阅读说明：本技术 一种提高再热式汽轮机供汽能力及机组效率的系统和方法 (System and method for improving steam supply capacity and unit efficiency of reheat steam turbine ) 是由 裴东升 何欣欣 杜文斌 陈会勇 王伟锋 赵杰 于 2020-05-26 设计创作，主要内容包括：本发明公开了一种提高再热式汽轮机供汽能力及机组效率的系统和方法,该系统包括给水旁路换热系统、供热系统和反馈控制系统。本发明通过同时调节中压缸供热抽汽调节阀和冷再热蒸汽至压力匹配器蒸汽调节阀的开度,使汽水换热器出口蒸汽压力和流量同时满足用户需求。根据用户的温度需求,结合根据汽水换热器的换热特性,控制给水泵出口至汽水换热器进水管道对应的给水流量。最后根据温度测量值选择汽水换热器回水管道中回水位置并开启对应的电动阀门。提供一种普适性和供热蒸汽温度参数调节能力较强,且无需设置喷水减温装置,可用于对在役机组进行供热改造,提升其工业供汽能力和机组效率的系统。(The invention discloses a system and a method for improving steam supply capacity and unit efficiency of a reheating steam turbine. The invention simultaneously adjusts the opening of the intermediate pressure cylinder heat supply extraction steam adjusting valve and the opening of the cold reheat steam to the steam adjusting valve of the pressure matcher, so that the steam pressure and the flow at the outlet of the steam-water heat exchanger can simultaneously meet the requirements of users. And controlling the water supply flow from the outlet of the water supply pump to the water inlet pipeline of the steam-water heat exchanger according to the temperature requirement of a user and the heat exchange characteristic of the steam-water heat exchanger. And finally, selecting a water return position in a water return pipeline of the steam-water heat exchanger according to the temperature measurement value and opening a corresponding electric valve. The system has strong universality and high regulation capacity of temperature parameters of heating steam, does not need to be provided with a water spraying temperature reduction device, can be used for carrying out heat supply transformation on an in-service unit, and improves the industrial steam supply capacity and the unit efficiency.)

1. A system for improving the steam supply capacity and the unit efficiency of a reheat steam turbine is characterized by comprising a steam-water system of the steam turbine unit, a water supply bypass heat exchange system, a heat supply system and a feedback control system; wherein the content of the first and second substances,

the steam-water system of the steam turbine set comprises a boiler (1), an outlet of a superheated steam pipeline of the boiler (1) is communicated with a steam inlet of a high-pressure cylinder (2), a steam outlet of the high-pressure cylinder (2) is communicated with an inlet of a reheated steam pipeline of the boiler (1), an outlet of the reheated steam pipeline of the boiler (1) is communicated with a steam inlet of an intermediate-pressure cylinder (3), a first-stage steam extraction port and a second-stage steam extraction port of the high-pressure cylinder (2) are respectively communicated with steam inlets of a first-stage high pressure booster (J1) and a second-stage high pressure booster (J2), a first-stage steam extraction port and a second-stage steam extraction port of the intermediate-pressure cylinder (3) are respectively communicated with steam inlets of a third-stage high pressure booster (J3) and a deaerator (5), the water inlets and the water outlets of the third-stage high-pressure boiler (J3), the second-stage high-pressure boiler (J2) and the first-stage high-pressure boiler (J1) are communicated in sequence, and the water outlet of the first-stage high-pressure boiler (J1) is communicated with the inlet of a water supply pipeline of the boiler (1);

the water supply bypass heat exchange system comprises a water supply pump outlet to a steam-water heat exchanger water inlet pipeline (L7), a water supply pump outlet to steam-water heat exchanger water inlet pipeline (L7) is led out from a water supply pump to a branch of a third-level high pressure water supply pipeline (L4) and is communicated with a water inlet of a steam-water heat exchanger (J4), a water supply bypass to steam-water heat exchanger water inlet electric valve (V4) is installed on the water supply pump outlet to the steam-water heat exchanger water inlet pipeline (L7), a water outlet of the steam-water heat exchanger (J4) is communicated with a steam-water heat exchanger water return pipeline (L8), the steam-water heat exchanger water return pipeline (L8) is communicated with a first-level high pressure water supply outlet electric valve (V1) and a first-level high pressure boiler water supply pipeline (L1) through a steam-water heat exchanger water outlet to a second-level high pressure water supply outlet electric valve (V2) and a second-level high pressure water supply pipeline, a water return pipeline (L8) of the steam-water heat exchanger is communicated with a third-level high-pressure water feeding pipeline (L3) through an electric valve (V3) of a third-level high-pressure water feeding outlet of the steam-water heat exchanger;

