阅读说明：本技术 一种基于四段母线供电的站用电系统及其控制方法 (Station power utilization system based on four-section bus power supply and control method thereof ) 是由 王乙斐 肖军 叶磊 王华军 陈昌旭 段涛 蔡彬 陈晓明 严文海 潘祥园 于 2021-09-23 设计创作，主要内容包括：本发明涉及变电站技术领域,具体涉及一种基于四段母线供电的站用电系统及其控制方法。包括第一母线～第四母线、第一变压器、第二变压器和备用发电机,第一变压器通过第一进线断路器连接至第一母线,第二变压器和备用发电机分别通过第二进线断路器、第三进线断路器连接至第二母线,第一母线与第二母线之间通过第一联络断路器连接,第一母线与第三母线之间通过第二联络断路器连接,第二母线与第四母线之间通过第三联络断路器连接,第一母线和第二母线上分别连接有重要负载,第三母线和第四母线上分别连接有非重要负载。(The invention relates to the technical field of transformer substations, in particular to a station power utilization system based on four-section bus power supply and a control method thereof. The first transformer is connected to the first bus through a first incoming line breaker, the second transformer and the standby generator are connected to the second bus through a second incoming line breaker and a third incoming line breaker respectively, the first bus and the second bus are connected through a first interconnection breaker, the first bus and the third bus are connected through a second interconnection breaker, the second bus and the fourth bus are connected through a third interconnection breaker, important loads are connected to the first bus and the second bus respectively, and non-important loads are connected to the third bus and the fourth bus respectively.)

1. The utility model provides a station power consumption system based on four sections generating lines power supplies which characterized in that: including first generating line ~ fourth generating line, first transformer, second transformer and stand-by generator, first transformer is connected to first generating line through first inlet wire circuit breaker, second transformer and stand-by generator are connected to the second generating line through second inlet wire circuit breaker, third inlet wire circuit breaker respectively, be connected through first contact circuit breaker between first generating line and the second generating line, be connected through second contact circuit breaker between first generating line and the third generating line, be connected through third contact circuit breaker between second generating line and the fourth generating line, be connected with important load on first generating line and the second generating line respectively, be connected with non-important load on third generating line and the fourth generating line respectively.

2. The station power system based on four-section bus power supply of claim 1, wherein: the voltage relay is connected between the phase B and the phase N of the second bus and used for being switched on when the bus is in voltage loss.

3. The station power system based on four-section bus power supply of claim 1, wherein: the standby generator is a diesel generator.

4. The station power system based on four-section bus power supply of claim 1, wherein: the first incoming line circuit breaker, the second incoming line circuit breaker, the third incoming line circuit breaker and the first interconnection circuit breaker are all controlled by a BZT device or an ATS device.

5. The station power system based on four-section bus power supply of claim 1, wherein: when the bus is in voltage loss, the second and third contact breakers are both opened.

6. A control method of the station power system based on the four-segment bus power supply according to claim 1, characterized in that:

when the first transformer and the second transformer both normally operate, the first incoming line breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the first interconnection breaker and the third interconnection breaker are in an opening state;

when the first transformer is abnormal and the second transformer normally operates, the second incoming line breaker, the first interconnection breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the first incoming line breaker and the third incoming line breaker are in an opening state;

when the first transformer normally operates and the second transformer is abnormal, the first incoming line breaker, the first interconnection breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the second incoming line breaker and the third incoming line breaker are in an opening state;

when first transformer and second transformer were all unusual, first interconnection circuit breaker, third incoming line circuit breaker were in the combined floodgate state, and first incoming line circuit breaker, second interconnection circuit breaker, third interconnection circuit breaker are in the separating brake state.

7. The station power system based on four-section bus power supply of claim 6, wherein: and when the first incoming line breaker is switched on, the first interconnection breaker is required to be switched off or the second incoming line breaker and the third incoming line breaker are required to be switched off, and if the first incoming line breaker is not switched on, the first incoming line breaker is not switched on.

