Compressor system, compressor control device, and compressor control method

Abstract

To suppress deterioration of power efficiency of the entire compressor system according to conditions such as clogging of a filter of each compressor, in operation of the compressor system comprising a plurality of compressors.SOLUTION: In a compressor system having a plurality of compressors and a compressor controller that controls the operation of the plurality of compressors, each of the compressors comprises a filter that filters air, a compressor body that compresses air, and detection means of detecting a physical quantity correlated with the pressure loss of the compressor body. The compressor controller preferentially operates a compressor having higher power efficiency according to the physical quantity detected by the detection means among the plurality of compressors, and restricts the operation of a compressor having lower power efficiency.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a compressor system, a compressor control device, and a compressor control method. [Background technology]

[0002] A compressor system that generates compressed gas using multiple compressors is configured. In such a compressor system, the discharge piping systems of the multiple compressors are merged into one to discharge the compressed gas, and the number of compressors that are operating or stopped is controlled to change depending on the usage status of the compressed gas.

[0003] Compressors are typically equipped with an intake filter to ensure the quality of the discharge air and facilitate equipment maintenance. For example, in the case of a packaged compressor in which the compressor main unit and other components are housed in a housing, the housing has an opening through which air that has been filtered to remove dust and other debris is taken in from the outside via the intake filter. In addition, for example, in both packaged compressors and compressors without a housing in which the compressor unit is exposed to the outside, an intake filter is attached to the intake portion of the compressor main unit.

[0004] A clogged intake filter causes a loss of intake pressure, which in turn reduces the amount of discharged air and power loss, resulting in a decrease in the compressor's power efficiency. Therefore, it is recommended that the intake filter be cleaned or replaced regularly, but compressor users sometimes forget to do so.

[0005] In response to this, Patent Document 1 discloses a technology for notifying a user or the like that it is time to replace an intake filter. That is, Patent Document 1 discloses a technology for a package-type compressor that includes a filter arranged at an intake port of a compressor housing, a pressure detector arranged near the intake port on the inside side of the housing, and an external device, and that notifies the user that the filter is clogged (i.e., notifies the user that replacement or cleaning is required) by firing at the external device when the pressure detected by the pressure detector is equal to or lower than a predetermined pressure. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2019 / 082552 Summary of the Invention [Problem to be solved by the invention]

[0007] However, while the above-mentioned conventional technology can notify the user of the need to clean or replace the intake filter, if the user forgets to replace or clean the filter despite receiving the notification, power loss due to increased suction pressure loss will continue. Furthermore, the notification for replacement or other such action is made when the suction pressure is below a predetermined pressure, but a certain amount of clogging is tolerated until just before the pressure drops below the predetermined pressure, resulting in a corresponding power loss and a risk of reducing the compressor's power efficiency. To solve this problem, if the predetermined pressure value that triggers the notification is set lower, the notification cycle will be shortened, resulting in more frequent notifications and potential problems.

[0008] The present invention has been made in consideration of the above points, and one object of the present invention is to suppress a decrease in the power efficiency of the entire compressor system in operation of a compressor system including multiple compressors, depending on the status of the filters of each compressor, such as clogging. [Means for solving the problem]

[0009] In order to solve this problem, the present invention provides a compressor system having a plurality of compressors and a compressor control device that controls operation of the plurality of compressors, each of the compressors having a filter that filters air, a compressor main body that compresses the air, and detection means that detects a physical quantity that is correlated with the pressure loss of the compressor main body, and the compressor control device is characterized in that, of the plurality of compressors, operation of a compressor having a higher power efficiency according to the physical quantity detected by the detection means is given priority, and operation of a compressor having a lower power efficiency is restricted. [Effects of the Invention]

[0010] According to the present invention, for example, in the operation of a compressor system including a plurality of compressors, it is possible to suppress a decrease in the power efficiency of the entire compressor system depending on the state of clogging of the filters of each compressor, etc. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a configuration diagram of a compressor system according to a first embodiment. [Figure 2] 1 is a configuration diagram of a compressor (constant speed compressor) according to a first embodiment. [Figure 3] 1 is a configuration diagram of a compressor (variable speed compressor) according to a first embodiment. [Figure 4] 1 is a configuration diagram of a compressor control device according to a first embodiment. [Figure 5] FIG. 3 is a diagram showing the configuration of a pressure loss information table according to the first embodiment. [Figure 6] FIG. 3 is a diagram showing the configuration of a pressure loss determination table according to the first embodiment. [Figure 7] FIG. 3 is a configuration diagram of an operating period allocation table according to the first embodiment. [Figure 8] FIG. 3 is a diagram showing the configuration of an operation pattern table according to the first embodiment. [Figure 9] 4 is a flowchart showing a process for generating pressure loss information and operating period allocation information according to the first embodiment. [Figure 10] 4 is a flowchart showing a driving pattern information generation process according to the first embodiment. [Figure 11] FIG. 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to Application Example 1 of Embodiment 1 (when a total of four machines, including two constant speed machines and two variable speed machines, are operating normally). [Figure 12] 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to Application Example 1 of Embodiment 1 (when compression loss occurs in a variable speed gearbox). FIG. [Figure 13] 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to Application Example 1 of Embodiment 1 (when compression loss occurs in a constant speed machine). FIG. [Figure 14]FIG. 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to Application Example 2 of Embodiment 1 (when a total of three machines, two constant speed machines and one variable speed machine, are operating normally). [Figure 15] 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to application example 2 of embodiment 1 (when compression loss occurs in a variable speed gearbox). FIG. [Figure 16] 10 is an explanatory diagram of generation of operation pattern information (operation pattern table) according to application example 2 of embodiment 1 (when compression loss occurs in a constant speed machine). FIG. [Figure 17] FIG. 3 is an explanatory diagram of a display screen in the compressor control device according to the first embodiment. [Figure 18] 10 is a flowchart showing a driving pattern information generation process according to the second embodiment. [Figure 19] 19 is a detailed flow of step S24 of the driving pattern information generation process of FIG. 18. [Figure 20] 19 is a detailed flow of step S25 of the driving pattern information generation process of FIG. 18. [Figure 21] 19 is a detailed flow of step S26 of the driving pattern information generation process of FIG. 18. [Figure 22] 19 is a detailed flow of step S27 of the driving pattern information generation process of FIG. 18. [Figure 23] 19 is a detailed flow of step S28 of the driving pattern information generation process of FIG. 18. [Figure 24] 19 is a detailed flow of step S29 of the driving pattern information generation process of FIG. 18. DETAILED DESCRIPTION OF THE INVENTION

[0012] Embodiments and examples of the present invention will be described in detail below with reference to the drawings. The embodiments and examples of the present invention disclose a compressor system including one or more compressors (constant speed compressors) that produce compressed air by rotating the compressor body under constant speed control, and one or more compressors (variable speed compressors) that produce compressed air by rotating the compressor body under variable speed control using an inverter or the like. In this compressor system, the constant speed compressor and the variable speed compressor are appropriately assigned between full load operation and capacity control operation depending on the pressure loss (hereinafter referred to as "pressure loss") of intake filters, separator elements, etc., and the compressor system as a whole produces and supplies compressed air to compressed air consumers connected to a piping network with better power efficiency.

[0013] In the following drawings for explaining the embodiments and examples, the same reference numerals are used to indicate configurations or processes having the same or similar functions, and subsequent explanations will be omitted. Furthermore, the embodiments and examples can be combined in part or in whole within the scope and consistency of the technical concept of the present invention. Furthermore, in the following embodiments and examples, explanations of previously described configurations and processes will be omitted, and differences will be mainly explained.

[0014] In the following explanation, information that produces an output for an input may be described using expressions such as "xxx table," but this information may be data of any structure. Therefore, "xxx table" can also be called "xxx information."

[0015] Furthermore, in the following description, the configuration of each table is an example, and one table may be divided into two or more tables, or all or part of two or more tables may be one table.

[0016] [Embodiment 1] <Configuration of Compressor System 1 According to First Embodiment> FIG. 1 is a configuration diagram of a compressor system 1 according to an embodiment. The compressor system 1 is configured to include M compressors (constant speed compressors F1, F2, . . . , FM) and N compressors (variable speed compressors V1, V2, . . . , VN). M and N are natural numbers including 0. M=0 means that there is no constant speed compressor, and N=0 means that there is no variable speed compressor. The constant speed compressors Fi (i=1, 2, . . . , M) and variable speed compressors Vj (j=1, 2, . . . , N) are collectively referred to as compressors 4.

