Adjusting system of compressor and ship

Abstract

The utility model provides an adjusting system of a compressor and a ship, the compressor is arranged on a fuel supply pipeline, and a variable frequency motor of the adjusting system of the compressor is connected with the compressor and used for providing driving force for the compressor; the variable-frequency adjusting part is connected with the variable-frequency motor and used for adjusting the rotating speed of the variable-frequency motor so as to keep the pressure of the outlet end of the compressor constant; the pressure detection component is arranged on the fuel supply pipeline and used for detecting the pressure of the outlet end of the compressor and generating a pressure signal. The controller is connected with the variable frequency adjusting component and the pressure detection component and used for receiving a pressure signal, detected by the pressure detection component, of the outlet end of the compressor and controlling the variable frequency adjusting component to adjust the rotating speed of the variable frequency motor, and therefore the compressor adjusts the fuel compression amount. And stable control over the pressure of the outlet end of the compressor is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of compressors, in particular to a compressor regulating system and a ship. Background Art

[0002] In the process of compressing and transporting gas, the compressor may experience unstable pressure at the outlet due to fluctuations in operating conditions or gas demand, which poses a challenge to the stable control of the compressor. For example, dual-fuel powered ships are new ships that use both LNG and diesel as propulsion power. The ship starts the dual-fuel mode during navigation, using natural gas and diesel as fuel. Compared with traditional ships that use diesel alone as power, it has the characteristics of low carbon and environmental protection, low operating costs, and high safety factors. Therefore, using liquefied natural gas as ship fuel is a way for the shipping industry to reduce costs and be safe and environmentally friendly. During operation, the ship will adjust the fuel mode according to the situation. During the process of adjusting the fuel mode, the operating conditions of the compressor fluctuate greatly. When LNG fuel is switched to diesel fuel, the main engine no longer needs liquefied natural gas volatile gas, and the pressure at the outlet of the compressor rises sharply; when the main engine is switched from diesel fuel to LNG fuel, a large amount of liquefied natural gas volatile gas is pumped in for a short time when the main engine is started. During this switching process, there are great challenges in controlling the compressor that provides liquefied natural gas volatile gas. Utility Model Content

[0003] The purpose of the embodiments of the utility model is to provide a compressor adjustment system and a ship, so as to solve the problem in the prior art that the outlet pressure of the compressor cannot be stably controlled due to changes in working conditions.

[0004] The embodiment of the utility model adopts the following technical solution: a compressor adjustment system, the compressor is arranged on a fuel supply pipeline, and the adjustment system comprises:

[0005] A variable frequency motor connected to the compressor and used to provide driving force for the compressor;

[0006] A frequency conversion adjustment component, which is connected to the frequency conversion motor and is used to adjust the speed of the frequency conversion motor, thereby keeping the pressure at the outlet of the compressor constant;

[0007] A pressure detection component, which is arranged on the fuel supply pipeline and is used to detect the pressure at the outlet end of the compressor and generate a pressure signal;

[0008] A controller is connected to the frequency conversion regulating component and the pressure detecting component respectively, and is used to receive the pressure signal of the outlet end of the compressor detected by the pressure detecting component, and control the frequency conversion regulating component to adjust the rotation speed of the frequency conversion motor.

[0009] In some embodiments, the variable frequency adjustment component includes a frequency converter, the frequency converter is connected to the variable frequency motor and is used to adjust the speed of the variable frequency motor, and the variable frequency motor and the frequency converter are both connected to the controller;

[0010] When the pressure detection component detects that the pressure at the outlet of the compressor is greater than the set pressure, the pressure detection component sends a first detection signal to the controller; after receiving the first detection signal, the controller sends a first control signal to the frequency converter, and the frequency converter adjusts the variable frequency motor to reduce its speed to reduce the pressure at the outlet of the compressor, so that the pressure at the outlet of the compressor remains constant.

