Temperature control device based on gas pressure regulating station and gas pressure regulating station outlet temperature adjusting method

Abstract

The application discloses a temperature control device based on a gas pressure regulating station and a gas pressure regulating station outlet temperature adjusting method. The device comprises a primary pressure regulator and a secondary pressure regulator. The primary pressure regulator is connected with a high-pressure gas inlet pipeline. A first temperature detector, a first flow detector, a first heater and a first pressure detector are arranged on the high-pressure gas inlet pipeline. A gas output pipeline of the primary pressure regulator is divided into at least two branch pipes through a second pressure detector and a second temperature detector. The branch pipes are directly output to the outside of the pressure regulating station, and / or sequentially pass through a second flow detector, a second heater, a secondary pressure regulator, a third pressure detector and a third temperature detector, and then are connected with a downstream pipeline. All the temperature detectors, the flow detectors, the heaters and the pressure detectors are connected with a control system. The device can automatically match a heat load and avoid energy waste.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of natural gas temperature regulation, and particularly relates to a temperature control device based on a gas pressure regulating station and a gas pressure regulating station outlet temperature regulation method. BACKGROUND

[0002] With the popularization of gas application and the gradual deepening of the requirement of gas replacing coal by the country, more and more towns need to increase gas pressure regulating stations. The most typical pressure regulating station is that high pressure or sub-high pressure is input into the station, and after metering and pressure regulating, sub-high pressure or medium pressure is output from the station to supply the town gas pipe network. In the actual operation process, the flow rates of the sub-high pressure output and the medium pressure output of the pressure regulating station are not in a fixed ratio, so that the pressure regulating station cannot accurately control the heat load, resulting in heat waste. For example, in some stations, the flow rate of the sub-high pressure output is relatively large, and the flow rate of the medium pressure output is relatively small. At this time, after heat exchange by the heater, the temperature of the sub-high pressure output just reaches the set value of 0℃ or below, while the temperature of the medium pressure output has reached 20℃ or above, which obviously exceeds the demand range of the gas factory, resulting in a large amount of energy waste. Under the current background of energy saving and carbon reduction, this is an unreasonable phenomenon.

[0003] In the operation process of the gas pressure regulating station, the outlet pressures and flow rates of the branches often dynamically change with time. In the process of gas pressure regulation, heat needs to be absorbed due to the reduction of gas pressure. At this time, if heat is not supplemented in time, the gas cannot obtain enough heat from the environment, resulting in a temperature drop. When the temperature is lower than the set value, the downstream equipment may be affected. The traditional process scheme adopts a quantitative heating mode, which cannot well match the real-time conditions of the gas, resulting in uneven outlet temperature. Even in order to ensure the output temperature of a certain road, the temperature of other branches will exceed the upper limit, causing energy waste. SUMMARY

[0004] The temperature control device provided by the application is used to solve the problem that the heating equipment and the output flow rate are not matched due to the unstable outlet pressures and flow rates of the branches of the gas pressure regulating station. Through the overall combination of the field detection equipment and the heating equipment, the accurate control of the outlet temperature of the gas is realized, the outlet temperature is prevented from being too high or too low, and energy waste is also reduced. The temperature control device based on the gas pressure regulating station automatically matches the heat load required by the outlet flow rate. The real-time heat demand is automatically calculated, and the output heat load of the heating device is adjusted in real time, so that the outlet temperature is controlled within a reasonable range and energy waste is avoided.

