furthermore, the control device
The relative rotational speed between the field part and the armature is maintained constant by controlling the rotational speed of at least one of the main engine or the steam turbine.

[Operation] According to the present invention, since the shaft generator is driven by both the main engine and the steam turbine that utilizes waste heat, the required capacity of power generation can be obtained at all times. Further, since the main engine and the steam turbine are electromagnetically coupled via the shaft generator and not connected by a gear transmission device, hammering of the gear due to torque fluctuations of the main engine does not occur.

Furthermore, the rotational speed of the main engine changes due to changes in the rotational speed setting and changes in the load from the propeller, and the rotational speed of the steam turbine also changes depending on the amount of waste heat energy. Since the relative speed is held constant, the output frequency of the shaft generator is held constant.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

In Figure 1, the propulsion fi consisting of a screw propeller
ll is driven by a main engine 12 consisting of a diesel engine. Exhaust gas G is discharged from the main engine 12 to the outside via a supercharger 13 and an exhaust passage 14, and an exhaust gas economizer 15 is provided in the exhaust passage 14. Water or steam W from another boiler is supplied to the gas economizer 15 from an inlet pipe 16, and the steam S obtained in the exhaust gas economizer 15 passes through an outlet pipe 18 having a steam valve 17 to become steam. turbine 19
The steam turbine 19 is guided to drive the steam turbine 19.

Reference numeral 21 denotes a synchronous shaft generator, in which an armature 23 is arranged inside a cylindrical field part 22, and electric power is extracted from a slip ring 29 provided at the rotation of the armature 23 @24. Of course, the armature 23 may have a cylindrical shape, the field portion 22 may be arranged inside the armature 23, and the electric power may be taken out from a slip ring 29 provided on the armature 23.

The rotating shaft 24 of the armature 23 is rotatably supported by a generator casing (not shown) via a bearing, and the field section 22 is rotatably supported by the rotating ring 24 via a bearing (also not shown). Supported. This axis-launched TL machine 2
The output frequency of No. 1 is determined by the relative number of rotations (rotational speed) between the field section 22 and the armature 23.

The structure in which both the field section 22 and the armature 23 are rotatable in this way has already been adopted in the technology of super synchronous motors in which the field section is rotated only during startup to suppress the starting load, and is well known. There is, and it is also disclosed in the specification and drawings of Japanese Patent Application No. 1982-262815 (filed on December 14, 1982), which is the earlier application by the applicant, so the details of this structure will be omitted here. do. The difference between the above-mentioned prior invention and the present invention is that in the prior invention, one of the field part or the armature is rotated by a variable rotation speed shaft, and in order to maintain the external force and the output frequency at a constant value, In contrast, in the present invention, the field part is rotated not in order to maintain the output frequency at a constant value, but in order to actively utilize both the power of the main engine 12 and the waste heat energy. 22 or armature 2
3 is driven by the main engine 12, and the other is driven by a steam turbine 19 that utilizes waste heat, which is not disclosed in the above-mentioned prior application.

A rotating shaft 24 of the armature 23 is connected to a rotating shaft 25 of the main engine 12, and the armature 23 is rotationally driven by the main engine 12. On the other hand, the field section 22 is connected to the steam turbine 19 via a gear 26 fixed thereto and a gear 28 coupled to a rotating shaft 27 of the steam turbine 19, and is rotationally driven by the steam turbine 19. be done.

A gear train 30 is connected to the rotating shaft 25 of the main engine 12.
A first drive 31, such as a hydraulic pump/hydraulic motor or a generator/electric motor, is connected, while the field section 22
The gear 26 is also connected via the gear 32 to a hydraulic pump/hydraulic motor or generator/? The motive is like the second
The front drives 31.33 are connected hydraulically or electrically by connection means 34. Further, the front drive machine 31.33 is connected to a control device M35, and according to commands from this control device 135, one of the redrives 41131, 33 operates as a hydraulic pump or a generator, and the other operates as a hydraulic motor or electric motor. When activated, energy is exchanged between the front drive machines 31 and 33.

