CN104833456B - An on-site detection device and method for a pressure sensor of a valve cooling system - Google Patents

Abstract

The invention discloses a kind of valve cooling system pressure sensor on-site detecting device, it includes pressure controller and pressure calibration, pressure controller includes electropneumatic pump, air accumulator, expansion drum, water tank, the output end of the electropneumatic pump is connected to the air inlet of expansion drum by air accumulator, the delivery port of water tank is connected to the water inlet of expansion drum, and the delivery port of expansion drum is connected to pressure calibration；The pressure calibration includes conveyance conduit, control valve, pressure sensor and draining valve, the delivery port of the expansion drum is connected to one end of conveyance conduit, draining valve is arranged at the other end of conveyance conduit, pressure sensor is installed on conveyance conduit, control valve is installed on the conveyance conduit between pressure sensor and expansion drum, and the pressure sensor includes pressure standard meter and table to be checked.The invention also discloses a kind of valve cooling system pressure sensor in-situ check and test method.The pressure sensor Site Detection high with reliability of full-automatic hydraulic pressure control can be achieved in the present invention.

Description

An on-site detection device and method for a pressure sensor of a valve cooling system

technical field

The invention relates to the technical field of high-voltage direct current transmission, in particular to an on-site detection device and method for a pressure sensor of a valve cooling system.

Background technique

The converter valve cooling system is a necessary auxiliary system for HVDC power transmission projects, and the converter valve cooling control system is an effective guarantee for reliable control and stable operation of the converter valve cooling system. The pipeline pressure of the valve cooling system of the direct current transmission project is used to provide power for the cooling water cycle, and the pressure sensor, as the signal acquisition unit of the converter valve cooling system, is an important part of it. By controlling the pressure between the valve towers, filter devices, water pump inlet and outlet in the cooling water cycle, the water cycle is guaranteed to be within the safe operation range of the system.

As the signal acquisition unit of the cooling control system of the diverter valve, the pressure sensor (instrument) is an important part of it. At present, some engineering pressure sensors in China sometimes have misjudgment of pressure abnormalities by the control system due to measurement errors, thereby incorrectly adjusting the pressure or causing outlet tripping accidents, and the overall reliability of the control system has declined. At present, it can only be diagnosed by removing the pressure sensor and sending it to a specific laboratory, using a pressure calibrator to compare the equivalent value of the air pressure and the water pressure collected by the sensor. The pressure calibrator is mainly composed of a manual pressure pump, a standard gauge and a gauge to be tested. It can be easily carried to the site for inspection, but the manual pressure pump cannot accurately control the air pressure, resulting in substandard verification process, and there is a risk of over-range damage to the meter head due to manual operation errors; data calculation and qualification judgment need to be carried out manually, which is inefficient , the reliability is not high. The pressure calibration bench can accurately test the pressure sensor, but it needs to take down the instrument to be tested during the power outage maintenance period and send it to the laboratory for testing, which takes a long time, and the cost of building the laboratory and the calibration bench is high.

In view of the urgent time for power outage maintenance, high precision of instruments and meters, and the verification process to be standardized, the development of this device can make up for the defects of the pressure calibrator and pressure calibrator, and can realize the portability of the detection device to the site of the converter station. , and can accurately detect the pressure sensor of the pure water cooling control system of the diverter valve when the time for power outage and maintenance is urgent. At the same time, the device adopts automatic air pressure control, which can precisely control the air pressure, standardize the verification process, and avoid the risk of over-range damage to the meter head due to manual operation errors; the device can automatically record and logically process measurement data to automatically determine Whether the pressure gauge is qualified, the efficiency is greatly improved compared with the pressure calibrator, and the reliability is higher.

Contents of the invention

In view of the deficiencies in the prior art, one of the purposes of the present invention is to provide a field detection device for the pressure sensor of the valve cooling system. The device can perform closed-loop control through the feedback of the pressure standard device (standard meter) according to the set detection node water pressure. Automatically adjust the air intake and exhaust of the electric pneumatic pump and solenoid valve, and realize precise control of the water pressure at the measurement node by controlling the air pressure, with higher reliability.

In order to achieve the above object, the technical scheme that the present invention takes is:

An on-site detection device for a pressure sensor of a valve cooling system, which includes a pressure controller and a pressure calibration platform, wherein:

The pressure controller includes an electric air pump, an air storage tank, an expansion tank, and a water tank. The output end of the electric air pressure pump is connected to the air inlet of the expansion tank through the air storage tank, and the water outlet of the water tank is connected to the inlet of the expansion tank. The water port, the water outlet of the expansion tank is connected to the pressure calibration table;

The pressure calibration platform includes a delivery pipeline, a control valve, a pressure sensor and a drain valve, the water outlet of the expansion tank is connected to one end of the delivery pipeline, the drain valve is arranged at the other end of the delivery pipeline, and the pressure sensor is installed on the delivery pipeline , the control valve is installed on the delivery pipeline between the pressure sensor and the expansion tank, and the pressure sensor includes a pressure standard device and a gauge to be tested.