[0011] In some embodiments, the variable frequency motor is also connected to the controller to send the current signal of the variable frequency motor to the controller; the frequency converter is also connected to the power supply device of the variable frequency motor, and when the current signal of the variable frequency motor received by the controller exceeds the set value, the controller sends a second control signal to the frequency converter; after receiving the second control signal, the frequency converter sends a power-off signal to the power supply device to cut off the power supply to the variable frequency motor.

[0012] In some embodiments, the compressor regulation system also includes a bypass return mechanism, which is arranged on the fuel supply pipeline and is used to transport the fuel at the outlet end of the compressor back to the inlet end of the compressor to keep the pressure at the outlet end of the compressor constant.

[0013] In some embodiments, the controller is also connected to the bypass reflux mechanism, and the controller is used to control the opening of the bypass reflux mechanism, thereby keeping the pressure at the outlet end of the compressor constant.

[0014] In some embodiments, the controller is further configured to send a third control signal to the bypass reflux mechanism after receiving the first detection signal, so as to increase the opening of the bypass reflux mechanism and keep the pressure at the outlet of the compressor constant;

[0015] The controller is also used to send a fourth control signal to the bypass reflux mechanism after receiving the second detection signal, so as to reduce the opening of the bypass reflux mechanism and keep the pressure at the outlet end of the compressor constant.

[0016] In some embodiments, the bypass return mechanism includes a bypass return line and a bypass return valve, the bypass return valve is arranged on the bypass return line, one end of the bypass return line is connected to the inlet end of the compressor, and the other end of the bypass return line is connected to the outlet end of the compressor.

[0017] In some embodiments, the pressure detection component includes a pressure transmitter, and the pressure transmitter is connected to the fuel supply pipeline via a connecting pipeline, and a first valve and a second valve are arranged in parallel on the connecting pipeline.

[0018] An embodiment of the utility model further provides a ship, comprising a compressor, and the ship further comprises a regulating system for the compressor as described in any one of the above embodiments.

[0019] The beneficial effects of the embodiments of the utility model are:

[0020] A pressure detection component is set on the fuel supply pipeline to detect the pressure at the outlet of the compressor, and the pressure signal is transmitted to the controller. After receiving the pressure signal, the controller controls the frequency conversion adjustment component to adjust the speed of the frequency conversion motor, thereby adjusting the compression amount of the fuel by the compressor and achieving stable control of the pressure at the outlet of the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or related technologies, the drawings required for use in the embodiments or related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 It is a structural schematic diagram of the regulating system of the compressor of the utility model.

[0023] Figure numerals: 1. compressor; 2. variable frequency motor; 3. frequency converter; 4. bypass return valve; 5. pressure transmitter; 6. fuel supply pipeline. DETAILED DESCRIPTION

[0024] Various aspects and features of the present application are described herein with reference to the accompanying drawings.

[0025] It should be understood that various modifications may be made to the embodiments of the present application. Therefore, the above description should not be considered as limiting, but only as an example of an embodiment. Other modifications within the scope and spirit of the present application will occur to those skilled in the art.

[0026] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and, together with the general description of the present application given above and the detailed description of the embodiments given below, serve to explain the principles of the present application.

[0027] These and other characteristics of the present application will become apparent from the following description of a preferred form of embodiment given as a non-limiting example with reference to the accompanying drawings.

[0028] It should also be understood that although the present application has been described with reference to some specific examples, those skilled in the art will be able to readily implement many other equivalent forms of the present application.

[0029] The above and other aspects, features and advantages of the present application will become more apparent in view of the following detailed description when taken in conjunction with the accompanying drawings.

[0030] Specific embodiments of the present application are described hereinafter with reference to the accompanying drawings; however, it should be understood that the embodiments applied for are merely examples of the present application, which may be implemented in a variety of ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that obscure the present application. Therefore, the specific structural and functional details applied for herein are not intended to be limiting, but merely serve as a basis and representative basis for the claims to teach those skilled in the art to use the present application in a variety of ways with substantially any suitable detailed structure.

[0031] This specification may use the phrases "in one embodiment," "in another embodiment," "in yet another embodiment," or "in other embodiments," all of which may refer to one or more of the same or different embodiments according to the present application.