[0005] The temperature control device based on the gas pressure regulating station of the application comprises a primary pressure regulator and a secondary pressure regulator for regulating the gas pressure, the gas inlet of the primary pressure regulator is connected with a high-pressure gas inlet pipeline, the high-pressure gas inlet pipeline is sequentially provided with a first temperature detector, a first flow detector, a first heater and a first pressure detector along the gas conveying direction, the gas output pipeline of the primary pressure regulator sequentially passes through a second pressure detector and a second temperature detector, and then: (1) a branch pipe is branched off as a gas output pipeline (for example, a next-high-pressure gas output pipeline) to convey the gas to outside the pressure regulating station, and / or (2) a branch pipe sequentially passes through a second flow detector, a second heater, a secondary pressure regulator, a third pressure detector and a third temperature detector, and is connected with a downstream pipeline, and the first temperature detector, the first flow detector, the first heater, the first pressure detector, the second pressure detector, the second temperature detector, the second flow detector, the second heater, the third pressure detector and the third temperature detector are connected with a control system.

[0006] Further, the control system is an automatic control system, and the control system collects the temperature, pressure and flow signals of the first temperature detector, the first flow detector, the first pressure detector, the second pressure detector, the second temperature detector, the second flow detector, the third pressure detector and the third temperature detector to control the heating power of the first heater and the second heater, so as to adjust the outbound temperature of the gas to a reasonable range in real time.

[0007] Further, a first manifold for stabilizing the gas flow is arranged on the high-pressure gas inlet pipeline between the first temperature detector and the first flow detector.

[0008] Further, the gas output pipeline after the second temperature detector is branched into a plurality of branch pipes through a second manifold.

[0009] Further, a third manifold is arranged on the branch pipe after the third temperature detector.

[0010] Further, the first heater and the second heater are gas electric heaters.

[0011] The method for adjusting the outbound temperature of the gas pressure regulating station by using the temperature control device of the application comprises the following steps:

[0012] The high-pressure gas passes through the first temperature detector (optionally enters the first manifold, and the gas output from the first manifold), passes through the first flow detector, enters the first heater for the first temperature rise, and the heated gas passes through the first pressure detector, enters the primary pressure regulator for the first pressure reduction. The reduced pressure gas passes through the second pressure detector and the second temperature detector in turn (optionally enters the second manifold, and the medium-pressure gas in the second manifold is output), and is directly output to the outside of the pressure regulating station as the sub-high-pressure gas, or includes another route that passes through the second flow detector, enters the second heater for the second temperature rise, and the heated gas enters the secondary pressure regulator for the second pressure reduction to obtain the medium-pressure gas. The second reduced pressure gas passes through the third pressure detector and the third temperature detector in turn (optionally enters the third manifold, and the medium-pressure gas in the third manifold is output) and is output to the outside of the pressure regulating station.

[0013] 1. Primary pressure regulating temperature control function

[0014] In the gas pressure regulating process, the control system obtains the inlet gas temperature T1 through the first temperature detector, obtains the pressure P1 before the primary pressure regulator (generally 2.5-6.0 MPa) through the first pressure detector, obtains the temperature T2 after the primary pressure regulator through the second temperature detector, obtains the pressure P2 after the primary pressure regulator (generally 1.2-1.45 MPa) through the second pressure detector, and obtains the instantaneous flow rate F1 before the primary pressure regulator through the first flow detector. In order to ensure that the outlet temperature of the primary pressure regulator reaches a certain temperature T2, for example, 2-8°C, further 4-8°C, and preferably about 5°C, the temperature T1' that the gas temperature before the primary pressure regulator should reach should be:

[0015] Formula 1: T1'=T2-(μj*(P2-P1))

[0016] In the formula, T1' is the temperature before the primary pressure regulator, in °C.

[0017] μj is the natural gas Joule-Thomson coefficient (°C / MPa, which can be found in relevant literature).

[0018] P1 is the pressure before the primary pressure regulator (MPa, absolute pressure).

[0019] P2 is the pressure after the primary pressure regulator (MPa, absolute pressure).

[0020] T2 is the natural gas temperature after the primary pressure regulator (°C).

[0021] Through the calculation of Formula 1, the temperature value that the primary pressure regulator before should at least reach to ensure that the outlet temperature of the primary pressure regulator reaches T2, for example, 2-8°C, further 4-8°C, and further for example, 5°C, can be calculated. Then, the theoretical electric heater power P is calculated through the temperature difference between the inlet and outlet of the first heater.

