CN116260132A - Electric power system - Google Patents

Abstract

The present invention provides an electric power system including: 2n loops and 3n switch modules; wherein n is a positive integer greater than or equal to 2; two adjacent loops are electrically connected through a switch module, and each loop is connected with three switch modules; each loop forms two annular operation modules with other loops through the switch modules, so that when any one switch module in the power system is overhauled, the annular operation of the power system can be still maintained, and at the moment, if one loop breaks down to disconnect the switch modules on the three sides of the loop, the normal operation of other loops can be still maintained, and the power supply reliability of the power system is improved; meanwhile, the technical scheme provided by the invention does not need bus connection, so that complicated bus protection is not required to be configured.

Description

Electric power system

Technical Field

The invention relates to the technical field of power distribution networks, in particular to a power system.

Background

Along with the continuous development of national economy, the requirements on the power supply reliability of a power system are continuously improved. As one of the key points of the power supply reliability, the requirements for the wiring mode of the power system are also higher and higher, especially in the power plant, the cost for stopping the operation of the generator set is higher. The common wiring modes in the current power system are as follows: line transformer bank wiring, bridge wiring, single bus section wiring, double bus section wiring, ring wiring, three-half wiring, etc.

With the continuous increase of voltage level, in order to ensure the power supply reliability of the power system, ring-shaped wiring or three-half wiring is commonly adopted at present. However, for the annular wiring, when a certain circuit breaker is overhauled, the annular wiring runs in an open loop, and at the moment, if a certain circuit fails, when the circuit breakers on two sides of the annular wiring are disconnected, the two circuits can be powered off, so that the accident power-off range is enlarged, and the power supply reliability of a power system is reduced; similarly, for three-half wiring, when a certain breaker is overhauled, the string where the breaker is located is operated in an open loop, if the other loop of the string is failed, when the breakers on two sides of the string are disconnected, the two loops of the string are also powered off, the accident power failure range is enlarged, the power supply reliability of a power system is reduced, and the power supply reliability of the system cannot be guaranteed in the special operation of the system in the two wiring modes. In addition, for three-half wiring, due to the adoption of bus connection, complicated bus protection must be configured, and when a fault occurs in a bus area, all circuit breakers connected with the bus are required to be tripped, so that the power failure range is large.

Disclosure of Invention

The invention provides a power system, which aims to overcome the defects in the prior art and improve the power supply reliability of the power system.

In a first aspect, the present invention provides an electrical power system comprising: 2n loops and 3n switch modules; wherein n is a positive integer greater than or equal to 2;

two adjacent loops are electrically connected through one switch module, and each loop is connected with three switch modules; each loop and other loops form two annular operation modules through the switch module.

Optionally, the switch module includes: the circuit breaker is respectively connected with two first isolating switches at two ends of the circuit breaker;

one end of the first isolating switch is connected with the loop, and the other end of the first isolating switch is connected with the circuit breaker.

Optionally, the power system further includes: a grounding module;

the outgoing line side of the loop is connected with the grounding module, and two ends of the circuit breaker are respectively connected with the grounding module.

Optionally, the power system further includes: 6n current transformer modules;

and two ends of the circuit breaker are respectively connected with one current transformer module.

Optionally, the power system further includes: 2n voltage transformer modules;

and the outgoing line side of the loop is provided with the voltage transformer module.

Optionally, the power system further includes: 2n lightning arresters;

and the outgoing line side of the loop is provided with one lightning arrester.

Optionally, the power system further includes: 2n second isolating switches;

the outgoing line side of the loop is provided with a second isolating switch.

Alternatively, of the three switch modules connected to the loop, there are two switch modules located in different planes.

Optionally, when n=2, the 2n loops and the 3n switch modules form a triangular pyramid structure; wherein 2n loops are positioned at the vertex positions of the triangular pyramid structure.

Optionally, when n is greater than 2, the 2n loops and the 3n switch modules form an n-prismatic table structure; wherein 2n loops are positioned at the vertex positions of the n-prism table.