8. The station power system based on four-section bus power supply of claim 6, wherein: and when the second incoming line breaker is switched on, the third incoming line breaker is required to be switched off, the first incoming line breaker or the first interconnection breaker is switched off, and if the third incoming line breaker or the first interconnection breaker is not switched on, the second incoming line breaker is not switched on.

9. The station power system based on four-section bus power supply of claim 6, wherein: and when the third incoming line breaker is switched on, the first incoming line breaker and the second incoming line breaker are required to be switched off uniformly, the bus is in no-voltage state, the second connecting breaker and the third connecting breaker are switched off uniformly, and if the third connecting breaker is not required to be switched on, the third incoming line breaker is not switched on.

10. The station power system based on four-section bus power supply of claim 6, wherein: and when the first interconnection breaker is switched on, the first incoming line breaker is required to be switched off or the second incoming line breaker and the third incoming line breaker are required to be switched off, and if the first incoming line breaker is not required to be switched on, the first interconnection breaker is not switched on.

Technical Field

The invention relates to the technical field of transformer substations, in particular to a station power utilization system based on four-section bus power supply and a control method thereof.

Background

The power system of the alternating current station of the transformer substation provides power support for the alternating current and direct current loads in the transformer substation, and normal operation of the main transformer, the primary equipment and the protection device is guaranteed. In recent years, with the continuous improvement of the requirements of stable operation and sustainable development of a power grid, higher requirements are also put on the reliability and safety of a power utilization system of a substation. Overseas substations usually adopt the design concept of 'unattended operation and little person watching', and domestic substations are gradually implementing the mode. When a station power utilization system breaks down, if an operator does not find and process the station power utilization system in time, the normal work of a transformer substation can be directly influenced, and economic loss is caused. In order to avoid the accidents, how to select a station power utilization wiring mode with high reliability and high automation is a technical key in the engineering design of the transformer substation.

The typical station power connection scheme adopts a two-section bus connection mode, which is mainly divided into two types.

In the power supply system I shown in fig. 1, two segments of buses are normally operated in a split manner, and when one power supply or one power supply fails, the other power supply can bear the whole load; when two power supplies are in power failure or a cable fails, the non-important load circuit is automatically disconnected due to voltage loss tripping, and the diesel generator supplies power to the important load circuit after self-starting. When the station power supply is recovered, operators are required to arrive at the site to manually close the switches of all the non-important loops. The automation degree is low, the power supply recovery time is long, and the improvement of the operational reliability is not facilitated.

In the power supply system II shown in fig. 2, two segments of buses are normally operated in separate rows, and when one power supply or one power supply fails, the other power supply can bear the entire load; when two power supplies are in power failure or a cable fails, the diesel generator automatically supplies power to important loads on the connected bus. In the wiring mode, important loads and non-important loads need to be hung on two sections of buses respectively, and only the important loads are distributed on the buses connected with the diesel generator. Therefore, a double-loop power supply cannot be provided for important loads, and the reliability is low.

Therefore, how to automatically input and cut off important/non-important loads according to different operation modes of the system, and ensuring the power supply reliability of the loads automatically and intelligently is the key point of optimizing the power utilization design of the station.

Disclosure of Invention

The invention aims to provide a station power system based on four-section bus power supply and a control method thereof, aiming at the defects of the prior art, so that important/non-important loads can be automatically input and cut off according to different operation modes, and the power supply reliability of the loads can be ensured automatically and intelligently.

The invention relates to a station power utilization system based on four-section bus power supply, which adopts the technical scheme that: including first generating line ~ fourth generating line, first transformer, second transformer and stand-by generator, first transformer is connected to first generating line through first inlet wire circuit breaker, second transformer and stand-by generator are connected to the second generating line through second inlet wire circuit breaker, third inlet wire circuit breaker respectively, be connected through first contact circuit breaker between first generating line and the second generating line, be connected through second contact circuit breaker between first generating line and the third generating line, be connected through third contact circuit breaker between second generating line and the fourth generating line, be connected with important load on first generating line and the second generating line respectively, be connected with non-important load on third generating line and the fourth generating line respectively.

Preferably, the standby generator further comprises a voltage relay, the voltage relay is connected between the phase B and the phase N of the second bus where the standby generator is located, and the voltage relay is used for being switched on when the bus is in voltage loss so that the standby generator breaker can be switched on.

