CN112713586A - Low-voltage intelligent power distribution self-healing and power supply switching control system - Google Patents
Low-voltage intelligent power distribution self-healing and power supply switching control system Download PDFInfo
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- 238000012546 transfer Methods 0.000 claims description 11
- 239000004973 liquid crystal related substance Substances 0.000 claims description 7
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/007—Arrangements for selectively connecting the load or loads to one or several among a plurality of power lines or power sources
- H02J3/0073—Arrangements for selectively connecting the load or loads to one or several among a plurality of power lines or power sources for providing alternative feeding paths between load and source when the main path fails, e.g. transformers, busbars
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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Abstract
The invention discloses a low-voltage intelligent power distribution self-healing and power conversion control system, which comprises a plurality of paths of 0.4KV power supply load lines, an intelligent plastic shell switch and a background control system; each power supply line comprises a transformer, a switch and a demand side electric load; one end of the transformer is connected with a 10KV voltage line, and the other end of the transformer is electrically connected with the demand side electric load through a switch and used for supplying power to the demand side electric load; one end of the intelligent plastic shell switch is connected between a switch of one 0.4KV power supply line and a demand side electric load, and the other end of the intelligent plastic shell switch is connected into a switch of the other 0.4KV power supply line and the demand side electric load; and the intelligent molded case switch is used for acquiring power signals of incoming wires on two sides in real time and sending the power signals to the background control system so as to control the closing of the intelligent molded case switch, and further realize the power supply conversion of the electric load on the demand side in any two paths of 0.4KV power supply lines. The invention can realize automatic power supply conversion.
Description
Technical Field
The invention relates to the technical field of power supply and distribution, in particular to a low-voltage intelligent power distribution self-healing and power supply conversion control system.
Background
At present, with the increase and capacity expansion of users, branch loads are sometimes directly added to the former power distribution room, so that part of power distribution is in a high-load state for a long time; and some power distribution wastes power distribution amount because the power utilization is not expected for a long time or the enterprise users are in a low-load state for a long time due to the emigration. In addition, the public transformer rooms are often distributed in a staggered mode or the main lines are quite close to one another in part, so that part of power supply lines are changed into a closed loop operation mode or a power supply switching mode, the burden of high-load distribution and transformation can be relieved, meanwhile, the reliable power supply of a power distribution network to users can be guaranteed, and resources are fully utilized. Meanwhile, when the power distribution room needs to be overhauled, the power failure time and range can be reduced by transferring loads. However, the distribution network may generate a large impact current at the moment of loop closing to affect the stable operation of the superior power supply, or a large circulation current may be generated in the ring network after the loop closing is stable, which may cause overload of the electrical equipment or the circuit, and even cause tripping of the relay protection device, thereby causing a serious impact on the safe operation of the whole power grid. Therefore, before the loop closing operation, it is necessary to acquire and detect the electrical parameters of the buses at the two ends, such as loop closing impact current, steady-state current, angle difference, load rate difference of power distribution at the two sides, and the like in real time to determine whether the loop closing operation is available, so as to further determine whether the loop closing operation is available. In addition, a low-voltage bus of a distribution room is not allowed to be subjected to loop closing and switching to ensure safe operation of a power grid, so that a method of switching after power failure is adopted during operation of the traditional low-voltage switching, the power failure times and power failure time of a user are increased, and poor experience is brought to the user.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a low-voltage intelligent power distribution self-healing and power conversion and supply control system, which can solve the problems of long power failure times, long power failure time and the like caused by manual power conversion and supply in the prior art.
The purpose of the invention is realized by adopting the following technical scheme:
a low-voltage intelligent power distribution self-healing and power supply conversion control system comprises a plurality of paths of 0.4KV power supply lines, an intelligent plastic shell switch and a background control system; each 0.4KV power supply line comprises a transformer, a switch and a demand side power load; one end of the transformer is connected with a 10KV voltage line, and the other end of the transformer is electrically connected with the demand side electric load through a switch and used for converting the 10KV voltage into 0.4KV voltage and supplying power to the demand side electric load; the intelligent plastic shell switch is connected between any two paths of 0.4KV power supply lines, one end of the intelligent plastic shell switch is connected between a switch of one 0.4KV power supply line of the two paths of 0.4KV power supply lines and a demand side electric load, and the other end of the intelligent plastic shell switch is connected between a switch of the other 0.4KV power supply line of the two paths of 0.4KV power supply lines and the demand side electric load; the intelligent plastic shell switch is in communication connection with the background control system and used for acquiring power signals of incoming wires on two sides in real time and sending the power signals of the incoming wires on the two sides to the background control system, so that the background control system can realize switching-on control of the intelligent plastic shell switch according to switching power supply control logic, and further realize that the power load on the demand side of one 0.4KV power supply line in any two 0.4KV power supply lines is transferred to the transformer of the other 0.4KV power supply line for power supply.
