JPS6234599B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a generator drive device that drives a turbine and generates electricity using high-pressure steam and low-pressure steam obtained in a ship.

BACKGROUND ART Exhaust gas economizer turbo power generators have been known as systems for recovering exhaust heat from diesel main engines in ships. The steam turbine of this turbo power generation device is driven by high-pressure steam in order to obtain high cycle efficiency, and waste heat recovery from the diesel main engine is also used to supply steam at a pressure above a certain level (medium pressure) for miscellaneous purposes such as heating. In this case, only the high-temperature and medium-temperature portion of the exhaust gas could be recovered, and the remaining waste heat remained unrecovered.

In addition, as shown in FIG. 1, the low-pressure evaporator 1 which obtains steam by lowering the pressure in order to recover the waste heat of the low-temperature portion of the exhaust gas that remains unrecovered is connected to the high-pressure evaporator 3 of the exhaust gas economizer 2, as shown in FIG. and is provided on the downstream side of the intermediate pressure evaporation section, and these evaporation sections 1 and 3 drive a single turbo generator 4 (5 is a mixed pressure turbine, 6 is a generator) for power generation, while the low pressure steam A system in which a booster turbine 9 is connected to a propulsion unit 8 via a reducer 7 (10 is a superheating section, 11 is a main diesel engine, and 12 is a supercharged air economizer) is also considered, but it is possible to recover the energy from waste heat. If the demand for power consumed within the ship exceeds the power required to drive the generator, then other means such as diesel generators must be operated to make up for the shortfall. This diesel generator is not only less efficient than the diesel main engine, but also requires the use of high quality heavy oil as its fuel. Furthermore, due to the nature of this diesel generator, it is not possible to operate at extremely low loads, so even if the shortfall in power obtained from waste heat recovery is only a small amount compared to the power demand, it is necessary to purchase a diesel generator to cover the power demand. The diesel generator is operated to generate electric power at its operable level, while the single turbo generator generates electric power corresponding to the difference between the electric power generated at this operable level and the demand electric power. I would have to drive to Therefore, even if there is an amount of waste heat that can be recovered in a single turbo generator, the amount of waste heat will not be effectively utilized as long as the above conditions are met.

In addition, if there is a surplus in the turbine output obtained by waste heat recovery, the output of the generator 6 (13 is a turbine) drives the electric motor 14, and the power is transferred to the reducer 7. (The main diesel engine 11 is connected to this reducer.) It is also possible to apply force to the propulsion machine 8 via the main diesel engine 11. Since efficiency and gear transmission efficiency intervene, the overall efficiency decreases.

The present invention was devised to solve the above-mentioned inconveniences, and its purpose is to generate high-pressure steam and low-pressure steam in an exhaust gas economizer, and to supply the low-pressure steam with other sources of low-pressure steam in the ship. By using high-pressure steam and low-pressure steam to drive a mixed-pressure turbine connected to a generator, with or without adding low-pressure steam, the generator was also driven by the main diesel engine. While using all of the steam for power generation, the surplus is used for propulsion, or the shortage is compensated for by using a power transmission mechanism with high power transmission efficiency from the main diesel engine, which is fuel efficient and can use low-quality heavy oil. The object of the present invention is to provide a generator drive device that obtains the desired results.

Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 3 shows a marine generator drive device 20 of the present invention. 21 is a generator, the rotating shaft of which is connected to the output shaft of the mixed pressure turbine 22 (mixed pressure turbine 22
and the generator 21 constitute a mixed pressure turbine generator. ) On the other hand, it is connected to the output shaft of a transmission (transmission (speed increaser)) 23. The input shaft of the transmission 23 is connected to the rotational drive shaft (speed-increasing output shaft) of the speed reducer 24 . That is, the input/output shaft of the transmission 23 coaxially connects the rotating shaft of the generator 21 and the speed increasing output shaft of the reducer 24. The input shaft of the reducer 24 is connected to the output rotating shaft of a main diesel engine (hereinafter referred to as a diesel main engine) 25. Further, a propulsion output shaft of the reducer 24 is connected to a propulsion device 26 . The reducer 24 and the transmission 23 consist of a gear train.

27 is an exhaust gas economizer (steam generator) that recovers waste heat from the main diesel engine 25, and a superheating section 28 and a high-pressure evaporation section (high-pressure steam generation section) 29 are installed on the upstream side of the exhaust heat system, and a low-pressure evaporation section 29 is installed on the downstream side. (low-pressure steam generation section) 30 is provided. 31 is a medium pressure evaporation section. High pressure evaporation section 29
is connected to the high-pressure steam injection part of the mixed pressure turbine 22 via the superheating part 28 or not. The low-pressure evaporator 30, which together with the high-pressure evaporator 29 constitutes the steam supply system 32, uses exhaust gas of 150-160°C or less to
It generates steam of 1.0Kg/cm ² G, which is also used for low-pressure evaporation from other low-temperature heat sources inside the ship, such as the supercharged air economizer 33 of the diesel main engine 25, the jacket fresh water section, the solar heat collection section, etc. It is also connected to the low pressure steam injection section of the mixed pressure turbine 22.