Further, the opening degree of the steam valve 17 provided in the steam outlet pipe 18 is also controlled by the control device 35. This control device 35
is a device equipped with an actuator that drives the steam valve 17 using air pressure, electricity, or oil pressure, and detects the frequency of the output current flowing through the power supply line 36 connected to the slip ring 29, so that the frequency remains constant. Next, the opening degree of the steam valve 17 is controlled to control the rotation speed of the steam turbine 19, that is, the rotation speed of the field section 22. 37 is a switch inserted in the power supply line 36.

In the above configuration, the main engine 12 has a speed of 1100 rpm, for example.
The shaft rotates at a relatively low speed to drive the propulsion machine 11 and the armature 23 of the shaft generator 21. On the other hand, exhaust gas G from the main engine 12
The amount of heat, that is, waste heat, is recovered as steam S by the exhaust gas economizer 15, and this steam S drives the steam turbine 19, which in turn drives the shaft generator 21.
drive the field section 22 of.

In this way, the armature 23 of the shaft generator 21 is driven by the main engine 12, and the field part 22 is driven by the steam turbine 19, so when the field part 22 and the armature 23 rotate in opposite directions, The main atZ and steam turbine 19 are
The power supply to the shaft power generator 4!121 is shared by the ratio of the rotational speeds of the field section 22 and the armature 23. For example, when the armature 23 rotates at 1100 rpm and the field section 22 rotates at 350 rpm in the opposite direction to the armature 23, the main engine 1
2 and the steam turbine 19 supply power at a ratio of 1:3.5 to drive the shaft power generator #121. In this way, since the shaft generator 21 is driven by both the main engine 12 and the steam turbine that utilizes waste heat, the necessary capacity of power generation can always be obtained while effectively utilizing the waste heat.

In addition, the main engine 12 and the steam turbine 19 are connected to a shaft generator 21
are electromagnetically coupled via the armature 23 and the field section 22, and are not connected by a gear transmission device, so that hammering of the gear due to torque fluctuations of the main engine does not occur.Furthermore, the field section 22 By setting the rotation speed of the armature 23 high, for example, the rotation speed of the armature 23 can be increased to 100
Since the main engine 12, which has a low speed of about 1100 rpm, can be directly connected to the armature 2-3 without going through a reduction gear, the structure is simplified and the hammering at the reduction gear can be reduced. This problem does not arise.

Next, control of the output frequency by the control device 35 will be explained.

For example, due to fluctuations in the load on the propulsion machine 11,
When the rotational speed of the armature 23 increases, the rotational speed of the armature 23 also increases. When the armature 23 and the field section 22 are rotating in opposite directions, when the rotational speed of the armature 23 increases,
The relative speed between the armature 23 and the field section 22 increases, and the output frequency of the shaft generator 21 becomes higher than a constant value. This frequency fluctuation is detected by the control device 35 as a change in the frequency of the current flowing through the power supply line 36, and the control device 35 increases its output air pressure, voltage, or oil pressure to drive the steam valve 17. The amount of steam supplied to the steam turbine 19 is reduced by reducing the opening degree, thereby reducing the rotation speed of the steam turbine 19, that is, the rotation speed of the field section 22. Thereby, the relative rotational speed of the main engine 12 and the steam turbine 19 is kept constant (45 rpm), and the output frequency of the shaft generator 21 is kept constant.

Further, when the rotational speed of the main engine 12 decreases, contrary to the above, the control device 35 increases the opening degree of the steam valve 17 and increases the rotational speed of the field section 22, thereby increasing the rotational speed of the main engine 12. The relative rotational speed of the steam turbine 19 is kept constant, and the output frequency of the shaft power generator 921 is kept constant.

Similarly, the amount of steam from the exhaust gas economizer 15 fluctuates, for example due to changes in ambient temperature, causing the steam turbine 1'9 to
Also when the rotational speed of the field section 22 fluctuates, the output of the shaft power generator 4121, $$, deviates from a constant value. At this time as well, the control device 35 operates by detecting the output frequency and controls the steam valve opening and opening.
Adjust the rotational speed of the steam turbine 19'@*, main, machine 12
The relative rotational speed of the steam turbine 19 is kept constant, and the output of the shaft generator 21 is kept constant.

In this way, since the relative rotational speed of the main engine 12 and the steam turbine 19 is always kept constant, the output frequency of the shaft generator 21 is kept constant, so that stable electric power can be supplied.