Furthermore, any two paths of 0.4KV power supply lines are marked as a first path of 0.4KV power supply line and a second path of 0.4KV power supply line; the first path of 0.4KV power supply line comprises a first transformer and a first switch, one end of the first transformer is connected to the 10KV voltage line, and the other end of the first transformer supplies power to a first demand side electric load through the first switch; the second 0.4KV power supply line comprises a second transformer and a second switch, one end of the second transformer is connected with the 10KV voltage line, and the other two ends of the second transformer supply power for a second demand side electric load through the second switch; one end of the intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the intelligent plastic shell switch is connected between the second switch and the second demand side electric load; the transfer power control logic comprises: when the first transformer or the first switch has a fault, a closing instruction is sent to the intelligent plastic shell switch through the background control system to control the intelligent plastic shell switch to be closed, so that the first demand side power load is transferred to the second transformer to supply power; when the second transformer or the second switch has a fault, the background control system sends a closing instruction to the intelligent plastic shell switch to control the intelligent plastic shell switch to close, so that the second demand side electric load is transferred to the first transformer to supply power.
Further, the transfer power control logic comprises: when the first transformer is overloaded or the second transformer is overloaded, a closing instruction is sent to the intelligent plastic shell switch through the background control system to control the intelligent plastic shell switch to be closed, so that the first demand side electric load and the second demand side electric load are supplied with power by the first transformer and the second transformer at the same time.
Further, the device also comprises an electric interlocking mechanism and an important load; the intelligent plastic shell switch comprises a first intelligent plastic shell switch and a second intelligent plastic shell switch; one end of the first intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the first intelligent plastic shell switch is electrically connected with the key load; one end of the electric interlocking mechanism is electrically connected with the first intelligent plastic shell switch, and the other end of the electric interlocking mechanism is electrically connected with the second intelligent plastic shell switch; the electric interlocking mechanism is used for detecting the closing state of the first intelligent plastic shell switch and the closing state of the second intelligent plastic shell switch and sending the closing states to the background control system; the first intelligent plastic shell switch is used for acquiring power signals of incoming wires at two sides in real time and sending the power signals to the background control system; the second intelligent plastic shell switch is used for acquiring power signals conducted on two sides in real time and sending the power signals to the background control system; and the background control system is used for realizing the switching-on control of the first intelligent molded case switch and the second intelligent molded case switch by combining the switching-on control logic according to the power supply signals of the two incoming lines sent by the first intelligent molded case switch, the power supply signals of the two incoming lines sent by the second intelligent molded case switch, the switching-on state of the first intelligent molded case switch and the switching-on state of the second intelligent molded case switch, so that the automatic load switching-on control is realized.
Further, under normal conditions, the first intelligent molded case switch and the second intelligent molded case switch are not switched on at the same time.
Further, when the first transformer and/or the first switch are abnormal, the background control system controls the first intelligent plastic shell switch to be switched on and the second intelligent plastic shell switch to be switched on, so that the first demand side power load and the key load are supplied with power by the second transformer; when the second transformer and/or the second switch are abnormal, the background control system controls the first intelligent plastic shell switch to be switched on and the second intelligent plastic shell switch to be switched on, so that the second demand side electric load and the key load are supplied with power by the first transformer.