According to the technical scheme, two adjacent loops are electrically connected through one switch module, each loop is connected with three switch modules, each loop forms two annular operation modules with other loops through the switch modules, so that for each loop, only three-half switch modules are needed, when any one switch module in the power system is overhauled, the annular operation of the power system can be still kept, and at the moment, if a certain loop breaks down to disconnect the switch modules on the three sides of the loop, the normal operation of other loops can be still kept, and the power supply reliability of the power system is improved; meanwhile, the technical scheme provided by the invention does not need bus connection, so that complicated bus protection is not required to be configured.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the invention or to delineate the scope of the invention. Other features of the present invention will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 and fig. 2 are schematic structural diagrams of two power systems according to an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Fig. 1 and fig. 2 are schematic structural diagrams of two power systems according to an embodiment of the present invention, and referring to fig. 1 and fig. 2, an embodiment of the present invention provides a power system, which includes 2n loops and 3n switch modules, where fig. 1 is illustrated by taking a loop including L1, L2, L3 and L4 as an example, and fig. 2 is illustrated by taking a loop including L1, L2, L3, L4, L5 and L6 as an example; wherein n is a positive integer greater than or equal to 2; two adjacent loops are electrically connected through a switch module, and each loop is connected with three switch modules; each loop and other loops form two annular operation modules through a switch module.

The loop is used for connecting a generator set of a power plant, a transformer of a transformer substation and a high-voltage transmission line so as to realize power transmission. The switch module may include, but is not limited to, a circuit breaker, which is responsible for the dual tasks of controlling and protecting, is capable of switching on, carrying and switching off normal state current, and is capable of switching on, carrying and switching off abnormal state (including short circuit) current for a specified period of time. In an alternative embodiment, referring to fig. 1 and 2 in combination, the switch module includes a circuit breaker, fig. 1 is illustrated with the circuit breaker including DL01, DL02, DL03, DL04, DL05 and DL06, fig. 2 is illustrated with the circuit breaker including DL01, DL02, DL03, DL04, DL05, DL06, DL07, DL08 and DL09, and two first disconnecting switches respectively connected to two ends of the circuit breaker, fig. 1 is illustrated with the first disconnecting switches including G011, G012, G021, G022, G031, G032, G041, G042, G051, G052, G061 and G062, and the disconnecting switches including G011, G012, G021, G022, G031, G032, G051, G052, G061, G062, G071, G072, G081, G082 and G092, the first disconnecting switches being connected to one end of the circuit breaker; the first isolating switch is used for physically connecting and isolating a circuit, changing an operation mode and forming a reliable disconnection point, and when the circuit breaker needs to be overhauled, the first isolating switch connected with the two ends of the circuit breaker is switched into a disconnection state so as to disconnect the circuit breaker from a power system.

In an exemplary embodiment, referring to fig. 2, the power system includes 6 loops L1 to L6,9 switch modules, i.e., 9 circuit breakers DL01 to DL09 and 18 first disconnectors G011, G012 to G091, G092, each of which is connected to 3 circuit breakers, and the loop L1 is connected to the circuit breakers DL01, DL02, DL05, respectively, thereby forming 6 loop-shaped operation modules. In the power system, when any one of the circuit breakers is overhauled, 4 annular operation modules are maintained in the power system, and at the moment, if one loop fails, the other 5 loops can still be ensured to maintain normal operation, so that the power supply reliability of the power system is ensured; for a certain circuit, for example, the circuit L1, when any one of the three circuit breakers DL01, DL02, DL05 connected thereto is overhauled, 2 circuit breakers are still connected with the circuit 1, and even if another circuit, for example, any one of the circuits L2 to L5 is failed, at this time, the circuit is at least guaranteed to be in an operation state when the three circuit breakers connected with the failed circuit are tripped, so that the circuit, for example, the circuit L1, is not stopped by the failure of the other circuit. When the circuit breaker needs to be overhauled, the first disconnecting switches at the two ends of the overhauled circuit breaker need to be switched into the disconnection state, and when the circuit breaker DL01 needs to be overhauled, the first disconnecting switches G011 and G012 at the two ends of the circuit breaker DL01 need to be switched into the disconnection state, so that the circuit breaker DL01 is electrically disconnected from a power system, and the safety of operators is ensured.

