Disclosure of Invention
The invention aims to: aiming at the existing problems, the invention provides a dual-redundancy safety monitoring control method for an LNG filling ship, which comprises two mutually independent processors, solves the problem that the data acquisition device or the processor fails to cause the incorrect detection data or the data loss, and further improves the efficiency of finding out the failure points of the data acquisition device and the processor.
The technical scheme adopted by the invention is as follows:
the double-redundancy safety monitoring control method of the LNG filling ship comprises a double-redundancy safety monitoring control system of the LNG filling ship, and is characterized in that the system comprises a power supply, two identical data acquisition devices, a safety processor, a control processor and a communication module, wherein the communication module is used for communicating and transmitting data of the safety processor and the control processor, and the data acquisition devices are respectively a safety data acquisition device in signal connection with the safety processor and a control data acquisition device in signal connection with the control processor.
By adopting the structure, the safety data acquisition device and the control data acquisition device respectively store the collected data into the safety processor and the control processor, so that double data storage is realized, and the problems of data loss or discontinuity of one processing system can be prevented. Still be provided with the communication module who carries out data interchange between safety processor and control processor, can carry out communication and transmission to the data that two treater received, ensure the accuracy of data, when data acquisition device trouble, can in time discover the fault location.
Furthermore, the safety processor and the control processor respectively comprise a CPU module, a digital quantity input module, a digital quantity output module and an analog quantity input module.
Furthermore, the data collected by the data collecting device comprises one or a combination of a plurality of storage tank pressure, storage tank liquid level, liquid feeding collecting pipe pressure, supercharger outlet temperature, NG heater outlet temperature, instrument wind pressure and combustible gas.
In the process of filling, supplying and transporting LNG fuel by the LNG filling wharf boat, a plurality of indexes such as pressure intensity, liquid level height, temperature and the like in a tank or in a pipe of storage and transportation equipment reflect the safety of the LNG filling wharf boat, and the data are monitored in real time.
Further, the system also comprises low-voltage electrical equipment, an alarm system and an emergency device;
the low-voltage electrical equipment comprises one or a combination of a plurality of surge protectors, safety gates, switching on light input isolators, circuit breakers and open-phase protectors;
the alarm system comprises one or a combination of a plurality of audible and visual alarms, a fire alarm and a gas alarm;
the emergency device comprises an emergency shut-off valve and/or an ESD system.
Furthermore, the system also comprises an industrial control computer and/or a touch screen.
By adopting the structure, the setting of system parameters, the control of the system and the real-time monitoring of data are convenient.
Further, the safety data acquisition device and the control data acquisition device are arranged at the same position.
The pressure, temperature and other conditions at different positions are different, the data may be different, and due to the adoption of the structure, the data accuracy is higher, and the problem of false alarm is prevented.
Furthermore, the power supply is a dual-redundancy power supply and comprises an external power supply and a storage power supply which are connected in parallel.
Due to the adoption of the structure, when the external power supply is abnormal (power loss), the storage battery supplies power to the system, so that the system can still normally work for a period of time under the condition that the external power supply loses power.
A dual-redundancy safety monitoring control method of an LNG filling ship is characterized by comprising the following steps:
firstly, respectively accessing data acquired by two data acquisition devices into a secure processor analog input module and a control processor analog input module;
secondly, converting the acquired data into decimal data by the security processor and the control processor, respectively storing the decimal data in the intermediate register A and the intermediate register B, and respectively storing the highest threshold values of the security processor and the control processor in the register G and the memory H;
comparing the data collected by the safety processor and the control processor with the highest threshold values in the register G and the memory H respectively;
and step four, comparing the data in the register B with the data in the register H, controlling the processor alarm system to alarm, and when the data in the register A is larger than the data in the register G, the safety processor alarm system alarms and emergently cuts off the valve action.
Further, the method also comprises the following steps: when the data in the secure processor and the control processor is less than the highest threshold,
fifthly, the control processor reads the data in the register A and stores the data in a continuous intermediate register C;
sixthly, the control processor calculates the difference value of the data in the register B and the register C through subtraction, and stores the calculated difference value in the intermediate register D; setting the lower limit value and the upper limit value of the allowable error value of the data acquired by the two data acquisition devices in a register E and a register F respectively;
and seventhly, comparing the difference value in the register D with the register E and the register F respectively.
Further, in the sixth step, when the data in the register D is greater than the data in the register F, or the data in the register D is less than the data in the register E, the alarm system gives an alarm.
Further, the safety controller and/or the control processor initiates an emergency action, wherein the emergency action comprises emergency cut-off on/off; the ESD system acts.
From the above, compare the signal that two treater received through the intranet, when the system monitored data unusual, the emergency action was started through the procedure that sets up to the system, can carry out the preliminary treatment before artifical intervention, reduces danger to minimumly.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
1. according to the invention, the two data acquisition devices respectively store the collected data into the two processors, so that double data storage is realized, and the problems of data loss or discontinuity caused by a problem of one processing system can be prevented.
