JP2008507659A - Dynamically controlled compressor - Google Patents

Abstract

In a system with two or more compressors, the present invention provides a suitably sized container or tank for one or both of the suction or discharge tubes of the plurality of compressors. This container or tank serves as a means to counteract this change so that if the state of the first compressor changes, it will not immediately impact the other compressors.
[Selection] Figure 2

Description

  The present invention relates to a compressor. In particular, the present invention relates to a dynamically controlled compressor system and method.

  As is known in the art, a centrifugal compressor has an operating range called a compressor map, which is limited by a condition called a choke and another condition called a surge.

  Current centrifugal compressors pump gas when operating within surge and choke points. If a centrifugal compressor remains operating in a surge condition for a short period of time, its impeller can overheat and damage the entire machine. Compressor manufacturers use various types of surge detection devices, that is, devices that stop the machine and prevent damage if a surge is detected, and try to protect the compressor from operation in such a damaged state. ing.

  For the purpose of saving energy, recent centrifugal compressors have a speed controller added to widen their operating range, in which case the compressor control system has become dynamic. Up to this point, the compressor was turned on or off, but the compressor became more intelligent and the dynamic nature of the controller allowed the compressor to respond to state changes. In the latest version currently available on the market, the Applicant has a centrifugal compressor with a fully dynamic control that continuously optimizes the speed and position of the inlet guide vanes to maximize efficiency. it can. Until this time, centrifugal compressors have been primarily a single compressor system, but in recent years when two compressors are applied to one machine they are operated in parallel, Loading (loading) and unloading (no load) are performed only by using (IGV), and loading and unloading are performed at the same rate and at the same time by being controlled by one controller.

  Currently, compressors have a compressor map programmed into a control unit for adjusting the speed and operating the inlet guide vanes when necessary to maximize performance. In such a dynamic control system, the compressor provides that its operating parameters are adapted when the system state changes or when the system load changes.

  In the case of a system with a single compressor, the speed and inlet guide vane settings are actively changed to optimize the performance of the dynamic control of the centrifugal compressor, that is, in various operating conditions and capacity requirements. The control to be performed is processed by the control logic of the compressor itself.

  As shown in FIG. 1, the first compressor Comp1 and the second compressor Comp2 include two or more compressors arranged in parallel between the low pressure side (suction pipe) and the high pressure side (discharge pipe). In such a system, the operating state of the first compressor is directly affected by changes in the pump capacity of the second compressor. This may be the case when, for example, one of the compressors, the condenser or the evaporator is not of an appropriate size, and the piping to the compressor and the piping from the compressor are not connected independently, or a plurality of compressors Are connected in parallel, and the point of interconnection between the compressors is a common point or pipe, and the capacity of the connection point is not adequate to compensate for changes in the first compressor, so this is the second This can happen when the compressor has an immediate effect.

  In the case of such multiple compressors, which are themselves intelligent, centrifugal compressor systems and methods are currently known in the art that allow dynamic control over performance over a wide operating range. is necessary.

  Specifically, the system includes a plurality of compressors, and is at least a first compressor and a second compressor, and at least a first compressor and a second compressor in parallel between a low pressure side and a high pressure side. One or more inertial vessels connected to one of the suction pipes and the discharge pipes, wherein the one or more inertial containers operate at least the first compressor and the second compressor. A system is provided that serves as a means to attenuate state changes.

  Furthermore, there is provided a method for controlling a compressor system including two or more compressors arranged in parallel between a low pressure side and a high pressure side, wherein one suction pipe and one discharge pipe of the two or more compressors are provided. A method is provided comprising connecting one or more inertial containers to at least one of them.

  Other objects, advantages and features of the present invention will become apparent upon reading the following non-limiting description of embodiments using examples in conjunction with the accompanying drawings.

  For example, in the case of a refrigeration system such as an air conditioner, the compressor load varies as a function of time and temperature, and thus pressure. These changes affect the operation of the compressor, which in response adjusts its speed and inlet guide vanes.

  Such a dynamic control system can be applied to conventional systems using other types of positive displacement compressors, such as reciprocating compressors, scroll compressors, screw compressors, and the like. In the case of an air compressor, the compressor responds as the load demand changes in the process to which it is applied, such as a manufacturing process.

  In a system including two or more compressors, the present invention provides a container or a tank of an appropriate size for one or both of the suction pipe and the discharge pipe of the plurality of compressors. When the machine changes, it has no immediate effect on other compressors and the container acts as a means to counteract the change.

  FIG. 2 shows a parallel piping system with a header arrangement to reduce the effect of changes in the operation of the first compressor on the second compressor, where a common low pressure tank 12 is connected to the compressor Comp1. The high-pressure tank 14 is connected to the discharge pipes of the compressors Comp1 and Comp2 while being connected to the suction pipe of the Comp2.

  In the parallel piping system shown in FIG. 3, auxiliary tanks are provided in the discharge pipes 14a and 14b and the suction pipes 12a and 12b of the compressors Comp1 and Comp2, respectively. 2 Reduce the impact on the compressor.