In this embodiment, when at least one of three circuit breakers connected to a certain circuit is in a closed state, the circuit is indicated to be in an operating state; when three circuit breakers connected with a certain circuit are in an open state, namely the circuit is in a non-operation state, the non-operation state can be a fault state, an overhaul state and the like of the circuit by way of example; whether the circuit breaker is in a closing state or not can be judged through an auxiliary contact of the circuit breaker, an auxiliary contact of a closing relay, an auxiliary contact of a tripping relay and the like. Taking the power system shown in fig. 2 as an example, the loop 1 is connected to the circuit breakers DL01, DL02, DL05, respectively, and when 1 or more of the circuit breakers DL01, DL02, DL05 are in a closed state, the loop L1 is in an operating state; when the circuit breakers DL01, DL02, DL05 are all in the open state, i.e., the circuit L1 is indicated as being in the non-operational state.

In this embodiment, the connection mode of the power system is a bus-free connection mode, and in the selection of the loop protection tripping sequence, the circuit breaker connected with the important loop can be preferentially tripped according to the importance of the connected loop. For example, taking the power system shown in fig. 2 as an example, when 6 loops are all connected with a high-voltage transmission line, if the loop L1 fails, the tripping sequence of the circuit breakers DL01, DL02 and DL05 connected with the loop L1 has no priority, and the tripping sequence of the circuit breakers DL01, DL02 and DL05 is not limited; when the loops L1, L2, L3 are connected to the high-voltage transmission line and the loops L4, L5, L6 are connected to the transformer, if the loop L1 fails, the circuit breaker DL05 connected to the loop L5 may be tripped first, but tripping of the circuit breakers DL01, DL02 is not limited. Correspondingly, the circuit reclosing sequence is opposite to the circuit protection tripping sequence.

In the embodiment, two adjacent loops are electrically connected through one switch module, each loop is connected with three switch modules, and each loop forms two annular operation modules with other loops through the switch modules, so that for each loop, only three-half switch modules are needed, when any one switch module in the power system is overhauled, the annular operation of the power system can be still maintained, and at the moment, if a certain loop breaks down and the switch modules on the three sides of the loop are disconnected, the normal operation of other loops can be still maintained, and the power supply reliability of the power system is improved; meanwhile, the technical scheme provided by the invention does not need bus connection, so that complicated bus protection is not required to be configured.

Optionally, the power system further comprises a grounding module; the outgoing line side of the loop is connected with the grounding module, and two ends of the circuit breaker are respectively connected with the grounding module.

In the embodiment shown in fig. 1 and fig. 2, the grounding module may include a first grounding switch connected to the outgoing line side of each loop and a second grounding switch connected to two ends of each circuit breaker, where fig. 1 is illustrated with the first grounding switch including D160, D260, D360 and D460, the second grounding switch including D0110, D0120, D0210, D0220, D0310, D0320, D0410 and D0420, and fig. 2 is illustrated with the first grounding switch including D110, D120, D130, D140, D150 and D160, and the second grounding switch including D0110, D0120, D0210, D0220, D0310, D0320, D0410, D0420, D0510, D0520, D0610 and D0620; in other embodiments, the grounding module may also include a ground wire to which the outgoing side of each loop and both ends of each circuit breaker are connected, respectively. The grounding module comprises a first grounding switch connected with the outgoing line side of each loop and a second grounding switch connected with the two ends of each circuit breaker respectively, and when a certain loop needs to be overhauled, the first grounding switch on the outgoing line side of the loop is switched into a closing state, so that the outgoing line side of the loop is grounded to ensure the safety of operators during the loop overhauling; when a certain circuit breaker needs to be overhauled, the second grounding switches at two ends of the circuit breaker are switched into a closing state, so that the safety of operators is ensured when the circuit breaker is overhauled; for example, taking the power system shown in fig. 2 as an example, when the circuit 1 needs to be overhauled, the first grounding switch D160 is switched to a closing state, and when the circuit breaker DL01 needs to be overhauled, the second grounding switches D0110 and D0120 at two ends of the circuit breaker DL are switched to a closing state.

