JPS6011635A - Turbocompressor system - Google Patents

Abstract

PURPOSE:To make the starting of a compressor performable with the irreducible minimum of energy without fail, by feeding the compressor with a starting ags from the inlet side, while decreasing the feed pressure by degrees in proportion to an increase in the heat energy quantity given to the inlet side of a turbine. CONSTITUTION:In time of starting, a charging valve 3 is closed, while a control valve 13 for a starting gas feed device 9 is opened instead. With this constitution, a high pressure starting gas discharged out of a high pressure gas source 11 is fed to an inlet 1a of a compressor 1 and simultaneously the starting ags passing through the compressor 1 is led into an inlet 2b of a turbine 2 whereby both the turbine 2 and the compressor 1 get rotating. Under this condition, it the amount of heat energy given from an air chamber 7 of a fuel cell 6 and a combustion furnace 8 to the side of the turbine inlet 2b is gradually increased, power of the turnbine 2 increases. With increment of the heat energy quantity, opening of the control valve 13 is gradually decreased, and at the point that feed pressure drops up to atmospheric pressure, the charging valve 3 is opened and made to change over to self-excitation.

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a turbo compressor system that can be applied to various industrial plants such as jet engines for aircraft and fuel cell power generation plants. .

(b) Prior Art As a turbo compressor system typified by a jet engine, as shown in Fig. 1, there is a compressor a whose inlet is open to the atmosphere, and an inlet connected to the outlet of the compressor a via a gas passage. Some devices include a connected turbine C for driving a compressor, and a heat adding means d that is interposed in the middle of the gas passage and applies thermal energy to the inlet side of the turbine C. However, this type of system is difficult to start up and has many problems. That is, in the conventional system, a drive source f such as a motor is connected to the rotating shaft e of the compressor a and the turbine C via a transmission g at the time of startup. Then, the drive source f is operated to rotate the compressor a and the turbine C, and when the compressor a has a constant compression ratio, the heat atomizing means d is ignited to shift to self-excited operation. That's what I do. This requires a starting drive source other than a turbo compressor, which typically requires very high rotational speeds. Therefore, various protection circuits are required, and there are problems in that the system J as a whole becomes complicated and large-scale in addition to having defects that can lead to major malfunctions even with the slightest malfunction.

In addition, as a starting method that does not use a mechanical drive source such as a morph, it is considered to blow high-pressure gas for starting into the inlet of the turbine, but in this method, the flow rate on the compressor side at the time of starting is There is a problem in that the compressor is prone to surging because there is very little.

(c) The present invention was made with attention to such circumstances,
We have developed a turbo compressor system that enables reliable starting with minimal energy without the need for a complex and large-scale starting device, and that can effectively prevent surging in the compressor that easily occurs during startup. The purpose is to provide.

(D) Structure In order to achieve the above object, the present invention supplies starting gas from the inlet side of the compressor, and increases the supply pressure of this starting gas by the amount of thermal energy applied from the heat adding means to the inlet side of the turbine. The supply pressure is gradually decreased as the supply pressure increases, and when the supply pressure has decreased to atmospheric pressure, self-excited operation can be started.

(E) Example Hereinafter, an example in which the present invention is applied to an air compression section of a fuel cell power generation plant will be described with reference to FIG.

As shown in FIG. 2, in the turbo compressor system according to the present invention, a compressor 1 is driven by a turbine 2 having a variable nozzle 2a. and,
The inlet 1a of the compressor 1 is opened to the atmosphere via an air supply passage 4 with an air supply valve 3 interposed therebetween, and the outlet 1b of the compressor 1 and the inlet 2b of the turbine 2 are connected to each other.
and are connected via a gas passage 5. The gas passage 5 is formed by providing a main passage part 5a and a sub passage part 5b in parallel, and an air chamber 7 of a fuel cell 6 which functions as a heat adding means is interposed in the middle of the main passage part 5a. In addition, a combustor 8 serving as a second heat adding means is interposed in the middle of the sub-passage portion 5b. Further, a starting gas supply means 9 is provided in a portion of the air supply passage 4 subsequent to the air supply valve 3. The starting gas supply means 9 includes a high-pressure gas source 11 such as a cylinder that discharges high-pressure starting gas, a starting gas guide path 12 that connects this high-pressure gas source 11 to the air supply passage 4, and this starting gas guide path 12. A control valve 13 is provided in the middle of the guideway 12 to open and close the guideway 12 steplessly.

Next, the operation of this embodiment will be explained. When starting FJA, the air supply valve 3 is closed and the control valve 13 of the starting gas supply means 9 is opened.