the heat supply system comprises a pressure matcher (6), wherein the inlet of the pressure matcher (6) is respectively communicated with a heat supply steam extraction pipeline (L6) of an intermediate pressure cylinder and a steam pipeline (L5) for conveying cold reheat steam to the pressure matcher, an intermediate pressure cylinder heat supply steam extraction regulating valve (V6) is installed on the heat supply steam extraction pipeline (L6) of the intermediate pressure cylinder, the steam pipeline (L5) for conveying cold reheat steam to the pressure matcher is provided with a steam regulating valve (V5) for conveying cold reheat steam to the pressure matcher, the outlet of the pressure matcher (6) is communicated with the steam inlet of a steam-water heat exchanger (J4), and the steam outlet of the steam-water heat exchanger (J4) is communicated with a steam pipeline (L9) for conveying steam from the;

a first temperature measuring point (T1) is arranged on a pipeline from the steam-water heat exchanger to user steam (L9), a second temperature measuring point (T2) is arranged on a pipeline from a water feed pump to a third-level high pressure feed water (L4), and a third temperature measuring point (T3) is arranged on a water return pipeline (L8) of the steam-water heat exchanger;

the feedback control system comprises a feedback controller (C1), wherein an inlet of the feedback controller (C1) is communicated with a first temperature measuring point (T1), a second temperature measuring point (T2) is communicated with a third temperature measuring point (T3), an outlet of the feedback controller (C1) is communicated with a steam-water heat exchanger water outlet to first-stage high-pressure water outlet electric valve (V1), a steam-water heat exchanger water outlet to second-stage high-pressure water outlet electric valve (V2), a steam-water heat exchanger water outlet to third-stage high-pressure water outlet electric valve (V3) and a water supply bypass to steam-water heat exchanger water inlet electric valve (V4).

2. The system according to claim 1, wherein the opening is made in the intermediate pressure cylinder block according to a pressure requirement of a user.

3. A method for improving the steam supply capacity and the unit efficiency of a reheat steam turbine, which is based on the system for improving the steam supply capacity and the unit efficiency of a reheat steam turbine according to claim 1 or 2, comprising the following steps:

the method comprises the following steps: when the load of the unit is high and the heat supply steam extraction of the intermediate pressure cylinder can meet the pressure requirement of a user, closing a steam regulating valve (V5) of the pressure matcher for cold reheat steam, and regulating the opening degree of the heat supply steam extraction regulating valve (V6) of the intermediate pressure cylinder to enable the flow of the outlet steam of the steam-water heat exchanger (6) to meet the requirement of the user; when the load of the unit is low and the heat supply steam extraction of the intermediate pressure cylinder cannot meet the pressure requirement of a user, the opening degrees of a heat supply steam extraction regulating valve (V6) of the intermediate pressure cylinder and the steam regulating valve (V5) of a cold reheat steam to a pressure matcher are simultaneously adjusted, so that the outlet steam pressure and the flow of the steam-water heat exchanger (6) can simultaneously meet the requirement of the user;

step two: setting a target value of the first temperature measuring point (T1) in a feedback controller (C1) according to the temperature requirement of a user, and simultaneously transmitting the measured values of the first temperature measuring point (T1) and the second temperature measuring point (T2) to the feedback controller (C1);

step three: processing in a feedback controller (C1) according to the heat exchange characteristics of the steam-water heat exchanger (J4) and the measured values of a first temperature measuring point (T1) and a second temperature measuring point (T2), and controlling the feed water flow corresponding to the feed water pump outlet to a steam-water heat exchanger water inlet pipeline (L7) by controlling the opening degree of a feed water bypass to a steam-water heat exchanger water inlet electric valve (V4);

step four: and transmitting the measured value of the third temperature measuring point (T3) to a feedback controller (C1), selecting a water return position in a water return pipeline (L8) of the steam-water heat exchanger as a first-level high water feeding pipeline (L1), a second-level high water feeding pipeline (L2) or a third-level high water feeding pipeline (L3), opening a corresponding control valve to enable water to flow out of the steam-water heat exchanger to a first-level high water outlet electric valve (V1) or to enable water to flow out of the steam-water heat exchanger to a second-level high water outlet electric valve (V2) or to flow out of the steam-water heat exchanger to a third-level high water outlet electric valve (V3) after confirming the position, and closing the other two control valves.