[0017] The constant speed machine Fi controls the compressor body in load (compressed air production) and unload (idle operation) to perform constant speed control to produce compressed air.The variable speed machines Vj each have an inverter and PID (Proportional-Integral-Differential) function, and perform variable speed control to produce compressed air by changing the rotation speed.

[0018] The compressed air outlets of the constant speed machine Fi and the variable speed machine Vj are connected together and connected to an air tank (tank) 5. The compressed air produced by the constant speed machine Fi and the variable speed machine Vj is supplied to a line for using compressed air via the air tank 5.

[0019] A pressure sensor 6 is attached to the air tank 5, and a measurement signal from the pressure sensor 6 that measures the pressure inside the air tank 5 is input into the management device 2. The management device 2 is a cloud-based device that collects measurement information from the compressor system 1, such as the measurement signal from the pressure sensor 6 and the measurement signals from the sensors of the constant speed machine Fi and the variable speed machine Vj, and provides a display based on the various measurement information to the user and outputs various alerts. The management device 2 outputs various measurement information from the compressor system 1 to the compressor control device 3. Note that the management device 2 may be an on-premise device together with the compressor control device 3.

[0020] The compressor control device 3 is an on-premise device. Based on various measurement information of the compressor system 1 notified from the management device 2, the compressor control device 3 determines the operation and operation limitations of the constant speed unit Fi and the variable speed unit Vj in accordance with the air usage ratio of the compressed air produced by the compressor system 1. The compressor control device 3 creates an operation pattern table 31d (FIG. 8, also referred to as "operation pattern information") described below based on the determined operation and operation limitations. The compressor control device 3 may be a cloud-based device together with the management device 2.

[0021] <Configuration of Compressor (Constant Speed) Fi> 2 is a configuration diagram of a compressor (constant speed compressor) Fi according to embodiment 1. The main body and the like of the constant speed compressor Fi are housed in a housing 41. The peripheral surface of the housing 41 is provided with an outside air inlet 42 for taking in outside air and an exhaust port 43 for discharging air from inside the housing 41 to the outside. Part of the air drawn in from outside the housing 41 by the rotation of the fan 44 flows into the intake section of the compressor main body 45 and becomes compressed air, and part of the air cools the compressor main body 45 and other accessories before being discharged to the outside from the exhaust port 43.

[0022] An outside air filter 46 is installed as a dust collecting member at the outside air inlet 42 of the housing 41. In addition, an intake filter 47 is also arranged upstream of the intake section of the compressor main body 45. Dust is removed from the air flowing into the housing 41 from the outside air inlet 42 by the outside air filter 46. Dust is removed from the air drawn into the compressor main body 45 from the intake section of the compressor main body 45 by the intake filter 47.

[0023] A pressure sensor 48 is disposed near the outside air inlet 42. The pressure sensor 48 detects the degree of negative pressure that occurs when air is sucked in.

[0024] The control unit 49F has an arithmetic control unit (e.g., a CPU (Central Processing Unit)) that executes arithmetic processing and control processing based on a program, and a memory unit (e.g., a ROM (Read Only Memory), a RAM (Random Access Memory)) that stores the programs and the results of the arithmetic processing. The control unit 49F controls the electromagnetic contactor 50F based on an operation command received from the compressor control device 3, drives and stops the motor 51, and operates the constant speed machine Fi in capacity control operation or full load operation. In capacity control operation of the constant speed machine Fi, the amount of compressed air produced is increased or decreased by adjusting and repeating periods of loading and unloading at a constant rotation speed. In full load operation of the constant speed machine Fi, the amount of compressed air produced is kept constant by regularly repeating periods of loading and unloading at a constant rotation speed.

[0025] Furthermore, the control unit 49F transmits the suction pressure detected by the pressure sensor 48 to the management device 2.

[0026] The motor 51 is connected to a commercial power source 52 via an electromagnetic contactor 50F. When the pressure in the air tank 5 detected by the pressure sensor 6 rises to the operating pressure, the control unit 49F opens the contacts of the electromagnetic contactor 50F to stop the motor 51 and stop the supply of compressed air from the compressor main body 45 to the air tank 5 (unload). When the pressure in the air tank 5 detected by the pressure sensor 6 falls to the return pressure, the control unit 49F closes the contacts of the electromagnetic contactor 50F to drive the motor 51 and restore the supply of compressed air from the compressor main body 45 to the air tank 5 (load).

[0027] The compressor body 45 is, for example, a reciprocating compressor, and includes a cylinder, a piston, an intake valve, and a discharge valve. The rotational motion of the motor 51 is transmitted via a pulley, a belt, etc., and is further converted into reciprocating motion via a crankshaft, etc., and transmitted to the piston. This causes the piston in the cylinder to reciprocate, changing the volume of the working chamber within the cylinder. The intake valve opens, the discharge valve closes, and the volume of the working chamber increases, drawing air into the working chamber (intake process). Then, the intake valve closes, and the discharge valve closes, and the volume of the working chamber decreases, compressing the air in the working chamber (compression process). Then, the intake valve closes, and the discharge valve opens, and the compressed air is discharged from the working chamber (discharge process).

[0028] The constant speed machine Fi generally has better power efficiency during full load operation (operation at 100% load) than the variable speed machine Vj.

[0029] <Configuration of Compressor (Variable Speed ​​Machine Vj)> 3 is a configuration diagram of a compressor (variable speed machine Vj) according to embodiment 1. Compared to the constant speed machine Vi, the variable speed machine Vj includes a control unit 49V instead of the control unit 49F and an inverter 50V instead of the electromagnetic contactor 50F. Otherwise, the variable speed machine Vj is the same as the constant speed machine Vi.

[0030] The control unit 49V has an arithmetic control unit (e.g., CPU) that executes arithmetic processing and control processing based on a program, and a memory unit (e.g., ROM, RAM) that stores the program and the results of the arithmetic processing. The control unit 49V controls the inverter 50V to drive the motor 51 based on an operation command received from the compressor control device 3, and causes the variable speed machine Vj to perform capacity control operation or full load operation. In capacity control operation of the variable speed machine Vj, the rotation speed of the motor 51 is adjusted to follow the target pressure in the air tank 5, thereby increasing or decreasing the amount of compressed air produced. In full load operation of the variable speed machine Vj, the rotation speed of the motor 51 is set to full load, and the maximum amount of compressed air produced is kept constant.

[0031] Furthermore, the control unit 49V transmits the suction pressure detected by the pressure sensor 48 to the management device 2.

[0032] The control unit 49F controls the rotation of the inverter 50V and adjusts the amount of compressed air supplied from the compressor main body 45 to the air tank 5 so that the pressure in the air tank 5 detected by the pressure sensor 6 falls within the fluctuation range of the target pressure.

[0033] The variable speed machine Vj generally has better power efficiency during capacity control operation (operation with varying load) than the constant speed machine Vi.

[0034] <Configuration of compressor control device 3 of embodiment 1> 4 is a configuration diagram of the compressor control device 3 according to the embodiment 1. The compressor control device 3 includes a storage 31, a processor 32, a memory 33, and peripheral devices .

[0035] The storage 31 is a storage device having a predetermined storage area, and stores a pressure loss information table 31a, a pressure loss determination table 31b, an operation period allocation table 31c, and an operation pattern table 31d.

[0036] The processor 32 includes one or more processors, and may be, for example, a microprocessor such as a CPU, or may be another type of processor such as a GPU (Graphics Processing Unit). The processor may be single-core or multi-core. The processor may also be a processor in the broader sense, such as a hardware circuit (for example, an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit)) that performs some or all of the processing.

[0037] The processor 32 executes a program read from a predetermined storage area such as the storage 31 in cooperation with the memory 33, thereby realizing an information generating unit 32a, a driving pattern information generating unit 32b, and a driving control unit 32c.

[0038] The information generating unit 32a generates a pressure loss information table 31a and an operation period allocation table 31c. The operation pattern information generating unit 32b generates an operation pattern table 31d. The processing of the information generating unit 32a and the operation pattern information generating unit 32b will be described later with reference to FIG.

[0039] The operation control unit 32c outputs commands for operation and operation restrictions (such as reduction of operation period and restriction of rotation speed) to the constant speed machine Fi and the variable speed machine Vj according to the information in the operation pattern table 31d generated by the operation pattern information generation unit 32b.

[0040] The peripheral devices 34 include devices such as a communication interface that enables the compressor control device 3 to communicate with the management device 2, the constant speed machine Fi, and the variable speed machine Vj, an output device such as a display that outputs information, and an input device that accepts information input.