The pressure controller further includes a first manual valve connected between the electric air pump and the air storage tank.

Two passages are arranged between the water tank and the expansion tank, wherein a second manual valve is installed on the first passage, and an electric valve is installed on the second passage.

A hydraulic driver is installed between the expansion tank and the delivery pipeline.

The control valve includes a fifth manual valve and a third manual valve, a first solenoid valve and a fourth manual valve which are sequentially connected in series on the conveying pipeline. Both ends of the first solenoid valve are connected through a bypass conveying pipeline, and the fifth A manual valve is installed on the bypass delivery pipeline.

The field detection device of the pressure sensor of the valve cooling system further includes a detection terminal, and the detection terminal includes a data acquisition unit and a receiving terminal, and the output ends of the pressure standard device and the meter to be inspected are all connected to the input end of the data acquisition unit. The output end of the data acquisition unit is connected to the receiving terminal.

Another object of the present invention is to provide an on-site detection method for the pressure sensor of the valve cooling system, which can automatically adjust the electropneumatic pump and electromagnetic The air intake and exhaust of the valve can be precisely controlled by controlling the air pressure to realize the precise control of the water pressure at the measurement node, which has higher reliability.

In order to achieve the above object, the technical scheme that the present invention takes is:

A method for on-site detection of a valve cooling system pressure sensor on-site detection device, which includes the following steps:

Step 1. Set the detection node according to the pressure range of the meter to be tested;

Step 2. Turn on the pressure controller and adjust the water pressure on the delivery pipeline through the electric pneumatic pump. When the water pressure on the delivery pipeline reaches the pressure value set by the detection node, obtain the pressure error value. When the pressure error value is not greater than At zero time, perform the operation of step 3, otherwise, perform step 4, wherein the pressure error value is the difference between the pressure measurement error and the pressure parameter of the gauge to be tested, and the pressure measurement error is the pressure measurement value of the pressure standard and the absolute value of the difference between the pressure measurement value of the meter to be checked, the pressure parameter of the meter to be checked is the product between the pressure measurement range of the meter to be checked and the pressure measurement accuracy of the meter to be checked, the pressure parameter of the meter to be checked is The pressure measurement range and the pressure measurement accuracy of the meter to be tested are factory parameters;

Step 3, obtain the current error value, when the current error value is not greater than zero, the meter to be checked is qualified, otherwise, perform step 4, wherein the current error value is the difference between the current measurement error and the current parameter of the meter to be checked value, the current measurement error is the absolute value of the difference between the current measurement value of the pressure standard device and the current pressure measurement value of the meter to be checked, and the current parameter of the meter to be checked is the current measurement range of the meter to be checked and The product of the current measurement accuracy of the meter under inspection, the current measurement range of the meter under inspection and the current measurement accuracy of the meter under inspection are factory parameters;

Step 4, the table to be inspected is unqualified.

There are a plurality of detection nodes, and if there is a pressure error value or a current error value of a detection node greater than zero among the plurality of detection nodes, the meter to be inspected is unqualified.

When detecting the multiple detection nodes, first increase the water pressure on the delivery pipeline through the electric pneumatic pump to perform upstroke detection on the multiple detection nodes one by one, and then reduce the water pressure on the delivery pipeline through the electric pneumatic pump. The plurality of detection nodes perform downstroke detection one by one, and the upstroke detection and downstroke detection respectively perform at least three detections.

There are seven detection nodes, and the pressure values set by the seven detection nodes correspond to 0%, 20%, 40%, 50%, 60%, 80%, and 100% of the pressure range of the gauge to be tested respectively. When multiple gauges to be inspected with different pressure ranges are set on the device, the multiple gauges to be inspected shall be tested one by one.

Compared with prior art, the beneficial effect of the present invention is:

1. Realize on-site detection, which can make up for the defects of pressure calibrator and pressure calibrator, can carry the detection device to the site of the converter station easily, and can cool the converter valve with pure water when the time for power outage maintenance is urgent The pressure sensor of the control system performs accurate detection.