[0022] Formula 2: P = (F1*P*C*(T1'-T1)) / (k*3600)

[0023] In the formula: T1' - temperature before the first pressure regulator (℃)

[0024] F1 - instantaneous flow before the first pressure regulator (Nm 3 / h)

[0025] P - standard density of natural gas (value is 0.75 Kg / Nm 3 )

[0026] C - specific heat capacity of natural gas (value is 2.156 KJ / (Kg*K))

[0027] T1 - temperature of natural gas entering the station (℃)

[0028] k - electric heater conversion and heat exchange coefficient (value is 0.85-0.95).

[0029] Through the calculation of Formula 2, the power of the first heater required to ensure that the outlet temperature of the first pressure regulator reaches the set value can be obtained, and then the power of the first heater is adjusted to the appropriate position through the output of the control system. The control process is dynamic, and the power of the first heater is adjusted at any time with the adjustment of the inlet flow, to ensure that the temperature of the gas after the first pressure regulation can still be maintained near the set value after the inlet flow changes, avoiding the phenomenon of over-temperature or low-temperature.

[0030] 2. Secondary pressure regulation temperature control function

[0031] The control system obtains the pressure P3 after the second pressure regulator (generally 0.2-0.35 MPa) through the third pressure detector, obtains the temperature T3 after the second pressure regulator through the third temperature detector, and obtains the instantaneous flow F2 before the second pressure regulator through the second flow detector. In order to ensure that the outlet temperature of the second pressure regulator reaches a certain temperature (for example, 4-8℃, further for example, 5℃), the temperature T1" that the gas temperature before the second pressure regulator should reach should be:

[0032] Formula 3: T1" = T3 - (μj*(P3-P2))

[0033] In the formula: T1" - temperature before the second pressure regulator (℃)

[0034] μj - Joule-Thomson coefficient of natural gas (℃ / MPa, which can be found in relevant literature)

[0035] P2 - pressure before the second pressure regulator (MPa, absolute pressure)

[0036] P3 - pressure after the second pressure regulator (MPa, absolute pressure)

[0037] T3 - Natural gas temperature after the secondary pressure regulator (°C).

[0038] By calculation of formula 3, the temperature value before the secondary pressure regulator that should be reached at least can be calculated when ensuring the outlet temperature of the secondary pressure regulator reaches, for example, 4-8°C, further for example 5°C, and then the theoretical function rate P' of the second heater can be calculated by the temperature difference between the inlet and outlet of the second heater:

[0039] Formula 4: P' = (F2*P*C*(T1"-T2)) / (k*3600)

[0040] In the formula: T1" - Temperature before the secondary pressure regulator (°C)

[0041] F2 - Instantaneous flow before the secondary pressure regulator (Nm 3 / h)

[0042] P - Standard density of natural gas (value taken as 0.75 Kg / Nm 3 )

[0043] C - Specific heat capacity of natural gas (value taken as 2.156 KJ / (Kg*K))

[0044] T2 - Natural gas temperature after the primary pressure regulator (°C)

[0045] K - Electric heater conversion and heat exchange coefficient (value taken as 0.85-0.95).

[0046] By calculation of formula 4, the power of the second heater required to ensure the outlet temperature of the secondary pressure regulator reaches the set value can be obtained, and then the power of the second heater is adjusted to an appropriate position by the output of the control system.