Furthermore, the intelligent plastic shell switch comprises a box body, a chip, an electric operating mechanism, a voltage acquisition circuit, a current acquisition circuit, a switching value acquisition circuit, a clock circuit, a keyboard and a liquid crystal display screen, wherein the chip, the electric operating mechanism, the voltage acquisition circuit, the current acquisition circuit, the switching value acquisition circuit and the clock circuit are arranged in the box body; the voltage acquisition circuit, the current acquisition circuit, the switching value acquisition circuit, the clock circuit and the electric operating mechanism are respectively electrically connected with the chip, and the clock circuit is used for providing a system time reference; the chip is used for acquiring power signals of incoming wires at two sides through the voltage acquisition circuit, the current acquisition circuit and the switching value acquisition circuit and sending the power signals to the background control module; the liquid crystal display screen is electrically connected with the chip and is used for displaying relevant data of the intelligent plastic shell switch, including time and a closing state; the keyboard is electrically connected with the chip and used for inputting corresponding data to the chip so as to control the switching-on or switching-off of the electric operating mechanism of the intelligent plastic shell switch.
Furthermore, the intelligent plastic shell switch is internally provided with a communication module which is in communication connection with a background control system through the communication module; the background control system is in communication connection with the mobile APP; the mobile APP is used for checking the running state of the intelligent plastic shell switch through the background control system and sending a control instruction to the intelligent plastic shell switch, so that the intelligent plastic shell switch executes corresponding operation.
Furthermore, the intelligent plastic shell switch is provided with an RS485 communication interface and a GPRS communication module which are isolated from each other by photoelectricity; the GPRS communication module, the hardware watchdog and the RS485 communication interface are respectively electrically connected with the chip; the hardware watchdog is used for realizing system reset of the intelligent plastic shell switch; and the GPRS communication module is used for acquiring the position information of the intelligent plastic shell switch, and the RS485 communication interface is used for externally connecting RS485 equipment.
Further, the remote control device also comprises a remote controller; the remote controller is in communication connection with the intelligent plastic shell switch and is used for sending a control instruction to the intelligent plastic shell switch so that the intelligent plastic shell switch can execute corresponding operation.
Compared with the prior art, the invention has the beneficial effects that:
according to the intelligent plastic shell switch, a common switch is replaced by the intelligent plastic shell switch, a power supply signal in each 0.4KV line is automatically collected and sent to the background control system, so that the background control system judges whether the power supply of a demand side power load is abnormal or not according to the power supply signal, and the demand side power load supplied by the intelligent plastic shell switch is switched to other power supplies when one power supply fails through switching on of the intelligent plastic shell switch, so that power supply conversion is realized, the power failure times and power failure time of a user are greatly reduced, the user experience is improved, and meanwhile, the problems that the power supply abnormal condition is judged manually and the operations such as manual switching on are difficult in the prior art are solved.
Drawings
Fig. 1 is a circuit connection diagram of a low-voltage ring network to power supply control system in a low-voltage intelligent power distribution self-healing and power supply control system provided by the invention;
FIG. 2 is a circuit diagram of a transfer control circuit formed by two transformers in the same power distribution room according to the present invention;
FIG. 3 is a circuit diagram of a transfer control circuit formed by two transformers in different power distribution rooms according to the present invention;
FIG. 4 is a circuit diagram of a power transfer control circuit formed by a plurality of transformers according to the present invention;
fig. 5 is a circuit connection diagram of a key load to power supply control system in the low-voltage intelligent power distribution self-healing and power supply control system provided by the invention;
fig. 6 is a block diagram of an intelligent molded case switch provided by the present invention.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
The invention provides a low-voltage intelligent power distribution self-healing and power supply switching control system, which adopts an intelligent switch to replace a traditional load switch so as to realize power supply switching control, automatically performs data acquisition, operation and the like through the intelligent switch, performs power supply switching control according to an operation result, and simultaneously sends the operation result to an operator for checking so as to find a line problem and make adjustment measures in time. According to different application scenes of power supply transfer, the invention comprises two implementation modes: the low-voltage ring network power supply switching control system and the key load power supply switching control system.
The invention provides a first embodiment, a low-voltage ring network power supply conversion control system comprises a plurality of paths of 0.4KV power supply lines, an intelligent plastic shell switch and a background control system. Each 0.4KV power supply line comprises a transformer, a switch and a demand side power load. One end of the transformer is connected with a 10KV high-voltage line, and the other end of the transformer is connected with a demand side electric load through a switch and used for converting the 10KV high voltage into 0.4KV low voltage to supply power to the demand side electric load.
One end of the intelligent plastic shell switch is connected into any two paths of 0.4KV power supply lines. Preferably, one end of the intelligent plastic shell switch is connected between the switch of one 0.4KV power supply line of the two 0.4KV power supply lines and the demand side electric load, and the other end of the intelligent plastic shell switch is connected between the switch of the other 0.4KV power supply line of the two 0.4KV power supply lines and the demand side electric load.