[0032] In order to solve the problems in the background technology, the utility model provides a regulating system of a compressor 1, wherein the compressor 1 is arranged on a fuel supply pipeline 6, and the compressor 1 is used to compress the fuel from the fuel tank or the fuel storage device and then deliver it to the equipment or components that use the fuel through the fuel supply pipeline 6, for example, delivering the fuel to the engine of the ship. The compressor 1 can be, but is not limited to, a screw compressor. The main engine of the compressor 1 can connect its inlet to the top of a large tank loaded with LNG (liquefied natural gas) through a pipeline. When the compressor 1 is running, the main engine of the compressor 1 extracts the volatile gas (BOG) of the liquefied natural gas that is partially filled on the top of the large tank and delivers it to a downstream system, such as an engine.

[0033] like Figure 1 As shown, the regulating system of the compressor 1 includes a variable frequency motor 2, a variable frequency regulating component, a pressure detecting component and a controller.

[0034] The variable frequency motor 2 is connected to the compressor 1 to provide driving force for the compressor 1. That is, the variable frequency motor 2 is a driving device of the compressor 1, and the compressor 1 is driven by the variable frequency motor 2 to operate. The flow rate of the compressed gas of the compressor 1 can be adjusted by adjusting the speed of the variable frequency motor 2.

[0035] The frequency conversion adjustment component is connected to the frequency conversion motor 2 and is used to adjust the speed of the frequency conversion motor 2, thereby keeping the pressure at the outlet of the compressor 1 constant. The frequency conversion adjustment component can be a frequency converter 3, and the frequency converter 3 can be connected to the frequency conversion motor 2 in any of the following ways:

[0036] Direct connection: Connect the U, V, W three-phase output of inverter 3 directly to the U, V, W three-phase terminal board of variable frequency motor 2.

[0037] Three-core cable connection: Connect the U, V, W three-phase outputs of the inverter 3 to the U, V, W three-phase lines of the variable frequency motor 2 respectively, and connect the ground wire of the inverter 3 to the ground wire of the variable frequency motor 2. The cable of the variable frequency motor in this method needs to be selected according to the rated current of the variable frequency motor to avoid short circuit or leakage caused by too thin or too thick wire.

[0038] Four-core cable connection: On the basis of the three-core cable connection, a ground wire is added to establish a good grounding between the variable frequency motor 2 and the inverter 3, which can better protect the variable frequency motor 2 and the inverter 3.

[0039] Of course, it is understandable that the frequency conversion adjustment component and the frequency conversion motor 2 can also be connected in other ways, which can be selected according to actual production needs. This is only used as an example and does not constitute a limitation on the scope of protection of the claims.

[0040] The pressure detection component is arranged on the fuel supply pipeline 6, specifically, the pressure detection component is arranged on the fuel supply pipeline 6 at the outlet end of the compressor 1. The pressure detection component is used to detect the pressure at the outlet end of the compressor 1, and generate a pressure signal according to the detected pressure at the outlet end of the compressor 1, and the pressure signal is used to represent the pressure at the outlet end of the compressor 1, and the pressure signal can be transmitted to the controller.

[0041] The controller is connected to the variable frequency regulating component and the pressure detecting component respectively, and the controller is used to receive the pressure signal of the outlet of the compressor 1 detected by the pressure detecting component, and control the variable frequency regulating component to adjust the speed of the variable frequency motor 2 according to the pressure signal. For example, when the pressure signal received by the controller indicates that the pressure at the outlet of the compressor 1 is greater than a certain set pressure value, the controller can control the variable frequency regulating component to reduce the speed of the variable frequency motor 2, and then the variable frequency motor 2 with the reduced speed is used as the driving device of the compressor 1. After the speed of the variable frequency motor 2 is reduced, the compression and pumping capacity of the compressor 1 for the fuel is reduced, and therefore, the pressure at the outlet of the compressor 1 will be reduced to keep the pressure at the outlet of the compressor 1 constant.

