CN212563353U - Energy-saving primary frequency modulation control device capable of changing low-pressure heating and heat storage - Google Patents
Energy-saving primary frequency modulation control device capable of changing low-pressure heating and heat storage Download PDFInfo
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- CN212563353U CN212563353U CN202020850176.7U CN202020850176U CN212563353U CN 212563353 U CN212563353 U CN 212563353U CN 202020850176 U CN202020850176 U CN 202020850176U CN 212563353 U CN212563353 U CN 212563353U
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Abstract
The utility model relates to an energy-saving primary frequency modulation control device for changing low-pressure heating and heat accumulation, which comprises a frequency modulation system and a regenerative steam extraction system which are connected in sequence, wherein; the system comprises a heat recovery steam extraction system, a heat recovery steam extraction system and a control system, wherein the heat recovery steam extraction system comprises a deoxidizing heater, a frequency modulation controller, a condenser, a condensate pump and a low-pressure heater, and the deoxidizing heater, the condenser and the low-pressure heater are respectively connected with the frequency modulation system through pipelines; in the utility model, after the liquid level information of the low-pressure heater and the deoxidizing heater is converted into a current signal, the current signal is sent into the frequency modulation controller through the signal cable; the frequency modulation controller evaluates and calculates the liquid level to obtain the final condensate flow needing to be changed, then the frequency modulation controller converts the condensate flow into a control signal for controlling the condensate pump, and the condensate pump is driven by a signal cable to finally achieve the purpose of changing the condensate flow, so that the primary frequency modulation performance is greatly improved under the condition of not changing the opening of a steam turbine regulating valve.
Description
Technical Field
The utility model relates to a power grid performance adjustment control technical field especially relates to an energy-saving changes low primary control device who adds heat accumulation.
Background
In the industrial production process (such as thermal power generation), the frequency is one of important indexes for measuring the quality of electric energy, and the guarantee of the system frequency meeting the standard is a basic task for the safe and stable operation of an electric power system. The primary frequency modulation is an important means for keeping the frequency stability of the system, and the output of the generator is increased or decreased according to the frequency static characteristic of the generator speed regulating system so as to play a role in frequency modulation. When the frequency of the power grid deviates from a rated value, the generator set regulation control system automatically controls the active power of the generator set to increase (when the frequency decreases) or decrease (when the frequency increases), so that the change of the frequency of the power grid is restrained. At present, with the active construction and the vigorous development of new energy power generation such as wind energy and solar energy of an extra-high voltage power transmission network, new challenges are brought to power grid frequency adjustment by the direct current blocking hidden danger of the extra-high voltage power transmission network and the fluctuation of the new energy power generation, and a thermal power generating unit needs to participate in primary frequency modulation more deeply.
In the current industrial production processes of thermal power generation and the like, the main mode of responding to primary frequency modulation of a thermal power generating unit depends on a steam turbine regulating valve to perform corresponding actions when the frequency of a power grid changes. At present, along with the requirement of a power grid on deep frequency modulation and the economic requirement of sliding pressure operation of a thermal power generating unit, a turbine regulating valve is in a fully open position for a long time, and because a turbine cannot be in the fully open position in the process of regulating the turbine regulating valve, the specific requirement of primary frequency modulation of the power grid cannot be met in actual production by a conventional action mode of responding to primary frequency modulation through the turbine regulating valve.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that the conventional action mode of responding primary frequency modulation through the steam turbine valve of solving can not satisfy the problem that electric wire netting primary frequency modulation required in actual production.
The utility model discloses a following technical means realizes solving above-mentioned technical problem:
an energy-saving primary frequency modulation control device for changing low-pressure heat accumulation comprises a frequency modulation system and a regenerative steam extraction system which are sequentially connected, wherein the regenerative steam extraction system comprises a primary frequency modulation control device and a secondary frequency modulation control device;
the system comprises a heat recovery steam extraction system, a heat recovery steam extraction system and a control system, wherein the heat recovery steam extraction system comprises a deoxidizing heater, a frequency modulation controller, a condenser, a condensate pump and a low-pressure heater, wherein the deoxidizing heater, the condenser and the low-pressure heater are respectively connected with the frequency modulation system through pipelines;
liquid level transmitters are fixedly arranged on the shell walls of the deoxidizing heater and the low-pressure heater, and the output ends of the liquid level transmitters are in communication connection with the input end of the frequency modulation controller;
the frequency modulation controller is electrically connected with the frequency modulation system, and the output end of the frequency modulation controller is also electrically connected with the input end of the condensate pump;
the condenser is communicated with a condensate pump through a pipeline, the condensate pump is communicated with a low-pressure heater through a pipeline, and the output end of the low-pressure heater is communicated with the input end of the deoxidizing heater through a pipeline.
