A gas turbine starting device and a gas turbine power generation set

Abstract

The present invention provides a gas turbine starting device and a gas turbine generating set. The gas turbine generating set includes the starting device. The starting device is provided with a first electrical circuit and a second electrical circuit, which are respectively used for connecting a first starting motor and a second starting motor to a first storage battery. When the system starts, a control module controls the conduction states of the first electrical circuit and the second electrical circuit to control the first starting motor and the second starting motor to start with current limiting in sequence, and after both the first starting motor and the second starting motor start, the limitation on the working current of the first starting motor and the second starting motor is removed. The gas turbine starting device and the gas turbine generating set provided by the present invention gradually increase the starting driving force of the gas turbine, can reduce the starting current when the starting motor starts, reduce the arcing risk of the contact switch in the electrical circuit, and improve the system reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbine generator sets, and particularly to a gas turbine starting device and a gas turbine generator set. Background Art

[0002] Gas turbines have the advantages of small volume, light weight, fast start-up, convenient maintenance, reliable operation, high degree of automation, etc. The power of micro and light gas turbines is usually within 50MW, and they can be used in industrial power generation, ship power, pipeline boosting, tank locomotives, distributed power generation, combined heat and power supply and other scenarios.

[0003] The power of heavy gas turbines is above 50MW, and they are mainly used as fixed generator sets on land, such as urban power grids. Compared with traditional diesel generator sets, gas turbine generator sets have many advantages such as small device volume, less land occupation, small vibration, short installation period, and high operation reliability.

[0004] In terms of the starting system, compared with diesel generator sets, the starting motor of gas turbine generator sets runs for a long time and has a relatively large starting current. When the starting current is at its maximum, it can reach 2500A. When a gas turbine generator set is used as a standby power supply, it is necessary to consider the power supply problem of the starting motor during the starting process and the reliability problem during the starting process. Summary of the Invention

[0005] Based on this, the purpose of the present invention is to provide a gas turbine starting device and a gas turbine generator set to improve the reliability during the starting process of the gas turbine generator set.

[0006] On the one hand, the present invention provides a gas turbine starting device for starting the rotor of a gas turbine, including: a first starting motor and a second starting motor, and:

[0007] A first electrical circuit for connecting the first starting motor in series with a first battery, and a first starting resistor is connected in series in the first electrical circuit;

[0008] A second electrical circuit for connecting the second starting motor in series with the first battery, and a second starting resistor is connected in series in the second electrical circuit;

[0009] A control module including a starting controller, a first controller, and a second controller powered by the first battery and the second battery;

[0010] Wherein, both the first starting motor and the second starting motor are drivingly connected to the rotor of the gas turbine, and the output voltage of the first battery is greater than the output voltage of the second battery;

[0011] When the start controller is set to the start state, the first electrical circuit is turned on and the first start motor starts.

[0012] After the start controller is set to the start state and after a first delay time, the first controller is set to the start state, causing the second electrical circuit to be turned on and the second start motor to start.

[0013] After the start controller is set to the start state and after a second delay time, the second controller is in the start state, causing the first start resistor and the second start resistor to be short-circuited.

[0014] The second delay time is greater than the first delay time.

[0015] Optionally, the start controller includes a first power switch, a first start switch, a first drive relay, and a first start relay, where

[0016] The relay coils of the first power switch, the first start switch, and the first drive relay are sequentially connected in series between the positive terminal and the negative terminal of the second battery.

[0017] The contact switch of the first drive relay and the relay coil of the first start relay are sequentially connected in series between the positive terminal and the negative terminal of the first battery.

[0018] The contact switch of the first drive relay is connected in series in the first electrical circuit.

[0019] Optionally, the first controller includes a first delay relay, a second drive relay, and a second start relay, where

[0020] The relay coil of the first delay relay is connected in series with the second battery through the first power switch.

[0021] The contact switch of the first delay relay and the relay coil of the second drive relay are connected in series with the second battery through the first power switch.

