In-plant electric power system of gas turbine power plant

Abstract

The utility model belongs to the technical field of gas turbine power plants, and particularly relates to an in-plant electric power system of a gas turbine power plant, which comprises a gas turbine generator, a high-voltage plant transformer, a plant high-voltage loop, a connecting bus, an energy storage bus section and an energy storage unit. The gas turbine generator is connected with the high-voltage side of the high-voltage plant transformer, the low-voltage side of the high-voltage plant transformer is connected with the plant high-voltage loop, the connecting bus is connected between the plant high-voltage loop and the energy storage bus section, and the energy storage unit is connected with the energy storage bus section; the energy storage unit is used for storing surplus electric energy in the energy storage bus section, the energy storage unit and the station service high-voltage loop are used for supplying power to a station service electric load and a black-start load of the gas turbine power plant, and the energy storage unit is further used for auxiliary frequency modulation of the gas turbine power plant; the in-plant electric power system of the gas turbine power plant does not need to be externally connected with a standby electric power circuit, topological optimization of an AGC auxiliary frequency modulation system, an auxiliary power system and a black start system is achieved, the construction cost is reduced, and the energy efficiency level is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas turbine power plants, and in particular relates to an in-plant power system of a gas turbine power plant. Background Art

[0002] A gas turbine power plant is a circulation system that utilizes a gas turbine, a generator, a waste heat boiler, and a steam turbine. It recovers the high-temperature exhaust gas discharged by the gas turbine through a waste heat boiler and converts it into steam, and then injects the steam into a steam turbine to generate electricity.

[0003] The existing in-plant power systems of gas turbine power plants usually include AGC auxiliary frequency regulation systems, plant power systems and black start systems. Among them, the AGC auxiliary frequency regulation system is an important means to maintain the safe and stable operation of the power system and ensure the frequency quality requirements. The increasing scale of the power grid and the continuous development of new energy power generation have put forward higher quality, higher efficiency and lower price requirements for AGC frequency regulation services. Electrochemical energy storage is the first choice for AGC energy storage and frequency regulation projects in the power industry because its various technical indicators meet the requirements of power plant construction and the AGC frequency regulation needs of the power grid. Existing gas turbine power plants usually directly connect the gas turbine units to the plant power system as the main power supply of the plant power system. In order to achieve the black start of the gas turbine units in the shortest time when the gas turbine units are shut down and restore the power supply of the plant power system, the existing gas turbine power plants usually have external backup power lines as the backup power supply of the plant power system of the gas turbine power plant, and also serve as the black start system of the gas turbine power plant.

[0004] However, the existing in-plant power system of the gas turbine power plant lacks topological optimization of the AGC auxiliary frequency regulation system, the plant power system and the black start system. The setting method of the external backup power line also has the problem of additionally increasing the construction cost of the gas turbine power plant and reducing the energy efficiency level of the gas turbine power plant. Utility Model Content

[0005] In order to solve the defects of the above-mentioned prior art, the utility model provides an in-plant power system of a gas turbine power plant to solve the problem that the existing in-plant power system of the gas turbine power plant lacks topological optimization of the AGC auxiliary frequency modulation system, the plant power system and the black start system, and the setting method of the external standby power line also has the technical problem of additionally increasing the construction cost of the gas turbine power plant and reducing the energy efficiency level of the gas turbine power plant.

[0006] In order to achieve the above object, the technical solution of the utility model is as follows:

[0007] An in-plant power system of a gas turbine power plant comprises a gas turbine generator, a high-voltage plant transformer, a plant high-voltage circuit, a connecting bus, an energy storage bus section and an energy storage unit;

[0008] The gas turbine generator is connected to the high voltage side of the high voltage plant transformer, the low voltage side of the high voltage plant transformer is connected to the plant high voltage circuit through an isolating switch, the connecting bus is connected between the plant high voltage circuit and the energy storage bus section, and the energy storage unit is connected to the energy storage bus section;

[0009] The energy storage unit is used to store surplus electric energy in the energy storage bus section. The energy storage unit and the plant high-voltage circuit are used to supply power to the plant power load and black start load of the gas turbine power plant. The energy storage unit is also used for auxiliary frequency regulation of the gas turbine power plant.