After the liquid level information of the low-pressure heater and the deoxidizing heater is converted into a 4-20mA current signal, the current signal is sent to a frequency modulation controller through a signal cable; the frequency modulation controller evaluates and calculates the liquid level to obtain the final condensate flow needing to be changed, then the frequency modulation controller converts the condensate flow into a control signal for controlling the condensate pump, and the condensate pump is driven by a signal cable to finally achieve the purpose of changing the condensate flow, so that the primary frequency modulation performance is greatly improved under the condition of not changing the opening of a steam turbine regulating valve.
As a further aspect of the present invention: the frequency modulation system comprises a primary frequency modulation controller, a steam turbine and a generator, wherein one end of the steam turbine is communicated with external boiler equipment through a pipeline, the generator at the other end of the steam turbine is electrically connected, and the steam turbine and the generator are also electrically connected with the primary frequency modulation controller respectively.
As a further aspect of the present invention: and the deoxidizing heater, the condenser and the low-pressure heater are respectively communicated with the steam turbine through pipelines.
As a further aspect of the present invention: and the input end of the frequency modulation controller is respectively electrically connected with the steam turbine and the generator.
As a further aspect of the present invention: still include first condensate water valve, the input and the external boiler equipment of first condensate water valve are linked together through the pipeline, two outputs of first condensate water valve are linked together with two inputs of steam turbine, just first condensate water valve still with primary control ware electric connection.
As a further aspect of the present invention: the water-saving control system is characterized by further comprising a second condensed water upper water valve, one end of the second condensed water upper water valve is communicated with the low-pressure heater, the other end of the second condensed water upper water valve is communicated with the condensed water pump, and the second condensed water upper water valve is further electrically connected with the frequency modulation controller.
As a further aspect of the present invention: and the Siemens controller PLC is 412-2DP in model.
The utility model has the advantages that:
1. in the utility model, after the liquid level information of the low-pressure heater and the deoxidizing heater is converted into 4-20mA current signals by the liquid level transmitter, the current signals are sent into the frequency modulation controller through the signal cable; the frequency modulation controller evaluates and calculates the liquid level to obtain the final condensate water flow needing to be changed, then the frequency modulation controller converts the final condensate water flow needing to be changed into a control signal for controlling the condensate water pump, the condensate water pump is driven by a signal cable, the water flow extracted by the condensate water pump from the condenser is reduced or increased, the water amount reaching the low-pressure heater and the deoxidizing heater is reduced or increased sequentially at the moment, the condensate water flow inside the deoxidizing heater can be reduced or increased along with the condensate water flow, the purpose of changing the condensate water flow is finally achieved, meanwhile, the temperature and the pressure of the low-pressure heater are increased or decreased, the steam extraction amount of the low-pressure heater from the steam turbine is reduced or increased, the opening degree of a steam turbine throttle does not need to be adjusted, and the frequency modulation performance is greatly improved under the condition that the.
2. The utility model discloses ensured that thermal power generating unit can realize the energy-conserving sliding pressure operation that the steam turbine accent door was opened entirely under the prerequisite of guaranteeing that primary frequency modulation performance satisfies the electric wire netting requirement.
Drawings
Fig. 1 is a schematic structural diagram of the energy-saving primary frequency modulation control device for changing low heating capacity.
Fig. 2 is a working principle diagram of the present invention.
In the figure, 1-primary frequency modulation controller, 2-steam turbine, 3-generator, 4-deoxygenation heater, 5-frequency modulation controller, 6-condenser, 7-condensate pump, 8-low pressure heater, 901-first condensate water valve, 902-second condensate water valve.