[0042] The embodiment of the utility model sets a pressure detection component on the fuel supply pipeline 6 to detect the pressure at the outlet end of the compressor 1, and transmits the pressure signal to the controller. After receiving the pressure signal, the controller controls the frequency conversion adjustment component to adjust the speed of the frequency conversion motor 2, thereby adjusting the compression amount of the fuel by the compressor 1, and realizing stable control of the pressure at the outlet end of the compressor 1.

[0043] In some embodiments, the frequency conversion adjustment component includes a frequency converter 3, which is connected to the frequency conversion motor 2. The frequency converter 3 is used to adjust the speed of the frequency conversion motor 2. The frequency conversion motor 2 and the frequency converter 3 are both connected to the controller.

[0044] When the pressure detection component detects that the pressure at the outlet of the compressor 1 is greater than or equal to the set pressure, the pressure detection component sends a first detection signal to the controller. After receiving the first detection signal, the controller sends a first control signal to the inverter 3. The inverter 3 adjusts the variable frequency motor 2 to reduce its speed according to the first control signal to reduce the pressure at the outlet of the compressor 1, so that the pressure at the outlet of the compressor 1 remains constant.

[0045] In some embodiments, the variable frequency motor 2 is also connected to the controller to send the current signal of the variable frequency motor 2 to the controller. The inverter 3 is also connected to the power supply device of the variable frequency motor 2. When the current signal of the variable frequency motor 2 received by the controller exceeds the set value, it indicates that the variable frequency motor 2 is abnormal, and the controller sends a second control signal to the inverter 3. That is, the controller can compare the magnitude of the current signal of the variable frequency motor 2 with the set value, and determine the abnormality of the variable frequency motor 2 according to the comparison result. After receiving the second control signal, the inverter 3 sends a power-off signal to the power supply device to cut off the power supply of the variable frequency motor 2, thereby protecting the variable frequency motor 2.

[0046] In some embodiments, the regulating system of the compressor 1 further includes a bypass reflux mechanism, which is disposed on the fuel supply line 6 and is used to transport the fuel at the outlet of the compressor 1 back to the inlet of the compressor 1, so as to keep the pressure at the outlet of the compressor 1 constant. For example, when the pressure signal received by the controller indicates that the pressure at the outlet of the compressor 1 is greater than a certain set pressure value, the controller can control the bypass reflux mechanism to be turned on, so that the fuel at the outlet of the compressor 1 can flow back to the inlet of the compressor 1 through the bypass reflux mechanism, and the pressure at the outlet of the compressor 1 will be reduced, so as to keep the pressure at the outlet of the compressor 1 constant.

[0047] In some embodiments, the controller is also connected to the bypass reflux mechanism, and the controller is used to control the opening of the bypass reflux mechanism, thereby keeping the pressure at the outlet of the compressor 1 constant. That is, the controller can adjust the pressure at the outlet of the compressor 1 by controlling the inverter 3 and the bypass reflux mechanism respectively.

[0048] It can be understood that when the opening of the bypass reflux mechanism is 0, it means that the bypass reflux mechanism is closed; when the opening of the bypass reflux mechanism is 100%, it means that the bypass reflux mechanism is fully open; when the opening of the bypass reflux mechanism is between 0 and 100%, the bypass reflux mechanism is opened to the corresponding degree.

[0049] In some embodiments, the controller is further configured to send a third control signal to the bypass reflux mechanism after receiving the first detection signal, so as to increase the opening of the bypass reflux mechanism and keep the pressure at the outlet of the compressor 1 constant.

[0050] The controller is also used to send a fourth control signal to the bypass reflux mechanism after receiving the second detection signal, so as to reduce the opening of the bypass reflux mechanism and keep the pressure at the outlet of the compressor 1 constant.

[0051] That is, the controller can adjust the speed of the variable frequency motor 2 and the opening of the bypass return mechanism in stages to control the pressure at the outlet of the compressor 1 to be constant.

[0052] In some embodiments, the bypass return mechanism includes a bypass return pipeline and a bypass return valve 4, the bypass return valve 4 is arranged on the bypass return pipeline, one end of the bypass return pipeline is connected to the inlet end of the compressor 1, and the other end of the bypass return pipeline is connected to the outlet end of the compressor 1.