In this embodiment, when a certain loop needs to have a power failure, it is necessary to switch three circuit breakers connected to the loop to an off state, then switch first disconnecting switches at two ends of the three circuit breakers connected to the loop to an off state, and then switch a first grounding switch at an outgoing line side of the loop to a on state; when the loop needs to transmit power, the first grounding switch at the outgoing line side of the loop needs to be switched into an off state, then the first isolating switches at two ends of the three circuit breakers connected with the loop are switched into a closing state, and then the three circuit breakers connected with the loop are switched into a closing state. For example, taking the power system shown in fig. 2 as an example, when the circuit 1 needs to have a power outage, the circuit breakers DL01, DL02 and DL05 may be switched to the off state respectively, then the first disconnectors G051, G052, G022, G021, G011 and G012 may be switched to the off state respectively, and then the first grounding switch D160 on the outgoing line side of the circuit 1 may be switched to the on state, where the order of switching the circuit breakers DL01, DL02 and DL05 to the off state is not limited, and the order of switching the first disconnectors D051, G052, G022, G021, G011 and G012 to the off state is not limited; when the loop L1 needs to transmit power, the first grounding switch D160 at the outlet side of the loop L1 can be switched to an off state, then the first isolating switches G051, G052, G022, G021, G011, G012 are respectively switched to a on state, and then the circuit breakers DL01, DL02, DL05 are respectively switched to the on state; the order in which the circuit breakers DL01, DL02, DL05 are switched to the open state or the closed state is not limited, and the order in which the first disconnectors G051, G052, G022, G021, G011, G012 are switched to the open state or the closed state is not limited.

In this embodiment, when a certain breaker needs to have a power failure, the breaker needs to be switched to an off state, then a first isolating switch at two ends of the breaker is switched to an off state, and then a second grounding switch at two ends of the breaker is switched to a on state, so that the breaker is electrically disconnected from the power system, and operations such as maintenance can be performed; when a certain circuit breaker needs to transmit power, the second grounding switches at two ends of the circuit breaker need to be switched into an off state, the first isolating switches at two ends of the circuit breaker need to be switched into a closing state, and then the circuit breaker needs to be switched into a closing state, so that the circuit breaker is connected into a power system, and can normally operate. For example, taking the power system shown in fig. 2 as an example, when the circuit breaker DL01 needs to have a power failure, the circuit breaker DL01 may be switched to an open state, then the first disconnectors G011 and G012 at two ends of the circuit breaker DL01 are respectively switched to an open state, and then the second grounding switches D0120 and D0110 at two ends of the circuit breaker DL01 are respectively switched to a closed state; when the circuit breaker DL01 needs to transmit power, the second grounding switches D0120 and D0110 at two ends of the circuit breaker DL01 may be switched to the open state, then the first disconnecting switches G011 and G012 at two ends of the circuit breaker DL01 may be switched to the closed state, and then the circuit breaker DL01 may be switched to the closed state, where the order of switching the first disconnecting switches G011 and G012 to the open state or the closed state is not limited, and the order of switching the second grounding switches D0120 and D0110 to the open state or the closed state is not limited.

Optionally, the power system further comprises 6n current transformer modules; two ends of the breaker are respectively connected with a current transformer module; fig. 1 illustrates that the current transformer module includes CT011, CT012, CT021, CT022, CT031, CT032, CT041, and CT042, and fig. 2 illustrates that the current transformer module includes CT011, CT012, CT021, CT022, CT031, CT032, CT041, CT042, CT051, CT052, CT061, and CT 062.