2. A detection method with higher reliability. Detect the intuitive water pressure value and the current value transmitted by the sensor, and at the same time detect the upstroke of the water pressure rise and the downstroke of the water pressure drop to improve the reliability of the detection. It takes about 15 minutes to complete a detection on average, saving Detection time.

3. Fully automatic water pressure control. According to the set measuring node water pressure, the device can perform closed-loop control through the feedback of the standard meter, automatically adjust the intake and exhaust of the pressure pump and solenoid valve, and realize the precise control of the measuring node water pressure by controlling the air pressure.

Description of drawings

Fig. 1 is the structural representation of a kind of on-the-spot detection device of valve cooling system pressure sensor of the present invention;

Fig. 2 is a schematic structural diagram of a monitoring terminal;

Fig. 3 is the structural representation of closed-loop circuit;

Fig. 4 is a flowchart of an on-site detection method for a pressure sensor of a valve cooling system according to the present invention.

Explanation of reference signs: 10. Pressure controller; 20. Pressure calibration platform; 1. Electric pneumatic pump; 11. First manual valve; 2. Gas storage tank; 21. Pressure switch; 3. Expansion tank; 4. Water tank ;41, the second manual valve; 42, the electric valve; 5, hydraulic drive; 61, the third manual valve; 62, the first solenoid valve; 63, the fourth manual valve; 64, the fifth manual valve; 7, Pressure standard device; 81, the meter to be checked; 8n, the meter to be checked; 91, the sixth manual valve; 92, the second solenoid valve.

detailed description

The present invention will be further described below in combination with specific embodiments.

Please refer to Figure 1, an on-site detection device for a pressure sensor of a valve cooling system, which includes a pressure controller 10 and a pressure calibration platform 20, wherein: the pressure controller 10 includes an electric pneumatic pump 1, an air storage tank 2, and an expansion tank 3. Water tank 4, the output end of the electric pneumatic pump 1 is connected to the air inlet of the expansion tank 3 through the air storage tank 2, the water outlet of the water tank 4 is connected to the water inlet of the expansion tank 3, and the water outlet of the expansion tank 3 is passed through the water pressure. The driver 5 is connected to the pressure calibration platform 20 , a first manual valve 11 is set between the electric pneumatic pump 1 and the gas storage tank 2 , and a pressure switch 21 is set between the gas storage tank 2 and the expansion tank 3 . Two passages are arranged between the water tank 4 and the expansion tank 3, wherein a second manual valve 41 is installed on the first passage, and an electric valve 42 is installed on the second passage.

The pressure calibration platform 20 includes a delivery pipeline, a control valve, a pressure sensor and a drain valve. The water outlet of the expansion tank 3 is connected to one end of the delivery pipeline, the drain valve is arranged at the other end of the delivery pipeline, and the pressure sensor is installed on the delivery pipeline. The valve is installed on the delivery pipeline between the pressure sensor and the expansion tank 3. The pressure sensor includes a pressure standard device 7 and a plurality of gauges to be checked, which are respectively gauges to be checked 81,..., gauges to be checked 8n, where n is greater than 1 positive integer. The pressure standard device 7 adopts a 0.05 grade digital pressure gauge to cooperate with a standard pressure gauge or an intelligent pressure module to realize the pressure standard required by the system.

The control valve includes a fifth manual valve 64 and a third manual valve 61, a first solenoid valve 62 and a fourth manual valve 63 connected in series on the delivery pipeline in sequence. Both ends of the first solenoid valve 62 are connected through a bypass delivery pipeline. Five manual valves 64 are installed on the bypass delivery pipeline, and the drain valve is provided with a sixth manual valve 91 and a second solenoid valve 92 .

Please refer to Figure 2. The on-site detection device for the pressure sensor of the valve cooling system further includes a detection terminal. The detection terminal includes a data acquisition unit and a receiving terminal. The data acquisition unit is used as an information acquisition device. The output signals of the device 7 and the meter to be checked (including the current signal from the sensor side and the pressure signal from the transmission side) are transmitted to the receiving terminal. The receiving terminal can be a PC terminal, a tablet terminal, a mobile phone terminal, etc. These receiving terminals can also communicate with the printing and fax all-in-one machine through a communication link (wired network or wireless network) to realize printing and transmission functions. The detection terminal is developed for windows system and ios system, using LabVIEW graphical language, and the functions that can be realized include: internal registered user login; parameter setting; issuing air pressure measurement instructions; recording, calculating standard tables and tables to be inspected; historical record query .