Technical Field

The invention belongs to the technical field of steam extraction and heat supply of a steam turbine, and particularly relates to a system and a method for improving the steam supply capacity and the unit efficiency of a reheating steam turbine.

Background

In recent years, in order to realize energy conservation and emission reduction and fully utilize the superiority of cogeneration, more and more reheating condensing units are transformed into heating units. In some current heating systems, when the steam temperature parameter of user's demand is lower, the temperature of heat supply steam and the required heat supply temperature of user differ greatly, need use the water spray to reduce the temperature to high temperature heat supply steam, lead to the energy of high temperature heat supply steam not to obtain make full use of.

At present, some devices are also used for increasing the temperature of feed water by using the superheat degree of heating steam, reducing the heat absorption capacity of unit feed water in a boiler and improving the comprehensive energy utilization efficiency of a power plant. If the granted date is 2016, 8, 31 and chinese patent with the granted publication number of CN205535722U, an energy cascade utilization device for an extraction steam heating system is disclosed, which needs to directly replace part of regenerative heaters according to the principle that the boiler water supply return water and the heating extraction steam temperature are matched, if a heat supply reconstruction is performed on a unit in service, the scheme may cause parameter mismatching to cause the non-optimal or even reduced thermal efficiency of the whole unit, and also cause unqualified denitration indexes due to low water supply temperature during low load operation, and the universality of the system is limited. Therefore, the device is more suitable for the design of a newly-built heat supply unit (the system influencing the heat supply unit needs to be greatly improved and designed), and is not suitable for the heat supply reconstruction of an in-service unit. For example, chinese patent with publication number CN205957140U, whose granted date is 2017, 2, 15 and granted publication number is CN205957140U, discloses a heating system with high heat utilization rate. The heating system utilizes partial superheat degree of high-temperature steam in a mode of additionally arranging a steam cooler to heat final feed water of a boiler. The steam cooler of the system only heats final feed water, the system is relatively simplified, but the application range and the adjusting capacity of the temperature of the heating steam are limited, so a water spraying temperature reducing device still needs to be arranged.

In summary, for the heat supply transformation of the in-service unit, a system which has strong universality and heat supply steam temperature parameter adjusting capability, does not need to be provided with a water spray temperature reducing device and can be used for improving the industrial steam supply capability and the unit efficiency does not exist at present.

Disclosure of Invention

The invention aims to provide a system and a method which have strong applicability and parameter adjusting capability and can be used for carrying out heat supply transformation on an in-service reheating type steam turbine unit so as to improve the industrial steam supply capability and the unit efficiency of the in-service reheating type steam turbine unit.

The invention is realized by adopting the following technical scheme:

a system for improving steam supply capacity and unit efficiency of a reheat steam turbine comprises a steam-water system of the steam turbine unit, a water supply bypass heat exchange system, a heat supply system and a feedback control system; the steam-water system of the steam turbine set comprises a boiler, wherein an outlet of a superheated steam pipeline of the boiler is communicated with a steam inlet of a high-pressure cylinder, a steam outlet of a high-pressure cylinder is communicated with an inlet of a reheated steam pipeline of the boiler, an outlet of the reheated steam pipeline of the boiler is communicated with a steam inlet of an intermediate-pressure cylinder, a first-section steam extraction port and a second-section steam extraction port of the high-pressure cylinder are respectively communicated with steam inlets of a first-stage high heater and a second-stage high heater, a first-section steam extraction port and a second-section steam extraction port of the intermediate-pressure cylinder are respectively communicated with steam inlets of a third-stage high heater and a deaerator, a water feed pump, a third-stage high heater, a second-stage high heater and a water inlet and a water;

the water supply bypass heat exchange system comprises a water supply pump outlet and a water inlet pipeline of the steam-water heat exchanger, the water supply pump outlet and the water inlet pipeline of the steam-water heat exchanger are led out from a branch of the water supply pump to the third-stage high-pressure water supply pipeline, the water supply bypass is arranged on a water inlet pipeline from an outlet of the water supply pump to the steam-water heat exchanger, a water inlet electric valve from the water supply bypass to the steam-water heat exchanger is arranged on the water inlet pipeline from the outlet of the water supply pump to the steam-water heat exchanger, a water outlet of the steam-water heat exchanger is communicated with a water return pipeline of the steam-water heat exchanger, the water return pipeline of the steam-water heat exchanger is communicated with a water supply pipeline of a first-level high pressure boiler through an electric valve for water outlet of the steam-water heat exchanger to a second-level high pressure water supply pipeline and a water supply pipeline for water outlet of a second-level high pressure boiler to a first-level high pressure water supply pipeline through an electric valve for water outlet of the;