The intelligent plastic shell switch is in communication connection with the background control system, power signals of the incoming lines on the two sides are detected in real time, and the power signals of the incoming lines on the two sides are sent to the background control system, so that the background control system can realize switching-on control of the intelligent plastic shell switch according to a switching-power supply control logic, and further switching-power supply of power loads on demand sides in two paths of 0.4KV power supply lines is realized. That is, when any one of the two 0.4KV power supply lines is abnormal, the intelligent plastic shell switch is switched on, so that the other one of the two 0.4KV power supply lines supplies power to the demand side electrical load of the two power supply lines at the same time.
Preferably, the present embodiment is described by using two power supply lines, as shown in fig. 1, the present embodiment includes a first 0.4KV power supply line, a second 0.4KV power supply line, an intelligent plastic-casing switch, and a background control system.
The first path of 0.4KV power supply line comprises a first transformer, a first switch and a first demand side electric load. The second 0.4KV power supply line comprises a second transformer, a second switch and a second demand side electric load.
One end of the first transformer is connected to a 10KV high-voltage line, and the other end of the first transformer supplies power to a first demand side electric load through a first switch.
Similarly, one end of the second transformer is connected to the 10KV high-voltage line, and the other end of the second transformer supplies power to the second demand-side electrical load through the second switch. The first demand side electrical load and the second demand side electrical load may include one load device or a plurality of load devices.
The first end of the intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the intelligent plastic shell switch is connected between the second switch and the second demand side electric load.
The power supply signals of the incoming lines on the two sides are achieved through the intelligent plastic shell switch and are sent to the background control system, so that the background control system can judge whether power supply in two power supply lines is normal or not according to the power supply signals conducted on the two sides, and then sends a closing instruction to the intelligent plastic shell switch, the first demand side power load or the second demand side power load is switched to a transformer of the other power supply line to supply power, and power switching is achieved. According to the invention, through automatic detection, control and switching-on of the intelligent plastic shell switch, the problems of complex operation such as manual judgment, manual switching-on and the like in the prior art are solved.
Preferably, the built-in communication module of the intelligent molded case switch provided by this embodiment is in communication connection with the background control system through the communication module, so as to realize data interaction with the background control system, for example, the background control system can remotely check the operating state of the intelligent molded case switch through a corresponding APP and send a corresponding control instruction to the intelligent molded case switch, so as to control the intelligent molded case switch to execute a corresponding operation.
For the circuit of fig. 1, when the circuit is normally powered: the 10KV high-voltage circuit generates 0.4KV voltage after transformation through the first transformer, and then supplies power to the first demand side electric load through the first switch.
The 10KV high-voltage line generates 0.4KV voltage after being transformed by the second transformer, and then the second switch supplies power to the second demand side electric load.
When the 10KV high-voltage line or the first transformer fails: at this moment, first demand side power load can't realize normal power supply, consequently, in order to guarantee the normal power supply of first load, through moulding the shell switch with intelligence combined floodgate for under first demand side power load transferred the second transformer, supply power for first demand side power load, second demand side power load simultaneously through the second transformer, also realize transferring the power supply, thereby guarantee the normal work of first demand side power load. Preferably, in this embodiment, the intelligent molded case switch automatically acquires electrical data such as voltage or current of incoming lines on both sides, and sends the data to the background control system, so that the background control system determines that the first switch is under voltage loss, and at this time, the intelligent molded case switch is switched on to transfer the first demand side power load to the second transformer.
Similarly, when the 10KV high-voltage line fails or the second transformer fails: the system obtains the voltage loss of the second switch according to the electrical judgment, and controls the intelligent plastic shell switch to be switched on through the background control system; at the moment, the second demand side electric load is transferred to the first transformer through the intelligent plastic shell switch to supply power.
That is, when the power supply of any one demand side power load is abnormal, the intelligent plastic shell switch can be used for automatically transferring the power supply to the power supply side of another demand side power load for power supply, and the looped network power supply is realized through the intelligent plastic shell switch.