5- Then, the high-pressure starting gas discharged from the high-pressure gas source 11 is supplied to the inlet 1a of the compressor 1, and the starting gas that has passed through the compressor 1 is supplied to the turbine 2.
The turbine 2 and compressor 1 start rotating. In this state, if the amount of thermal energy applied from the air chamber 7 of the fuel cell 6 and the combustion furnace 8 to the inlet 2b side of the turbine 2 is increased, the power of the turbine 2 tends to increase, so that the power of the turbine 2 tends to increase. Operation continues even if the gas supply pressure is lowered. Therefore, the opening degree of the control valve 13 of the starting gas supply means 9 is gradually reduced within a range that allows the operation of the turbine 2 to be maintained, and when the supply pressure of the starting gas has decreased to atmospheric pressure, the intake valve 13 is Open to switch to self-excited operation. This step can be explained using a formula as follows. Letting the amount of work of the compressor 1 be HC, the Hc is expressed by the following formula. Here, Cpa is the specific heat of the gas 6, WC is the mass flow m of the gas, 'rlc is the humppressor efficiency,
TCin is the inlet temperature of the compressor 1, pcin is the inlet pressure, pcout is the outlet pressure, and k is the specific heat ratio.

On the other hand, if the amount of work of the turbine 2 is Ht, then the Ht is
It is expressed by the following formula. Here, Cpt is the specific heat ratio of the gas, the mass flow rate of the gas, Nt is the turbine efficiency, Ttin is the inlet temperature of the turbine 2, ptin is the inlet pressure, pto+j
t is the outlet pressure, 1(' is the specific heat ratio. Compressor 1
and turbine 2 are operating, Hc = H
j holds true, but the air chamber 7 and the combustor 8
When the amount of heat given to the starting gas increases and the inlet temperature Ttin of the turbine 2 rises, the amount of work l-1t of the turbine 2 shown by equation (1) increases. Therefore,
As the amount of heat supplied increases, the amount of work of the compressor 1 expressed by equation (2) can also be increased, and the inlet pressure pcin of the compressor 1 can be gradually reduced. Then, when the inlet pressure pcin reaches atmospheric pressure, it is possible to smoothly shift to complete self-excitation operation. By the way, in the self-excited operation in this embodiment, the combustion amount of the combustor 8 and the opening degree of the variable nozzle 2a of the turbine 2 are appropriately controlled to maintain a constant pressure in the air chamber 7 of the fuel cell 6, e.g. It is designed to supply ATA air.

In the above embodiments, the present invention was applied to the air compression part of a fuel cell power generation plant, but the present invention is not limited to this type of system, but can also be applied to other types of turbo compressor systems. The same applies.

Further, the starting gas supply means is not limited to one using a gas cylinder or the like, but may be one using a blower or a small air compressor.

Furthermore, the working gas is not limited to air.

(f) Effects Since the present invention has the above-described configuration, the following effects can be obtained.

First, since starting can be performed without using high-speed rotating machinery such as a motor or transmission, or various protective devices, the system can be simplified and the energy required for starting can be minimized. I can do it.

Further, since the starting gas is supplied to the inlet side of the compressor instead of directly to the inlet side of the turbine, a sufficient flow rate of the compressor can be ensured even in the starting operation mode. Therefore,
It is possible to effectively prevent surging, which tends to occur at the time of starting, and to ensure stable starting performance.

Furthermore, if there is surplus high-pressure gas, that gas can be supplied to the inlet of the compressor using the starting gas supply means, so idling operation can be performed with the heat addition means such as the combustor stopped. There is also the convenience of being able to

[Brief explanation of the drawing]

FIG. 1 is a system explanatory diagram showing a conventional example, and FIG. 2 is a system explanatory diagram showing an embodiment of the present invention. 1...Compressor 9-1a...Population 1b...Output 1'' 2...Turbine 2b...Inlet 3...Air supply valve 5...Gas A path 7...Heat adding means (Air chamber) 8...Heat addition means (combustor) 9...Starting gas supply means Agent Patent attorney Hiroshi Akazawa 10- Continuation of Figure 2, page 1 (Plastic combination Author: Masanao Ando Nakagyo, Kyoto City) Shimadzu Corporation Sanjo Factory, 1 Kyokuwabara-cho (West) Kyokuwabara-cho (Plastic inventor: Isaka Hirokyo City) Inside Sanjo Factory, Shimadzu Corporation, 1 Kyokuwabara-cho, West Nakagyo-ku

Claims (1)

[Claims] a compressor whose inlet is open to the atmosphere via an air supply valve; a turbine for driving the compressor whose inlet is connected to the outlet of the compressor via a gas passage and whose outlet is open to the atmosphere; a heat adding means which is interposed and applies thermal energy to the inlet side of the turbine; and a starting gas having a pressure higher than atmospheric pressure is supplied to the inlet of the compressor at the time of startup when the air supply valve closes to operate the turbine; and a starting gas supply means for gradually decreasing the supply pressure of the starting gas in accordance with an increase in the amount of heat supplied by the heat adding means, while satisfying the condition that the operation of the starting gas can be maintained, the supply pressure of the starting gas is A turbo compressor system characterized in that it is configured to open the air supply valve and shift to self-excited operation when the air pressure drops to atmospheric pressure.