[0022] The contact switch of the second drive relay and the relay coil of the second start relay are sequentially connected in series between the positive terminal and the negative terminal of the first battery.

[0023] The contact switch of the second start relay is connected in series in the second electrical circuit.

[0024] When the relay coil of the first delay relay is connected to the second battery and after the first delay time, the contact switch of the first delay relay is set to the conducting state.

[0025] Optionally, the second controller includes a second time-delay relay, a third drive relay, a third start relay, and a fourth start relay, where

[0026] The relay coil of the second time-delay relay is connected in series with the second battery through the first power switch;

[0027] The contact switch of the second time-delay relay and the relay coil of the third drive relay are connected in series with the second battery through the first power switch;

[0028] The first set of contact switches of the third drive relay and the relay coil of the third start relay are successively connected in series between the positive terminal and the negative terminal of the first battery;

[0029] The contact switch of the third start relay is connected in parallel with the first starting resistor;

[0030] The second set of contact switches of the third drive relay and the relay coil of the fourth start relay are successively connected in series between the positive terminal and the negative terminal of the first battery;

[0031] The contact switch of the fourth start relay is connected in parallel with the second starting resistor;

[0032] When the relay coil of the second time-delay relay is connected to the second battery and after the second delay time, the contact switch of the second time-delay relay is set to the conducting state.

[0033] Optionally, the first drive relay, the second drive relay, and the third drive relay are all load relays.

[0034] Optionally, the two sets of contact switches of the first drive relay, the second drive relay, and the third drive relay are all connected in series in the corresponding electrical circuits.

[0035] Optionally, the first disconnect switch of the first starting motor includes two sets of first contact switches connected in parallel with each other, and the contact switches within each set of the first contact switches are connected in series with each other;

[0036] The second disconnect switch of the second starting motor includes two sets of second contact switches connected in parallel with each other, and the contact switches within each set of the second contact switches are connected in series with each other.

[0037] Optionally, the series circuit of the first starting resistor and the first starting motor is also connected in parallel with the starting fuel pump of the gas turbine to start the starting fuel pump of the gas turbine synchronously when the first starting motor starts.

[0038] Optionally, when the rotational speed of the rotor reaches a preset reference speed, the first electrical circuit and the second electrical circuit are in an open state, where the reference speed is 50% to 60% of the rated speed of the gas turbine.

[0039] According to another aspect of the present invention, there is provided a gas turbine generator set, including the gas turbine starting device provided by the present invention.

[0040] The first electrical circuit and the second electrical circuit of the gas turbine starting device provided by the present invention are respectively used for connecting the first starting motor and the second starting motor to the first storage battery. The control module uses the first storage battery and the second storage battery as the working power supply. When the system is started, the control module controls the conduction states of the first electrical circuit and the second electrical circuit to control the first starting motor and the second starting motor to start with current limiting in sequence. After both the first starting motor and the second starting motor are started, the limitation of the working current of the first starting motor and the second starting motor is released. The gas turbine starting device provided by the present invention can reduce the starting current of the system electrical circuit, reduce the arcing risk of the contact switch in the electrical circuit, improve the system reliability, and while the two starting motors achieve current sharing of the starting current, they can also ensure the driving ability of the gas turbine rotor, further improving the starting reliability of the system.

[0041] The gas turbine generator set of the present invention includes the gas turbine starting device of the present invention, and has a good arc extinguishing effect during system startup, guaranteed starting ability, and high overall reliability. Description of the Drawings

[0042] Figure 1 It is a schematic diagram of the main electrical circuit structure of the gas turbine starting device in the embodiment of the present invention;

[0043] Figure 2 It is a partial structural schematic diagram of the control module of the gas turbine starting device in the embodiment of the present invention;

[0044] Figure 3 It is a partial structural schematic diagram of the control module of the gas turbine starting device in the embodiment of the present invention.