The current transformer module can be a current transformer and is used for effectively isolating high-voltage equipment and low-voltage secondary devices of a power system in the electrical aspect, ensuring the safety of personnel and the low-voltage secondary devices, and simultaneously converting large current into standard small current (5A or 1A) in proportion, thereby realizing standardization and miniaturization of measuring instruments, protective equipment and automatic control devices.

Specifically, taking the power system shown in fig. 2 as an example, two ends of each circuit breaker are respectively provided with a current transformer module, and two ends of the circuit breaker DL01 are respectively connected with a current transformer module CT011 and CT012. The protection, measurement and metering currents of the loop are respectively taken from the sum of currents obtained by three current mutual inductance modules which are connected with the loop and far away from the loop, and the protection, measurement and metering currents of the loop L1 are taken from the sum of currents of corresponding windings of the current mutual inductance modules CT011, CT022 and CT 051; the protection, measurement and metering currents of the loop L2 are obtained from the sum of currents of corresponding windings of the current transformer modules CT021, CT032 and CT 061.

Optionally, the power system further comprises 2n voltage transformer modules; a voltage transformer module is arranged on the outgoing line side of the loop; fig. 1 is an illustration of the voltage transformer modules including PT1, PT2, PT3 and PT4, and fig. 2 is an illustration of the voltage transformer modules including PT1, PT2, PT3, PT4, PT5 and PT 6.

The voltage transformer module can be a voltage transformer and is used for effectively isolating high-voltage equipment and low-voltage secondary devices of a power system in the electrical aspect, ensuring the safety of personnel and the low-voltage secondary devices, and simultaneously converting high voltage into standard low voltage (100V or 57.7V) in proportion, thereby realizing standardization and miniaturization of measuring instruments, protective equipment and automatic control devices.

Specifically, taking the power system shown in fig. 2 as an example, each loop is provided with a voltage transformer module on the outgoing line side, and an exemplary voltage transformer module PT1 is provided on the outgoing line side of the loop L1. The synchronous voltage of the circuit breaker is taken from the voltage transformer modules at the outgoing line side of the circuit at two ends of the circuit breaker, and the synchronous voltage of the circuit breaker DL01 is taken from the voltage transformer module PT1 and the voltage transformer module PT3 respectively, and the synchronous voltage of the circuit breaker DL02 is taken from the voltage transformer module PT1 and the voltage transformer module PT2 respectively.

Optionally, the power system further comprises 2n lightning arresters; an arrester is arranged on the outgoing line side of the loop; fig. 1 is an illustration of an arrester comprising LA1, LA2, LA3 and LA4, and fig. 2 is an illustration of an arrester comprising LA1, LA2, LA3, LA4, LA5 and LA 6.

The lightning arrester is used for protecting electrical equipment from high transient overvoltage and operation overvoltage hazards during lightning strike, and limiting the freewheel time and freewheel amplitude. An arrester is disposed on the outgoing line side of each loop, and illustratively, taking the power system shown in fig. 2 as an example, an arrester LA1 is disposed on the outgoing line side of the loop L1, and an arrester LA2 is disposed on the outgoing line side of the loop L2.

Optionally, the power system further comprises 2n second isolating switches (not shown in the figure); the outgoing line side of the loop is provided with a second isolating switch.

The second isolating switch is used for physically connecting and isolating the circuit, changing the operation mode and forming a reliable disconnection point; when a certain loop needs to be overhauled, the switch module connected with the loop can be switched into the disconnection state firstly, then the second isolating switch at the outgoing line side of the loop is switched into the disconnection state, at the moment, the switch module connected with the loop can be switched into the closing state again, so that other loops still have 3 switch modules connected with the switch module, and the power supply reliability of a power supply system is improved.

