CN216113411U

CN216113411U - Large-flow LNG filling control system with variable PID parameters

Info

Publication number: CN216113411U
Application number: CN202122476550.9U
Authority: CN
Inventors: 徐庆; 邱显军; 王国云; 孙鹏; 陈维银; 罗秀兰
Original assignee: Chongqing Endurance Industry Stock Co Ltd
Current assignee: Chongqing Endurance Industry Stock Co Ltd
Priority date: 2021-10-14
Filing date: 2021-10-14
Publication date: 2022-03-22
Anticipated expiration: 2031-10-14

Abstract

The utility model belongs to the technical field of vehicle LNG filling, and particularly discloses a large-flow LNG filling control system with variable PID parameters, which comprises a PID parameter acquisition device, a PID controller, a frequency converter and an immersed pump, wherein the PID parameter acquisition device is provided with a plurality of information acquisition ends, each information acquisition end is arranged on a liquid adding machine and is used for acquiring the quantity information of the liquid adding machines in a running state, a plurality of PID parameter sets which correspond to the quantity information of the liquid adding machines one by one are arranged in the PID parameter acquisition device, the output end of the PID parameter acquisition device is connected with the PID controller, the output end of the PID controller is connected with the control end of the frequency converter, and the voltage output end of the frequency converter is connected with the immersed pump. By adopting the technical scheme, the PID parameter acquisition device is used for acquiring the corresponding parameter group and inputting the parameter group into the PID controller, so that the PID controller achieves the optimal control effect, and the immersed pump is controlled to operate stably.

Description

Large-flow LNG filling control system with variable PID parameters

Technical Field

The utility model belongs to the technical field of vehicle LNG filling, and relates to a large-flow LNG filling control system with variable PID parameters.

Background

With the development of the LNG (Liquefied Natural Gas) filling industry for vehicles, one LNG immersed pump with two liquid adding machines cannot meet the requirement of a Gas station for quick and efficient filling, and a large-flow LNG filling control mode for the liquid adding machines is adopted by the LNG immersed pump. The ordinary LNG immersed pump control is based on a conventional PID control method, set PID parameters are fixed and unchanged, but in the LNG large-flow filling process, the variable flow of the pump outlet is large due to the fact that multiple liquid adding machines are started and stopped at random, flow mutation is generated, the pressure fluctuation of the pump outlet is large, overpressure shutdown is caused, the safety valve is caused to jump when the pressure fluctuation is serious, and normal gas filling of a gas filling station is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a large-flow LNG filling control system with variable PID parameters, which optimizes the control effect of a PID controller and ensures normal gas filling of a gas station.

In order to achieve the purpose, the basic scheme of the utility model is as follows: a large-flow LNG filling control system with variable PID parameters comprises a PID parameter acquisition device, a PID controller, a frequency converter and an immersed pump;

the PID parameter acquisition device is provided with a plurality of information acquisition ends, each information acquisition end is arranged on one liquid adding machine and is used for acquiring the quantity information of the liquid adding machines in the running state, and a plurality of PID parameter sets which correspond to the quantity of the liquid adding machines in the running state one by one are arranged in the PID parameter acquisition device;

and the PID parameter output end of the PID parameter acquisition device is connected with a PID controller, the output end of the PID controller is connected with the control end of the frequency converter, and the voltage output end of the frequency converter is connected with the immersed pump.

The working principle and the beneficial effects of the basic scheme are as follows: the PID parameter acquisition device is provided with a variable PID parameter group, so that when the flow changes due to the change of the operating states of a certain number of liquid adding machines, the corresponding PID parameter group is output, and the PID controller achieves the optimal control effect. When the immersed pump is unstable due to flow change, the PID controller controls the operation rotating speed of the immersed pump through the frequency converter, and gas filling in the gas filling station process is guaranteed.

Further, the PID parameter acquisition device comprises a memory and a selector switch, wherein the memory is used for storing a plurality of PID parameter sets, the output end of the memory is connected with the PID controller through the selector switch, the information acquisition end is connected with the selector switch, and the parameter sets in the memory are selected through the selector switch.

The storage is used for storing a plurality of PID parameter groups, so that subsequent calling is facilitated, and when the selector switch receives corresponding data, the corresponding parameter groups in the storage are called to be output, so that the structure is simple, and the use is convenient.

Furthermore, the PID parameter acquisition device also comprises a PLC controller, wherein an information acquisition end of the PLC controller is connected with a start-stop switching value output signal end of the liquid adding machine, and an output end of the PLC controller is connected with a change-over switch.

The PLC controller has high reliability and strong performance and is beneficial to use.

The device further comprises a measuring device, wherein the measuring device is arranged at the outlet of the pump of the immersed pump and used for collecting pressure information after the pump, and the output value of the measuring device and the set value of the pressure after the pump are used as two input quantities of the PID controller.

And the PID controller adjusts the rotating speed of the immersed pump according to the actually measured pressure signal and the pressure set value, and ensures that the post-pump pressure of the immersed pump is kept at the set value.

And further, the system also comprises a human-computer interaction device, and the human-computer interaction device is connected with the PID controller.

A user can control the PID controller through the human-computer interaction equipment, and the use is convenient.

And the power supply end of the power supply module is connected with the frequency converter.

The power module is used for supplying power and ensuring normal operation of the equipment.

Further, the measuring device adopts a pressure transmitter.

The pressure transmitter has high acquisition precision and stable performance and is beneficial to use.

Drawings

FIG. 1 is a schematic structural diagram of a variable PID parameter high flow LNG filling control system of the present invention;

fig. 2 is a schematic diagram of a partial structure of a variable PID parameter high flow LNG refueling control system according to the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, unless otherwise specified and limited, it is to be noted that the terms "mounted," "connected," and "connected" are to be interpreted broadly, and may be, for example, a mechanical connection or an electrical connection, a communication between two elements, a direct connection, or an indirect connection via an intermediate medium, and specific meanings of the terms may be understood by those skilled in the art according to specific situations.