Detailed Description
To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the embodiments of the present invention are combined to clearly and completely describe the technical solution in the embodiments of the present invention, and obviously, the described embodiments are some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
First, for a better understanding of the present invention, the low-pressure addition commonly used in the art, which is a low-pressure heater, is generally referred to in the industry as simply low-pressure addition.
Example 1
Referring to fig. 1, fig. 1 is a schematic structural diagram of an energy-saving primary frequency modulation control device for changing low-pressure heat accumulation provided by the present invention, which comprises a frequency modulation system and a regenerative steam extraction system connected in sequence, wherein,
the frequency modulation system comprises a primary frequency modulation controller 1, a steam turbine 2 and a generator 3, wherein one end of the steam turbine 2 is communicated with external boiler equipment through a pipeline, the other end of the steam turbine 2 is electrically connected with the generator 3, and the steam turbine 2 and the generator 3 are also electrically connected with the primary frequency modulation controller 1 respectively; the primary frequency modulation controller 1 is a common device in the technical field of thermal power generating units, and the working principle of the primary frequency modulation controller is not described in detail here.
In fig. 1, the regenerative steam extraction system includes a deoxidizing heater 4, a frequency modulation controller 5, a condenser 6, a condensate pump 7, and a low-pressure heater 8, wherein the deoxidizing heater 4, the condenser 6, and the low-pressure heater 8 are respectively communicated with the steam turbine 2 through pipelines.
In fig. 1, the output end of the deoxygenation heater 4 and the output end of the low-pressure heater 8 are both in communication connection with the input end of the frequency modulation controller 5, so that an electric signal containing water level information is sent to the frequency modulation controller 5;
specifically, in this embodiment, further, the housing walls of the oxygen removal heater 4 and the low pressure heater 8 are all welded with liquid level transmitters, the liquid level transmitters can read the water pressures of the oxygen removal heater 4 and the low pressure heater 8, the liquid level information (the water pressure at this time) of the oxygen removal heater 4 and the low pressure heater 8 can be converted into 4-20mA current signals by the liquid level transmitters, and the current signals are sent to the frequency modulation controller 5.
It is emphasized that the model of the level transmitter in this embodiment is chosen according to the actual situation, for example, the model is GLP2881, but is not limited to this model.
In fig. 1, the input end of the fm controller 5 is further electrically connected to the steam turbine 2 and the generator 3 to obtain the rotation speed and the frequency signal of the steam turbine 2 and the power signal of the generator 2.
In fig. 1, the condenser 6 is communicated with the condensate pump 7 through a pipeline, the condensate pump 7 is communicated with the low-pressure heater 8 through a pipeline, and the low-pressure heater 8 is communicated with the deoxidizing heater 4 through a pipeline.
Furthermore, the output end of the frequency modulation controller 5 is electrically connected with the input end of the condensate pump 7 to control the operation of the condensate pump 7.
Further, in fig. 1, the system further includes a first condensed water upper water valve 901 and a second condensed water upper water valve 902, wherein an input end of the first condensed water upper water valve 901 is communicated with external boiler equipment through a pipeline, two output ends of the first condensed water upper water valve 901 are communicated with two input ends of a steam turbine 2, the first condensed water upper water valve 901 is further electrically connected with a primary frequency modulation controller 1, and the primary frequency modulation controller 1 sends a control signal to drive the first condensed water upper water valve 901 to operate, so as to control the first condensed water upper water valve 901 to open and close;
in fig. 1, one end of the second condensed water upper water valve 902 is communicated with the low-pressure heater 8, the other end is communicated with the condensed water pump 7, the second condensed water upper water valve 902 is further electrically connected with the frequency modulation controller 5, and the frequency modulation controller 5 sends out a control signal to drive the second condensed water upper water valve 902 to work, so as to control the opening and closing of the second condensed water upper water valve 902.
Preferably, the electrical connection referred to in this embodiment may be realized by a signal cable connection.
In an exemplary embodiment, the fm controller 5 can evaluate and calculate the liquid level information of the low pressure heater 8 and the deoxidizing heater 4 to obtain the condensate water flow to be changed, and then the fm controller 5 converts the condensate water flow to be changed into control signals (4 to 20mA) for controlling the condensate water pump 7 and the second condensate water upper water valve 902, and the control signals drive the condensate water pump 7 and the second condensate water upper water valve 902 to work through the signal cable, and it is noted that the fm controller 5 estimates the liquid level information to obtain the condensate water flow to be changed as an inherent function, the present invention does not improve the software thereof, and sets different types of fm controllers 5 according to different power grid requirements, and exemplarily, the fm controller 5 may be a westernman controller PLC with a model number of 412 to 2DP, but is not limited to this model.
