Hydraulic oil system for hydraulic drive hydrogen compressor of hydrogen refueling station

Abstract

The utility model discloses a hydraulic oil system for a hydraulic drive hydrogen compressor of a hydrogen refueling station. The problem that the oil pumping amount of an existing hydraulic oil pump is not matched with operation of a hydrogen compressor when the outlet pressure of the hydrogen liquid-driven compressor changes is mainly solved. The system comprises an oil tank used for containing hydraulic oil, a hydraulic drive pump used for compressing hydrogen, a hydraulic oil pump connected between the oil tank and the hydraulic drive pump through a corresponding pipeline, and a flow regulating valve and a flow meter which are sequentially connected in a downstream pipeline of the hydraulic oil pump, one end of the overflow valve is arranged in a pipeline between the hydraulic oil pump and the flow regulating valve in a connected mode, and the other end of the overflow valve is communicated to the oil tank. And the pressure transmitter is in communication connection with the controller and is used for detecting the exhaust pressure of the hydrogen compressor. According to the system, the problems of cylinder collision, vibration, noise and the like in the operation process of the hydraulic drive compressor can be effectively avoided, and the operation safety is high.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogenation equipment, and in particular to a hydraulic oil system for a liquid-driven hydrogen compressor in a hydrogenation station. Background Art

[0002] With the continuous development of the hydrogen energy industry, liquid-driven hydrogen compressors, as a key piece of equipment, are widely used in hydrogen transportation, storage, and refueling at hydrogen refueling stations. Specifically, a liquid-driven hydrogen compressor compresses hydrogen using hydraulic oil as a medium. Its operating principle primarily utilizes a hydraulic pump to convert hydraulic oil pressure into mechanical energy, driving the reciprocating motion of the piston inside the compressor. During this process, low-pressure hydrogen is drawn into the compressor. After being compressed by the piston, high-pressure hydrogen is discharged from the system, thus achieving hydrogen compression.

[0003] The main components of a liquid-driven hydrogen compressor include a driver, a compressor body, and a control system. The driver, typically a hydraulic oil pump, provides the liquid pressure required for compression. The compressor body, comprised of key components such as the piston and cylinder, compresses the hydrogen. The control system monitors and adjusts the compressor's operating status to ensure efficient and stable operation.

[0004] Existing hydraulic oil systems for liquid-driven hydrogen compressors generally use a combination of a hydraulic oil pump and an oil distribution valve to drive the reciprocating motion of the liquid-driven hydrogen compressor, thereby achieving the effect of pressurizing the hydrogen. However, when the hydraulic oil pump and the oil distribution valve are in coordination and the compressor outlet pressure is low, the hydraulic oil pump's oil output is still relatively high, causing problems such as cylinder collision, vibration, and loud noise during operation of the liquid-driven hydrogen compressor. This can also easily lead to loosening and damage of the liquid-driven compressor cylinder, causing loosening of the hydraulic oil pipeline or hydrogen pipeline connection, posing the risk of hydraulic oil and hydrogen leakage. In addition, the oil pressure in the hydraulic oil pump outlet pipeline can reach up to 35MPa, and the hydrogen pressure can reach up to 45MPa. Hydrogen is also flammable and explosive. Once a leak occurs, it will cause significant damage to equipment and personnel.

[0005] The information disclosed in this background technology section is only used to deepen the understanding of the background technology of the present disclosure and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0006] In view of at least one of the above technical problems, the present disclosure provides a hydraulic oil system for a liquid-driven hydrogen compressor in a hydrogen refueling station, which mainly solves the problem that the pumping oil volume of the existing hydraulic oil pump does not match the operation of the hydrogen compressor when the outlet pressure of the hydrogen liquid-driven compressor fluctuates.

[0007] According to one aspect of the present disclosure, a hydraulic oil system for a liquid-driven hydrogen compressor in a hydrogen filling station is provided, which includes an oil tank for containing hydraulic oil, a liquid-driven pump for compressing hydrogen, a hydraulic oil pump connected between the oil tank and the liquid-driven pump through corresponding pipelines, a flow regulating valve and a flow meter sequentially connected in a pipeline downstream of the hydraulic oil pump, a controller for obtaining flow information output by the flow meter and correspondingly regulating the flow of the flow regulating valve, an overflow valve having one end connected in a pipeline between the hydraulic oil pump and the flow regulating valve and the other end connected to the oil tank, and a pressure transmitter communicatively connected to the controller for detecting the exhaust pressure of the hydrogen compressor.

[0008] In some embodiments of the present disclosure, an oil suction filter is provided in the pipeline between the oil tank and the liquid drive pump.

[0009] In some embodiments of the present disclosure, the liquid-driven pump includes a drive motor.

[0010] In some embodiments of the present disclosure, the controller is a PLC controller, and the flow control valve adjusts its opening in response to an analog signal output by the PLC controller.