[0047] In actual operation, if the power control fails and the outlet temperature of the pressure regulator is lower than the set value, the temperature control override mode is entered, and the control system can use the temperature T2 after the primary pressure regulator or the temperature T3 after the secondary pressure regulator for override control. When the calculation output by formula 2 or formula 4 cannot meet the temperature set value (for example, 0°C) after pressure regulation, the control mode of the control system is forcibly switched to the temperature regulation mode (the switching of the control mode is realized by switching the control algorithm in the control system), that is, the output signal of the control system is forcibly increased to improve the heating power, so as to increase the temperature T2 or T3 after the pressure regulator, and avoid the phenomenon of low or high outlet temperature due to power control failure, thereby improving the availability of the control system. At the same time, when the temperature T2 or T3 after the pressure regulator returns to the normal set value (for example, 10°C), the control system will automatically switch the control mode and return to the power control mode again to improve the control accuracy.

[0048] In the present application, "optionally" means with or without, or performing or not performing the process step immediately following the term.

[0049] By effectively controlling the temperature before and after the primary and secondary pressure regulators, the phenomenon of uneven outlet temperature of the gas pressure regulating station is solved, and the waste of energy is greatly reduced.

[0050] The beneficial effects of the present application are:

[0051] (1) The device of the present application can dynamically change the power of the first and second heaters with the size of the inlet flow, and adjust the heating power in real time, so that the control is more refined.

[0052] (2) By effectively controlling the inlet temperature of the primary and secondary pressure regulators, the phenomenon of excessively low outlet temperature of the primary and secondary pressure regulators is avoided, the possibility of ice blockage of the pressure regulating equipment is effectively avoided, and the safety of the pressure regulating equipment is significantly improved.

[0053] (3) The device can effectively avoid dry burning of the first and second heaters, effectively reduce power consumption, and reduce carbon consumption under the same working conditions.

[0054] In summary, the device of the present application has the advantages of more refined control, energy saving and consumption reduction, and safe and stable control process. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a schematic view of a temperature control device based on a gas pressure regulating station.

[0056] MARKED FOR EXPLANATION:

[0057] 1-primary pressure regulator, 2-secondary pressure regulator, 3-first temperature detector, 4-first flow detector, 5-first heater, 6-first pressure detector, 7-second pressure detector, 8-second temperature detector, 9-second flow detector, 10-second heater 10, 11-third pressure detector, 12-third temperature detector, 13-control system, 14-first manifold, 15-second manifold, 16-third manifold;

[0058] L1-high pressure inlet pipeline, L2-branch pipe. DETAILED DESCRIPTION

[0059] The present application will be further described below with reference to the accompanying drawings.

[0060] As Figure 1As shown, the temperature control device based on gas pressure regulating station of the present application comprises a first pressure regulator 1 and a second pressure regulator 2 for regulating the gas pressure, the gas inlet of the first pressure regulator 1 is connected with a high-pressure gas inlet pipeline L1, the high-pressure gas inlet pipeline L1 is sequentially provided with a first temperature detector 3, a first flow detector 4, a first heater 5 and a first pressure detector 6 along the gas conveying direction, the gas output pipeline of the first pressure regulator 1 is divided into at least two branch pipes (for example, 2-6, preferably 2-4, more preferably 2) after sequentially passing through a second pressure detector 7 and a second temperature detector 8, the branch pipe L2: (1) as a gas output pipeline (for example, a pipeline for outputting the gas with a secondary high pressure) for conveying the gas to the outside of the pressure regulating station, and / or (2) is connected with a downstream pipeline after sequentially passing through a second flow detector 9, a second heater 10, a second pressure regulator 2, a third pressure detector 11 and a third temperature detector 12, the first temperature detector 3, the first flow detector 4, the first heater 5, the first pressure detector 6, the second pressure detector 7, the second temperature detector 8, the second flow detector 9, the second heater 10, the third pressure detector 11 and the third temperature detector 12 are connected with a control system 13.

[0061] The control system 13 is an automatic control system, the control system 13 collects the temperature, pressure and flow signals of the first temperature detector 3, the first flow detector 4, the first pressure detector 6, the second pressure detector 7, the second temperature detector 8, the second flow detector 9, the third pressure detector 11 and the third temperature detector 12 for controlling the heating power of the first heater 5 and the second heater 10, so as to adjust the outbound temperature of the gas to a reasonable range in real time.