Please refer to FIG. 3 , the water pressure can be precisely adjusted according to the pressure signal fed back by the pressure standard device 7 . The pressure signal fed back by the pressure standard device 7 (corresponding to the water pressure of the delivery pipeline) and the control parameter (that is, the pressure value set by the detection node) are differentially calculated and then amplified, and then the electropneumatic pump 1 and the first solenoid valve 62 for control, for example, when the feedback pressure signal of the pressure standard device 7 is less than the control parameter, the electric servo pressure creation function of the electric pneumatic pump 1 is used to increase the pressure on the delivery pipeline through the first solenoid valve 62 to increase the pressure of the pressure standard device 7 Feedback pressure signal, on the contrary, then use the return check function of electric pneumatic pump 1 to reduce water pressure, so as to reduce the pressure signal fed back by pressure standard device 7; It should be noted that if the water pressure of the delivery pipeline is zero, then The electropneumatic pump 1 does not work, just open the second electromagnetic valve 92 and get final product.

The device can be developed in view of the urgent time for maintenance due to power outages, high precision requirements for instruments and meters, and the verification process to be standardized. The device can be easily carried to the site and can accurately detect the pressure sensor. At the same time, for the non-standard detection of the pressure sensor of the valve cooling system, a standardized detection method is formulated and integrated into the detection device through software.

The on-site detection method of the pressure sensor of the valve cooling system can be realized through the automatic calibration system. The automatic calibration system collects, analyzes and calculates water pressure data, including a current detection unit and a pressure sensor power supply unit (which can measure two-wire and four-wire pressure sensors), as shown in Figure 4, which specifically includes the following step.

Step 1: Turn on the pressure controller, set 7 detection nodes, including P=0 and P=FS (full scale) two points are m=1 and m=7 respectively, and the remaining five detection nodes are 20 %FS, 40%FS, 50%FS, 60%FS, 80%FS;

Step 2: Open the drain valve, close the drain valve when the water pressure is 0, perform zero point detection at the detection node m=1, and collect the water pressure value and current value of the pressure standard device;

Step 3: Through the electric servo pressure creation function of the pressure controller, increase the water pressure to the next detection node m (the water pressure is not zero), start the upstroke detection, and proceed to steps 4 and 5;

Step 4: The automatic calibration system analyzes the data and judges if it satisfies: P(m)=|P _m (measured value)-P _m (standard value)|-P _m (range)*P _m (accuracy)≤0 , then proceed to step 4, otherwise, proceed to step 10, wherein, P(m) is the pressure error value of the detection node m, _Pm (measured value) is the pressure measurement value of the meter to be tested, and _Pm (standard value) is The pressure measurement value of the pressure standard device, P _m (range) and P _m (accuracy) are respectively the pressure measurement range value and the pressure measurement accuracy value in the factory parameters (ie known quantity) of the meter to be tested.

Step 5: The automatic calibration system analyzes the data and judges that if it is satisfied: I(m)=|I _m (measured value)-I _m (standard value)|-I _m (range)*I _m (accuracy)≤0 , then proceed to step 5, otherwise, proceed to step 10, wherein, I( _m ) is the current error value of the detection node m, Im (measured value) is the current measured value of the meter to be checked, and _Im (standard value) is The current measurement value of the pressure standard device, I _m (range) and _Im (accuracy) are respectively the current measurement range value and the current measurement precision value in the factory parameter (ie known quantity) of the meter to be tested;

Step 6: If m is not equal to 7, repeat steps 3, 4, and 5, otherwise, execute step 7;

Step 7: If m=7, use the back-check function of the pressure controller to reduce the water pressure to the next detection node m, start the down-stroke detection, and proceed to steps 4 and 5;

Step 8: If m is not equal to 1, repeat steps 7, 4, and 5;

Step 9: Perform 3 times of upstroke detection and 3 times of downstroke detection and all meet the judgment conditions, then it is judged that the pressure sensor is qualified.

Step 10: If the result detected by any detection node (that is, steps 4 and 5) does not meet the determination condition, it is determined that the pressure sensor is unqualified.

The above detailed description is a specific description of the feasible embodiment of the present invention. This embodiment is not used to limit the patent scope of the present invention. Any equivalent implementation or change that does not deviate from the present invention should be included in the patent scope of this case. middle.