Next, the operation of the apparatus of the present invention having the above configuration will be explained.

When the main diesel engine 25 of the ship is operated, its exhaust gas is vented to the exhaust gas economizer 27, and the exhaust gas is vented to the exhaust gas economizer 27 from the high-pressure evaporator 29, the low-pressure evaporator 30, and additionally or not from other low-pressure evaporators, respectively. , high pressure steam as well as low pressure steam are generated.

Both of these steams are guided to corresponding steam injection parts of the mixed pressure turbine 22 to drive the turbine 22, and converted into electrical energy by the generator 21, which is then supplied to power-demanding equipment such as inside a ship.

If there is an amount of waste heat recovered that exceeds the power demand, in other words, if surplus power is obtained from the output of the turbine 22, that power powers the propulsion device 26 via the transmission 23 and reduction gear 24. used for. Since the load on the propulsion device 26 generally far exceeds the surplus power, all of the surplus power is used to drive the propulsion device. Therefore, all of the steam supplied to the turbine 22 is effectively consumed. As a result, the exhaust gas economizer 27
The amount of waste heat recovered can be increased. Moreover, since the above-mentioned power transmission is gear transmission, power transmission efficiency is improved.

In addition, if the amount of power generated by driving the steam generated by waste heat recovery is less than the power demand on board the ship, in other words, if there is a shortage in turbine output, the shortage will occur. The amount is replenished from the diesel main engine 25 in the following manner. That is, the power shortage is transmitted from the diesel main engine 25 to the generator 21 via the speed reducer 24 and the transmission 23 while automatically or manually operating the transmission 23 to obtain the required rotational speed of the generator 21.

In this way, the voltage for the insufficient power is supplemented not by the diesel generator but by the diesel main engine, which has good fuel efficiency and can use low-quality heavy oil, so the problem that occurs when using a diesel generator, that is, the use of recovered waste heat, can be suppressed, and the turbo There is no need to run a generator, which improves energy efficiency and reduces fuel costs. Moreover, since the above-mentioned power transmission is gear transmission, power transmission efficiency is improved.

In the above embodiment, the transmission may be configured as a multi-stage switching transmission, or a speed increaser is connected to the output shaft of the diesel main engine, and the output shaft is connected to the generator via the transmission or the multi-stage switching transmission. It may also be connected to a rotating shaft. The above-mentioned device is not limited to ships, but can equally be applied to power generation using the exhaust heat of a diesel engine that has sufficient exhaust heat and whose rotation speed is matched to the rotation speed of the generator.

As is clear from the above description, the following effects can be obtained according to the present invention.

The high and low pressure steam obtained from the exhaust gas economizer and the low pressure steam obtained from other low temperature heat sources inside the ship can be fully utilized effectively.

Therefore, the amount of waste heat recovered can be increased, which results in fuel cost savings.

The degree of energy saving is improved in a state where the turbine output is insufficient to meet the power demand.

Diesel main engine power can be transmitted to the generator with high efficiency and used for power generation. Further, the turbine output can be provided to the propulsion device for propulsion with high efficiency.

[Brief explanation of the drawing]

Figure 1 is a diagram showing an example of a device configured in one mode in which steam generated by an exhaust gas economizer is used for power generation, and Figure 2 is a diagram showing an example of a device configured in one mode in which steam generated in an exhaust gas economizer is used for power generation. FIG. 3 is a diagram showing an example of a constructed device, and FIG. 3 is a diagram showing a marine generator drive device of the present invention. In the figure, 20 is a marine generator drive device, 21, 2
2 is a mixed pressure turbine generator, 23 is a transmission, 25 is a diesel main engine, 26 is a propulsion unit, 29 is a high pressure evaporator, 30 is a low pressure evaporator, and 32 is a steam supply system.

Claims (1)

[Claims] 1 A diesel main engine that drives a propulsion machine, a reducer that transmits the output of the diesel main engine to the propulsion machine as rotational driving force, and a high-pressure steam generation section provided on the upstream side of the exhaust heat system of the diesel main engine. and a steam supply system comprising a low-pressure steam generation section provided on the downstream side of the exhaust heat system, a mixed turbine driven by high-pressure steam and low-pressure steam from the steam supply system, and a mixed turbine rotated by the mixed turbine. A generator is driven and supplies its output to power supply equipment, and the rotation shaft of the generator and the rotation drive shaft of the reduction gear are connected coaxially, and the rotation drive force of the mixed turbine is used to generate the generator. When the rotational speed of the generator is lower than the required rotational speed, the rotational driving force from the reducer is transmitted to increase the speed of the generator, and when the rotational speed of the generator exceeds the required rotational speed, the rotational driving force is transmitted to the generator. A generator drive device comprising: a transmission device that applies rotational driving force to the reduction gear from a rotating shaft of a generator to rotationally drive the propulsion device.