[0045] Description of the Main Component Symbols:

[0046] First storage battery 11 Second storage battery 12 First starting motor M1 Second starting motor M2 First disconnecting switch LSB1 Second disconnecting switch LSB2 First starting relay KM1 Second starting relay KM2 Third starting relay KM3 Fourth starting relay KM4 First starting resistor R1 Second starting resistor R2 Starting fuel pump 20 First power switch Q1 First time-delay relay KT1 Second time-delay relay KT2 First starting switch KA1 First driving relay K11 Second driving relay K12 Third driving relay K13 Second power switch Q2

[0047] The following specific embodiments will further illustrate the present invention in conjunction with the above drawings. Specific Embodiments

[0048] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0049] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0051] Please refer to Figure 1 、 Figure 2 and Figure 3 , which shows a schematic structural diagram of a gas turbine starting device in an embodiment of the present invention.

[0052] The gas turbine starting device in this embodiment is used for starting the rotor of a gas turbine. It uses the first battery 11 and the second battery 12 as the working power supply and mainly includes: a first starting motor M1 and a second starting motor M2, and: a first electrical circuit for connecting the first starting motor M1 in series with the first battery 11, and a first starting resistor R1 is connected in series in the first electrical circuit; a second electrical circuit for connecting the second starting motor M2 in series with the first battery 11, and a second starting resistor R2 is connected in series in the second electrical circuit; a control module, including a starting controller, a first controller, and a second controller that use the first battery 11 and the second battery 12 as the working power supply.

[0053] The first starter motor M1 and the second starter motor M2 are both drivingly connected to the rotor of the gas turbine, and the output voltage of the first battery 11 is greater than the output voltage of the second battery 12. In a specific embodiment, the first battery 11 is a battery pack, and its output voltage is 60V DC, and the output voltage of the second battery 12 is 24V DC. The parameters of the first starter motor M1 and the second starter motor M2 are consistent, and their rated working voltage is 60V DC, the rated working power is 40kW, and the maximum working current can reach 2500A. They have large output torque and strong ability to start the rotor of the gas turbine.

[0054] Among them, the voltage drop change of the first battery 11 during long-term high-current discharge is small, which can ensure the high-current driving capability of the first starter motor M1 and the second starter motor M2, improve the consistency between the actual working state of the first starter motor M1 and the second starter motor M2 and the expected effect during the starting process of the gas turbine, and improve the controllability and reliability of the system.

[0055] When the starting controller is set to the starting state, the first electrical circuit is turned on, and the first starting motor starts M1; after the starting controller is set to the starting state and after a first delay time, the first controller is set to the starting state, the second electrical circuit is turned on, and the second starting motor starts M2; after the starting controller is set to the starting state and after a second delay time, the second controller is in the starting state, the first starting resistor R1 and the second starting resistor R2 are short-circuited, so as to increase the power supply current of the first starting motor M1 and the second starting motor M2, increase the rotation speed, and increase the driving force on the gas turbine rotor.

[0056] In this embodiment, the second delay time is greater than the first delay time, so that after both starter motors are started, the working current restrictions of the two starter motors are released simultaneously. In an optional embodiment, multiple delay control chains can be set so that the starting time of the first starter motor M1 and the working current restriction release time of the second starter motor M2 can be controlled separately.

[0057] The starting process of the gas turbine starting device provided by the present invention includes, in sequence, current limiting starting of the first starting motor, current limiting starting of the second starting motor, releasing the current limit of the first starting motor and the second starting motor, starting the starting motor in the current limiting mode, and then increasing the working current of the starting motor, thereby gradually increasing the starting driving force of the gas turbine rotor. While ensuring the final driving force, the starting current of the control switch in the electrical circuit can be reduced, the surge current during startup can be reduced, and the safety of system startup can be improved.

[0058] In this embodiment, the start controller includes a first power switch Q1, a first start switch KA1, a first drive relay K11, and a first start relay KM1.