Preferably, the backup generator is a diesel generator.

Preferably, the first incoming line breaker, the second incoming line breaker, the third incoming line breaker and the first interconnection breaker are controlled by a BZT device or an ATS device.

Preferably, when the bus is in voltage loss, the second and third contact breakers are both opened.

The invention discloses a control method of a station power system based on four-section bus power supply, which adopts the technical scheme that:

when the first transformer and the second transformer both normally operate, the first incoming line breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the first interconnection breaker and the third interconnection breaker are in an opening state;

when the first transformer is abnormal and the second transformer normally operates, the second incoming line breaker, the first interconnection breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the first incoming line breaker and the third incoming line breaker are in an opening state;

when the first transformer normally operates and the second transformer is abnormal, the first incoming line breaker, the first interconnection breaker, the second interconnection breaker and the third interconnection breaker are in a closing state, and the second incoming line breaker and the third incoming line breaker are in an opening state;

when first transformer and second transformer were all unusual, first interconnection circuit breaker, third incoming line circuit breaker were in the combined floodgate state, and first incoming line circuit breaker, second interconnection circuit breaker, third interconnection circuit breaker are in the separating brake state.

It is comparatively preferred, right when first inlet wire circuit breaker carries out the combined floodgate operation, still need satisfy first interconnection circuit breaker separating brake or second inlet wire circuit breaker and the equal separating brake of third inlet wire circuit breaker, if unsatisfied, then first inlet wire circuit breaker does not close a floodgate.

It is comparatively preferred, right when second inlet wire circuit breaker carries out the combined floodgate operation, still need satisfy the third inlet wire circuit breaker separating brake, and first inlet wire circuit breaker or first contact circuit breaker separating brake, if unsatisfied, then the second inlet wire circuit breaker does not close a floodgate.

Preferably, when the third incoming line breaker is switched on, the first incoming line breaker and the second incoming line breaker are required to be switched off and the bus is in no-voltage state, the second incoming line breaker and the third incoming line breaker are required to be switched off, and if the third incoming line breaker is not required to be switched on, the third incoming line breaker is not switched on.

Preferably, when the first interconnection breaker is switched on, the first connection breaker is still required to be switched off or the second and third inlet breakers are both switched off, and if the first connection breaker is not switched on, the first interconnection breaker is not switched on.

The invention has the beneficial effects that:

1. first transformer is connected to first bus through first inlet wire circuit breaker, second transformer and stand-by generator are respectively through second inlet wire circuit breaker, third inlet wire circuit breaker is connected to the second bus, be connected through first contact circuit breaker between first bus and the second bus, be connected through second contact circuit breaker between first bus and the third bus, be connected through third contact circuit breaker between second bus and the fourth bus, be connected with important load on first bus and the second bus respectively, be connected with non-important load on third bus and the fourth bus respectively. The important load and the non-important load are arranged in a segmented mode, so that the flexibility of cutting and investment is enhanced. Meanwhile, under various operation modes, important loads can be operated in a charged mode, the power supply reliability is improved, the switching is controlled by adopting voltage-loss tripping and electric locking, the fault position does not need to be judged manually, the switch is manually cut off to the cabinet surface, and the operation is more intelligent.

2. The system has the advantages that each incoming line breaker and each interconnection breaker are in a closing state or a breaking state along with the abnormity or the running state of the first transformer and the second transformer, so that important loads can run in a charged mode in various running modes, and the power supply reliability is improved.

3. The first incoming line circuit breaker, the third incoming line circuit breaker and the first interconnection circuit breaker are respectively provided with locking conditions, and the switching-on operation of the circuit breakers can be realized only when the locking conditions are met, so that the device damage caused by the switching-on operation by misoperation can be prevented, and the safety of the system is ensured.