[0041] The pressure loss information table 31a, the pressure loss determination table 31b, the operation period allocation table 31c, the operation pattern table 31d, the information generator 32a, and the operation pattern information generator 32b of the compressor control device 3 may be provided on a cloud server. In this case, the operation controller 32c of the compressor control device 3 receives operation instructions based on the operation pattern table 31d created on the cloud server and controls the operation of each compressor 4.

[0042] <Configuration of Pressure Loss Information Table 31a in First Embodiment> 5 is a diagram showing the configuration of a pressure loss information table 31a according to embodiment 1. The pressure loss information table 31a records the "presence or absence of pressure loss" for each compressor 4 of the constant speed compressor Fi and the variable speed compressor Fj. The "presence or absence of pressure loss" is determined based on the suction pressure detected by the pressure sensor 48 of each compressor, which is periodically collected, and on the pressure loss determination table 31b.

[0043] For example, if "Presence or absence of pressure loss" is "0", no pressure loss is occurring in the corresponding compressor 4. If "Presence or absence of pressure loss" is "1", pressure loss is occurring in the corresponding compressor 4.

[0044] <Configuration of pressure loss determination table 31b in embodiment 1> 6 is a configuration diagram of the pressure loss determination table 31b according to the first embodiment. The pressure loss determination table 31b stores reference information for determining whether the suction pressure detected by the pressure sensor 48 of each compressor 4 is "normal" or "pressure loss occurs." For example, when the "suction pressure P" satisfies "P1≦P" (P1 is a predetermined value), it is determined that the corresponding compressor 4 has a "pressure loss Q" of "Q1≦Q" (Q1 is a predetermined value).

[0045] If there is a pressure loss, the operation of the corresponding compressor 4 is restricted. For example, if the "suction pressure P" is "P1≦P", the operating period of the corresponding compressor in the operating period allocation table 31c described below is "reduced by 2 / 3" from the default information (reduced operating period), as shown in "Degenerate", and the reduced area is allocated to another compressor. "Area" refers to an area in the operating pattern table 31d that represents the power consumption characteristics of each compressor 4 that constitutes the compressor system 1, after the power consumption characteristics of the entire compressor system 1 are broken down into each compressor 4. The default information refers to information in which areas are evenly allocated to each compressor 4 in the operating period allocation table 31c when no pressure loss occurs in any of the compressors 4.

[0046] From the viewpoint of energy conservation, it is desirable to allocate the mass removed from a certain compressor 4 due to degeneration caused by compression loss to a compressor 4 that has the same performance (constant speed or variable speed) as the compressor 4 from which the mass has been removed and that does not experience compression loss.

[0047] However, it is not always possible to allocate all of the reduced mass to compressors 4 that have the same performance as the compressors 4 that have reduced mass due to degeneration caused by compression loss and that do not experience compression loss. In this case, it may be necessary to allocate the reduced mass to compressors 4 with different performance or to operate a compressor 4 with compression loss. Therefore, the mass allocation is selected in a way that improves or optimizes the power efficiency of the entire compressor system 1, taking into account the power efficiency minus the compression loss of each compressor 4.

[0048] In the pressure loss determination table 31b, the suction pressure abnormality detected by the pressure sensor 48 of each compressor 4 is not classified into a single level of "Pressure loss present", but the present invention is not limited to this and two or more levels may be used depending on the degree of the suction pressure abnormality. In the case of two or more levels, the higher the degree (level) of the pressure loss abnormality, the more severely the operation of the corresponding compressor 4 is restricted.

[0049] Furthermore, the operation restriction of the compressor 4 includes stopping operation and degeneration. Degeneration is not limited to the above-mentioned "reduction in the operation period" but may also be operation within a rotation speed range (for example, a low speed range) in which power efficiency does not decrease.

[0050] In this embodiment, the pressure loss is assumed to be a suction pressure loss due to clogging of the fresh air filter 46 of the fresh air inlet 42, and the occurrence of this compression loss is detected based on the suction pressure of the fresh air filter 46. However, this is not limiting. For example, the pressure loss may be assumed to be a suction pressure loss due to clogging of the intake filter 47 of the intake section of the compressor main body 45, and the occurrence of this pressure loss may be detected based on the temperature of the intake filter 47 of the compressor main body 45 or the surrounding temperature of the intake section. Alternatively, the compression loss may be assumed to be a pressure loss due to clogging of a separator element that filters the compressed air discharged from the compressor main body 45 to remove lubricating oil from the compressor main body 45, and the occurrence of this pressure loss may be detected based on a value obtained by subtracting the discharge pressure of the compressed air from the compressor main body 45 from the pressure in the air tank 5 detected by the pressure sensor 6. In other words, the occurrence of compression loss in the compressor 4 may be detected based on at least one physical quantity that is correlated with compression loss, such as the suction pressure or temperature of the filter.

[0051] <Configuration of operation period allocation table 31c> Fig. 7 is a diagram showing the configuration of an operating period allocation table 31c according to the first embodiment. The operating period allocation table 31c records the number of squares to be secured for each compressor 4, representing the operating period for operating each compressor 4, in an operating pattern table 31d (Fig. 8) to be described later. For example, a "constant speed compressor" with "compressor" F1 is assigned an "operating period (number of squares)" of "a1". If no compression loss occurs in any compressor, each compressor 4 is assigned the same number "{(M+N) 2 +(M+N)} / (M+N)" = "M+N+1" is assigned to each compressor 4. If a compression loss occurs in the compressor 4, the "operating period (number of masses)" for each compressor 4 is reduced, and the reduced period is allocated to the "operating period (number of masses)" of another compressor 4.

[0052] <Configuration of operation pattern table 31d> 8 is a configuration diagram of the operation pattern table 31d according to embodiment 1. The operation pattern table 31d is created by accumulating designations of the compressors 4 to be operated and the power consumption characteristics of each of the constant speed and variable speed compressors 4 in order to derive a target working air compression ratio.

[0053] In operation pattern table 31d, the horizontal axis represents the air consumption ratio (%) and the vertical axis represents the power consumption ratio (%). Figure 8 shows the case of a total of M constant speed machines and N variable speed machines (M+N), with the horizontal axis taking values ​​of 0 to 100 to 200 to 300... to (M+N) x 100... to 300 to 200... 100 and the vertical axis taking values ​​of 0 to 100 to 200 to 300... to (M+N) x 100.

[0054] In the graph of FIG. 8, the region where the power consumption characteristics are roughly represented by the diagonal lines of the boxes is called the capacity adjustment region. In the capacity adjustment region, the compressor 4 performs capacity control operation. In the graph of FIG. 8, the region where the entire box is filled in is called the full load region. In the full load region, the compressor 4 performs full load operation. Generally, in capacity control operation in the capacity adjustment region, variable speed machines have better power consumption characteristics than constant speed machines, and in full load operation in the full load region, constant speed machines have better power consumption characteristics than variable speed machines.

[0055] In FIG. 8, since no compression loss occurs in any of the compressors, each compressor 4 has the same number {(M+N) 2 By equally allocating the squares of "{M+N} / (M+N)", each compressor 4 is operated for an equal period of time.

[0056] For example, if the air usage ratio of the entire compressor system 1 is 100 to 200, the target air usage ratio can be achieved by operating the constant speed machine F1, which is a constant speed machine, at a full load and at a constant speed, and operating the variable speed machine V1, which is a variable speed machine, at a variable speed.When the air usage ratio shifts from 100 to 200 to 200 to 300, the target air usage ratio can be achieved by operating the constant speed machine F2, which is a constant speed machine, at a full load and at a constant speed, in addition to operating the constant speed machine F1, which is a constant speed machine, at a full load, and operating the variable speed machine V1, which is a variable speed machine, at a variable speed.

[0057] Furthermore, when the air consumption ratio is between 300 and 200, the target air consumption ratio can be achieved by operating the constant speed machines F1 and F2 at a constant speed under full load, and operating the variable speed machine VN at a variable speed. When the air consumption ratio shifts from 300 to 200 to 200 to 100, the constant speed machine F1 is stopped, the constant speed machine F2 is operated at a constant speed under full load, and the variable speed machine VN is operated at a variable speed, thereby achieving the target air consumption ratio.