Furthermore, in this embodiment, the first and second driving machines 31
．． 33, the amount of steam from the exhaust gas economizer 15 is greatly reduced, and if it is insufficient to keep the output frequency constant, this shortage is compensated for, and
When the amount of steam from the exhaust gas economizer 15 is excessive, the energy is returned to the main Ia 12 and effectively used as part of the propulsion power.

In other words, first, the rotation speed of the armature 23 is 1100 rpm,
When the field section 22 is operated at a rotation speed of 35 rpm, the amount of steam S from the exhaust gas economizer 15 decreases significantly due to a drop in ambient temperature, etc., and even if the steam valve 17 is fully opened, the output If it becomes impossible to increase the rotation speed of the steam turbine 19 as much as necessary to maintain the frequency at a constant value,
As the rotational speed of the steam turbine 19 decreases, the rotational speed of the gear 26 decreases below 35 rpm. In this case, the control device 135''/Wall] Suddenly, due to that command, the first drive machine 31
．． "5" Te, [i.e., the main engine] 2 supplies energy to -7 of the second drive machine 33, and this second drive machine 3
3,'', 4.45: 'Energy is supplied to the gate-driven field section 22~, that is, the axis-driven ~,,,@@41,
Since the amount of steam S tends to rise towards 3'S4 rpm, the output frequency of the shaft generator '21 is kept at a constant value. is mainly performed by adjusting the opening of the steam valve 17 by the control device 35, but auxiliary control is as follows:
This is also done by the above-mentioned two-part motive 31,33.

Next, when the amount of steam S from the exhaust gas economizer 15 increases, the rotation speed of the steam turbine 19 increases,
The rotation speed of the field section 22 becomes higher than 35 Orpm. In this case, energy is supplied from the second drive machine 33 to the first drive machine 31 according to a command from the control device 35, and this energy is returned to the main engine 12 via the gear train 30. At this time, since the rotational speed of the field section 22 driven by the second driver 33 tends to decrease toward the 3-sorp range, auxiliary control is performed to keep the output frequency at a constant value.

By the way, the amount of steam S from the exhaust gas economizer 15,
In other words, if the waste heat energy covers the power demand on board and exceeds a certain range, if the field section 22 and the armature 23 are rotated in the same direction, the steam turbine 19 alone can be used to generate the shaft generator 21. Power is supplied, and surplus power from the steam turbine 19 is returned to the main engine 12 through the armature 23. For example, when the armature 23 rotates at 1100 rpm and the field section 22 rotates at 55 Orpm in the same direction as the armature 23, the shaft generator 21 is supplied with 4501550 of the power generated by the steam turbine 19, and the main engine 12 1001550 will be returned to you.

This, together with the operation of the drive machines 31 and 32 described above, enables more effective return of energy to the main engine 12 and control to maintain the output frequency of the shaft generator 21 at a constant value. As a means for switching the relative rotation direction of the field section 22 and the armature 23, for example, a forward/reverse rotation switching clutch is interposed on the rotating shaft 27 of the steam turbine 19, and by operating this clutch, the field section There are means such as switching the direction of rotation of the steam turbine 22 or using a type of steam turbine 19 that can rotate in forward and reverse directions.

FIG. 2 shows a second embodiment of the invention.

In the same figure, the rotating shaft 25 of the main engine 12 is connected to a gear train 30 to generate 1! /A drive machine 41 consisting of an electric motor is connected, and this drive machine 41 is connected to a first converter 42,
It is connected to the power supply line 36 via a DC reactor 43 and a second converter 44 . The driving machine 41 and the first and second converters 42, 44 are also electrically connected to the control device 35 and operate according to commands from the control device 35.

In the configuration shown in FIG. 2, the main engine 12 or the steam turbine 1
As in the first embodiment shown in FIG. 1, the control device 3
5 operates to adjust the opening degree of the steam valve 17.
The above output frequency is maintained at a constant value.