[0011] In some embodiments of the present disclosure, an oil distribution valve group is provided in the pipeline between the flow meter and the liquid drive pump; the oil return port of the oil distribution valve group is connected to the oil tank through an oil return pipeline.

[0012] In some embodiments of the present disclosure, an oil return filter is correspondingly connected to the oil return port of the oil tank.

[0013] One or more technical solutions provided in the embodiments of this application have at least any of the following technical effects or advantages:

[0014] 1. The PLC controller adjusts the flow control valve opening according to the compressor outlet pressure, thereby adjusting the hydraulic oil volume in the oil pipeline, ensuring that the hydraulic oil pumping volume is compatible with the operating requirements of the hydraulic drive pump, avoiding problems such as cylinder collision, vibration and noise during compressor operation, and ensuring system operation safety.

[0015] 2. Installing a flow meter downstream of the flow control valve enables real-time measurement of the flow in the oil pipeline, which is then fed back to the PLC controller to determine the difference between the measured flow rate and the expected flow rate. This forms a closed-loop negative feedback control structure to ensure the accuracy of the flow control valve in controlling the hydraulic oil flow.

[0016] 3. The overflow valve allows excess hydraulic oil between the hydraulic oil pump and the flow control valve to flow back to the oil tank, thereby effectively avoiding the problem of pressure increase in the oil pipeline between the hydraulic oil pump and the flow control valve due to excess hydraulic oil, which affects the operation and safety of the system and equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a principle block diagram of the hydraulic oil system in one embodiment of the present application. DETAILED DESCRIPTION

[0018] The procedures involved or relied upon in the following embodiments are all conventional or simple procedures in the art, and those skilled in the art can make conventional selections or adaptive adjustments based on specific application scenarios. The devices involved in the following embodiments, unless otherwise specified, are all conventional commercially available products.

[0019] In order to better understand the technical solution of the present application, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0020] In order to solve the problem that the oil output of the hydraulic oil pump of the liquid-driven hydrogen compressor in the existing hydrogen refueling station cannot be adjusted according to the compressor outlet pressure, thereby causing problems such as cylinder collision, vibration and noise in the liquid-driven hydrogen compressor during operation and the risk of hydraulic oil and hydrogen leakage, this example discloses a hydraulic oil system for the liquid-driven hydrogen compressor in the hydrogen refueling station.

[0021] See also Figure 1 The hydraulic oil system for the liquid-driven hydrogen compressor at the hydrogen filling station includes an oil tank, which is used to contain the hydraulic oil required for the operation of the liquid-driven pump. The hydraulic oil pump inputs high-pressure hydraulic oil into the compressor cylinder as the power source for compressing hydrogen in the compressor cylinder, and realizes the output of compressed hydrogen through the reciprocating action of the piston compressor. In order to ensure that the liquid-driven pump can reliably obtain hydraulic oil from the oil tank, in this embodiment, the liquid-driven pump is connected to the oil tank through an oil pipeline, and a hydraulic oil pump is connected in series in the oil pipeline, and the hydraulic oil stored in the oil tank is extracted by the hydraulic oil pump. Specifically, in this embodiment, the hydraulic oil pump includes a drive motor, which serves as the power source of the hydraulic oil pump and realizes the hydraulic oil absorption action after power is turned on. In addition, in some other embodiments, considering that the hydraulic oil may be mixed with debris from wear of mechanical components and other debris after multiple cycles of use, which may affect the operation of the system and the safety of equipment operation, in this example, an oil suction filter is connected in series in the oil pipeline between the oil tank and the hydraulic oil pump, and the hydraulic oil entering the hydraulic oil pump is filtered by the oil suction filter to ensure that there are no impurities in the hydraulic oil.

[0022] Considering that piston-type liquid-driven compressors are generally used with constant-power variable-displacement hydraulic oil pumps, if the compressor outlet pressure decreases, the liquid-driven compressor will be overpowered, which will cause problems such as cylinder collision, vibration, and high noise during compressor operation, seriously interfering with the normal and safe operation of the compressor. For this reason, in this embodiment, see Figure 1A flow regulating valve is connected in series in the oil pipeline downstream of the hydraulic oil pump between the oil tank and the liquid drive pump. The flow regulating valve is used to adjust the amount of hydraulic oil entering the liquid drive pump, thereby avoiding excessive amount of hydraulic oil entering the liquid drive pump, which causes the hydraulic oil amount to not match the compressor operation requirements and poses a safety hazard.