Alternatively, of the three switching modules connected to the circuit, there are two switching modules located in different planes.

Specifically, two switch modules are located on different planes in three switch modules connected with the loop, so that the loop and the switch modules connected with the loop can be distributed in a layered manner in space, and the land area is greatly saved.

In an alternative embodiment, referring to fig. 1, when n=2, 2n loops and 3n switch modules form a triangular pyramid structure; wherein, 2n loops are positioned at the vertex positions of the triangular pyramid structure.

In the embodiment shown in fig. 1, when n=2, that is, the power system has 4 loops and 6 switch modules, the 4 loops are respectively located at the vertex positions of the triangular pyramid structure, where the three loops can be arranged on the same level, the other loop is located at the remaining vertex position of the triangular pyramid, and the 6 switch modules respectively form 6 edges of the triangular pyramid, so that the stacking arrangement of the power system can be realized, and the land area can be saved.

In another alternative embodiment, when n > 2, 2n loops and 3n switch modules form an n-sided mesa structure; wherein, 2n loops are located at the vertex positions of the n prismatic tables.

In an exemplary embodiment, fig. 2 illustrates a schematic structural diagram of the power system when n=3, as shown in fig. 2, 6 loops and 9 switch modules form a triangular platform structure, where three loops may be disposed on a same level, and located at a bottom vertex position of the triangular platform, and the other three loops are disposed on another level, and located at a top vertex position of the triangular platform, and 9 switch modules respectively form 9 edges of the triangular platform structure.

In other embodiments, when n=4, the power system includes 8 loops and 12 switch modules, where the 8 loops and the 12 switch modules form a quadrangular frustum structure, where the four loops may be disposed on a same level and located at a bottom vertex position of the quadrangular frustum, the other four loops are disposed on another level and located at a top vertex position of the quadrangular frustum, and the 12 switch modules respectively form 12 edges of the quadrangular frustum structure.

In other embodiments, if the local land feature cost is not high, the arrangement mode of the power system may be properly adjusted to be planar horizontal arrangement, for example, in the embodiment shown in fig. 2, the power system may also be arranged horizontally according to the structure of the power system shown in fig. 2, so that the difficulty in arranging the power system may be reduced.

The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims (10)

1. An electrical power system, comprising: 2n loops and 3n switch modules; wherein n is a positive integer greater than or equal to 2;

two adjacent loops are electrically connected through one switch module, and each loop is connected with three switch modules; each loop and other loops form two annular operation modules through the switch module.

2. The power system of claim 1, wherein the switch module comprises: the circuit breaker is respectively connected with two first isolating switches at two ends of the circuit breaker;

one end of the first isolating switch is connected with the loop, and the other end of the first isolating switch is connected with the circuit breaker.

3. The power system of claim 2, further comprising: a grounding module;

the outgoing line side of the loop is connected with the grounding module, and two ends of the circuit breaker are respectively connected with the grounding module.

4. The power system of claim 2, further comprising: 6n current transformer modules;

and two ends of the circuit breaker are respectively connected with one current transformer module.

5. The power system of claim 1, further comprising: 2n voltage transformer modules;

and the outgoing line side of the loop is provided with the voltage transformer module.

6. The power system of claim 1, further comprising: 2n lightning arresters;

and the outgoing line side of the loop is provided with one lightning arrester.

7. The power system of claim 1, further comprising: 2n second isolating switches;

the outgoing line side of the loop is provided with a second isolating switch.

8. The power system of claim 1, wherein of the three switch modules connected to the loop, there are two of the switch modules that lie in different planes.

9. The power system of claim 8, wherein when n = 2, the 2n loops and the 3n switch modules form a triangular pyramid structure; wherein 2n loops are positioned at the vertex positions of the triangular pyramid structure.

10. The power system of claim 8, wherein when n > 2, the 2n loops and the 3n switch modules form an n-sided land structure; wherein 2n loops are positioned at the vertex positions of the n-prism table.

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