[0010] By utilizing the fast and accurate power response capability of the energy storage unit and the advantages of flexible switching and control of multiple modes, the auxiliary frequency regulation function of the energy storage unit is fully utilized, and the energy storage unit is used to store the surplus electric energy in the energy storage bus section as a backup power source for the plant power load and the black start load, ensuring that when the gas turbine unit of the gas turbine power plant is shut down, the electric energy stored in the energy storage unit can be used to black start the gas turbine unit in the shortest time, and power at least part of the plant power load before the black start of the gas turbine unit is completed, so that the in-plant power system of the gas turbine power plant provided by the utility model does not need to be connected to an external backup power line, and the topology optimization of the AGC auxiliary frequency regulation system, the plant power system and the black start system is realized, the construction cost of the gas turbine power plant is reduced, and the energy efficiency level of the gas turbine power plant is improved.

[0011] Furthermore, the energy storage unit includes a plurality of energy storage components sequentially connected to the energy storage bus segment.

[0012] Further, the energy storage assembly includes a battery pack, a first connecting line, an energy storage converter and an energy storage transformer;

[0013] The battery pack is connected to the low-voltage side of the energy storage transformer through the first connecting line, the energy storage converter is arranged on the first connecting line, and the high-voltage side of the energy storage transformer is connected to the energy storage bus section through a high-voltage cable.

[0014] Furthermore, the plant high-voltage circuit includes multiple high-voltage working bus sections, and each of the high-voltage working bus sections is connected to the energy storage bus section through a corresponding connecting bus.

[0015] Furthermore, the plant high-voltage circuit includes two sections of the high-voltage working busbar sections.

[0016] Furthermore, the in-plant power system of the gas turbine power plant also includes a plant power distribution unit, which includes a low-voltage plant transformer and a low-voltage power distribution equipment. The high-voltage side of the low-voltage plant transformer is connected to the plant high-voltage circuit, and the low-voltage side of the low-voltage plant transformer is connected to the low-voltage power distribution equipment. The low-voltage power distribution equipment is used to supply power to the plant power low-voltage load and black start low-voltage load of the gas turbine power plant, and the plant high-voltage circuit is used to supply power to the plant power high-voltage load and black start high-voltage load of the gas turbine power plant.

[0017] Furthermore, the in-plant power system of the gas turbine power plant also includes a wind power generation unit, and the wind power generation unit is connected to the energy storage bus section.

[0018] By coupling the wind power generation unit into the in-plant power system of the gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized, and it also has the advantages of further improving the energy efficiency level in the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0019] Furthermore, the wind power generation unit includes a wind generator set, a second connecting line and an AC converter. The wind generator set is connected to the energy storage bus segment through the second connecting line, and the AC converter is arranged on the second connecting line.

[0020] In another technical solution, the in-plant power system of the gas turbine power plant further includes a photovoltaic power generation unit, and the photovoltaic power generation unit is connected to the energy storage bus section.

[0021] By coupling the photovoltaic power generation unit into the in-plant power system of the gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized, and it also has the advantages of further improving the energy efficiency level in the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0022] Furthermore, the photovoltaic power generation unit includes a photovoltaic power generation group, a third connecting line and an inverter. The photovoltaic power generation group is connected to the energy storage bus segment through the third connecting line, and the inverter is arranged on the third connecting line. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the implementation mode. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0024] Figure 1 is a topological structure diagram of the in-plant power system of the gas turbine power plant in the embodiment;

[0025] 1—gas turbine generator, 2—high-voltage plant transformer, 3—connecting bus, 4—energy storage bus section, 5—battery group, 6—first connecting line, 7—energy storage converter, 8—energy storage transformer, 9—high-voltage working bus section, 10—low-voltage plant transformer, 11—low-voltage power distribution equipment, 12—wind turbine generator set, 13—second connecting line, 14—AC converter, 15—photovoltaic generator set, 16—third connecting line, 17—inverter. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0027] like Figure 1 As shown, this embodiment provides an in-plant power system of a gas turbine power plant, including a gas turbine generator 1, a high-voltage plant transformer 2, a plant high-voltage circuit, a connecting bus 3, an energy storage bus section 4 and an energy storage unit;

[0028] The gas turbine generator 1 is connected to the high voltage side of the high voltage plant transformer 2, the low voltage side of the high voltage plant transformer 2 is connected to the plant high voltage circuit through an isolating switch, the connecting bus 3 is connected between the plant high voltage circuit and the energy storage bus section 4, and the energy storage unit is connected to the energy storage bus section 4;

[0029] The energy storage unit is used to store surplus electric energy in the energy storage bus section 4. The energy storage unit and the high-voltage plant transformer 2 are used to supply power to the plant power load and black start load of the gas turbine power plant. The energy storage unit is also used for auxiliary frequency regulation of the gas turbine power plant.