[0053] In some embodiments, the pressure detection component includes a pressure transmitter 5, which is connected to the fuel supply pipeline 6 through a connecting pipeline. A first valve and a second valve are arranged in parallel on the connecting pipeline to facilitate online replacement of the pressure transmitter 5 when it fails. Specifically, one port of the first valve is connected to the pressure transmitter 5, and the other port of the first valve is connected to the fuel supply pipeline 6; one port of the second valve is connected to the pressure transmitter 5, and the other port of the second valve is connected to the fuel supply pipeline 6.

[0054] An embodiment of the utility model further provides a ship, comprising a compressor 1, and the ship further comprises a regulating system of the compressor 1 as described in any one of the above embodiments.

[0055] Taking a dual-fuel ship as an example, the dual fuels are diesel and LNG fuel respectively.

[0056] When switching from diesel fuel to LNG fuel:

[0057] When the compressor 1 is running, the controller adjusts the speed of the variable frequency motor 2 and the opening of the bypass return mechanism in stages to control the constant pressure at the outlet of the compressor 1. For example, when the pressure at the outlet of the compressor 1 is higher than the set pressure value, the pressure at the outlet of the compressor 1 is first reduced by reducing the speed of the variable frequency motor 2; if the variable frequency motor 2 has been reduced to the minimum operating speed, and the actual operating pressure at the outlet of the compressor 1 is still higher than the set pressure value, the opening of the bypass return mechanism is increased to continue to reduce the pressure at the outlet of the compressor 1 to the set pressure value.

[0058] After starting up, the inverter 3 adjusts the variable frequency motor 2 to quickly increase the speed to the minimum operating speed of the compressor 1. At this time, the opening of the bypass return mechanism is in the fully open position. All the gas delivered by the compressor 1 returns to the inlet end of the compressor 1 through the bypass return mechanism, and no gas is delivered to the customer's downstream system (such as the ship's engine).

[0059] At this time, the ship is running in diesel fuel mode and the compressor 1 is not required to deliver LNG gas.

[0060] When the ship needs to switch from diesel mode to LNG mode, compressor 1 is required to deliver a large amount of LNG gas in a very short time. At this time, the opening of the bypass return mechanism is adjusted to meet the downstream gas supply demand. For example, at the moment of switching to LNG mode, the controller sends an instruction to the bypass return mechanism of compressor 1 to set it to a certain opening. The specific opening of the bypass return mechanism depends on the consumption of the fuel engine when it is just switched to LNG mode.

[0061] When switching from LNG to diesel fuel:

[0062] When switching between dual fuel modes, compressor 1 can still run smoothly, automatically realizing outlet pressure control and load regulation. When the host mode is switched from LNG mode to diesel mode, the controller sends a state switching signal to compressor 1, notifying compressor 1 of the switch of fuel mode before the pressure at the outlet of compressor 1 fluctuates, so that compressor 1 can respond in advance.

[0063] After receiving the fuel mode state switching signal, the compressor 1 quickly increases the opening of the bypass return mechanism. For example, if the original opening of the bypass return mechanism is 20%, after receiving the state switching signal, the opening of the bypass return mechanism increases by 30% on the basis of the original opening, that is, the opening of the bypass return mechanism is set to 50%. When the fuel mode is switched from LNG to diesel, the LNG consumption is reduced, and the bypass return mechanism is increased to a specific opening before the pressure at the outlet of the compressor 1 is about to increase, so as to avoid the pressure at the outlet of the compressor 1 from increasing, realize the stable control of the pressure at the outlet of the compressor 1, and avoid the compressor 1 from tripping due to the fuel mode switching. At the same time, the pressure fluctuation at the outlet of the compressor 1 will stimulate the controller to adjust the speed of the variable frequency motor 2 and further adjust the opening of the bypass return mechanism, so as to stabilize the pressure at the outlet of the compressor 1. For example, after the bypass return mechanism has increased by 30% and the outlet pressure of the compressor 1 is still high, the controller will send a control signal to reduce the speed of the variable frequency motor 2, so as to reduce the pressure at the outlet of the compressor 1.