[0062] The control system 13 is wirelessly connected or connected through wires with the first temperature detector 3, the first flow detector 4, the first heater 5, the first pressure detector 6, the second pressure detector 7, the second temperature detector 8, the second flow detector 9, the second heater 10, the third pressure detector 11 and the third temperature detector 12.

[0063] A first manifold 14 for stabilizing the gas flow can be arranged on the high-pressure gas inlet pipeline between the first temperature detector 3 and the first flow detector 4.

[0064] The gas output pipeline after the second temperature detector is divided into a plurality of branch pipes through a second manifold 15, for example, the branch pipes as the gas output pipeline (for example, the pipeline for outputting the gas with a secondary high pressure) for conveying the gas to the outside of the pressure regulating station, and / or the branch pipes as the pipeline connected with the downstream pipeline after sequentially passing through the second flow detector 9, the second heater 10, the second pressure regulator 2, the third pressure detector 11 and the third temperature detector 12.

[0065] A third manifold 16 is arranged on the branch pipe after the third temperature detector.

[0066] The first heater 5 and the second heater 10 are gas electric heaters.

[0067] The process of adjusting the gas temperature using the temperature control device of the present application comprises:

[0068] The high-pressure gas enters the first manifold 14 after passing through the first temperature detector 3, and the gas output from the first manifold 14 enters the first heater 5 after passing through the first flow detector 4 to be heated for the first time, and the heated gas enters the primary pressure regulator 1 to be depressurized for the first time after passing through the first pressure detector 6, and the depressurized gas enters the second manifold 15 after passing through the second pressure detector 7 and the second temperature detector 8 in turn, and the gas output from the second manifold 15 is divided into at least two paths, one of which is directly output as a sub-high-pressure gas to the outside of the pressure regulating station, or one of which enters the second heater 10 to be heated for the second time after passing through the second flow detector 9, and the heated gas enters the secondary pressure regulator 2 to be depressurized for the second time to obtain medium-pressure gas, and the gas depressurized for the second time enters the third manifold 16 after passing through the third pressure detector 11 and the third temperature detector 12 in turn, and the medium-pressure gas of the third manifold 16 is output to the outside of the pressure regulating station.

[0069] 1. Primary pressure regulating temperature control function

[0070] In the process of gas pressure regulation, the control system obtains the inlet gas temperature T1 through the first temperature detector 3, obtains the pressure P1 before the primary pressure regulator through the first pressure detector 6, obtains the temperature T2 after the primary pressure regulator through the second temperature detector 8, obtains the pressure P2 after the primary pressure regulator through the second pressure detector 7, and obtains the instantaneous flow F1 before the primary pressure regulator through the first flow detector 4, in order to ensure that the outlet temperature of the primary pressure regulator reaches the set temperature of about 5°C, then the temperature T1' that the gas temperature before the primary pressure regulator should reach should be:

[0071] Formula 1: T1'=T2-(μj*(P2-P1))

[0072] In the formula: T1'— temperature before the primary pressure regulator (°C)

[0073] μj— natural gas Joule-Thomson coefficient (°C / MPa, which can be found in relevant literature)

[0074] P1— pressure before the primary pressure regulator (MPa, absolute pressure)

[0075] P2— pressure after the primary pressure regulator (MPa, absolute pressure)

[0076] T2— natural gas temperature after the primary pressure regulator (°C).