Drawings

FIG. 1 is a schematic diagram of a conventional power supply system;

FIG. 2 is a schematic diagram of another prior art power supply system;

FIG. 3 is a station power utilization system based on four-segment bus power supply;

fig. 4 is a schematic diagram of a closing condition of the breaker QF1 according to the present invention;

fig. 5 is a schematic diagram of a closing condition of the breaker QF2 according to the present invention;

fig. 6 is a schematic diagram of the closing condition of the breaker QF3 according to the present invention;

fig. 7 is a schematic diagram of the closing condition of the breaker QF4 according to the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Example one

Fig. 3 shows a schematic structural diagram of a station power system based on four-segment bus power supply according to a preferred embodiment of the present application (fig. 3 shows a first embodiment of the present application), and for convenience of description, only the parts related to the present embodiment are shown, which are detailed as follows:

the system comprises buses 1B-4B, a transformer TSA1, a transformer TSA2 and a diesel generator Gen. Transformer TSA1 is connected to busbar 1B through circuit breaker QF1, transformer TSA2 and standby generator are connected to busbar 2B through circuit breaker QF2, circuit breaker QF4 respectively, be connected through circuit breaker QF3 between busbar 1B and the busbar 2B, be connected through circuit breaker QF5 between busbar 1B and the busbar 3B, be connected through circuit breaker QF6 between busbar 2B and the busbar 4B, be connected with important load on busbar 1B and the busbar 2B respectively, be connected with non-important load on busbar 3B and the busbar 4B respectively.

Preferably, the standby generator further comprises a voltage relay, the voltage relay is connected between the phase B and the phase N of the second bus where the standby generator is located, and the voltage relay is used for being switched on when the bus is in voltage loss so that the standby generator breaker can be switched on.

Preferably, the breaker QF1, the breaker QF2, the breaker QF4 and the breaker QF3 are all controlled by a BZT device or an ATS device.

Preferably, the circuit breaker QF5 and the circuit breaker QF6 are provided with a voltage loss tripping function, and when the bus is in voltage loss, the circuit breaker QF5 and the circuit breaker QF6 are both opened.

The invention discloses a control method of a station power system based on four-section bus power supply, which adopts the technical scheme that:

when the transformer TSA1 and the transformer TSA2 both normally operate, the breaker QF1, the breaker QF2, the breaker QF5 and the breaker QF6 are in a closing state, and the breaker QF3 and the breaker QF4 are in an opening state;

when the transformer TSA1 is abnormal and the transformer TSA2 normally runs, the breaker QF2, the breaker QF3, the breaker QF5 and the breaker QF6 are in a closing state, and the breaker QF1 and the breaker QF4 are in an opening state;

when the transformer TSA1 normally operates and the transformer TSA2 is abnormal, the breaker QF1, the breaker QF3, the breaker QF5 and the breaker QF6 are in a closing state, and the breaker QF2 and the breaker QF4 are in an opening state;

when the transformer TSA1 and the transformer TSA2 are abnormal, the circuit breakers QF3 and QF4 are in a closing state, and the circuit breakers QF1, QF2, QF5 and QF6 are in an opening state.

Example two

The present embodiment provides an optimal control method, which includes:

the running mode of the system dynamically adjusts the 'on' and 'off' states of each incoming line switch and each interconnection switch according to the normal running and the abnormal running of the station transformer.

Under various working conditions, the states of the incoming line switch and the interconnection switch are shown in table 1, wherein 1 represents 'on', 0 represents 'off', and the state of the incoming line switch corresponds to the charged state of the incoming line power supply.

The important load is powered by 1B or 2B, and the non-important load is powered by 3B or 4B;

under normal operating conditions, TSA1 operates with belts 1B and 3B, and TSA2 operates with belts 2B and 4B;

in the TSA1 abnormal state, the TSA2 operates with 2B, 4B, 1B and 3B;

in the TSA2 abnormal state, the TSA1 operates with 1B, 3B, 2B and 4B;

in both TSA1 and TSA2 abnormal states, the important loads on Gen bands 1B and 2B are running, and the non-important loads on 3B and 4B will not run.