[0059] Among them, the relay coils of the first power switch Q1, the first start switch KA1, and the first drive relay K11 are sequentially connected in series between the positive terminal and the negative terminal of the second storage battery; the contact switch of the first drive relay K11 and the relay coil of the first start relay KM1 are sequentially connected in series between the positive terminal and the negative terminal of the first storage battery 11; the contact switch of the first drive relay KM1 is connected in series in the first electrical circuit.

[0060] The first controller includes a first time-delay relay KT1, a second drive relay K12, and a second start relay KM2.

[0061] Among them, the relay coil of the first time-delay relay KT1 is connected in series with the second storage battery 12 through the first power switch Q1; the contact switch of the first time-delay relay KT1 and the relay coil of the second drive relay K12 are connected in series with the second storage battery 12 through the first power switch Q1; the contact switch of the second drive relay K12 and the relay coil of the second start relay KM2 are sequentially connected in series between the positive terminal and the negative terminal of the first storage battery 11; the contact switch of the second start relay KM2 is connected in series in the second electrical circuit.

[0062] When the relay coil of the first time-delay relay KT1 is connected to the second storage battery 12 and after the first time-delay period, the contact switch of the first time-delay relay KT1 is set to the conducting state, so as to control the contact switch of the second start relay KM2 to conduct through the control chain of the first controller, so as to conduct the second electrical circuit and start the second start motor M2.

[0063] The second controller includes a second time-delay relay KT2, a third drive relay K13, a third start relay KM3, and a fourth start relay KM4.

[0064] Among them, the relay coil of the second delay relay KT2 is connected in series with the second storage battery 12 through the first power switch Q1; the contact switch of the second delay relay KT2 and the relay coil of the third drive relay K13 are connected in series with the second storage battery 12 through the first power switch Q1; the first set of contact switches of the third drive relay K13 and the relay coil of the third start relay KM3 are successively connected in series between the positive terminal and the negative terminal of the first storage battery 11; the contact switch of the third start relay KM3 is connected in parallel with the first start resistor R1; the second set of contact switches of the third drive relay K13 and the relay coil of the fourth start relay KM4 are successively connected in series between the positive terminal and the negative terminal of the first storage battery 11; the contact switch of the fourth start relay KM4 is connected in parallel with the second start resistor R2.

[0065] When the relay coil of the second delay relay KT2 is connected to the second storage battery 12 and after the second delay time, the contact switch of the second delay relay KT2 is set to the conducting state, so as to control the contact switches of the third start relay KM3 and the fourth start relay KM4 to conduct through the control chain of the second controller, short-circuit the first start resistor R1 and the second start resistor R2, improve the output power of the first start motor M1 and the second start motor M2, improve the rotor starting ability of the gas turbine, and reduce the starting time.

[0066] In this embodiment, the parameters of the first start relay KM1, the second start relay KM2, the third start relay KM3, and the fourth start relay KM4 are: the rated coil voltage is DC60V, the rated coil current is 3A, and the rated contact current is 2000A. The corresponding first drive relay K11, the second drive relay K12, and the third drive relay K13 are all load relays, and their contacts can meet the DC working conditions of 60V - 3A.

[0067] Furthermore, the two sets of contact switches of the first drive relay K11, the second drive relay K12, and the third drive relay K13 are all connected in series in the corresponding electrical circuits, which can further reduce the risk of arc burning of the DC electrical circuits corresponding to their contacts and improve the system reliability.

[0068] In this embodiment, the first disconnection switch LSB1 of the first starting motor M1 includes two groups of first contact switches connected in parallel with each other, and the contact switches within each group of the first contact switches are connected in series with each other; the second disconnection switch LSB2 of the second starting motor M2 includes two groups of second contact switches connected in parallel with each other, and the contact switches within each group of the second contact switches are connected in series with each other. Among them, in this embodiment, the working circuits of the first starting motor M1 and the second starting motor M2 are both DC circuits, and the contacts of the disconnection switches are designed in the above series-parallel structure, which can increase the working current that the disconnection switch can withstand through the parallel structure, reduce the arcing in the DC circuit through the series connection of two groups of contacts, improve the arc extinguishing ability of the system, and improve the reliability of the system.