Claims (7)

1. a kind of valve cooling system pressure sensor on-site detecting device, it is characterised in that it includes pressure controller (10) and pressure Power checking table (20), wherein：

The pressure controller (10) includes electropneumatic pump (1), air accumulator (2), expansion drum (3), water tank (4), described electronic The output end of pulsometer (1) is connected to the air inlet of expansion drum (3) by air accumulator (2), and the delivery port of water tank (4) is connected to swollen The water inlet of swell (3), the delivery port of expansion drum (3) is connected to pressure calibration (20), the electropneumatic pump (1) and gas storage It is connected between tank (2) by first manual valve (11), two paths is set between the water tank (4) and expansion drum (3), wherein It is provided with first path on the second hand-operated valve (41), alternate path and motor-driven valve (42) is installed；

The pressure calibration (20) includes conveyance conduit, control valve, pressure sensor and draining valve, the expansion drum (3) Delivery port is connected to one end of conveyance conduit, and draining valve is arranged at the other end of conveyance conduit, and pressure sensor is installed on conveying On pipeline, control valve is installed on the conveyance conduit between pressure sensor and expansion drum (3), and the pressure sensor includes pressure Power standard (7) and table to be checked, the pressure sensor are set by the pressure signal for feeding back pressure standard meter (7) with table to be checked Fixed pressure value carries out difference operation and is amplified, and is conveyed with controlling electropneumatic pump (1) and the first magnetic valve (62) to adjust The hydraulic pressure of pipeline, the control valve includes the 5th hand-operated valve (64) and is sequentially connected in series in the 3rd hand-operated valve on conveyance conduit (61), the first magnetic valve (62) and the 4th hand-operated valve (63), the two ends of first magnetic valve (62) pass through a bypass delivery pipe Road is connected, and the 5th hand-operated valve (64) is installed on the bypass conveyance conduit.

2. valve cooling system pressure sensor on-site detecting device according to claim 1, it is characterised in that the expansion drum (3) between conveyance conduit and install a hydraulic actuator (5).

3. valve cooling system pressure sensor on-site detecting device according to claim 1, it is characterised in that the cold system of the valve System pressure sensor on-site detecting device further comprises detection terminal, and the detection terminal includes data acquisition unit and reception The output end of terminal, the pressure standard meter (7) and table to be checked is all connected to the input of data acquisition unit, and the data are adopted The output end of collection unit is connected to receiving terminal.

4. the valve cooling system pressure sensor on-site detecting device according to claim any one of 1-3 carries out Site Detection Method, it is characterised in that it comprises the following steps：

Step 1, the set pressure span detection node according to table to be checked；

Step 2, Opening pressure controller (10), adjust the hydraulic pressure on conveyance conduit, when the conveying by electropneumatic pump (1) When hydraulic pressure on pipeline reaches the pressure value of detection node setting, pressure error value is obtained, when pressure error value is not more than zero, The operation of step 3 is performed, conversely, step 4 is performed, wherein, the pressure error value is pressure measurement errors and the pressure of table to be checked The difference of force parameter, the pressure measurement errors are the pressure measuring value of pressure standard meter (7) and the pressure measuring value of table to be checked Between difference absolute value, the pressure parameter of the table to be checked is that the pressure measxurement range of table to be checked and the pressure of table to be checked are surveyed Product between accuracy of measurement, the pressure measxurement range of table to be checked and the pressure measurement accuracy of table to be checked are parameter of dispatching from the factory, described defeated The hydraulic pressure on pipeline is sent to be obtained by the pressure measuring value of pressure standard meter (7)；

Step 3, acquisition current error value, when current error value is not more than zero, then the table to be checked is qualified, conversely, performing step 4, wherein, the current error value is current measurement errors and the difference of the current parameters of table to be checked, the current measurement errors The absolute value of current measurement value for pressure standard meter (7) and the difference between the current stresses measured value of table to be checked, it is described to treat It is the product between the current measurement range of table to be checked and the current measurement precision of table to be checked to examine the current parameters of table, table to be checked The current measurement precision of current measurement range and table to be checked is parameter of dispatching from the factory；

Step 4, the table to be checked are unqualified.

5. method according to claim 4, it is characterised in that the detection node is multiple, in the plurality of detection node Pressure error value or current error value if there is a detection node are more than zero, then the table to be checked is unqualified.

6. method according to claim 5, it is characterised in that when being detected to the plurality of detection node, pass through first Hydraulic pressure on electropneumatic pump (1) increase conveyance conduit carries out up stroke detection one by one, Ran Houzai to the plurality of detection node Reduce down stroke detection of the hydraulic pressure to the progress of the plurality of detection node one by one on conveyance conduit, institute by electropneumatic pump (1) State up stroke detection and down stroke detection carries out at least three times detections respectively.

7. method according to claim 6, it is characterised in that the detection node is seven, and seven detection nodes are set Fixed pressure value corresponds to 0%, 20%, 40%, 50%, 60%, 80%, the 100% of meter pressure range to be checked respectively, works as delivery pipe When the table to be checked of multiple different pressures ranges is set on road, the plurality of table to be checked is detected one by one.