2. According to the invention, the data stored in the two processors are transmitted through the communication module, the accuracy of the data is ensured, and the data in the two processors are compared through the control processor, so that when a data acquisition device fails, the failure position can be found in time.
3. The invention is provided with an alarm system and corresponding emergency actions, when the system monitors that the data is incorrect, the system starts the alarm and the corresponding emergency actions, and the danger can be reduced to the minimum before manual intervention.
Detailed Description
All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.
Any feature disclosed in this specification (including any accompanying claims, abstract) may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.
Example 1
As shown in fig. 1-2, a dual-redundancy safety monitoring control system for an LNG refueling ship is provided, which includes a power supply, two identical data acquisition devices, a safety processor, a control processor, a communication module, an industrial control computer (in other embodiments, a touch screen may also be used), a low-voltage electrical device, an emergency device, and an alarm system.
The communication module compares data of the safety processor and the control processor, the data acquisition devices are respectively a safety data acquisition device connected with the safety processor through signals and a control data acquisition device connected with the control processor through signals, and the safety processor and the control processor are both connected with an alarm system; according to actual conditions, parameters of the system are set through the industrial control computer or the touch screen, and when data danger or data are monitored to be incorrect, an alarm or prompt is given out on the industrial control computer or the touch screen.
The safety processor and the control processor comprise a CPU module, a digital quantity input module, a digital quantity output module and an analog quantity input module; the power supply is a dual-redundancy power supply and comprises an external power supply and a storage power supply which are connected in parallel;
wherein, data acquisition device includes: (1) the device comprises a pressure/temperature sensor, a liquid level monitoring device, a pressure/temperature sensor, a temperature sensor and a controller, wherein the pressure/temperature sensor is arranged in an LNG filling pipe, a supply pipe, a liquid phase pipe, a gas phase pipe and other LNG pipelines, the liquid level monitoring device is used for monitoring the liquid level height of the storage tank, the pressure/temperature sensor is arranged in the LNG filling pipe, the supply pipe, the liquid phase pipe, the gas phase pipe and other LNG pipelines, the temperature sensor is used for monitoring the temperature at the outlet of a booster and the outlet of an NG heater, and the sensors for monitoring the;
the emergency cut-off valve is communicated with a pneumatic valve compressed air pipe through a filter by adopting an instrument air system and is used for driving the pneumatic valve to be opened and closed;
wherein the low-voltage electrical equipment comprises a surge protector, a safety grid, an on-light input isolator, a circuit breaker and a phase loss protector,
the surge protector is used for preventing lightning waves from rushing into the signal line to damage equipment;
a safety barrier for limiting the voltage or current supplied to the intrinsically safe circuit to within a certain safety range;
the switching value input isolator is used for physically isolating the digital value input signal in the explosion danger area from the PLC;
the circuit breaker is used for automatically breaking and protecting equipment when the current in the circuit exceeds the rated current;
the open-phase protector is used for detecting the phase sequence and the open phase of the three-phase power supply and providing a fault signal of the three-phase power supply system for the PLC; if the three-phase power supply is abnormal, the open-phase protector outputs a switching value signal to the outside;
specifically, a data acquisition device and a device adopted by an alarm system are used, and one or a combination of several of selectors is selected according to actual application.
Two data acquisition devices store the data of gathering respectively in safety and control processor, after through communication module contrast, discover that the data is not the numerical value of normal work, and alarm system reports to the police according to actual conditions to start emergent action, if when monitoring jar internal pressure too high, open storage tank relief valve, carry out the pressure release.
According to the embodiment, the monitored data is subjected to double backup, so that the problems of data loss or discontinuity of one processing system can be prevented. Still be provided with the communication module who carries out data interchange between safety processor and control processor, can carry out communication and transmission to the data that two treater received, ensure the accuracy of data, when data acquisition device trouble, can in time discover the fault location.
Example 2
The embodiment provides a dual-redundancy safety monitoring control method for an LNG refueling ship in embodiment 1, which specifically includes the following steps:
firstly, respectively accessing data acquired by two data acquisition devices into a secure processor analog input module and a control processor analog input module;
secondly, converting the acquired data into decimal data by the security processor and the control processor, respectively storing the decimal data in the intermediate register A and the intermediate register B, and respectively storing the highest threshold values of the security processor and the control processor in the register G and the memory H;
comparing the data collected by the safety processor and the control processor with the highest threshold values in the register G and the memory H respectively;
fourthly, when the difference value in the register D is between the register E and the register F, the data of the register A < the data in the register G, the data of the register B < the data in the register H, and the system works normally;
and secondly, comparing the data in the register B and the data in the register H, controlling the processor alarm system to alarm, and when the data in the register A is larger than the data in the register G, the safety processor alarm system alarms and emergently cuts off the valve action.