[0058] <Pressure loss information and operating period allocation information generation process> 9 is a flowchart showing the pressure loss information and operating period allocation information generation process according to the first embodiment. The pressure loss information and operating period allocation information generation process is executed repeatedly at a predetermined cycle by the information generation unit 32a of the compressor control device 3, or is executed in response to a user instruction. The pressure loss information is information recorded in the pressure loss information table 31a. The operating period allocation information is information recorded in the operating period allocation table 31c.

[0059] First, in step S11, the information generating unit 32a determines whether or not a pressure loss has occurred in each compressor 4. Next, in step S12, the information generating unit 32a generates pressure loss information from the determination result of step S11 as to whether or not a pressure loss has occurred. Specifically, the information generating unit 32a refers to the pressure loss determination table 31b based on the pressure measured by the pressure sensor 48, determines whether or not there is a suction pressure loss due to the outside air filter 46 of the outside air inlet 42, and sets a pressure loss flag in the "Presence or absence of pressure loss" column of the compressor 4 for which it has been determined that a pressure loss has occurred.

[0060] Next, in step S13, the information generation unit 32a generates operating period allocation information based on the pressure loss information generated in step S12. Specifically, the information generation unit 32a refers to the pressure loss information, and performs degeneration in accordance with the pressure loss for the operation of the compressor 4 in which a pressure loss is occurring ("reduce the mass by 2 / 3" of "degeneration" in the pressure loss determination table 31b) on the "operating period" of the corresponding compressor 4 in the operating period allocation table 31c. In other words, degenerate operation is performed to shorten the operating period of the compressor 4 in accordance with the pressure loss. The information generation unit 32a allocates the operating period reduced from the corresponding compressor 4 by degeneration from the operating period allocation table 31c to the operating periods of the other compressors 4.

[0061] <Driving pattern information generation process> 10 is a flowchart showing an operation pattern information generation process according to the first embodiment. The operation pattern information generation process is repeatedly executed at a predetermined cycle by the operation pattern information generation unit 32b of the compressor control device 3, or is executed in response to a user instruction. The operation pattern information is information recorded in the operation pattern table 31d.

[0062] First, in step S20, the operation pattern information generation unit 32b determines whether the pressure loss information (pressure loss information table 31a) has changed since the previous execution of the operation pattern information generation process. The pressure loss information is saved in a predetermined storage area each time the operation pattern information generation process is executed. If the pressure loss information has changed (step S20 YES), the operation pattern information generation unit 32b proceeds to step S21, and if the pressure loss information has not changed (step S20 NO), the operation pattern information generation process ends.

[0063] In step S21, the operation pattern information generation unit 32b reduces the "operating period (number of squares)" for each compressor 4 in accordance with the compression loss if a compression loss occurs in the compressor 4 in question, and allocates the reduced squares to the "operating periods (number of squares)" of the other compressors 4.

[0064] Next, in step S33, if the changed operation pattern information newly created in the processing of step S21 is more energy-efficient than the operation pattern information before the change, the operation pattern information generation unit 32b updates the pressure loss information table 31a with the changed operation pattern information. The energy of the operation pattern information before and after the change is calculated by integrating the power consumption characteristics when each compressor 4 (constant speed unit Fi and variable speed unit Vj) is operated at full load and under capacity control in accordance with the operation pattern. At this time, the decrease in rated power efficiency due to compression loss of each compressor 4 is taken into consideration. On the other hand, if the changed operation pattern information is more energy-efficient than the operation pattern information before the change, the operation pattern information generation unit 32b discards the changed operation pattern and maintains the operation pattern information before the change.

[0065] <Application example 1> Hereinafter, an example in which the compressor system 1 is configured with a total of four compressors (M=N=2), including two constant speed compressors and two variable speed compressors, will be described as Application Example 1 of Embodiment 1.

[0066] 11 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to Application Example 1 of Embodiment 1 (when a total of four compressors, two constant speed compressors and two variable speed compressors, are operating normally). As shown in (a) of FIG. 11, no compression loss occurs in any of the four compressors 4 constituting the compressor system 1.

[0067] Therefore, the operating period (number of cells) is allocated equally to the total of the two constant speed machines and the total of the two variable speed machines, at 20 / 2 = 10, and is also allocated equally within each of the constant speed machines and the variable speed machines, at 10 / 2 = 5, resulting in operating period allocation table 31c as shown in Figure 11(b). Based on the operating period allocation table 31c shown in Figure 11(b), operating pattern table 31d may be, for example, as shown in Figure 11(c). The operating pattern table 31d in Figure 11(c) is created in advance as default information prior to operation of the compressor system 1.

[0068] Next, a case where a pressure loss occurs in the variable speed device V1 will be described in Application Example 1. Fig. 12 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to Application Example 1 of Embodiment 1 (when a compression loss occurs in the variable speed device).

[0069] As shown in FIG. 12(a), assume that a compression loss occurs in variable speed unit V1, one of the four compressors 4 that make up compressor system 1. In this case, the operating period of variable speed unit V1 is degenerated to "reducing the mass by 2 / 3." Then, the allocation of the operating period to each compressor 4 other than variable speed unit V1 is rebalanced, and the degenerated amount of variable speed unit V1, "5 × (2 / 3) = 3 masses," is allocated to variable speed unit V2. Therefore, operating period allocation table 31c becomes as shown in FIG. 12(b). Furthermore, based on operating period allocation table 31c shown in FIG. 12(b), variable speed unit V2 in the capacity adjustment ranges where the air usage ratio is 0 to 100, 100 to 200, and 200 to 300 (%) is replaced with variable speed unit V2, and the operating pattern table 31d is updated, for example, as shown in FIG. 12(c).

[0070] In operation pattern tables 31d shown in (c) of Figures 11 and 12, variable speed units V1 and V2 are swapped when the air consumption ratio is 300-400 and 400-300% and the power consumption ratio is 200-300 and 300-400%. This is the case where operation pattern table 31d is updated to optimize the power efficiency of compressor system 1 as a whole, taking into account the decrease in rated power efficiency due to the compression loss of variable speed unit V1. However, even if variable speed units V1 and V2 are not swapped in (c) of Figure 12 and are kept the same as (c) of Figure 11, the objective of improving the power efficiency of compressor system 1 as a whole can be achieved, taking into account the decrease in rated power efficiency due to the compression loss of variable speed unit V1.

[0071] Next, a case where a pressure loss occurs in the constant speed machine F2 will be described in Application Example 1. Fig. 13 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to Application Example 1 of Embodiment 1 (when a compression loss occurs in the constant speed machine).

[0072] As shown in FIG. 13(a), assume that a compression loss occurs in constant speed compressor F2, one of the four compressors 4 that make up compressor system 1. In this case, the operating period of constant speed compressor F2 is degenerated to "reduce the mass by 2 / 3." Then, the allocation of the operating periods of each compressor 4 other than constant speed compressor F2 is rebalanced, and the degenerated amount of constant speed compressor F1, "5 × (2 / 3) = 3 masses," is evenly allocated to the other constant speed compressors and variable speed compressors. Therefore, the operating period allocation table 31c becomes as shown in FIG. 19(b). 19(b), in the operation pattern table 31d, the constant speed machine F2 in the full load range where the air consumption ratio is 200 to 300% is replaced with the variable speed machine V1, the variable speed machine V1 in the capacity adjustment range is replaced with the variable speed machine V2, and the constant speed machine F2 in the full load range where the air consumption ratio is 300 to 200% is replaced with the variable speed machine V1, and the constant speed machine F2 in the full load range where the air consumption ratio is 200 to 100% is replaced with the constant speed machine F1. Therefore, for example, the operation pattern table 31d becomes as shown in FIG. 13(c).

[0073] <Application example 2> Next, an example in which the compressor system 1 is configured with a total of three compressors (M=2, N=1), including two constant speed compressors and one variable speed compressor, will be described as Application Example 2 of Embodiment 1.

[0074] 14 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to application example 2 of embodiment 1 (when a total of three compressors, two constant speed compressors and one variable speed compressor, are operating normally). As shown in (a) of FIG. 14, no compression loss occurs in any of the three compressors 4 that make up compressor system 1.

[0075] Therefore, the operating period (number of cells) is allocated equally to the total of the two constant speed machines and the one variable speed machine, i.e., 12 / 2=6, and is also allocated equally within each of the constant speed machines and the variable speed machine, resulting in operating period allocation table 31c as shown in Figure 14(b). Based on operating period allocation table 31c shown in Figure 14(b), operating pattern table 31d becomes, for example, as shown in Figure 14(c). Operating pattern table 31d in Figure 14(c) is created in advance as default information prior to operation of compressor system 1.