[0030] By utilizing the fast and accurate power response capability of the energy storage unit and the advantages of flexible switching and control of multiple modes, the auxiliary frequency regulation function of the energy storage unit is fully utilized, and the surplus electric energy stored in the energy storage bus section 4 of the energy storage unit is used as a backup power source for the plant power load and the black start load, ensuring that when the gas turbine unit of the gas turbine power plant is shut down, the electric energy stored in the energy storage unit can be used to black start the gas turbine unit in the shortest time, and power at least part of the plant power load before the black start of the gas turbine unit is completed, so that the in-plant power system of the gas turbine power plant provided by the utility model does not need to be connected to an external backup power line, and the topology optimization of the AGC auxiliary frequency regulation system, the plant power system and the black start system is realized, the construction cost of the gas turbine power plant is reduced, and the energy efficiency level of the gas turbine power plant is improved.

[0031] The in-plant power system of the gas turbine power plant provided in this embodiment proposes a connection structure in which an energy storage unit also serves as the AGC auxiliary frequency regulation of the gas turbine power plant, as well as the backup power supply for the black start load and the plant power load, so as to provide sufficient power support for the gas turbine power plant to realize the auxiliary frequency regulation function, the plant power backup power supply, and the black start.

[0032] Among them, the black start load of the gas turbine power plant includes black start high voltage load and black start low voltage load.

[0033] The power of the energy storage unit is calculated based on the total power of all black start loads of the gas turbine power plant when running at full load.

[0034] The larger value between the capacity required for auxiliary frequency regulation and the capacity required for black start is used as the basis for selecting the capacity of the energy storage unit.

[0035] The in-plant power system of the gas turbine power plant provided in this embodiment accepts the AGC load adjustment command dispatched by the power grid in the grid-connected mode and sends it to the DCS control system of the unit. At the same time, the energy storage unit obtains the AGC command through the power plant remote control unit (RTU) and uses the characteristics of millisecond response rate to first make up for the power difference between the output of the gas turbine generator 1 and the AGC command in a short period of time; after the gas turbine generator 1 responds, the output of the energy storage unit gradually decreases to ensure that the combined output of the energy storage unit and the gas turbine generator 1 is consistent with the AGC command, and prepare for the next AGC command response.

[0036] When the grid dispatching AGC load regulation instruction requires the frequency modulation load to reduce the output of the gas turbine generator 1 (usually reducing the power of the gas turbine generator 1 by 0-3%), the energy storage unit will be in a charging operation state, and the in-plant power system of the gas turbine power plant will charge the energy storage unit through the high-voltage plant transformer 2, the plant high-voltage circuit, the connecting bus 3 and the energy storage bus section 4 in sequence, store electric energy, thereby reducing the unit's on-grid load. When the grid dispatching AGC load regulation instruction requires the frequency modulation load to increase the output of the gas turbine generator 1 (usually reducing the power of the gas turbine generator 1 by 0-3%), the energy storage unit will be in a discharging operation state, the energy storage unit is connected to the energy storage bus section 4, and the energy storage bus section 4 supplies power to the plant high-voltage circuit, reducing the high-voltage side load of the high-voltage plant transformer 2, thereby increasing the on-grid power of the gas turbine generator 1.

[0037] The control system of the energy storage unit performs coordinated frequency regulation control with the power plant RTU and the power plant distributed control system (DCS). When the AGC is put into use, the peak frequency regulation command issued by the dispatching data network is sent to the power plant RTU. After receiving the dispatching frequency regulation command, the RTU will forward it to the DCS. The DCS action controls the output of the gas turbine generator 1 to adjust the target value by adjusting the turbine throttle of the gas turbine generator 1. At the same time, the RTU will also send the AGC frequency regulation command and the real-time output of the gas turbine generator 1 to the control system of the energy storage unit. The control system of the energy storage unit automatically calculates and controls the output of the energy storage unit according to the difference between the command target load and the real-time output of the gas turbine generator 1, and sends the output feedback value of the energy storage unit to the RTU. The RTU merges the unit output with the output of the energy storage system, and uploads the merged output signal to the dispatching data network as the basis for auxiliary service assessment. The energy storage control system automatically controls the difference between the frequency regulation target value and the unit output in real time until the unit output meets the target value requirements of the frequency regulation command, and this frequency regulation ends.

