CN101510092B - Remote control system for water electrolytic hydrogen production - Google Patents

Abstract

The invention belongs to the technical field of hydrogen production by water electrolysis, and relates to a remote control system for hydrogen production by water electrolysis, including field instruments, sensors, actuators, distributed I/O, PLC control stations, local monitoring stations, operating stations, servers and remote Monitoring station and mobile communication terminal, in which field instruments, sensors and actuators are directly connected to distributed I/O, distributed I/O is connected to PLC control station through field bus, and each PLC control station is connected to local monitoring station, The operation station and the server are connected through industrial Ethernet, and the communication between the local monitoring station, the remote monitoring station and the mobile communication terminal is realized through the Internet and the short message service center; for the rectifier cabinet in the hydrogen production device, the Wigner-Ville based Distributed fault diagnosis method. The invention improves the automatic control level of the whole production process of water electrolysis hydrogen production through the network technology, realizes the remote control and online maintenance of the system, greatly improves the production efficiency, and reduces the maintenance cost.

Description

Water electrolysis hydrogen production remote control system

technical field

The invention belongs to the technical field of water electrolysis hydrogen production, and in particular relates to a control system of water electrolysis hydrogen production equipment.

Background technique

Hydrogen is a clean energy with high calorific value. At present, the main hydrogen production processes include: water electrolysis hydrogen production, thermochemical cycle decomposition water hydrogen production, photochemical hydrogen production, fossil fuel hydrogen production and biological hydrogen production. Among them, water electrolysis hydrogen production converts power grid electricity into hydrogen energy, which has the characteristics of high hydrogen purity, simple process and equipment, non-polluting production process, mature related process technology, high energy conversion efficiency, and flexible hydrogen production scale. The control equipment of the traditional water electrolysis hydrogen production device is usually realized by industrial computer and PLC controller. The multi-channel analog signals collected by the instruments and meters in the explosion-proof area are directly connected with the PLC controller in the non-explosion-proof area. The installation of the control system is complex, safe and anti-interference. performance and reliability. It is a trend in this field to use network control technology to control hydrogen production equipment to realize the functions of unattended system, full automation, centralized management and remote fault diagnosis. However, due to the speed, distance and security of network transmission And other impacts, related technologies and their applications are not yet very mature.

Contents of the invention

For the existing water electrolysis hydrogen production system, the compatibility is not high, the data transmission rate is low, the signal interconnection lines are many, the interference problem is serious, the system structure is complicated, the data information cannot be shared, the fault processing cycle is long, and the integration of intelligence and automation To solve such problems, the present invention provides an implementation scheme of a remote monitoring system for hydrogen production by water electrolysis:

A remote control system for hydrogen production by water electrolysis, including field instruments, sensors, actuators, distributed I/O, PLC control station, local monitoring station, operation station, server, remote monitoring station and mobile communication terminal, wherein the field instrument , Sensors and actuators are directly connected to the distributed I/O, and the distributed I/O is connected to the PLC control station through a field bus. Each PLC control station controls a water electrolysis hydrogen production equipment, and each PLC control station is connected to the local The monitoring station, operation station, and server are connected through industrial Ethernet, and the communication between the local monitoring station, the remote monitoring station and the mobile communication terminal is realized through the Internet and the short message service center respectively; for the rectifier cabinet in the hydrogen production device, signal extraction The location is the DC signal output by the rectifier cabinet. The signal is directly sent to the distributed I/O, then forwarded to the PLC control station through the field bus, and finally sent to the local monitoring station. The following signal analysis is realized on the local monitoring station: According to the signal In the frequency band where the fault signal is located, select the number of wavelet decomposition layers n; select db1 and db3 as wavelet mother functions, and perform n-1 layer multi-resolution decomposition respectively, and decompose the original fault signal into n sequences, each sequence has only one Components: Wigner-Ville distribution analysis is performed on each component, and then the Wigner-Ville distribution of each sequence is combined to form the time-frequency distribution of the original signal to realize multi-scale analysis of the signal.

As a preferred implementation, the local monitoring station is provided with two mutually independent and mutually hot-standby local host computers to realize redundant control.

The invention is a combination of industrial Ethernet and field bus, strong real-time performance, information sharing, remote monitoring function, intelligent adjustment of process parameters, and the realization of the whole process of hydrogen production (pre-start inspection, start-up operation, operation and parking) The fully automated water electrolysis hydrogen production remote control system can be used to build a new hydrogen production equipment control system, and can also transform the existing hydrogen production equipment control system on the basis of ensuring the maximum non-repetitive investment in construction. The present invention has following technical effect:

(1) The automation control level of the entire production process of hydrogen production by water electrolysis is improved through network technology, and the remote control and online maintenance of the system are realized, which greatly improves production efficiency and reduces maintenance costs.