[0076] Next, a case where a pressure loss occurs in the variable speed drive V1 in Application Example 2 of Embodiment 1 will be described. Fig. 15 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to Application Example 2 of Embodiment 1 (when a compression loss occurs in the variable speed drive).

[0077] As shown in FIG. 15(a), assume that a compression loss occurs in variable speed unit V1, one of the three compressors 4 that make up compressor system 1. In this case, the operating period of variable speed unit V1 is degenerated to "reduce the mass by 2 / 3." Then, the allocation of the operating period to each compressor 4 other than variable speed unit V1 is rebalanced, and the degenerated amount of variable speed unit V1, "6 × (2 / 3) = 4 masses," is evenly allocated to all other constant speed units. Therefore, operating period allocation table 31c becomes as shown in FIG. 15(b).

[0078] Furthermore, based on the operating period allocation table 31c shown in Figure 15(b), in the operating pattern table 31d, the variable speed machine V1 in the capacity adjustment ranges of the air usage ratio 0 to 100 and 100 to 200 (%) is replaced with the constant speed machines F1 and F2, respectively, and the variable speed machine V1 in the capacity adjustment ranges of 200 to 100 and 100 to 0 (%) is replaced with the constant speed machines F1 and F2, respectively. Therefore, for example, it becomes as shown in Figure 15(c).

[0079] Next, a case where a pressure loss occurs in the constant speed machine F2 will be described in Application Example 2. Fig. 16 is an explanatory diagram of generation of operation pattern information (operation pattern table 31d) according to Application Example 2 (when a compression loss occurs in the constant speed machine).

[0080] As shown in FIG. 16(a), assume that a compression loss occurs in constant speed unit F2, one of the three compressors 4 that make up compressor system 1. In this case, the operating period of constant speed unit F2 is degenerated to "reduce the mass by 2 / 3." Then, the allocation of the operating periods of each compressor 4 other than constant speed unit F2 is rebalanced, and the degenerated amount of constant speed unit F1, "3 × (2 / 3) = 2 masses," is evenly allocated to the other constant speed units. Therefore, operating period allocation table 31c becomes as shown in FIG. 16(b).

[0081] Furthermore, based on the operating period allocation table 31c shown in (b) of Figure 16, the operating pattern table 31d replaces the constant speed machine F2 in the full load range where the air usage ratio is 200 to 100 (%) with the constant speed machine F1, and becomes, for example, as shown in (c) of Figure 16.

[0082] <Displaying driving pattern information, etc. to the user> Fig. 17 is an explanatory diagram of a display screen 34a in the compressor control device 3 according to the first embodiment. As shown in Fig. 17, the compressor control device 3 outputs a display screen 34a from an output device that indicates changes made to the default information in the operation pattern table 31d (operation pattern information) such as those shown in Figs. 11 to 16, thereby enabling the user to intuitively understand which compressor 4 has generated pressure loss and which compressor 4 will be substituted. Furthermore, as shown in Fig. 17, the compressor control device 3 can also notify the user to perform maintenance by indicating the filter that is causing pressure loss in the compressor 4 that is not operating.

[0083] The display screen 34a may be output from the output device of the management device 2, not from the compressor control device 3.

[0084] [Embodiment 2] In the second embodiment, the compressor control device 3 is different in the operation pattern information generation process executed by the operation pattern information generation unit 32b, but is otherwise similar.

[0085] <Driving pattern generation process of embodiment 2> 18 is a flowchart showing an operation pattern information generation process according to the second embodiment. The operation pattern information generation process according to the second embodiment is repeatedly executed at a predetermined cycle by the operation pattern information generation unit 32b of the compressor control device 3, or is executed in response to a user instruction. The operation pattern information is information recorded in the operation pattern table 31d.

[0086] First, in step S20, the operation pattern information generation unit 32b determines whether the pressure loss information (pressure loss information table 31a) has changed since the previous execution of the operation pattern information generation process, or whether this is the first execution of the operation pattern information generation process. If the pressure loss information has changed or this is the first execution (step S21 YES), the operation pattern information generation unit 32b proceeds to step S22, and if the pressure loss information has not changed (step S21 NO), the operation pattern information generation process ends.

[0087] In step S22, the driving pattern information generating unit 32b initializes a counter variable D to D=0.

[0088] Next, in step S23, the driving pattern information generating unit 32b initializes a counter variable d to d=0, and adds 1 to a counter variable D.

[0089] Next, in step S24, the operation pattern information generator 32b executes a process of "selecting a compressor to be operated at full load from among all constant speed machines." Details of the process of "selecting a compressor to be operated at full load from among all constant speed machines" will be described later with reference to FIG. 19.

[0090] Next, in step S25, the operation pattern information generating unit 32b executes a process of "selecting a compressor to be operated at full load from among variable speed machines without pressure loss." Details of the process of "selecting a compressor to be operated at full load from among variable speed machines without pressure loss" will be described later with reference to FIG. 20.

[0091] Next, in step S26, the operation pattern information generator 32b executes a process of "selecting a compressor to be operated by capacity control from among variable speed machines without pressure loss." Details of the process of "selecting a compressor to be operated by capacity control from among variable speed machines without pressure loss" will be described later with reference to FIG.

[0092] Next, in step S27, the operation pattern information generator 32b executes a process of "selecting a compressor to perform capacity control operation from among constant speed compressors without pressure loss." Details of the process of "selecting a compressor to perform capacity control operation from among constant speed compressors without pressure loss" will be described later with reference to FIG.

[0093] Next, in step S28, the operation pattern information generator 32b executes a process of "selecting a compressor to be operated by capacity control from among variable speed machines with pressure loss." Details of the process of "selecting a compressor to be operated by capacity control from among variable speed machines with pressure loss" will be described later with reference to FIG.

[0094] Next, in step S29, the operation pattern information generator 32b executes a process of "selecting a compressor to be operated by capacity control from among constant speed machines with pressure loss." Details of the process of "selecting a compressor to be operated by capacity control from among constant speed machines with pressure loss" will be described later with reference to FIG.

[0095] Next, in step S30, the driving pattern information generation unit 32b determines whether the counter variable D=M+N (M is the total number of constant speed machines, and N is the total number of variable speed machines). If the counter variable D=M+N (step S30 YES), the driving pattern information generation unit 32b proceeds to step S31, and if the counter variable D≠M+N (step S30 NO), the driving pattern information generation unit 32b returns to step S31.

[0096] In step S31, the operation pattern information generation unit 32b copies the operation pattern information for d=1 to (M+N) generated by repeating steps S23 to S30 in reverse order of d. To explain this in detail using the example in Fig. 8, the operation pattern information for air consumption ratios of 0 to 100 (d=1), 100 to 200 (d=2), 200 to 300 (d=3), . . ., (M+N-1) x 100 to (M+N) x 100 (d=M+N) (%) is copied to the right of the symmetrical axis in reverse order of d, with the air consumption ratio = (M+N) x 100 (%) as the symmetrical axis.

[0097] Next, in step S32, the operation pattern information generation unit 32b averages the operation periods of each compressor 4 based on the information in the operation period allocation table 31c. Specifically, using the example in FIG. 8 as a specific example, simply copying the operation pattern information to the right of the symmetry axis, with the air consumption ratio = (M + N) × 100 (%) as the axis of symmetry, in reverse order of d, will result in differences between the operation periods of the constant speed units Fi and the variable speed units Vj in the operation pattern table 31d and the operation periods shown in the operation period allocation table 31c. The operation pattern information generation unit 32b interchanges the operation periods of the constant speed units Fi and the variable speed units Vj to make the operation periods in the operation pattern table 31d and the operation period allocation table 31c the same.

[0098] Next, in step S33, if the changed operation pattern information newly created in the process of step S32 is more energy-saving than the operation pattern information before the change, the operation pattern information generation unit 32b updates the pressure loss information table 31a with the changed operation pattern information. On the other hand, if the changed operation pattern information is energy-consuming compared with the operation pattern information before the change, the operation pattern information generation unit 32b discards the changed operation pattern and maintains the operation pattern information before the change.

[0099] FIG. 19 is a detailed flow of step S24 in the operation pattern information generation process of FIG. 18. First, in step S24a, the operation pattern information generation unit 32b sets the counter variable i = 1. Next, in step S24b, the operation pattern information generation unit 32b determines whether the counter variable D≠1 and d<D-1. When the counter variable D≠1 and d<D-1 (step S24b YES), the operation pattern information generation unit 32b transfers the process to step S24c, and when the counter variable D = 1 or d≧D (step S24b NO), the operation pattern information generation unit 32b transfers the process to step S25 (FIG. 18).