  FIG. 4 shows a system of multiple compressors that are sealed or semi-sealed. In this system, in a hermetically sealed or semi-sealed compressor, compressor housings are provided, which are appropriately sized to function as inertial tanks, thereby providing external inertial tanks. There is no need to provide it.

  FIG. 5 shows a system with two compressors sharing the same housing, which must be appropriately sized to function as an inertia tank, thereby providing an external inertia tank. Disappear. This type of system can have one or more outlet ports and inlet ports (see FIGS. 5A and 5B).

  FIG. 6 shows an alternative embodiment in which low and high pressure inertia tanks are provided. These inertia tanks are modular in design, and are connected by a flange joint or a joint provided by, for example, Virtualic, and the inlet pipe and the outlet pipe are connected on one side.

  In FIG. 7, the inlet pipe and outlet pipe of the inertia tank can be connected to any part of the inertia tank. When assembled modularly, the inlet and outlet pipe connections are made in the middle of the stack to balance gas distribution and reduce the size of individual inertia tanks.

  It should be noted that refrigerant can enter and exit the system from any of one or more ports.

  In the system shown in FIG. 8, two compressors, one condenser, and one evaporator are connected in parallel to the common condenser container 32, and in parallel from the common evaporator container 30. The condenser and the evaporator have the appropriate size, but these are generally not required.

  As will be appreciated by those skilled in the art, the present invention uses a plurality of dynamically controlled compressors to replace one large compressor or one of an inlet point and an outlet point. Or, through both, the suction and discharge tubes can be used in applications where it is necessary to connect to a heat exchanger. An example of this is a water cooler with one inlet to the condenser and one outlet from the evaporator. There is no problem if the compressor requires only one compressor, but if more than two compressors are required to obtain the required capacity, a plurality of compressors can be In general, it is not enough to connect with simple piping that is usually used. Piping connection points need to be sized appropriately so as not to have an immediate impact on other compressors operating in the system.

  The present invention can be applied to a system including two or more compressors. For example, the systems of FIGS. 2-8 can be expanded when they are first installed or by adding additional compressors as needed at a later date. Each system can have a function of being piped using a single or a plurality of suction pipes and discharge pipes.

  Although the present invention has been described according to its embodiments as described above, modifications can be made to the invention without departing from the spirit and teachings of the invention as described above.

It is a figure showing the piping composition of a plurality of compressors piped in parallel known technically to which "conventional technology" is added. 1 illustrates a system according to an embodiment of the present invention. FIG. 6 is a diagram illustrating a system according to another embodiment of the present invention. FIG. 6 illustrates a system according to yet another embodiment of the present invention. FIG. 5 illustrates an alternative to the embodiment of FIG. FIG. 5 illustrates an alternative to the embodiment of FIG. FIG. 6 illustrates a system according to yet another embodiment of the present invention. FIG. 7 shows an alternative to the embodiment of FIG. FIG. 2 shows a system with a plurality of compressors piped in parallel to and from a common vessel, namely a condenser and an evaporator, where an inertial tank is probably not needed.

Claims (12)

In a system with multiple compressors,
At least a first compressor and a second compressor in parallel between the low pressure side and the high pressure side;
And at least one inertial container connected to one of the suction pipe and the discharge pipe of the first compressor and the second compressor,
A system with a plurality of compressors, wherein the inertial container functions as a means for weakening a change in operating state of the first compressor and the second compressor.   A low-pressure tank connected to suction pipes of the first compressor and the second compressor; and a high-pressure tank connected to discharge pipes of the first compressor and the second compressor. The system by the several compressor of Claim 1 provided.   The system according to claim 1, wherein each of the first compressor and the second compressor is connected to a low-pressure tank and a high-pressure tank.   The first compressor and the second compressor are selected from sealed or semi-sealed compressors, and the inertial container includes a housing of the first compressor and a housing of the second compressor. A system using a plurality of compressors according to Item 1.   The system according to claim 1, wherein the first compressor and the second compressor are housed in a common housing, and the inertial container is formed by the common housing.   The system according to claim 1, wherein the inertial container includes a modular low-pressure tank and a modular high-pressure tank. In a method for controlling a compressor system comprising two or more compressors arranged in parallel between a low pressure side and a high pressure side,
Connecting at least one inertial vessel to one or more of at least one suction pipe and discharge pipe in the two or more compressors.   The method includes connecting a common low pressure tank connected to a suction pipe of the two or more compressors and connecting a common high pressure tank connected to a discharge pipe of the two or more compressors. The method described in 1.   8. The method of claim 7, comprising connecting each of the two or more compressors to a low pressure tank and a high pressure tank.   The two or more compressors are selected from hermetically or semi-sealed compressors, and each of the compressors has a housing, and the method connects each housing to a low pressure side and a high pressure side. 8. The method of claim 7, comprising:   8. The method of claim 7, wherein the two or more compressors are housed in a common housing, and the method includes connecting the common housing to a low pressure side and a high pressure side.   8. The method of claim 7, comprising connecting the modular low pressure tank to the low pressure side and connecting the modular high pressure tank to the high pressure side.

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