It should be noted that the present invention does not improve the software program and the internal circuit of the primary frequency modulation controller 1, the frequency modulation controller 5, and the like, and the software program, the internal circuit, and the like are not within the scope of the present invention.
The working principle is as follows:
for more convenient explanation of the working principle of the present invention, reference can be made to fig. 2, and fig. 2 is a working principle diagram of the present invention; when the frequency of the power grid deviates from a rated value and the active power of the generating set is automatically controlled by the generating set adjusting and controlling system to be increased (namely, when the frequency is reduced), the load of the thermal power generating set needs to be increased, the liquid level information of the low-pressure heater 8 and the deoxidizing heater 4 is converted into 4-20mA current signals through the liquid level transmitter and is sent to the frequency modulation controller 5 through the signal cable; the frequency modulation controller 5 evaluates and calculates the liquid level information of the low-pressure heater 8 and the deoxidizing heater 4 to obtain the condensate water flow to be changed, then the frequency modulation controller 5 converts the condensate water flow to be changed into control signals (4-20 mA) for controlling the condensate water pump 7 and the second condensate water upper water valve 902, the control signals drive the condensate water pump 7 and the second condensate water upper water valve 902 to work through signal cables, the water flow extracted from the condenser 6 is reduced, at the moment, the water amount sequentially reaching the low-pressure heater 8 and the deoxidizing heater 4 is reduced, the condensate water flow in the deoxidizing heater 4 is reduced, the purpose of changing the condensate water flow is finally achieved, meanwhile, the temperature and the pressure of the low-pressure heater 8 are increased, the steam extraction amount of the low-pressure heater 8 from the steam turbine 2 is reduced, and the opening degree of a steam turbine throttle is not required to be adjusted, the primary frequency modulation performance is greatly improved under the condition of not changing the opening of a steam turbine valve; the thermal power generating unit can realize the energy-saving sliding pressure operation of the full opening of the turbine regulating valve on the premise of ensuring that the primary frequency modulation performance meets the requirement of a power grid;
when the frequency of the power grid deviates from a rated value and the active power of the generating set is automatically reduced (when the frequency is increased) by the generating set adjusting and controlling system, the load of the thermal power generating set needs to be reduced at the moment, the liquid level information of the low-pressure heater 8 and the deoxidizing heater 4 is converted into 4-20mA current signals through the liquid level transmitter, and the current signals are sent to the frequency modulation controller 5 through the signal cable; the frequency modulation controller 5 evaluates and calculates the liquid level information of the low-pressure heater 8 and the deoxidizing heater 4 to obtain the condensate water flow to be changed, then the frequency modulation controller 5 converts the condensate water flow to be changed into control signals (4-20 mA) for controlling the condensate pump 7 and the second condensate water upper water valve 902, the control signals drive the condensate pump 7 and the second condensate water upper water valve 902 to work through signal cables, the water flow extracted from the condenser 6 is increased, at the moment, the water amount sequentially reaching the low-pressure heater 8 and the deoxidizing heater 4 is also increased, the condensate water flow in the deoxidizing heater 4 is also increased, the purpose of changing the condensate water flow is finally achieved, meanwhile, the temperature and the pressure of the low-pressure heater 8 are reduced, the steam extraction amount of the low-pressure heater 8 from the steam turbine 2 is increased, and the opening degree of the steam turbine is not required to be adjusted, the primary frequency modulation performance is greatly improved under the condition of not changing the opening of a steam turbine valve; the thermal power generating unit can realize the energy-saving sliding pressure operation of the full opening of the turbine regulating valve on the premise of ensuring that the primary frequency modulation performance meets the requirement of a power grid.
The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.