the heat supply system comprises a pressure matcher, wherein inlets of the pressure matcher are respectively communicated with a heat supply steam extraction pipeline of an intermediate pressure cylinder and a steam pipeline of a cold reheat steam to pressure matcher;

a first temperature measuring point is arranged on a pipeline from the steam-water heat exchanger to the user steam, a second temperature measuring point is arranged on a pipeline from the water feed pump to the third-level high-pressure water supply pipeline, and a third temperature measuring point is arranged on a water return pipeline of the steam-water heat exchanger;

the feedback control system comprises a feedback controller, wherein an inlet of the feedback controller is communicated with a first temperature measuring point, a second temperature measuring point and a third temperature measuring point, an outlet of the feedback controller is communicated with an electric valve for water outlet of the steam-water heat exchanger to a first-stage high pressure water adding outlet, an electric valve for water outlet of the steam-water heat exchanger to a second-stage high pressure water adding outlet, an electric valve for water outlet of the steam-water heat exchanger to a third-stage high pressure water adding outlet and an electric valve for water inlet of the steam-water heat exchanger from a water supply.

A further development of the invention consists in that the intermediate cylinder body is perforated according to the pressure requirements of the user.

A method for improving the steam supply capacity and the unit efficiency of a reheat steam turbine is based on the system for improving the steam supply capacity and the unit efficiency of the reheat steam turbine, and comprises the following operation steps:

the method comprises the following steps: when the load of the unit is high and the heat supply steam extraction of the intermediate pressure cylinder can meet the pressure requirement of a user, closing the cold reheat steam to the steam regulating valve of the pressure matcher, and regulating the opening of the heat supply steam extraction regulating valve of the intermediate pressure cylinder to enable the outlet steam flow of the steam-water heat exchanger to meet the requirement of the user; when the load of the unit is low and the heat supply steam extraction of the intermediate pressure cylinder cannot meet the pressure requirement of a user, the opening degrees of the heat supply steam extraction regulating valve of the intermediate pressure cylinder and the steam regulating valve of the cold reheat steam to the pressure matcher are simultaneously adjusted, so that the outlet steam pressure and the flow of the steam-water heat exchanger can simultaneously meet the requirement of the user;

step two: setting a target value of a first temperature measuring point in a feedback controller according to the temperature requirement of a user, and simultaneously transmitting the measured values of the first temperature measuring point and a second temperature measuring point to the feedback controller;

step three: processing in a feedback controller according to the heat exchange characteristics of the steam-water heat exchanger and the measured values of the first temperature measuring point and the second temperature measuring point, and controlling the water supply flow corresponding to the water inlet pipeline from the outlet of the water supply pump to the steam-water heat exchanger by controlling the opening of the water supply bypass to the water inlet electric valve of the steam-water heat exchanger;

step four: and transmitting the measured value of the third temperature measuring point to a feedback controller, selecting the water return position in the water return pipeline of the steam-water heat exchanger as a first-level height to be added to a boiler water supply pipeline or a second-level height to be added to the first-level height water supply pipeline or a third-level height to be added to the second-level height water supply pipeline according to the temperature measured value, opening the corresponding control valve to enable the steam-water heat exchanger to discharge water to the first-level height water supply outlet electric valve or the steam-water heat exchanger to discharge water to the second-level height water supply outlet electric valve or the steam-water heat exchanger to discharge water to the third-level height water supply outlet.