[0064] The above describes in detail a number of embodiments of the present invention, but the present invention is not limited to these specific embodiments. Those skilled in the art can make various variations and modifications to the embodiments based on the concept of the present invention, and these variations and modifications should all fall within the scope of protection claimed by the present invention.

Claims

1. A compressor adjustment system, wherein the compressor is arranged on a fuel supply pipeline, characterized in that: The regulating system comprises: A variable frequency motor, connected to the compressor, for providing driving force for the compressor; A frequency conversion adjustment component, which is connected to the frequency conversion motor and is used to adjust the speed of the frequency conversion motor, thereby keeping the pressure at the outlet of the compressor constant; A pressure detection component, which is arranged on the fuel supply pipeline and is used to detect the pressure at the outlet end of the compressor and generate a pressure signal; A controller is connected to the frequency conversion regulating component and the pressure detecting component respectively, and is used to receive the pressure signal of the outlet end of the compressor detected by the pressure detecting component, and control the frequency conversion regulating component to adjust the rotation speed of the frequency conversion motor.

2. The compressor adjustment system according to claim 1, characterized in that: The variable frequency adjustment component includes a frequency converter, which is connected to the variable frequency motor and is used to adjust the speed of the variable frequency motor. The variable frequency motor and the frequency converter are both connected to the controller; When the pressure detection component detects that the pressure at the outlet of the compressor is greater than the set pressure, the pressure detection component sends a first detection signal to the controller; After receiving the first detection signal, the controller sends a first control signal to the frequency converter, and the frequency converter adjusts the variable frequency motor to reduce its speed to reduce the outlet pressure of the compressor and keep the outlet pressure of the compressor constant.

3. The compressor adjustment system according to claim 2, characterized in that: The variable frequency motor is also connected to the controller to send the current signal of the variable frequency motor to the controller; the inverter is also connected to the power supply device of the variable frequency motor, and when the current signal of the variable frequency motor received by the controller exceeds the set value, the controller sends a second control signal to the inverter; After receiving the second control signal, the frequency converter sends a power-off signal to the power supply device to cut off the power supply to the variable frequency motor.

4. The compressor adjustment system according to claim 3, characterized in that: The regulating system of the compressor also includes a bypass return mechanism, which is arranged on the fuel supply pipeline and is used to transport the fuel at the outlet end of the compressor back to the inlet end of the compressor to keep the pressure at the outlet end of the compressor constant.

5. The compressor adjustment system according to claim 4, characterized in that: The controller is also connected to the bypass reflux mechanism, and is used to control the opening of the bypass reflux mechanism, thereby keeping the pressure at the outlet end of the compressor constant.

6. The compressor adjustment system according to claim 5, characterized in that: The controller is further configured to send a third control signal to the bypass reflux mechanism after receiving the first detection signal, so as to increase the opening of the bypass reflux mechanism and keep the pressure at the outlet of the compressor constant; The controller is also used to send a fourth control signal to the bypass reflux mechanism after receiving the second detection signal, so as to reduce the opening of the bypass reflux mechanism and keep the pressure at the outlet end of the compressor constant.

7. The compressor adjustment system according to claim 4, characterized in that: The bypass return mechanism includes a bypass return pipeline and a bypass return valve. The bypass return valve is arranged on the bypass return pipeline. One end of the bypass return pipeline is connected to the inlet end of the compressor, and the other end of the bypass return pipeline is connected to the outlet end of the compressor.

8. The compressor adjustment system according to claim 1, characterized in that: The pressure detection component includes a pressure transmitter, and the pressure transmitter is connected to the fuel supply pipeline through a connecting pipeline. A first valve and a second valve are arranged in parallel on the connecting pipeline.

9. A ship, comprising a compressor, characterized in that: The vessel further comprises a compressor regulation system as claimed in any one of claims 1 to 8.

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