[0077] Through the calculation of formula 1, the temperature value that should be reached at least before the primary pressure regulator can be calculated when the outlet temperature of the primary pressure regulator reaches 5℃, and then the theoretical electric heater function rate P can be calculated through the temperature difference between the inlet and outlet of the first heater: formula 2: P=(F1*ρ*C*(T1'-T1)) / (k*3600)

[0078] In the formula: T1' - temperature before the primary pressure regulator (℃)

[0079] F1 - instantaneous flow before the primary pressure regulator (Nm 3 / h)

[0080] ρ - standard density of natural gas (the value is 0.75 Kg / Nm 3 )

[0081] C - specific heat capacity of natural gas (the value is 2.156 KJ / (Kg*K))

[0082] T1 - inlet temperature of natural gas (℃)

[0083] k - electric heater electric heating conversion and heat exchange coefficient (the value is 0.85-0.95).

[0084] Through the calculation of formula 2, the power of the first heater required to ensure that the outlet temperature of the primary pressure regulator reaches the set value can be obtained, and then the power of the first heater is adjusted to an appropriate position through the output of the control system. The control process is dynamic, and the power of the first heater is adjusted at any time with the adjustment of the inlet flow, so that the temperature of the gas after the primary pressure regulation can still be maintained near the set value after the inlet flow changes, avoiding the phenomenon of over-temperature or low-temperature.

[0085] 2. Secondary pressure regulation temperature control function

[0086] The control system obtains the pressure P3 after the secondary pressure regulator through the third pressure detector 11, obtains the temperature T3 after the secondary pressure regulator through the third temperature detector 12, and obtains the instantaneous flow F2 before the secondary pressure regulator through the second flow detector 9. In order to ensure that the outlet temperature of the secondary pressure regulator reaches a certain temperature 5℃, the temperature T1" that the gas temperature before the secondary pressure regulator should reach should be:

[0087] Formula 3: T1"=T3-(μj*(P3-P2))

[0088] In the formula: T1" - temperature before the secondary pressure regulator (℃)

[0089] μj - Joule-Thomson coefficient of natural gas (℃ / MPa, which can be found in relevant literature)

[0090] P2 - pressure before the secondary pressure regulator (MPa, absolute pressure)

[0091] P3 - pressure after the second pressure regulator (MPa, absolute pressure)

[0092] T3 - natural gas temperature after the second pressure regulator (℃).

[0093] Through the calculation of formula 3, the temperature value that the second pressure regulator before should reach at least can be calculated when ensuring the temperature of the second pressure regulator outlet reaches 5℃, and then the theoretical second heater function rate P' can be calculated through the temperature difference between the second heater inlet and outlet: formula 4: P' = (F2*ρ*C*(T1"-T2)) / (k*3600)

[0094] In the formula: T1" - calculated temperature before the second pressure regulator (℃)

[0095] F2 - instantaneous flow before the second pressure regulator (Nm 3 / h)

[0096] ρ - standard density of natural gas (the value is 0.75 Kg / Nm 3 )

[0097] C - specific heat capacity of natural gas (the value is 2.156 KJ / (Kg*K))

[0098] T2 - natural gas temperature after the first pressure regulator (℃)

[0099] k - electric heater electric heating conversion and heat exchange coefficient (the value is 0.85-0.95).

[0100] Through the calculation of formula 4, the power of the second heater required to ensure the temperature of the second pressure regulator outlet reaches the set value can be obtained, and then the power of the second heater is adjusted to the appropriate position through the output of the control system.

[0101] The preferred embodiments of the present application are described above, however, the above description is not used for the purpose of limitation. Those skilled in the art can make many changes or modifications to the present application without departing from the spirit and scope of the present application. The changes or modifications should be included in the scope of the appended claims.