The invention has at least the following beneficial technical effects:

the invention provides a system and a method for improving the steam supply capacity and the unit efficiency of a reheating steam turbine. And then setting a target value of a first temperature measuring point in a feedback controller according to the temperature requirement of a user, simultaneously transmitting the measured values of the first temperature measuring point and a second temperature measuring point to the feedback controller, and controlling the water supply flow from the outlet of the water supply pump to the water inlet pipeline of the steam-water heat exchanger according to the heat exchange characteristic of the steam-water heat exchanger. And finally, transmitting the measured value of the third temperature measuring point to a feedback controller, selecting a water return position in a water return pipeline of the steam-water heat exchanger according to the measured value of the temperature, and opening a corresponding electric valve. The system has strong universality and high regulation capacity of temperature parameters of heating steam, does not need to be provided with a water spraying temperature reduction device, can be used for carrying out heat supply transformation on an in-service unit, and improves the industrial steam supply capacity and the unit efficiency.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Description of reference numerals:

1. boiler, 2, high pressure cylinder, 3, intermediate pressure cylinder, 4, feed water pump, 5, deaerator, 6, pressure adapter, J1, first level high pressure heater, J2, second level high pressure heater, J3, third level high pressure heater, J4, steam-water heat exchanger, L1, first level high pressure heater to boiler feed water pipe, L2, second level high pressure heater to first level high pressure heater feed water pipe, L3, third level high pressure heater to second level high pressure heater feed water pipe, L4, feed water pump to third level high pressure heater feed water pipe, L5, cold reheat steam to pressure adapter steam pipe, L6, intermediate pressure cylinder heat supply steam extraction pipe, L7, feed water pump outlet to steam-water heat exchanger inlet pipe, L8, steam-water heat exchanger water outlet to first level high pressure heater outlet return water pipe, L9, heat exchanger to user steam pipe, V1, heat exchanger water outlet to first level high pressure heater outlet, V2, steam-water outlet to second level high pressure heater outlet water outlet electric valve, v3, an electric valve for water outlet of the steam-water heat exchanger to a third-level high pressure water outlet, V4, an electric valve for water inlet of the steam-water heat exchanger, V5, a steam regulating valve for cold and reheated steam to a pressure matcher, V6, a heat supply steam extraction regulating valve of an intermediate pressure cylinder, T1, a first temperature measuring point, T2, a second temperature measuring point, T3, a third temperature measuring point, C1 and a feedback controller.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

Referring to fig. 1, the system for improving the steam supply capacity and the unit efficiency of the reheat steam turbine provided by the invention comprises a steam-water system of the steam turbine unit, a water supply bypass heat exchange system, a heat supply system and a feedback control system.

The steam-water system of the steam turbine set comprises a boiler 1, wherein an outlet of a superheated steam pipeline of the boiler 1 is communicated with a steam inlet of a high-pressure cylinder 2, a steam outlet of the high-pressure cylinder 2 is communicated with an inlet of a reheated steam pipeline of the boiler 1, an outlet of the reheated steam pipeline of the boiler 1 is communicated with a steam inlet of an intermediate pressure cylinder 3, a first-stage steam extraction port and a second-stage steam extraction port of the high-pressure cylinder 2 are respectively communicated with steam inlets of a first-stage high-pressure J1 and a second-stage high-pressure J2, a first-stage steam extraction port and a second-stage steam extraction port of the intermediate pressure cylinder 3 are respectively communicated with steam inlets of a third-stage high-pressure J3 and a deaerator 5, water inlets and water outlets of the deaerator 5, a water-feeding pump 4, a third-stage high-pressure J3, a second-stage high-pressure J2 and a first-.

The water supply bypass heat exchange system comprises a water supply pump outlet and a steam-water heat exchanger water inlet pipeline L7, the water supply pump outlet and the steam-water heat exchanger water inlet pipeline L7 are led out from a branch from a water supply pump to a third-level high pressure water supply pipeline L4 and are communicated with a water inlet of a steam-water heat exchanger J4, a water supply bypass and steam-water heat exchanger water inlet electric valve V4 is installed on the water supply pump outlet and the steam-water heat exchanger water inlet pipeline L7, a water outlet of the steam-water heat exchanger J4 is communicated with a steam-water heat exchanger water return pipeline L8, the steam-water heat exchanger water return pipeline L8 is communicated with a first-level high pressure water supply pipeline L1 through a steam-water heat exchanger water outlet and first-level high pressure boiler water supply pipeline V1, the steam-water heat exchanger water return pipeline L8 is communicated with a second-level high pressure water supply pipeline L2 through a steam-water heat exchanger water outlet and a second-level high pressure water supply pipeline L8236, the steam-water The water supply pipe L3 is communicated.