[0038] After the frequency modulation instruction is completed, the control system of the energy storage unit restores the energy storage unit to the standby state, waiting for the arrival of the next AGC frequency modulation instruction from the dispatching side.

[0039] When the in-plant power system of the gas turbine power plant loses power and requires a black start, after the energy storage unit receives the black start command, the energy storage unit is in a discharging operation state, and the energy storage unit is connected to the energy storage bus section 4, and the energy storage bus section 4 supplies power to the plant high-voltage circuit, and the plant high-voltage circuit supplies power to the black start load of the gas turbine power plant, and drives the gas turbine generator 1 to start. After the gas turbine generator 1 is started, the plant high-voltage circuit power is provided through the high-voltage plant transformer 2, and the energy storage unit is converted to a charging operation state. The in-plant power system of the gas turbine power plant charges the energy storage unit through the high-voltage plant transformer 2, the plant high-voltage circuit, the connecting bus 3 and the energy storage bus section 4 in turn, stores electric energy, and prepares for the next AGC command response or black start command.

[0040] In one embodiment, if Figure 1 As shown, the energy storage unit includes a plurality of energy storage components which are sequentially connected to the energy storage busbar segment 4 .

[0041] In one embodiment, if Figure 1 As shown, the energy storage assembly includes a battery pack 5, a first connecting line 6, an energy storage converter 7 and an energy storage transformer 8;

[0042] The battery pack 5 is connected to the low voltage side of the energy storage transformer 8 through the first connecting line 6 , the energy storage converter 7 is arranged on the first connecting line 6 , and the high voltage side of the energy storage transformer 8 is connected to the energy storage bus section 4 through a high voltage cable.

[0043] In one embodiment, the plant high-voltage circuit includes multiple high-voltage working bus sections 9 , and each high-voltage working bus section 9 is connected to the energy storage bus section 4 through a corresponding connecting bus 3 .

[0044] Specifically, Figure 1 As shown, the plant high-voltage circuit includes two sections of high-voltage working bus sections 9.

[0045] In one embodiment, if Figure 1 As shown, the in-plant power system of the gas turbine power plant also includes a plant distribution unit, which includes a low-voltage plant transformer 10 and a low-voltage distribution equipment 11. The high-voltage side of the low-voltage plant transformer 10 is connected to the plant high-voltage circuit, and the low-voltage side of the low-voltage plant transformer 10 is connected to the low-voltage distribution equipment 11. The low-voltage distribution equipment 11 is used to supply power to the plant power low-voltage load and black start low-voltage load of the gas turbine power plant, and the plant high-voltage circuit is used to supply power to the plant power high-voltage load and black start high-voltage load of the gas turbine power plant.

[0046] Preferably, in this embodiment, Figure 1 As shown, the in-plant power system of the gas turbine power plant also includes a wind power generation unit, and the wind power generation unit is connected to the energy storage bus section 4.

[0047] By coupling wind power units into the on-site power system of a gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized. It also has the advantages of further improving the energy efficiency level within the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0048] Among them, Figure 1 As shown, the wind power generation unit includes a wind generator set 12 , a second connecting line 13 and an AC converter 14 . The wind generator set 12 is connected to the energy storage bus section 4 through the second connecting line 13 , and the AC converter 14 is arranged on the second connecting line 13 .

[0049] Preferably, in this embodiment, Figure 1 As shown, the in-plant power system of the gas turbine power plant also includes a photovoltaic power generation unit, which is connected to the energy storage bus section 4.

[0050] By coupling photovoltaic power generation units into the in-plant power system of a gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized. It also has the advantages of further improving the energy efficiency level within the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0051] Among them, Figure 1 As shown, the photovoltaic power generation unit includes a photovoltaic power generation group 15 , a third connecting line 16 and an inverter 17 . The photovoltaic power generation group 15 is connected to the energy storage bus section 4 through the third connecting line 16 , and the inverter 17 is arranged on the third connecting line 16 .