Claims (7)
1. An energy-saving primary frequency modulation control device for changing low-pressure heat accumulation is characterized by comprising a frequency modulation system and a regenerative steam extraction system which are sequentially connected, wherein the regenerative steam extraction system comprises a primary frequency modulation control device and a secondary frequency modulation control device;
the heat recovery steam extraction system comprises a deoxidizing heater (4), a frequency modulation controller (5), a condenser (6), a condensate pump (7) and a low-pressure heater (8), wherein the deoxidizing heater (4), the condenser (6) and the low-pressure heater (8) are respectively connected with the frequency modulation system through pipelines;
liquid level transmitters are fixedly arranged on the shell walls of the deoxidizing heater (4) and the low-pressure heater (8), and the output ends of the liquid level transmitters are in communication connection with the input end of the frequency modulation controller (5);
the frequency modulation controller (5) is electrically connected with the frequency modulation system, and the output end of the frequency modulation controller (5) is also electrically connected with the input end of the condensate pump (7);
the condenser (6) is communicated with a condensate pump (7) through a pipeline, the condensate pump (7) is communicated with a low-pressure heater (8) through a pipeline, and the output end of the low-pressure heater (8) is communicated with the input end of the deoxidizing heater (4) through a pipeline.
2. The energy-saving primary frequency modulation control device for changing low heating and storage capacity according to claim 1, wherein the frequency modulation system comprises a primary frequency modulation controller (1), a steam turbine (2) and a generator (3), one end of the steam turbine (2) is communicated with external boiler equipment through a pipeline, the other end of the steam turbine (2) is electrically connected with the generator (3), and the steam turbine (2) and the generator (3) are also electrically connected with the primary frequency modulation controller (1) respectively.
3. An energy-saving primary frequency modulation control device for changing low-heating capacity according to claim 2, characterized in that the oxygen-removing heater (4), the condenser (6) and the low-pressure heater (8) are respectively communicated with the steam turbine (2) through pipelines.
4. An energy-saving primary frequency modulation control device for changing low-heating storage capacity according to claim 2, wherein the input end of the frequency modulation controller (5) is electrically connected with the steam turbine (2) and the generator (3) respectively.
5. The energy-saving primary frequency modulation control device for changing low heating and storage capacity according to claim 2, further comprising a first condensed water upper water valve (901), wherein an input end of the first condensed water upper water valve (901) is communicated with external boiler equipment through a pipeline, two output ends of the first condensed water upper water valve (901) are communicated with two input ends of the steam turbine (2), and the first condensed water upper water valve (901) is further electrically connected with the primary frequency modulation controller (1).
6. The energy-saving primary frequency modulation control device for changing low-heat-accumulation according to claim 2, further comprising a second condensate water upper water valve (902), wherein one end of the second condensate water upper water valve (902) is communicated with the low-pressure heater (8), the other end of the second condensate water upper water valve is communicated with the condensate pump (7), and the second condensate water upper water valve (902) is further electrically connected with the frequency modulation controller (5).
7. An energy-saving primary frequency modulation control device for changing low-heat-adding storage according to claim 1, characterized in that the frequency modulation controller (5) is a Siemens controller PLC with the model number of 412-2 DP.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113294220A (en) * | 2021-06-04 | 2021-08-24 | 神华神东电力有限责任公司 | Load adjusting method and device for generator set |
| CN115324675A (en) * | 2022-07-25 | 2022-11-11 | 广西电网有限责任公司电力科学研究院 | Control method for adjusting power grid frequency of thermal power generating unit based on variable-frequency condensate pump |
| CN115324674A (en) * | 2022-07-25 | 2022-11-11 | 广西电网有限责任公司电力科学研究院 | System for frequency conversion condensate pump of thermal power generating unit participates in power grid frequency adjustment |
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2020
- 2020-05-20 CN CN202020850176.7U patent/CN212563353U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113294220A (en) * | 2021-06-04 | 2021-08-24 | 神华神东电力有限责任公司 | Load adjusting method and device for generator set |
| CN115324675A (en) * | 2022-07-25 | 2022-11-11 | 广西电网有限责任公司电力科学研究院 | Control method for adjusting power grid frequency of thermal power generating unit based on variable-frequency condensate pump |
| CN115324674A (en) * | 2022-07-25 | 2022-11-11 | 广西电网有限责任公司电力科学研究院 | System for frequency conversion condensate pump of thermal power generating unit participates in power grid frequency adjustment |
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