[0023] In addition, although the flow control valve can adjust the amount of hydraulic oil flowing through the flow control valve by adjusting the valve body opening, when the compressor outlet pressure decreases, that is, the compression demand decreases, the flow control valve needs to be used to reduce the amount of hydraulic oil delivered to the hydraulic drive pump. Since the hydraulic oil pumped to the flow control valve by the hydraulic oil pump cannot completely pass through the flow control valve, the pressure in the oil pipeline between the hydraulic oil pump and the flow control valve increases, affecting the structural safety of the hydraulic drive pump and the flow control valve and the pipeline safety, posing a safety hazard. For this reason, see Figure 1 In this embodiment, an overflow valve is provided. Specifically, one end of the overflow valve is connected to the oil delivery pipeline between the hydraulic oil pump and the flow regulating valve through a pipeline, and the other end of the overflow valve is connected to the oil tank. Thus, the return flow of excess hydraulic oil to the oil tank is achieved through the return pipeline where the overflow valve is located, thereby avoiding the accumulation and increase of the hydraulic oil pressure between the hydraulic oil pump and the flow regulating valve as the hydraulic oil pump works. The excess hydraulic oil that cannot pass through the flow regulating valve can be returned through the overflow valve in time.

[0024] In order to realize reliable adjustment of the opening of the flow control valve according to the compression working condition, in this embodiment, see Figure 1 The hydraulic oil system also includes a controller. In this embodiment, the controller is specifically a PLC controller, and the flow control valve is connected to the PLC controller via analog communication. Considering that the opening of the flow control valve, that is, the amount of hydraulic oil required by the liquid drive pump, is related to the compressor outlet pressure, in this embodiment, the hydraulic oil system also includes a pressure transmitter for detecting the exhaust pressure of the hydrogen compressor. The pressure transmitter is connected to the PLC controller via analog communication. The PLC controller detects and obtains the compressor outlet pressure value through the pressure transmitter, and thus outputs a corresponding control signal to adjust the opening of the flow control valve according to changes in the outlet pressure. The flow control valve controls the hydraulic oil volume of the flow valve body by responding to the analog signal output by the analog output module of the PLC controller.

[0025] To ensure the reliability of the flow control valve's operation and ensure that the flow control valve opening matches the desired hydraulic oil flow through it, in this embodiment, a flow meter is connected in series to the oil pipeline downstream of the corresponding flow control valve to monitor the flow of hydraulic oil in the oil pipeline after it is regulated by the flow control valve. The flow meter and the PLC controller utilize analog communication. The analog input module connected to the PLC controller outputs an analog signal for flow rate feedback. The PLC controller then calculates the difference between the flow rate information fed back by the flow meter and the desired flow rate. This difference is used as a control signal to further adjust the flow control valve, forming a closed-loop feedback control loop, thereby enhancing the control accuracy and reliability of the flow control valve.

[0026] In addition, see Figure 1 In this embodiment, an oil distribution valve group is also connected in series in the oil delivery pipeline between the flow meter and the hydraulic drive pump, and bidirectional oil flow is achieved between the oil distribution valve group and the hydraulic drive pump to realize the distribution and supply of hydraulic oil to the hydraulic drive pump. In addition, the oil distribution valve group also includes a return oil port for discharging hydraulic oil to the oil tank. In this example, the return oil port is connected to the oil tank through a return oil pipe. Considering that the hydraulic oil may carry impurities such as metal debris generated by mechanical wear after circulating in the system, in order to avoid the return hydraulic oil from contaminating the hydraulic oil in the tank, in some other embodiments, a return oil filter is connected to the return oil line. In some other embodiments, the return line downstream of the overflow valve is connected to the return oil filter upstream of the return oil filter of the return oil line, so that the return oil line and the return line share a return oil filter to filter the hydraulic oil returning to the oil tank, thereby avoiding affecting the normal and safe operation of the hydraulic oil system.

[0027] Although some preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0028] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of the inventive concept. Thus, if such changes and modifications fall within the scope of the claims of this application and their equivalents, this application is intended to include such changes and modifications.

Claims

1. A hydraulic oil system for a liquid-driven hydrogen compressor in a hydrogenation station, characterized in that: It includes an oil tank for containing hydraulic oil, a liquid drive pump for compressing hydrogen, a hydraulic oil pump connected between the oil tank and the liquid drive pump through a corresponding pipeline, a flow regulating valve and a flow meter sequentially connected to the downstream pipeline of the hydraulic oil pump, a controller for obtaining the flow information output by the flow meter and correspondingly regulating the flow of the flow regulating valve, an overflow valve with one end connected to the pipeline between the hydraulic oil pump and the flow regulating valve and the other end connected to the oil tank, and a pressure transmitter communicated with the controller for detecting the exhaust pressure of the hydrogen compressor.

2. The hydraulic oil system according to claim 1, characterized in that: An oil suction filter is provided in the pipeline between the oil tank and the liquid drive pump.

3. The hydraulic oil system according to claim 1, characterized in that: The liquid-driven pump includes a drive motor.

4. The hydraulic oil system according to claim 1, characterized in that: The controller is a PLC controller, and the flow control valve responds to the analog signal output by the PLC controller to adjust the opening.

5. The hydraulic oil system according to claim 1, characterized in that: An oil distribution valve group is provided in the pipeline between the flow meter and the liquid drive pump; the oil return port of the oil distribution valve group is connected to the oil tank through an oil return pipeline.

6. The hydraulic oil system according to claim 5, characterized in that: An oil return filter is correspondingly connected to the oil return port of the oil tank.

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