[0100] In step S24c, the operation pattern information generation unit 32b refers to the pressure loss information table 31a and determines whether the constant speed machine Fi has no pressure loss. When the constant speed machine Fi has no pressure loss (step S24c YES), the operation pattern information generation unit 32b transfers the process to step S24d, and when the constant speed machine Fi has pressure loss (step S24c NO), the operation pattern information generation unit 32b transfers the process to step S24f.

[0101] In step S24d, the operation pattern information generation unit 32b sets full load operation for the constant speed machine Fi in the operation pattern table 31d.

[0102] In one step S24f, the driving pattern information generation unit 32b adds 1 to the counter variable i. Next, in step S24g, the driving pattern information generation unit 32b determines whether i > M (M is the total number of constant speed machines Fi). If i > M (step S24g YES), the driving pattern information generation unit 32b transfers the process to step S24h. If i ≤ M (step S24g NO), the driving pattern information generation unit 32b transfers the process to step S24b.

[0103] In step S24h, the driving pattern information generation unit 32b determines whether d < D - N. If d < D - N (step S24h YES), the driving pattern information generation unit 32b transfers the process to step S24i. If d ≥ D - N (step S24h NO), the driving pattern information generation unit 32b transfers the process to step S25 (FIG. 18).

[0104] In step S24i, the driving pattern information generation unit 32b sets the counter variable i = 1. Next, in step S24j, the driving pattern information generation unit 32b determines whether the counter variable D ≠ 1 and d < D - 1. If the counter variable D ≠ 1 and d < D - 1 (step S24j YES), the driving pattern information generation unit 32b transfers the process to step S24k. If the counter variable D = 1 or d ≥ D (step S24j NO), the driving pattern information generation unit 32b transfers the process to step S25 (FIG. 18).

[0105] In step S24k, the driving pattern information generation unit 32b refers to the pressure loss information table 31a and determines whether the constant speed machine Fi has a pressure loss. If the constant speed machine Fi has a pressure loss (step S24k YES), the driving pattern information generation unit 32b transfers the process to step S24l. If the constant speed machine Fi has no pressure loss (step S24k NO), the driving pattern information generation unit 32b transfers the process to step S24n.

[0106] In step S24l, the driving pattern information generation unit 32b sets a full load operation for the constant speed machine Fi in the driving pattern table 31d.

[0107] In one step S24n, the operation pattern information generation unit 32b adds 1 to the counter variable i. Next, in step S24o, the operation pattern information generation unit 32b determines whether i > M (M is the total number of constant speed machines Fi). When i > M (step S24o YES), the operation pattern information generation unit 32b transfers the process to step S25 (FIG. 18), and when i ≤ M (step S24o NO), the operation pattern information generation unit 32b transfers the process to step S24j.

[0108] FIG. 20 is a detailed flow of step S25 of the operation pattern information generation process in FIG. 18. First, in step S25a, the operation pattern information generation unit 32b sets the counter variable j = 1. Next, in step S25b, the operation pattern information generation unit 32b determines whether the counter variable D ≠ 1 and d < D - 1. When the counter variable D ≠ 1 and d < D - 1 (step S25b YES), the operation pattern information generation unit 32b transfers the process to step S25c, and when the counter variable D = 1 or d ≥ D (step S25b NO), the operation pattern information generation unit 32b transfers the process to step S26 (FIG. 18).

[0109] In step S25c, the operation pattern information generation unit 32b refers to the pressure loss information table 31a and determines whether the variable speed machine Vj has no pressure loss. When the variable speed machine Vj has no pressure loss (step S25c YES), the operation pattern information generation unit 32b transfers the process to step S25d, and when the variable speed machine Vj has pressure loss (step S25c NO), the operation pattern information generation unit 32b transfers the process to step S25f.

[0110] In step S25d, the operation pattern information generation unit 32b sets full load operation for the variable speed machine Vj in the operation pattern table 31d.

[0111] In one step S25f, the driving pattern information generation unit 32b adds 1 to the counter variable j. Next, in step S25g, the driving pattern information generation unit 32b determines whether j > N (N is the total number of the variable speed machines Vj). When j > N (step S25g YES), the driving pattern information generation unit 32b transfers the process to step S26 (FIG. 18), and when j ≤ N (step S25g NO), the driving pattern information generation unit 32b transfers the process to step S25b.

[0112] FIG. 21 is a detailed flow of step S26 of the driving pattern information generation process in FIG. 18. First, in step S26a, the driving pattern information generation unit 32b sets the counter variable j = 1. Next, in step S26b, the driving pattern information generation unit 32b determines whether the counter variable d = D. When the counter variable d = D (step S26b YES), the driving pattern information generation unit 32b transfers the process to step S26c, and when the counter variable d ≠ D (step S26b NO), the driving pattern information generation unit 32b transfers the process to step S26f.

[0113] In step S26c, the driving pattern information generation unit 32b determines whether the variable speed machine Vj has no pressure loss and whether the operation has already been set at d < D - 1 (step S25d in FIG. 20 has been executed). When the variable speed machine Vj has no pressure loss and the operation has not already been set (step S26c YES), the driving pattern information generation unit 32b transfers the process to step S26d, and when the variable speed machine Vj has pressure loss or the operation has already been set (step S26c NO), the driving pattern information generation unit 32b transfers the process to step S26f.

[0114] In step S26d, the driving pattern information generation unit 32b sets the capacity control operation for the variable speed machine Vj. Next, in step S26e, the driving pattern information generation unit 32b adds 1 to the counter variable d.

[0115] On the other hand, in step S26f, the driving pattern information generation unit 32b adds 1 to the counter variable j. Next, in step S26g, the driving pattern information generation unit 32b determines whether j>N (N is the total number of variable speed units Vj). If j>N (step S26gYES), the driving pattern information generation unit 32b transfers the process to step S27 (FIG. 18), and if j≦N (step S26gNO), the driving pattern information generation unit 32b transfers the process to step S26b.

[0116] Figure 22 is a detailed flow of step S27 of the driving pattern information generation process of Figure 18. First, in step S27a, the driving pattern information generation unit 32b sets the counter variable i = 1. Next, in step S27b, the driving pattern information generation unit 32b determines whether the counter variable d = D-1. If the counter variable d = D-1 (step S27b YES), the driving pattern information generation unit 32b proceeds to step S27c, and if the counter variable d ≠ D-1 (step S27b NO), the driving pattern information generation unit 32b proceeds to step S28 (Figure 10).

[0117] In step S27c, the operation pattern information generation unit 32b determines whether the constant speed machine Fi has no pressure loss and has already been set to operate (steps S24d and S24l in FIG. 19 have been executed). If the constant speed machine Fi has no pressure loss and has not already been set to operate (step S27c YES), the operation pattern information generation unit 32b proceeds to step S27d, and if the variable speed machine Vj has a pressure loss or has already been set to operate (step S27c NO), the operation pattern information generation unit 32b proceeds to step S27f.

[0118] In step S27d, the operation pattern information generating unit 32b sets the capacity control operation for the constant speed machine Fi. Next, in step S27e, the operation pattern information generating unit 32b adds 1 to the counter variable d.

[0119] On the other hand, in step S27f, the driving pattern information generation unit 32b adds 1 to the counter variable i. Next, in step S27g, the driving pattern information generation unit 32b determines whether i>M (M is the total number of constant speed machines Fi). If i>M (step S27gYES), the driving pattern information generation unit 32b proceeds to step S28 (FIG. 18), and if i≦M (step S27gNO), the driving pattern information generation unit 32b proceeds to step S27b.

[0120] Figure 23 is a detailed flow of step S28 of the driving pattern information generation process of Figure 18. First, in step S28a, the driving pattern information generation unit 32b sets counter variable j = 1. Next, in step S28b, the driving pattern information generation unit 32b determines whether counter variable d = D-1. If counter variable d = D-1 (step S28b YES), the driving pattern information generation unit 32b proceeds to step S28c, and if counter variable d ≠ D-1 (step S28b NO), the driving pattern information generation unit 32b proceeds to step S29 (Figure 18).

[0121] In step S28c, the operation pattern information generation unit 32b determines whether the variable speed machine Vj has a pressure loss. If the variable speed machine Vj has a pressure loss (step S28c YES), the operation pattern information generation unit 32b proceeds to step S28d, and if the variable speed machine Vj has no pressure loss (step S28c NO), the operation pattern information generation unit 32b proceeds to step S28f.