Example 3
The embodiment is further improved on the basis of the embodiment 2, and specifically comprises the following steps: when the data received by the security processor and the control processor is between its lowest and highest thresholds:
fifthly, the control processor reads the data in the register A and stores the data in a continuous intermediate register C;
sixthly, the control processor calculates the difference value of the data in the register B and the register C through subtraction, and stores the calculated difference value in the intermediate register D; setting the lower limit value and the upper limit value of the allowable error value of the data acquired by the two data acquisition devices in a register E and a register F respectively;
step seven, comparing the difference value in the register D with the register E and the register F respectively
When the data in the register D is larger than the data in the register F or the data in the register D is smaller than the data in the register E, the industrial control computer or the touch screen displays that a fault occurs in the data acquisition device with abnormal data (for example, two groups of data of the pressure sensor are abnormal, and the fault of the pressure sensor is displayed), and the alarm system gives an alarm.
Example 4
The embodiment provides a method for safely monitoring and controlling the tank pressure in an LNG storage tank for embodiment 2, which specifically includes the following steps:
the method comprises the following steps that firstly, two pressure sensors arranged in a storage tank are respectively connected to a safety controller analog input module and a control processor analog input module through current signals of 0-20 MA;
step two, the safety processor and the control processor are programmable logic controllers integrated with the Ethernet communication function, and the processor stores the acquired data into an input mapping area;
step three, converting the collected data into decimal data by the CPU of the safety processor and the control processor respectively and storing the decimal data in continuous intermediate registers D100 and D200, setting the parameter of the maximum limit of the storage tank pressure of the safety processor in D112, and setting the maximum limit of the storage tank pressure of the control processor in D212;
step four, the control processor reads the data in the intermediate register D100 of the safety controller through the Ethernet and stores the data in a continuous intermediate register D220;
step five, the control processor calculates the difference value between D200 and D220 through subtraction, and stores the calculated value in an intermediate register D224, the control processor allows the error value low limit value to be set in a register D204, and allows the error value high limit value to be set in a register D208;
step six, when the collected and calculated data D204 is less than or equal to D224 is less than or equal to D208, the control processor judges that both the two sensors in the storage tank work normally;
and secondly, triggering a fault alarm output switch signal when the acquired and calculated data D224 is more than D208 or D224 is less than D204, and simultaneously displaying a fault alarm of the storage tank pressure sensor by the touch screen and the industrial personal computer and alarming by an alarm system.
And thirdly, when the pressure of the storage tank is normal, judging that D100 is greater than D112, controlling the alarm prompt of the processor, displaying that the pressure of the storage tank is high and pressure releasing is requested by a touch screen or an industrial personal computer, simultaneously controlling the alarm prompt of the alarm system of the processor, D200 is greater than D212, opening the pressure release valve of the storage tank, alarming by the alarm system, and closing the pressure release valve of the storage tank after the time delay of 30S (the specific time is actually set) from the release of gas to the setting range.
Example 5
This embodiment provides an LNG wharf boat system, and embodiment 1 ~ 3 can be used on this system, and ship supply mode, the ashore mode of unloading, the liquid feeding mode specifically is:
(1) the ship replenishment mode control method comprises the following steps:
a >: opening a manual valve;
b >: pressing a supply button of a filling machine ship;
c >: the safety processor automatically opens an upper/lower liquid inlet valve of the storage tank, a liquid supplementing gas phase port of the ship and a liquid supplementing liquid phase port of the ship, and the LNG ship is transported to carry out LNG water supply on the wharf ship through a pipeline;
d >: and when a filling machine stop button is pressed or the storage tank is detected to reach the limit height, stopping the ship supply, and returning to the standby state.
(2) The shore unloading mode control method comprises the following steps:
a >: opening a pressurizing opening of the tank car; opening a tank car return air port; carrying out tank car pressurization through a pressurizer;
b >: when the tank car pressure is greater than the storage tank pressure, the pressurization is stopped; opening a corresponding manual valve, pressing a shore unloading button, opening a corresponding starting valve by the system, and pre-cooling the unloading pump;
c >: after the pre-cooling of the unloading pump is completed, opening a ship shore connection pneumatic valve; opening an upper/lower liquid inlet valve; starting the unloading pump; the unloading pump conveys the LNG in the tank wagon to the storage tank through a pipeline;
d >: when the control processor detects a shore unloading stop signal or the liquid in the storage tank reaches the limit height, the unloading pump stops, and the shore connection pneumatic valve is closed after a period of time delay after the unloading pump stops; closing the upper/lower liquid inlet valve; and returning to the standby state.
(3) Liquid adding mode control method
a >: opening each manual valve on the liquid feeding loop;
b >: the liquid adding machine presses a liquid adding start button, the control processor opens a liquid inlet valve of the conveying pump and a liquid conveying valve of the conveying pump, opens a lower liquid inlet valve of the storage tank and a liquid adding air return valve, and the immersed pump performs precooling;
c >: when the precooling of the immersed pump is finished, the control processor opens a liquid outlet valve of the conveying pump, a liquid filling port and a gas returning port and adds liquid to other ships;
d >: when a stop button of the liquid adding machine is pressed or the storage tank is detected to reach the limit height, the immersed pump stops rotating, the corresponding valve is closed after the immersed pump stops rotating for a period of time, the liquid adding of the ship is stopped, and the ship enters a standby mode.
The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.