Claims

1. A temperature control device based on a gas pressure regulating station, characterized by, It includes a primary pressure regulator (1) and a secondary pressure regulator (2) for adjusting gas pressure, the gas inlet of the primary pressure regulator (1) is connected with a high-pressure inlet pipeline (L1), the high-pressure inlet pipeline (L1) is provided with a first temperature detector (3), a first flow detector (4), a first heater (5), and a first pressure detector (6) in sequence along the gas conveying direction, the gas output pipeline of the primary pressure regulator (1) is branched into a branch pipe (L2) as a gas output pipeline to convey gas to the outside of the pressure regulating station after passing through a second pressure detector (7) and a second temperature detector (8) in sequence, and / or is connected with a downstream pipeline after passing through a second flow detector (9), a second heater (10), a secondary pressure regulator (2), a third pressure detector (11), and a third temperature detector (12) in sequence, the first temperature detector (3), the first flow detector (4), the first heater (5), the first pressure detector (6), the second pressure detector (7), the second temperature detector (8), the second flow detector (9), the second heater (10), the third pressure detector (11), and the third temperature detector (12) are connected with a control system (13); The control system (13) is an automatic control system, the control system (13) acquires temperature, pressure, and flow signals of the first temperature detector (3), the first flow detector (4), the first pressure detector (6), the second pressure detector (7), the second temperature detector (8), the second flow detector (9), the third pressure detector (11), and the third temperature detector (12) to control the heating power of the first heater (5) and the second heater (10), so as to adjust the outbound temperature of the gas in real time; The control system (13) is wirelessly connected or connected through wires with the first temperature detector (3), the first flow detector (4), the first heater (5), the first pressure detector (6), the second pressure detector (7), the second temperature detector (8), the second flow detector (9), the second heater (10), the third pressure detector (11), and the third temperature detector (12), The first heater (5) and the second heater (10) are gas electric heaters.

2. The temperature control device based on a gas pressure regulating station according to claim 1, characterized in that, A first manifold (14) for stabilizing airflow is arranged on the high-pressure inlet pipeline between the first temperature detector (3) and the first flow detector (4).

3. The temperature control device based on a gas pressure regulating station according to claim 1, characterized in that, The gas output pipeline after the second temperature detector is branched into multiple branch pipes through a second manifold (15).

4. The temperature control device based on a gas pressure regulating station according to claim 1, characterized in that, A third manifold (16) is arranged on the branch pipe after the third temperature detector.