[0069] In this embodiment, the series circuit of the first starting resistor R1 and the first starting motor M1 is also connected in parallel with the starting fuel pump 20 of the gas turbine to start the starting fuel pump 20 of the gas turbine synchronously when the first starting motor M1 starts.

[0070] When both the first starting motor M1 and the second starting motor M2 run at an increased speed bypassing the starting resistor, the rotor speed of the gas turbine continues to increase. When the rotor speed reaches the preset reference speed, and the turbine of the gas turbine already has enough remaining power for the unit to increase speed, the starting motor can be stopped, and the starting device controls the first electrical circuit and the second electrical circuit to be disconnected. Among them, the reference speed is 50% to 60% of the rated speed of the gas turbine.

[0071] In this embodiment, it further includes a second power switch Q2. The second power switch Q2 is arranged on the positive output path of the first storage battery 11. When the second power switch Q2 is disconnected, the power supply circuit of the first storage battery 11 to the first starting relay KM1 to the fourth starting relay KM4 can be turned off.

[0072] In an alternative embodiment, the relay coils of the first time-delay relay KT1 and the second time-delay relay KT2 are connected from the intermediate node between the first starting switch KA1 and the relay coil of the first driving relay K11 to the negative terminal of the second storage battery 12, so that the relay coils of the first driving relay K11, the first time-delay relay KT1, and the second time-delay relay KT2 are synchronously connected to the second storage battery 12 through the first starting switch KA1, ensuring that the starting moments of the first delay time and the second delay time are synchronized with the system starting moment.

[0073] In this embodiment, the first start switch KA1 is connected to the second battery 12. The voltage of the second battery 12 is a safe voltage relative to the human body. The first start switch KA1 can adopt a common switch structure such as a push-button switch or a relay structure, and implement a software switch according to the state of the start command provided by the electronic control system to achieve software start control of the gas turbine starting device. Specifically, for example, when the start command is valid, the relay structure controls the first start switch KA1 to close; when the start command is invalid, the relay structure controls the first start switch KA1 to open, and at the same time resets the timing states of the first delay relay KT1 and the second delay relay KT2 to prepare for the next start.

[0074] The first power switch Q1 and the second power switch Q2 are, for example, circuit breakers.

[0075] The present invention also provides a gas turbine generator set, including the gas turbine starting device of the present invention. The starting device gradually improves the ability to speed up and drive the rotor of the gas turbine. The starting current of the starting motor of the starting device is low, the inrush current during starting is small, the arc suppression performance is good, and the reliability is high, thereby improving the reliability of the gas turbine generator set.

[0076] In a specific embodiment, the first delay time is 6 seconds and the second delay time is 9.3 seconds. The starting time of the corresponding gas turbine is shortened by 2 to 3 seconds compared with the starting time of the gas turbine in the prior art. That is, although the gas turbine starting device of the present invention reduces the driving current at the initial stage of starting of the starting motor, its starting ability for the gas turbine is still guaranteed, and even the starting speed is faster. In actual operation, the first delay time and the second delay time can be adaptively adjusted according to specific requirements, and the present application does not make special restrictions on this.

[0077] In the above embodiments of the present application, when the coils of the relays are not powered on, their contact switches (the contacts connected to the corresponding electrical circuits, for example, using their common contacts and normally open contacts as the contact switches connected to the electrical circuits) are in the off state; when the coils of the relays are powered on, their contact switches are in the on state.

[0078] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0079] The above-described embodiments merely represent several specific implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention shall be subject to the appended claims.