[0052] The in-plant power system of the gas turbine power plant provided by the utility model has at least the following technical effects or advantages:

[0053] 1. By utilizing the fast and accurate power response capability of the energy storage unit and the advantages of flexible switching and control of multiple modes, the auxiliary frequency regulation function of the energy storage unit is fully utilized, and the surplus electric energy stored in the energy storage bus section 4 of the energy storage unit is used as a backup power source for the plant power load and the black start load, ensuring that when the gas turbine unit of the gas turbine power plant is shut down, the electric energy stored in the energy storage unit can be used to black start the gas turbine unit in the shortest time, and power at least part of the plant power load before the black start of the gas turbine unit is completed, so that the in-plant power system of the gas turbine power plant provided by the utility model does not need to be connected to an external backup power line, and the topology optimization of the AGC auxiliary frequency regulation system, the plant power system and the black start system is realized, the construction cost of the gas turbine power plant is reduced, and the energy efficiency level of the gas turbine power plant is improved.

[0054] 2. By coupling wind power generation units into the power system within the gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized. It also has the advantages of further improving the energy efficiency level within the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0055] 3. By coupling the photovoltaic power generation unit into the power system within the gas turbine power plant, the power resource allocation of the gas turbine power plant can be further optimized. It also has the advantages of further improving the energy efficiency level within the plant, saving energy and reducing emissions, and promoting the consumption of new energy.

[0056] The above are only specific application examples of the utility model and do not constitute any limitation to the protection scope of the utility model. Any technical solutions formed by equivalent transformation or equivalent replacement shall fall within the protection scope of the utility model.

Claims

1. An in-plant power system of a gas turbine power plant, characterized in that: It includes gas turbine generator, high-voltage plant transformer, plant high-voltage circuit, connecting bus, energy storage bus section and energy storage unit; The gas turbine generator is connected to the high voltage side of the high voltage plant transformer, the low voltage side of the high voltage plant transformer is connected to the plant high voltage circuit through an isolating switch, the connecting bus is connected between the plant high voltage circuit and the energy storage bus section, and the energy storage unit is connected to the energy storage bus section; The energy storage unit is used to store surplus electric energy in the energy storage bus section. The energy storage unit and the plant high-voltage circuit are used to supply power to the plant power load and black start load of the gas turbine power plant. The energy storage unit is also used for auxiliary frequency regulation of the gas turbine power plant.

2. The in-plant power system of a gas turbine power plant according to claim 1, characterized in that: The energy storage unit includes a plurality of energy storage components sequentially connected to the energy storage bus segment.

3. The in-plant power system of a gas turbine power plant according to claim 2, characterized in that: The energy storage assembly includes a battery pack, a first connecting line, an energy storage converter and an energy storage transformer; The battery pack is connected to the low-voltage side of the energy storage transformer through the first connecting line, the energy storage converter is arranged on the first connecting line, and the high-voltage side of the energy storage transformer is connected to the energy storage bus section through a high-voltage cable.

4. The in-plant power system of a gas turbine power plant according to claim 1, characterized in that: The plant high-voltage circuit includes multiple sections of high-voltage working busbars, and each section of the high-voltage working busbars is connected to the energy storage busbar section through a corresponding connecting busbar.

5. The in-plant power system of a gas turbine power plant according to claim 4, characterized in that: The plant high-voltage circuit includes two sections of high-voltage working busbar sections.

6. The in-plant power system of a gas turbine power plant according to claim 1, characterized in that: It also includes a plant power distribution unit, which includes a low-voltage plant transformer and a low-voltage power distribution equipment. The high-voltage side of the low-voltage plant transformer is connected to the plant high-voltage circuit, and the low-voltage side of the low-voltage plant transformer is connected to the low-voltage power distribution equipment. The low-voltage power distribution equipment is used to supply power to the plant power low-voltage load and black start low-voltage load of the gas turbine power plant, and the plant high-voltage circuit is used to supply power to the plant power high-voltage load and black start high-voltage load of the gas turbine power plant.

7. The in-plant power system of a gas turbine power plant according to claim 1, characterized in that: It also includes a wind power generation unit, which is connected to the energy storage bus section.

8. The in-plant power system of a gas turbine power plant according to claim 7, characterized in that: The wind power generation unit comprises a wind generator set, a second connecting line and an AC converter. The wind generator set is connected to the energy storage bus section through the second connecting line, and the AC converter is arranged on the second connecting line.

9. The in-plant power system of a gas turbine power plant according to claim 1, characterized in that: It also includes a photovoltaic power generation unit, which is connected to the energy storage bus segment.

10. The in-plant power system of a gas turbine power plant according to claim 9, characterized in that: The photovoltaic power generation unit includes a photovoltaic power generation group, a third connecting line and an inverter. The photovoltaic power generation group is connected to the energy storage bus section through the third connecting line, and the inverter is arranged on the third connecting line.

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