The heating system comprises a pressure matcher 6, wherein the inlet of the pressure matcher 6 is respectively communicated with a medium-pressure cylinder heat supply steam extraction pipeline L6 and a cold reheat steam to pressure matcher steam pipeline L5, a medium-pressure cylinder heat supply steam extraction regulating valve V6 is installed on the medium-pressure cylinder heat supply steam extraction pipeline L6, cold reheat steam to pressure matcher steam pipeline L5 is provided with a cold reheat steam to pressure matcher steam regulating valve V5, the outlet of the pressure matcher 6 is communicated with a steam inlet of a steam-water heat exchanger J4, and a steam outlet of the steam-water heat exchanger J4 is communicated with a steam-water heat exchanger to user steam pipeline L9.

The feedback control system comprises a feedback controller C1, wherein an inlet of a feedback controller C1 is communicated with a first temperature measuring point T1, a second temperature measuring point T2 is communicated with a third temperature measuring point T3, an outlet of the feedback controller C1 is communicated with a steam-water heat exchanger water outlet to first-stage high-pressure water adding outlet electric valve V1, a steam-water heat exchanger water outlet to second-stage high-pressure water adding outlet electric valve V2, a steam-water heat exchanger water outlet to third-stage high-pressure water adding outlet electric valve V3 and a water supply bypass to steam-water heat exchanger water inlet electric valve V4.

In addition, a first temperature measuring point T1 is installed on a steam-water heat exchanger to user steam pipeline L9, a second temperature measuring point T2 is installed on a water supply pump to third-stage high-pressure water supply pipeline L4, and a third temperature measuring point T3 is installed on a steam-water heat exchanger water return pipeline L8.

And (3) opening holes on the cylinder body of the intermediate pressure cylinder according to the pressure requirement of a user, leading out a heat supply steam extraction pipeline L6 of the intermediate pressure cylinder, and calculating the size of the pipeline according to the flow requirement of the user.

The invention provides a method for improving steam supply capacity and unit efficiency of a reheat steam turbine, which comprises the following operation steps:

the method comprises the following steps: when the load of the unit is high and the heat supply steam extraction of the intermediate pressure cylinder can meet the pressure requirement of a user, closing the cold reheat steam to the steam regulating valve V5 of the pressure matcher, and regulating the opening degree of the heat supply steam extraction regulating valve V6 of the intermediate pressure cylinder to enable the outlet steam flow of the steam-water heat exchanger 6 to meet the requirement of the user; when the load of the unit is low and the heat supply steam extraction of the intermediate pressure cylinder cannot meet the pressure requirement of a user, the opening degree of the heat supply steam extraction regulating valve V6 and the opening degree of the cold reheat steam of the intermediate pressure cylinder to the steam regulating valve V5 of the pressure matcher are adjusted simultaneously, so that the outlet steam pressure and the flow of the steam-water heat exchanger 6 can meet the requirement of the user simultaneously.

Step two: the target value for the first temperature measurement point T1 is set in the feedback controller C1 according to the temperature demand of the user, while the measured values of the first temperature measurement point T1 and the second temperature measurement point T2 are transmitted to the feedback controller C1.

Step three: according to the heat exchange characteristics of the steam-water heat exchanger J4 and the measured values of a first temperature measuring point T1 and a second temperature measuring point T2, the measured values are processed in a feedback controller C1, and the feed water flow from the outlet of the feed water pump to the inlet pipeline L7 of the steam-water heat exchanger is controlled by controlling the opening degree of the feed water bypass to the inlet electric valve V4 of the steam-water heat exchanger.

Step four: and transmitting the measured value of the third temperature measuring point T3 to a feedback controller C1, selecting the water return position in a water return pipeline L8 of the steam-water heat exchanger as a first-stage height to be added to a boiler water supply pipeline L1 or a second-stage height to be added to a first-stage height water supply pipeline L2 or a third-stage height to be added to a second-stage height water supply pipeline L3 according to the temperature measured value, opening the corresponding control valve to enable water to flow out of the steam-water heat exchanger to a first-stage height water adding outlet electric valve V1 or to enable water to flow out of the steam-water heat exchanger to a second-stage height water adding outlet electric valve V2 or to enable water to flow out of the steam-water heat exchanger to a.

In the system for improving the steam supply capacity and the unit efficiency of the reheating steam turbine, provided by the invention, the flow of bypass feed water can be comprehensively adjusted, and the position of return water in a return water pipeline of a steam-water heat exchanger is set, so that the universality and the regulation capacity of the temperature parameter of heat supply steam are stronger, a water spray temperature reduction device is not required to be arranged, the system can be used for carrying out heat supply transformation on an in-service unit, and the industrial steam supply capacity and the unit efficiency of the in-service unit are improved.