As shown in fig. 1 and 2, the utility model discloses a large-flow LNG refueling control system with variable PID parameters, wherein the pressure at the outlet of a pump adopts a PID regulation method, and in the large-flow LNG (Liquefied Natural Gas) refueling control system with one immersed pump having a plurality of liquid feeders, a variable PID parameter set n (n represents a P value, an I value and a D value of n different PID parameters, and n is a positive integer value greater than or equal to 2) is set. The system comprises a PID parameter acquisition device, a PID controller (proportional-integral-derivative controller), a frequency converter and an immersed pump.

The PID parameter acquisition device is provided with a plurality of information acquisition ends, each information acquisition end is arranged on one liquid adding machine to acquire the quantity information of the liquid adding machines in the running state, and a plurality of PID parameter sets (namely 1 liquid adding machine works and corresponds to a first PID parameter, 2 liquid adding machines work and corresponds to a second PID parameter, … …, and n liquid adding machines work and correspond to an nth PID parameter) which are in one-to-one correspondence with the quantity of the liquid adding machines in the running state are arranged in the PID parameter acquisition device. Preferably, the PID parameter acquiring device includes a memory (e.g. 24CXX series, 93CXX series, etc. or a memory provided in the PLC controller) and a switch (e.g. a switch, etc.), the memory is used for storing a plurality of PID parameter sets, and an output end of the memory is electrically connected to the PID controller through the switch. The information acquisition end is electrically connected with the selector switch, and the parameter group in the memory is selected through the selector switch.

More preferably, the PID parameter acquiring device further includes a PLC Controller (Programmable Logic Controller, PLC Controller for short) and a pressure sensor, the pressure sensor is disposed on the liquid adding machine and is configured to acquire a pressure value of the liquid adding machine during operation, and an output end of the pressure sensor is electrically connected to an information acquisition end of the PLC Controller. And the PLC judges whether the liquid adding machine is in an operating state or a non-operating state according to the pressure data. The output and the change over switch electric connection of PLC controller have on the liquid feeding machine to open and stop switching value output signal, and the PLC controller has switching value input point position, and the switching value input of PLC receives liquid feeding machine switching value output signal. In addition, the method for detecting the air conditioning unit in the operating state disclosed in CN113482942A may also be used to detect the number of liquid feeders in the operating state, which may be implemented by detecting whether a control valve of the liquid feeder is closed, and the control valve of the liquid feeder is connected to the measuring device, so as to feed back the opening and closing conditions of the valve to the measuring device.

PID controller and PLC controller integration are integrated integrative and are set up in PLC control module, PID controller and PID parameter acquisition device's PID parameter output electric connection, the output of PID controller and the control end electric connection of converter, the voltage output end of converter and the electric connection of immersed pump, the PID controller passes through the rotational speed of converter control immersed pump, PID control among the prior art for example among the CN 207420899U.

In a preferred scheme of the utility model, the system further comprises a measuring device, the measuring device is installed at the outlet of the immersed pump and used for collecting pressure information after the pump, and an output value of the measuring device and a set value of the pressure after the pump are used as two input quantities of a PID controller or a PLC control module and used for controlling the pressure after the pump of the immersed pump by a subsequent PID controller. The measuring device adopts a pressure transmitter, such as MPM489, HC-3851GP and the like.

In a preferred scheme of the utility model, the system further comprises a human-computer interaction device, the human-computer interaction device is electrically connected with the PID controller, and the human-computer interaction device can adopt a touch screen, a mouse, a keyboard and the like.

In a preferred scheme of the utility model, the system further comprises a power supply module, wherein a power supply end of the power supply module is electrically connected with the frequency converter and used for supplying power, and the power supply module can be a 380V factory power supply or a generator and the like.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the utility model have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the utility model, the scope of which is defined by the claims and their equivalents.

Claims

1. A large-flow LNG filling control system with variable PID parameters is characterized by comprising a PID parameter acquisition device, a PID controller, a frequency converter and an immersed pump;

the PID parameter acquisition device is provided with a plurality of information acquisition ends, each information acquisition end is arranged on one liquid adding machine to acquire the quantity information of the liquid adding machines in the running state, and a plurality of PID parameter sets which correspond to the quantity of the liquid adding machines in the running state one by one are arranged in the PID parameter acquisition device;

2. The system of claim 1, wherein the PID parameter acquiring device comprises a memory and a switch, the memory is used for storing a plurality of PID parameter sets, an output end of the memory is connected to the PID controller through the switch, the information collecting end is connected to the switch, and the parameter sets in the memory are selected through the switch.

3. The PID parameter variable high-flow LNG filling control system according to claim 1, wherein the PID parameter acquisition device further comprises a PLC, an information acquisition end of the PLC is connected with a start-stop switching value output signal end of the liquid filling machine, and an output end of the PLC is connected with a change-over switch.

4. The PID parameter variable mass flow LNG refueling control system as claimed in claim 1 further comprising a measuring device mounted at the pump outlet of the submersible pump for collecting post-pump pressure information, the output value of the measuring device and the post-pump pressure set value being two inputs to the PID controller.

5. The variable PID parameter high flow LNG refueling control system as claimed in claim 1 further comprising a human machine interactive device connected to the PID controller.

6. The variable PID parameter high flow LNG refueling control system as claimed in claim 1 further comprising a power module having a power supply connected to a frequency converter.

7. The variable PID parameter high flow LNG refueling control system as claimed in claim 4 wherein said measuring means employs a pressure transducer.