[0122] In step S28d, the driving pattern information generating unit 32b sets the variable speed machine Vj to a displacement control operation. Next, in step S28e, the driving pattern information generating unit 32b adds 1 to the counter variable d.

[0123] On the other hand, in step S28f, the driving pattern information generation unit 32b adds 1 to the counter variable j. Next, in step S28g, the driving pattern information generation unit 32b determines whether j>N (N is the total number of variable speed units Vj). If j>N (step S28gYES), the driving pattern information generation unit 32b proceeds to step S29 (FIG. 10), and if j≦N (step S28gNO), the driving pattern information generation unit 32b proceeds to step S28b.

[0124] Figure 24 is a detailed flow of step S29 of the driving pattern information generation process of Figure 18. First, in step S29a, the driving pattern information generation unit 32b sets the counter variable i = 1. Next, in step S29b, the driving pattern information generation unit 32b determines whether the counter variable d = D-1. If the counter variable d = D-1 (step S29b YES), the driving pattern information generation unit 32b proceeds to step S29c, and if the counter variable d ≠ D-1 (step S29b NO), the driving pattern information generation unit 32b proceeds to step S30 (Figure 18).

[0125] In step S29c, the operation pattern information generation unit 32b determines whether the constant speed machine Fi has a pressure loss and the operation has already been set (steps S24d and S241 in FIG. 19 and step S27d in FIG. 22 have been executed). If the constant speed machine Fi has a pressure loss and the operation has not already been set (step S29c YES), the operation pattern information generation unit 32b proceeds to step S29d, and if the constant speed machine Fi has no pressure loss or the operation has already been set (step S29c NO), the operation pattern information generation unit 32b proceeds to step S29f.

[0126] In step S29d, the operation pattern information generating unit 32b sets the capacity control operation for the constant speed machine Fi. Next, in step S29e, the operation pattern information generating unit 32b adds 1 to the counter variable d.

[0127] On the other hand, in step S29f, the driving pattern information generation unit 32b adds 1 to the counter variable i. Next, in step S29g, the driving pattern information generation unit 32b determines whether i>M (M is the total number of constant speed machines Fi). If i>M (step S29gYES), the driving pattern information generation unit 32b proceeds to step S30 (FIG. 10), and if i≦M (step S29gNO), the driving pattern information generation unit 32b proceeds to step S29b.

[0128] In this embodiment, the execution order of steps S24 to S29 in FIG. 18 can be changed as appropriate by comparing the power efficiency of each pattern: full load operation of a constant speed machine without pressure loss, capacity control operation of a constant speed machine without pressure loss, full load operation of a constant speed machine with pressure loss, capacity control operation of a constant speed machine with pressure loss, full load operation of a variable speed machine without pressure loss, capacity control operation of a variable speed machine without pressure loss, full load operation of a variable speed machine with pressure loss, and capacity control operation of a variable speed machine with pressure loss.The order can be changed as appropriate so that the compressor 4 with the better power efficiency is operated preferentially and the operation of the compressor 4 with the lower power efficiency is restricted.

[0129] <Effects of the embodiment> In the above-described embodiment, among the multiple compressors 4, operation of a compressor with a higher power efficiency according to the detected physical quantity is given priority, and operation of a compressor with a lower power efficiency is restricted. Therefore, in a compressor system 1 in which multiple compressors 4 are operated in turn according to the load, a decrease in the power efficiency of the entire compressor system 1 can be suppressed by shortening the operating period of a compressor 4 in which a pressure loss is occurring or by operating it at a low rotation speed.

[0130] Furthermore, in the above-described embodiment, by controlling the operation of multiple compressors 4 so as to optimize the power efficiency of the entire compressor system 1, it is possible to minimize the decrease in the power efficiency of the entire compressor system 1 even in situations where pressure loss occurs in some of the compressors 4.

[0131] Furthermore, in the above-described embodiment, the multiple compressors 4 include a variable speed machine Vj that can variably control the speed of the compressor main body 45, and a constant speed machine Fi that controls the compressor main body 45 at a constant speed. Therefore, even in a compressor system 1 that mixes variable speed machines Vj and constant speed machines Fi, it is possible to suppress a decrease in the power efficiency of the entire compressor system 1 due to pressure loss.

[0132] In the above-described embodiment, the filter includes at least one of various filters provided at each of a plurality of locations. The various filters include an outside air filter 46 that filters air passing through the outside air inlet, an intake air filter 47 that filters air taken in from the intake portion of the compressor main body 45, and a separator element that filters compressed air discharged from each compressor 4. The suction pressure loss due to the filter is the pressure loss due to the outside air filter 46, the pressure loss due to the intake air filter 47, or the pressure loss due to the separator element. Therefore, a decrease in the power efficiency of the entire compressor system 1 can be suppressed due to pressure loss caused by clogging of any filter.

[0133] Furthermore, in the above-described embodiment, the power efficiency according to the detected physical quantity is the power efficiency obtained by subtracting the efficiency reduction caused by the suction pressure loss due to the filter from the rated power efficiency of each compressor 4. Therefore, the compressor 4 with the best power efficiency taking the pressure loss into consideration is preferentially operated, so that the reduction in the power efficiency of the entire compressor system 1 caused by the pressure loss can be suppressed.

[0134] Furthermore, in the above-described embodiment, the pressure loss due to the outside air filter 46 is determined based on the pressure of the air after passing through the outside air filter 46 and the outside air inlet 42, the pressure loss due to the intake air filter 47 is determined based on the temperature of the air taken in from the intake section of the compressor main body 45, and the pressure loss due to the separator element is determined based on the discharge pressure of the air compressed by each compressor 4 and the pressure in the air tank 5 where the air joins. Therefore, it is possible to appropriately suppress a decrease in the power efficiency of the entire compressor system 1 with respect to the pressure loss of each filter that is appropriately determined using the detection value of the sensor corresponding to each filter.

[0135] Furthermore, in the above-described embodiment, the greater the efficiency reduction caused by the suction pressure loss due to the filter, the greater the restriction on operation of the compressor with a lower power efficiency according to the detected physical quantity. Therefore, compressors 4 with a greater efficiency reduction are excluded from operation as much as possible, thereby further suppressing the reduction in power efficiency of the entire compressor system 1 due to pressure loss.

[0136] Furthermore, in the above-described embodiment, the operation restriction on the compressor 4 includes stopping the operation and reducing the operation of the compressor 4. Therefore, the compressor 4 with a large efficiency drop is stopped if it can be stopped, and is operated only when it is unavoidable to operate, so that it is possible to highly achieve both the desired air usage ratio and suppress a drop in the power efficiency of the entire compressor system 1 due to pressure loss.

[0137] In addition, in the above-described embodiment, by notifying the user of the compressor system 1 to prompt maintenance of the filter of the compressor 4 that is not operating, the user can be sure to perform filter maintenance efficiently at the optimal timing.

[0138] Furthermore, in the above-described embodiment, among the multiple compressors 4, the compressor 4 with the higher power efficiency according to the detected pressure is preferentially operated, and if restricting the operation of the compressors 4 with the lower power efficiency would reduce the power efficiency of the entire compressor system 1, the compressors 4 with the higher power efficiency and the compressors 4 with the lower power efficiency are not operated or restricted from operating. Therefore, it is possible to prevent the inconvenience of reducing the power efficiency of the entire compressor system 1 by operating or restricting the operation of the compressors 4.