(2) It has good scalability and can add new hydrogen production equipment control systems to the network at any time without changing the current network structure and functions.

(3) Due to the combination of industrial Ethernet and bus, a large number of cables are saved, which not only reduces the cost, but also improves the compatibility and transmission rate of the hydrogen production control system.

(4) The present invention performs distributed I/O control on units such as field instruments, sensors, and actuators, and changes the connection between the explosion-proof area and the non-explosion-proof area of the hydrogen production site into a bus connection with intrinsically safe characteristics, The reliability and security of the system are high.

(5) Adopt advanced PID control method to control the key parameters of the hydrogen production process, improve the control accuracy and product production quality, increase the safety and reliability of equipment operation, reduce the failure rate of equipment, and reduce equipment maintenance costs .

(6) The Wigner-Ville signal analysis strategy based on wavelet transform is used to diagnose rectifier faults online. Hydrogen equipment downtime and maintenance costs, improve system reliability.

(7) The short message alarm system based on classified faults greatly improves the mobility and reliability of the remote control of the hydrogen production control system based on the network control, and complements the wired network.

Description of drawings

Fig. 1 is a block diagram of the system control structure of the present invention.

Figure 2 is a block diagram of Wigner-Ville time-frequency analysis strategy based on wavelet transform.

Fig. 3 is a schematic diagram of rectifier cabinet fault detection based on DSP.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and embodiments.

The remote control system of the water electrolysis hydrogen production device of the present invention is mainly composed of field instruments, actuators, PLC control stations, local monitoring stations, and remote monitoring stations, and its basic structure is shown in Figure 1.

The invention mainly adopts the industrial Ethernet technology and the PROFIBUS bus technology of Siemens to realize the network control of multiple hydrogen production equipment. The system is mainly composed of field instruments, sensors, solenoid valves, relays and other actuators, PLC control station, local monitoring station, remote monitoring station and server.

As shown in Figure 1, the entire network can be divided into three layers. The lowest layer connects the distributed I/O——ET200 with the unit-level PLC control station through the PROFIBUS-DP bus. The middle layer uses industrial Ethernet technology to realize the monitoring station, operation The communication between various intelligent automation units such as station, server and PLC control station, and the uppermost layer realizes functions such as remote monitoring and remote after-sales service of hydrogen production equipment through the Internet and Short Message Service Center (SMSC).

The smart instruments, sensors, solenoid valves, relays and other actuators at the lowest layer of the network generally do not have PROFIBUS bus interface devices, so the present invention directly connects them with distributed I/O, which can save costs and reduce system development time . For explosion-proof areas and non-explosion-proof areas, distributed I/Os with different safety levels are used, ET200isp is used for explosion-proof areas, and standard ET200M is used for non-explosion-proof areas. The transmission rate between each distributed I/O and between the PLC control station Up to 1.5Mbps.

Each PLC control station is a master station, and there are multiple distributed I/O slave stations communicating with it through the PROFIBUS DP bus, and they are jointly responsible for controlling a corresponding water electrolysis hydrogen production equipment, realizing the modularization and integration of the system. Decentralized control.

In Figure 1, n PLC control stations are responsible for the control of n water electrolysis hydrogen production equipment, which are independent of each other, but they are all connected to the industrial Ethernet through CP343-1 to realize data communication with the upper monitoring station, operation station and server and command transmission, and at the same time, the local hydrogen production equipment can be controlled by the touch screen man-machine interface of the control station itself. The control system uses two local host computers to form a monitoring station to monitor all parameters of each set of hydrogen production equipment, and connects to industrial Ethernet through CP1612. The two upper computers use the same application program, and any upper computer can monitor and control any parameter of any hydrogen production equipment, and the two are hot standby for each other. The monitoring function mainly includes operation control, alarm, parameter setting and modification, and report generation and printing. By clicking "Start", the device can automatically complete nitrogen replacement, lye circulation, parameter setting, adjust electrolysis current, electrolysis voltage, turn on the analysis instrument for data detection, and automatically complete the entire process of tank filling and hydrogen storage. The monitoring station uses screens instead of secondary instruments and hand-operated devices. Under manual conditions, the opening of the regulating valve can be controlled through the screen to realize the adjustment process of tank pressure, alkali temperature and hydrogen-oxygen liquid level, and can be switched to automatic state as required. In order to facilitate the stability of the system or the debugging of related control software. For the key parameters in water electrolysis hydrogen production, such as tank temperature, tank pressure and separator liquid level, the present invention adopts Anti-windup PID controller to control so as to reduce limiter link and improve control accuracy. The system can memorize and store various functional states and fault phenomena, and can perform simple self-diagnosis. By setting alarms for important parameters and viewing alarms, production accidents can be avoided and accident analysis can be facilitated.