Table 1 operation mode of power utilization system of station in various states

The operations of QF1, QF2, QF3 and QF4 may be done automatically by the backup automatic switching BZT or ATS or manually by a human remote/local site. When the ATS is put in, the ATS automatically operates the on-off of the QF1-QF4 circuit breaker according to the condition of the power supply, and the ATS is put into a station variable power supply or a diesel generator power supply, so that the power supply reliability of the load is ensured. When the ATS is put into a power supply of the diesel generator, the QF5 and the QF6 are provided with voltage loss tripping, and in the process of waiting for diesel starting, the QF5 and the QF6 are automatically disconnected, so that the power supply of important loads is ensured.

As shown in fig. 4 to 7, when the circuit breakers QF1 to QF4 are closed, the closing condition needs to be satisfied, and if the closing condition is not satisfied, the closing operation cannot be performed.

When the breaker QF1 is switched on, the breaker QF3 is required to be switched off or both the breaker QF2 and the breaker QF4 are required to be switched off, and if the breaker QF4 is not required to be switched on, the breaker QF1 is not switched on.

When the breaker QF2 is switched on, the breaker QF4 is required to be switched off, the breaker QF1 or the breaker QF3 is switched off, and if the breaker QF3 is not required to be switched on, the breaker QF2 is not switched on.

When the breaker QF4 is switched on, the equal brake division of the breaker QF1 and the breaker QF2 is required, the bus is in voltage loss, the breaker QF5 and the breaker QF6 are both switched off, and if the breaker QF 3535 4 is not switched on.

When the breaker QF3 is switched on, the breaker QF1 is required to be switched off or both the breaker QF2 and the breaker QF4 are required to be switched off, and if the breaker QF4 is not required to be switched on, the breaker QF3 is not switched on.

The bus voltage loss means that the bus voltage U is less than 30% Un, and the Un is the normal voltage of the bus.

EXAMPLE III

The embodiment provides a design method of the power utilization system, which comprises the following processes:

collecting all low-voltage alternating current power supply loads of the transformer substation, classifying the low-voltage alternating current power supply loads according to importance degrees, distributing the low-voltage alternating current power supply loads to different buses according to the load sizes of the low-voltage alternating current power supply loads, and taking uniform distribution as a principle;

according to wiring requirements, bus-tie breakers are arranged among buses, station transformers and diesel generators are arranged on inlet lines of the bus-tie breakers, protection control logic relations are set among switches, and QF5 and QF6 bus-tie breakers are provided with voltage loss tripping functions.

And configuring a spare power automatic switching device. The automatic bus transfer device collects the power supply voltage of an electric incoming line and the power supply voltage of a diesel generator for 2-way stations and collects the states of QF1-QF4 circuit breakers.

And configuring internal logic of the backup power automatic switching device according to the operation mode.

The main switch, the spare power automatic switching operation state and the alarm signal are connected to the upper-level monitoring system, and the upper-level monitoring system monitors the power supply system.

All alternating current disk cabinets are arranged in the same power distribution room, and the disk cabinets are arranged.

When two sections of important buses are electrified, the interconnection switch does not allow closing operation. The capacity of any station transformer needs to meet the operation requirements of all loads of the transformer substation; the capacity of the diesel generator needs to meet the operation requirement of important loads, and the operation time is determined according to the requirement.

The Angola LAUCA connection line project is located in the northwest part of Angola, belongs to an important node in a core backbone network frame of the country, and provides a very high requirement for the reliability of a project transformer substation for the MINEA of the second-level LAUCA hydropower station of the wide zha river. After the system is put into an angora LAUCA connecting line project, the 400V alternating current system adopts a four-section bus power supply connection mode. At present, the transformer substation is successfully put into operation and stably operates for over 365 days, and the optimized power utilization wiring mode of the transformer substation meets the power supply reliability.

The development and transformation project of the CottDewatt power grid comprises 26 new extension substations with the voltage grades of 90kV and 225 kV. The project is built, the power grid level of the Kotedawak is greatly improved, the national power supply rate of the Kotedawak is improved from 48% to 100%, and the tension situation of power supply is relieved. Therefore, this project directly affects the degree of power development across the country of kortedw, and the energy sector of the proprietor kortedw imposes strict requirements on reliability. After the system is put into development and transformation projects of a Cottodeaw power grid, a 400V alternating current system adopts a four-section bus power supply wiring mode. Currently, 26 substations have all been successfully operated.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.