Claims

1. A gas turbine starting device for starting the rotor of a gas turbine, characterized in that, Comprising: A first starting motor and a second starting motor, and: A first electrical circuit for connecting the first starting motor in series with a first storage battery, and a first starting resistor is connected in series in the first electrical circuit; A second electrical circuit for connecting the second starting motor in series with the first storage battery, and a second starting resistor is connected in series in the second electrical circuit; A control module, including a starting controller, a first controller, and a second controller powered by the first storage battery and the second storage battery; Wherein, both the first starting motor and the second starting motor are drivingly connected to the rotor of the gas turbine, and the output voltage of the first storage battery is greater than the output voltage of the second storage battery; When the starting controller is set to the starting state, the first electrical circuit is turned on and the first starting motor starts; After the starting controller is set to the starting state and after a first delay time, the first controller is set to the starting state to turn on the second electrical circuit and start the second starting motor; After the starting controller is set to the starting state and after a second delay time, the second controller is in the starting state to short-circuit the first starting resistor and the second starting resistor; The second delay time is greater than the first delay time.

2. The gas turbine starting device according to claim 1, wherein The starting controller includes a first power switch, a first starting switch, a first driving relay, and a first starting relay, wherein, The first power switch, the first starting switch, and the relay coil of the first driving relay are sequentially connected in series between the positive terminal and the negative terminal of the second storage battery; The contact switch of the first driving relay and the relay coil of the first starting relay are sequentially connected in series between the positive terminal and the negative terminal of the first storage battery; The contact switch of the first driving relay is connected in series in the first electrical circuit.

3. The gas turbine starting device according to claim 2, characterized in that, The first controller includes a first delay relay, a second driving relay, and a second starting relay, wherein, The relay coil of the first delay relay is connected in series with the second storage battery through the first power switch; The contact switch of the first delay relay and the relay coil of the second driving relay are connected in series with the second storage battery through the first power switch; The contact switch of the second driving relay and the relay coil of the second starting relay are sequentially connected in series between the positive terminal and the negative terminal of the first storage battery; The contact switch of the second starting relay is connected in series in the second electrical circuit; When the relay coil of the first delay relay is connected to the second storage battery and after the first delay time, the contact switch of the first delay relay is set to the conducting state.

4. The gas turbine starting device according to claim 3, characterized in that, The second controller includes a second delay relay, a third driving relay, a third starting relay, and a fourth starting relay, wherein, The relay coil of the second delay relay is connected in series with the second storage battery through the first power switch; The contact switch of the second delay relay and the relay coil of the third driving relay are connected in series with the second storage battery through the first power switch; The first set of contact switches of the third drive relay and the relay coil of the third start relay are sequentially connected in series between the positive terminal and the negative terminal of the first battery; The contact switch of the third start relay is connected in parallel with the first start resistor; The second set of contact switches of the third drive relay and the relay coil of the fourth start relay are sequentially connected in series between the positive terminal and the negative terminal of the first battery; The contact switch of the fourth start relay is connected in parallel with the second start resistor; When the relay coil of the second delay relay is connected to the second battery and after the second delay time, the contact switch of the second delay relay is set to the conducting state.

5. The gas turbine starting device according to claim 4, wherein The first drive relay, the second drive relay and the third drive relay are all load relays.

6. The gas turbine starting device according to claim 4 or 5, wherein The two sets of contact switches of the first drive relay, the second drive relay and the third drive relay are respectively connected in series in the corresponding electrical circuits.

7. The gas turbine starting device according to claim 1, wherein The first disconnect switch of the first starting motor includes two sets of first contact switches connected in parallel with each other, and the contact switches within each set of the first contact switches are connected in series with each other; The second disconnect switch of the second starting motor includes two sets of second contact switches connected in parallel with each other, and the contact switches within each set of the second contact switches are connected in series with each other.

8. The gas turbine starting device according to claim 1, wherein The series circuit of the first start resistor and the first start motor is also connected in parallel with the start fuel pump of the gas turbine to synchronously start the start fuel pump of the gas turbine when the first start motor starts.

9. The gas turbine starting device according to claim 1, wherein When the rotor speed reaches a preset reference speed, the first electrical circuit and the second electrical circuit are in the open state, wherein the reference speed is 50% to 60% of the rated speed of the gas turbine.

10. A gas turbine generator set, characterized in that, Including the gas turbine starting device according to any one of claims 1 to 9.

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