The server is responsible for storing all the data required for remote monitoring of each hydrogen production equipment obtained by each monitoring station, and has a good man-machine interface screen for remote engineers and managers to access. AES encryption technology is used for data transmission and access, with the key The management can ensure the security of data transmission and prevent external factors from monitoring data transmission through the network to steal related software programs. Relevant users with authorization can use their own keys to perform corresponding remote operations according to their user levels. When the hydrogen production system fails, the system can send classified alarm information to relevant personnel in time through the Internet and mobile phone text messages to ensure timely and correct response to the alarm information. parameters, rewrite the PLC program through the Internet, and quickly troubleshoot. When the user's needs change or the software of the remote control device has a corresponding upgrade version, the manufacturer can also realize the online update of the control software at the remote end of the Internet.

For the important equipment rectifier cabinet in the hydrogen production device, the present invention proposes a Wigner-Ville signal analysis strategy based on wavelet transform as shown in FIG. 2 . According to the actual diagnosis effect, this strategy first selects db1 and db3 as wavelet mother functions, and performs n-1 layer multi-resolution decomposition respectively, decomposes the original fault signal s into multiple sequences, and each sequence has only one component (s1, s2, s3, ... sn). The number n of wavelet decomposition layers depends on the frequency band of the fault signal in the signal, and 5-7 is generally selected here. The specific number is determined by the type of fault and the actual fault detection effect. Then analyze the Wigner-Ville distribution of each component, and then combine the Wigner-Ville distributions of each sequence to form the time-frequency distribution WVDs of the original signal, which can eliminate interference items without affecting the time-frequency aggregation of the Wigner-Ville distribution and realize multi-scale analysis of signals.

For the more detailed content of the Wigner-Ville distribution analysis method, please refer to the following paper: Wavelet Transform for the Suppression of Wigner-Ville Distribution Intersection Items/Fu Haiwei, Fu Junmei//Journal of Xi'an Petroleum Institute: Natural Science Edition-2001.16(5). -37-39. This article presents a Wigner-Ville distribution cross-item suppression method based on wavelet transform, but this method first analyzes the original signal for Wigner-Ville distribution time-frequency analysis, and then decomposes and reconstructs the time-frequency distribution by wavelet to obtain New Wigner-Ville distribution map. However, the present invention first performs multi-scale decomposition on the original signal, then performs Wigner-Ville distribution analysis on the decomposed multiple groups of signals to obtain respective Wigner-Ville time-frequency distributions, and finally combines them to obtain the Wigner-Ville distribution of the original signals .

In the process of rectifier cabinet fault diagnosis using the above strategy, the signal extraction location is the DC signal output by the rectifier cabinet, and the signal is directly sent to the distributed I/O, as shown in Figure 3. Then it is forwarded to the PLC control station through the field bus, and finally transmitted to the local monitoring station, where the signal analysis strategy shown in Figure 2 is realized on the local monitoring station. The fault diagnosis and analysis strategy realizes the online analysis and diagnosis of various common faults of the rectifier cabinet, and reduces the downtime and maintenance costs of hydrogen production equipment.

Claims (2)

1. A remote control system for hydrogen production by water electrolysis, including field instruments, sensors, actuators, distributed I/O, PLC control station, local monitoring station, operation station, server, remote monitoring station and mobile communication terminal, wherein, Field instruments, sensors, and actuators are directly connected to the distributed I/O, and the distributed I/O is connected to the PLC control station through a field bus. Each PLC control station controls a water electrolysis hydrogen production equipment, and each PLC control station It is connected with the local monitoring station, operation station and server through industrial Ethernet, and the communication between the local monitoring station, the remote monitoring station and the mobile communication terminal is realized through the Internet and the short message service center respectively; for the rectifier cabinet in the hydrogen production device, The signal extraction position is the DC signal output by the rectifier cabinet. The DC signal is directly sent to the distributed I/O, then forwarded to the PLC control station through the field bus, and finally transmitted to the local monitoring station. The following DC signal is realized on the local monitoring station Analysis: (1) According to the frequency band of the fault signal in the direct current signal, select the number of wavelet decomposition layers n; (2) select db1 and db3 as wavelet mother functions, and perform n-1 layer multi-resolution decomposition respectively, and divide the direct current signal The fault signal is decomposed into m sequences, and each sequence has only one component; (3) Wigner-Ville distribution analysis is performed on each component, and then the Wigner-Ville distribution of each sequence is combined to form the fault signal in the DC signal. Frequency distribution, to achieve multi-scale online analysis of DC signals. 2. The remote control system for hydrogen production by water electrolysis according to claim 1, characterized in that two local host computers that are independent of each other and are in hot standby for each other are set at the local monitoring station to realize redundant control.

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