[0139] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, replace, integrate, or distribute part of the configuration of each embodiment with other configurations. Furthermore, each process shown in the embodiments may be appropriately distributed or integrated based on processing efficiency or implementation efficiency. [Explanation of symbols]

[0140] 1: compressor system, 2: management device, 3: compressor control device, 4: compressor, Fi: constant speed machine, Fj: variable speed machine

Claims

1. A compressor system having a plurality of compressors and a compressor control device that controls operation of the plurality of compressors, Each of the compressors is A filter for filtering the air, a compressor body that compresses air; a detection means for detecting a physical quantity correlated with the pressure loss of the compressor body, The plurality of compressors include a constant speed compressor that controls the compressor main body at a constant speed to keep the amount of compressed air produced constant, and a variable speed compressor that controls the compressor main body at a variable speed to increase or decrease the amount of compressed air produced, The constant speed machine performs a full load operation in which the amount of compressed air produced is kept constant by constantly repeating periods of loading and unloading at a constant rotation speed of a motor provided in the constant speed machine, and a capacity control operation in which the amount of compressed air produced is increased or decreased by adjusting and repeating periods of loading and unloading at a constant rotation speed of the motor, the variable speed machine performs a full load operation in which the rotation speed of a motor provided in the variable speed machine is set at full load to keep the amount of compressed air produced constant, and a capacity control operation in which the rotation speed of the motor is adjusted to increase or decrease the amount of compressed air produced, The physical quantity is any one of a suction pressure of the filter, a temperature around an intake part of the compressor, and an intake temperature of the compressor, The compressor control device includes: When determining which of the plurality of compressors is to perform the full load operation and which is to perform the capacity control operation, in order to preferentially operate a compressor having a higher power efficiency according to any one of the suction pressure of the filter detected by the detection means, the temperature around the intake part of the compressor, and the intake temperature of the compressor, and to restrict operation of a compressor having a lower power efficiency, selecting, from among all of the plurality of compressors, a compressor to be operated at full load in the order of priority, the constant speed compressor having a power efficiency equal to or greater than a certain level according to the physical quantity detected by the detection means, the variable speed compressor having a power efficiency equal to or greater than the certain level, and the constant speed compressor having a power efficiency less than the certain level; After the compressor to be operated at full load is selected, a compressor to be operated at full load is selected from among the plurality of compressors not selected as compressors to be operated at full load in the order of priority: the variable speed compressor having a power efficiency equal to or greater than a certain level, the constant speed compressor having a power efficiency equal to or greater than a certain level, the variable speed compressor having a power efficiency less than a certain level, and the constant speed compressor having a power efficiency less than a certain level. A compressor system comprising:

2. 2. The compressor system of claim 1, The compressor control device includes: Controlling the operation of the plurality of compressors so as to maximize the power efficiency of the entire compressor system A compressor system comprising:

3. 2. The compressor system of claim 1, In each of the compressors, The filter includes at least one of various filters provided at each of a plurality of locations. A compressor system comprising:

4. 4. The compressor system of claim 3, The filters include an outside air filter that filters air passing through an outside air inlet, an intake air filter that filters air taken in from an intake portion of the compressor main body, and a separator element that filters compressed air discharged from each compressor. A compressor system comprising:

5. 5. The compressor system of claim 4, The power efficiency corresponding to the physical quantity detected by the detecting means is the power efficiency obtained by subtracting the efficiency reduction caused by the suction pressure loss due to the filter from the rated power efficiency of each compressor. A compressor system comprising:

6. 6. The compressor system of claim 5, The suction pressure loss due to the filter is the pressure loss due to the outside air filter, the pressure loss due to the intake air filter, or the pressure loss due to the separator element. A compressor system comprising:

7. 7. The compressor system of claim 6, The pressure loss due to the outside air filter is determined based on the pressure of air after passing through the outside air filter and the outside air inlet, The pressure loss caused by the intake filter is determined based on the temperature of air taken in from an intake portion of the compressor body, The pressure loss due to the separator element is determined based on the discharge pressure of the air compressed by each compressor and the pressure in the air tank where the air joins. A compressor system comprising:

8. 6. The compressor system of claim 5, The greater the decrease in efficiency caused by the suction pressure loss due to the filter, the greater the restriction on operation of the compressor having a lower power efficiency according to the physical quantity detected by the detection means. A compressor system comprising:

9. 2. The compressor system of claim 1, The restriction on the operation of the compressor includes stopping the operation of the compressor and reducing the operation of the compressor. A compressor system comprising:

10. 2. The compressor system of claim 1, A user of the compressor system is notified to perform maintenance on the filter of the compressor that is currently out of operation. A compressor system comprising:

11. 2. The compressor system of claim 1, The compressor control device includes: Among the plurality of compressors, a compressor having a higher power efficiency according to the pressure detected by the detection means is preferentially operated, and if restricting the operation of a compressor having a lower power efficiency would result in a decrease in the power efficiency of the entire compressor system, the operation of the compressor having the higher power efficiency and the operation of the compressor having the lower power efficiency are not restricted. A compressor system comprising:

12. A compressor control device that controls operation of a plurality of compressors in a compressor system, Each of the compressors is A filter for filtering the air, a compressor body that compresses air; a detection means for detecting a physical quantity correlated with the pressure loss of the compressor body, The plurality of compressors include a constant speed compressor that controls the compressor main body at a constant speed to keep the amount of compressed air produced constant, and a variable speed compressor that controls the compressor main body at a variable speed to increase or decrease the amount of compressed air produced, The constant speed machine performs a full load operation in which the amount of compressed air produced is kept constant by constantly repeating periods of loading and unloading at a constant rotation speed of a motor provided in the constant speed machine, and a capacity control operation in which the amount of compressed air produced is increased or decreased by adjusting and repeating periods of loading and unloading at a constant rotation speed of the motor, the variable speed machine performs a full load operation in which the rotation speed of a motor provided in the variable speed machine is set at full load to keep the amount of compressed air produced constant, and a capacity control operation in which the rotation speed of the motor is adjusted to increase or decrease the amount of compressed air produced, The physical quantity is any one of a suction pressure of the filter, a temperature around an intake part of the compressor, and an intake temperature of the compressor, When determining which of the plurality of compressors is to perform the full load operation and which is to perform the capacity control operation, in order to preferentially operate a compressor having a higher power efficiency according to any one of the suction pressure of the filter detected by the detection means, the temperature around the intake part of the compressor, and the intake temperature of the compressor, and to restrict operation of a compressor having a lower power efficiency, selecting, from among all of the plurality of compressors, a compressor to be operated at full load in the order of priority, the constant speed compressor having a power efficiency equal to or greater than a certain level according to the physical quantity detected by the detection means, the variable speed compressor having a power efficiency equal to or greater than the certain level, and the constant speed compressor having a power efficiency less than the certain level; After the compressor to be operated at full load is selected, a compressor to be operated at full load is selected from among the plurality of compressors not selected as compressors to be operated at full load in the order of priority: the variable speed compressor having a power efficiency equal to or greater than a certain level, the constant speed compressor having a power efficiency equal to or greater than a certain level, the variable speed compressor having a power efficiency less than a certain level, and the constant speed compressor having a power efficiency less than a certain level. A compressor control device characterized by:

13. A compressor control method performed by a compressor control device in a compressor system having a plurality of compressors and a compressor control device that controls operation of the plurality of compressors, comprising: Each of the compressors is A filter for filtering the air, a compressor body that compresses the air; a detection means for detecting a physical quantity correlated with the pressure loss of the compressor body, The plurality of compressors include a constant speed compressor that controls the compressor main body at a constant speed to keep the amount of compressed air produced constant, and a variable speed compressor that controls the compressor main body at a variable speed to increase or decrease the amount of compressed air produced, The constant speed machine performs a full load operation in which the amount of compressed air produced is kept constant by constantly repeating periods of loading and unloading at a constant rotation speed of a motor provided in the constant speed machine, and a capacity control operation in which the amount of compressed air produced is increased or decreased by adjusting and repeating periods of loading and unloading at a constant rotation speed of the motor, the variable speed machine performs a full load operation in which the rotation speed of a motor provided in the variable speed machine is set at full load to keep the amount of compressed air produced constant, and a capacity control operation in which the rotation speed of the motor is adjusted to increase or decrease the amount of compressed air produced, The physical quantity is any one of a suction pressure of the filter, a temperature around an intake part of the compressor, and an intake temperature of the compressor, The compressor control device, When determining which of the plurality of compressors is to perform the full load operation and which is to perform the capacity control operation, in order to preferentially operate a compressor having a higher power efficiency according to any one of the suction pressure of the filter detected by the detection means, the temperature around the intake part of the compressor, and the intake temperature of the compressor, and to restrict operation of a compressor having a lower power efficiency, selecting, from among all of the plurality of compressors, a compressor to be operated at full load in the order of priority, the constant speed compressor having a power efficiency equal to or greater than a certain level according to the physical quantity detected by the detection means, the variable speed compressor having a power efficiency equal to or greater than the certain level, and the constant speed compressor having a power efficiency less than the certain level; After the compressor to be operated at full load is selected, a compressor to be operated at full load is selected from among the plurality of compressors not selected as compressors to be operated at full load in the order of priority: the variable speed compressor having a power efficiency equal to or greater than a certain level, the constant speed compressor having a power efficiency equal to or greater than a certain level, the variable speed compressor having a power efficiency less than a certain level, and the constant speed compressor having a power efficiency less than a certain level. A compressor control method comprising:

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