5. A gas pressure regulating station outbound temperature adjusting method using the gas pressure regulating station temperature control device according to any one of claims 1-4, the method comprising the following steps: The high-pressure gas flows through the first temperature detector, optionally through the first manifold, and then enters the first flow detector, and then enters the first heater for the first temperature rise. The heated gas passes through the first pressure detector and enters the first pressure regulator for the first pressure reduction. The reduced pressure gas passes through the second pressure detector and the second temperature detector in turn, and then optionally enters the second manifold. The gas output from the second manifold is directly output as the sub-high-pressure gas to the outside of the pressure regulating station. (1) In the gas pressure regulating process, the control system obtains the inlet gas temperature T1 through the first temperature detector, the pressure P1 before the first pressure regulator through the first pressure detector, the temperature T2 after the first pressure regulator through the second temperature detector, the pressure P2 after the first pressure regulator through the second pressure detector, and the instantaneous flow F1 before the first pressure regulator through the first flow detector. In order to make the outlet temperature of the first pressure regulator reach a certain temperature T2, the temperature T1' reached by the gas before the first pressure regulator is: Formula 1: T1'=T2-(μj*(P2-P1)) In the formula: T1' —— the temperature before the first pressure regulator, ℃; μj —— the natural gas Joule-Thomson coefficient, ℃ / MPa; P1 —— the pressure before the first pressure regulator, MPa, absolute pressure; P2 —— the pressure after the first pressure regulator, MPa, absolute pressure; T2 —— the natural gas temperature after the first pressure regulator, ℃; Through the calculation of formula 1, the temperature value reached by the first pressure regulator is calculated when the outlet temperature of the first pressure regulator reaches T2. Then, through the temperature difference between the inlet and outlet of the first heater, the theoretical electric heater power P is calculated: Formula 2: P=(F1*ρ*C*(T1'-T1)) / (k*3600) In the formula: T1' —— the temperature before the first pressure regulator, ℃; F1 —— First-order pressure regulator front transient flow, Nm 3 / h; p - natural gas standard density, with a value of 0.75 Kg / Nm 3 ; C —— the specific heat capacity of natural gas, taking the value of 2.156 KJ / (Kg*K); T1 —— the inlet gas temperature, ℃; k —— the electric heater conversion and heat exchange coefficient, taking the value of 0.85~0.95; Through the calculation of formula 2, the power of the first heater required to make the outlet temperature T2 of the first pressure regulator reach the set value is obtained. Then, the power of the first heater is adjusted to the power through the output of the control system. The other way of the gas output from the second temperature detector or from the second manifold enters the second heater for the second temperature rise through the second flow detector. The heated gas enters the second pressure regulator for the second pressure reduction to obtain the medium-pressure gas. The second pressure-reduced gas passes through the third pressure detector and the third temperature detector in turn, and then optionally enters the third manifold. The medium-pressure gas output from the third manifold is output to the outside of the pressure regulating station. (2) The control system obtains the pressure P3 after the second pressure regulator through the third pressure detector, the temperature T3 after the second pressure regulator through the third temperature detector, and the instantaneous flow F2 before the second pressure regulator through the second flow detector. In order to make the outlet temperature of the second pressure regulator reach a certain temperature T3, the temperature T1" reached by the gas before the second pressure regulator is: Formula 3: T1"=T3-(μj*(P3-P2)) T1" —— temperature before the second pressure regulator, ℃; μj —— natural gas Joule-Thomson coefficient, ℃ / MPa; P2 —— pressure before the second pressure regulator, MPa, absolute pressure; P3 —— pressure after the second pressure regulator, MPa, absolute pressure; T3 —— natural gas temperature after the second pressure regulator, ℃; Through the calculation of formula 3, the temperature value before the second pressure regulator that should be reached at least is calculated to ensure that the outlet temperature of the second pressure regulator reaches T3, and then the theoretical second heater power P' is calculated through the temperature difference between the inlet and outlet of the second heater: Formula 4: P' = (F2 * p * C * (T1" - T2)) / (k * 3600) T1" —— temperature before the second pressure regulator, ℃; F2 - Instantaneous flow before secondary pressure regulator, Nm 3 / h; p - natural gas standard density, with a value of 0.75 Kg / Nm 3 ; C —— specific heat capacity of natural gas, taken as 2.156 KJ / (Kg*K); T2 —— natural gas temperature after the first pressure regulator, ℃; k —— electric heater electric heating conversion and heat exchange coefficient, taken as 0.85-0.95; Through the calculation of formula 4, the power of the second heater required to make the outlet temperature of the second pressure regulator reach the set value T3 is obtained, and then the power of the second heater is adjusted to the power through the output of the control system.

6. The outlet temperature regulation method for a gas pressure regulating station according to claim 5, characterized in that, When the power control fails, the outlet temperature of the pressure regulator is lower than the set value, and then the temperature control override mode is entered, the control system uses the temperature T2 after the first pressure regulator or the temperature T3 after the second pressure regulator for override control, and when the calculation output through formula 2 or formula 4 cannot meet the temperature setting value after pressure regulation, the control mode of the control system is forced to switch to the temperature regulation mode, that is, the output signal of the control system is forced to increase the heating power to increase the temperature T2 or T3 after the pressure regulator.

7. The outlet temperature regulating method of a gas pressure regulating station according to claim 5, wherein The temperature T2 is 2-8℃; and / or, the temperature T3 is 4-8℃.

8. The outlet temperature regulation method for a gas pressure regulating station according to claim 7, characterized in that, The temperature T2 is 4-8℃; and / or, the temperature T3 is 5℃.

9. The method for regulating the outlet temperature of a gas pressure regulating station according to claim 8, characterized in that, The temperature T2 is 5℃.

10. The outlet temperature regulating method of a gas pressure regulating station according to claim 6, wherein The temperature setting value after pressure regulation is 0℃.

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