Next, when the amount of steam 5KS from the exhaust gas economizer 15 decreases significantly, and even if the steam valve 17 is fully opened, the rotation speed of the steam turbine 19 cannot be increased to the extent necessary to maintain the output frequency at a constant value. , due to the decrease in the rotation speed of the steam turbine 19, the rotation speed of the field section 22 is lower than that of the 350 rP layer. As a result, the output frequency of the shaft generator 21 decreases and the output voltage also decreases, so the control device 35
The drive machine 41 operates as a generator according to a command from the power supply line 36, and supplies power to the power supply line 36. That is, the insufficient electric power is replenished from the main engine 12 via the drive machine 41. At this time, since it is not expected that the rotation speed of the field section 22 will return to the 350 rpm layer, the shaft generator 2
The effect of keeping the output frequency of 1 at a constant value cannot be expected.

On the other hand, the amount of steam S from the exhaust gas economizer 15 increases, the rotation speed of the steam turbine 19 increases, and the field part 22
When the rotational speed of the shaft generator 21 increases to more than 350 rpm, the output frequency of the shaft generator 21 increases and the output voltage also increases, so the drive machine 41 operates as an electric motor and the surplus power is returned to the main machine 12. Effectively used as propulsion power. At this time, the rotational speed of the field section 22 is about to decrease toward 350 rpm, which has the effect of keeping the output frequency of the shaft generator 21 at a constant value. Auxiliary control is provided to keep the output frequency of 21 at a constant value.

Note that the driving machines 31 and 33 may be omitted from the embodiment shown in FIG. 1, and the first converter 42, 33 may be omitted from the embodiment shown in FIG.
The DC reactor 43 and the second converter 44 may be omitted. In that case, when there is sufficient waste heat energy, the output frequency of the shaft generator 21 can be kept constant by controlling the steam valve 17 by the control device 35. can be kept. Also,
When waste heat energy is insufficient, the power generation amount of the shaft power generator 45121 is reduced and the rotation speed of the field section 22 is reduced to 350 rpm.
By keeping the output frequency constant,
To generate electricity for the shortage, a separate power generation unit 1j1 (example:

This can be compensated for by operating a diesel generator (for example, a diesel generator).

Furthermore, unlike the above embodiments, a device is provided as a control device that detects the output frequency and adjusts the amount of fuel supplied to the main engine 12, and this device controls the main engine 12 so that the output frequency is constant. You can control the rotation speed,
The rotation speeds of both the steam turbine 19 and the main engine 12 may be controlled. That is, the rotational speed of at least one of the main engine or the steam turbine may be controlled so that the relative rotational speed between the field section and the armature is constant.

Further, in each of the above embodiments, the control device 35
The steam valve 17 is controlled by detecting fluctuations in the output frequency of the field section 2. However, unlike this, the control device 35
Alternatively, the rotation speeds of the armature 2 and the armature 23 may be individually detected and compared, and the steam valve 17 may be controlled by detecting a change in the relative rotation speeds. Furthermore, it goes without saying that a galvanic type generator may be used as the shaft generator 21.

[Effects of the Invention] As described above, according to the present invention, the shaft generator is driven by both the main engine and the steam turbine that utilizes waste heat, thereby effectively utilizing the waste heat.

The required amount of power generation is always available. In addition, the main engine and the steam turbine are electromagnetically coupled via the shaft generator and are not coupled by a gear transmission.
No gear hammering occurs due to main engine torque fluctuations.

Furthermore, although the rotational speeds of the main engine and steam turbine that drive the field section and armature are likely to fluctuate, the relative speed between the field section and armature is maintained constant by the control device. Since the output frequency of the shaft generator is kept constant, stable power can be supplied.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing one embodiment of the present invention, and FIG. 2 is a schematic diagram showing another embodiment. 12... Main engine, 15... Exhaust gas economizer, 19
...Steam turbine, 21...Shaft generator, 22...
Field part, 23... Armature, 35... Control device.

Claims (1)

[Claims] (1) Both the field part and the armature are set to be rotatable, one of the field part and the armature is rotationally driven by the main engine, and the other is rotationally driven by a steam turbine that utilizes the waste heat of the main engine. A waste product characterized by comprising a shaft generator and a control device that controls the rotational speed of at least one of the main engine or the steam turbine to maintain a constant relative rotational speed between the field part and the armature. A shaft power generation device that uses heat.