Preferably, as shown in fig. 6, the intelligent molded case switch provided by the present invention includes a case, a chip, a protection outlet relay, a communication module, a voltage acquisition circuit, a current acquisition circuit, a switching value acquisition circuit, a clock circuit, a hardware watchdog, an electric operating mechanism, a liquid crystal display and a keyboard, which are installed in the case.
Wherein, voltage acquisition circuit, current acquisition circuit, switching value acquisition circuit, electric operating mechanism respectively with chip electric connection. The chip is used for detecting power supply information of incoming lines on two sides of the intelligent plastic casing switch through the voltage acquisition circuit, the current acquisition circuit and the switching value acquisition circuit and sending the detected power supply information to the background control system through the communication module, so that the background control system judges the power supply state of the incoming lines on two sides according to the power supply information of the incoming lines on two sides of the intelligent plastic casing switch and judges whether power is supplied or not, and the corresponding control instruction is generated to control the switching-on control of the electric operating mechanism of the intelligent plastic casing switch.
And the clock circuit is used for providing a time reference of the system.
The liquid crystal display is electrically connected with the chip and used for displaying relevant information.
The protection outlet relay is electrically connected with the chip.
The state of the superior power supply state of the intelligent plastic shell switch is judged through the protection outlet relay, so that whether the power supply at two ends of the intelligent plastic shell switch fails or not is judged.
And the hardware watchdog is used for resetting the system and provides guarantee for the safe operation of the system. When the system fails, the system can be reset through the hardware watchdog.
That is, the electric data of both sides inlet wire is obtained through intelligent moulded case switch is automatic, also the electric current or voltage etc. in two way power supply lines detect to the realization judges both sides power supply's state, when certain power supply voltage of a kind breaks down, through closing a floodgate with intelligent moulded case switch's electric operating mechanism, can make the demand side electric load of this way change the realization power supply in another way's power supply line.
Preferably, the intelligent plastic shell switch in the embodiment has a small size and is convenient to install, and all the equipment is installed in one box body, so that the box body can be directly installed at the corresponding position without specially configuring an electric cabinet for the intelligent plastic shell switch. The intelligent plastic shell switch provided by the invention has the characteristics of high safety, high reliability and the like; meanwhile, the intelligent plastic shell switch integrates various functions including fault recording, operation recording, grounding current, current setting, three-phase busbar temperature measurement, intelligent electric meter metering, communication function and the like.
According to the invention, by utilizing the switching function and the intelligent data acquisition function of the intelligent plastic shell switch, the information of ring network power supply can be rapidly judged, so that the operation of circuit power supply is simpler and safer, and compared with the prior art which adopts manual judgment and manual control of switch closing operation, the detection is more timely, the efficiency is higher, and the operation is safer.
Preferably, for the low-voltage power conversion, in order to ensure the operation of the low-voltage power conversion, the embodiment has corresponding requirements on the loads of the two transformers, specifically:
(1) the sum of all the loads supplied by the two transformers should not exceed the rated load of any one of the transformers. For example, when the rated load of any one transformer is smaller than the sum of all loads, and the sum of all loads is supplied by one transformer after power conversion, the rated load of the transformer is exceeded, and overload is caused.
(2) The capacities of the two transformers are kept consistent, the parameters are consistent, and the rated voltage ratio is consistent.
Preferably, the intelligent plastic shell switch provided by the invention also has the functions of automatic input, manual input, automatic reset, loop closing and overcurrent protection. And if yes, automatically switching the loop to supply power, and simultaneously actively reporting corresponding operation information to a master station or a related responsible person.
Preferably, the intelligent plastic shell switch is further provided with a photoelectric isolated RS485 communication interface and has a GPRS wireless communication extension function. Through a wired RS485 communication interface, convenience is provided for power grid operation and maintenance, and specific data support is provided for energy management.
Preferably, the control system further comprises a remote controller, the remote controller is connected with the intelligent plastic casing switch, and the intelligent plastic casing switch executes corresponding operation according to the control instruction by sending a corresponding control instruction to the intelligent plastic casing switch. That is, the intelligent plastic shell switch provided by the invention can receive the local instruction sent by the remote controller and the remote instruction sent by the background control system, so that the corresponding operation is realized, and the functions of local control and remote control are realized. The remote command may include a parameter setting command, a system operating state display and query command, a system diagnosis command, a test command, a self-diagnosis command, a reset command, and the like. More preferably, the intelligent plastic shell switch of the embodiment further has a timing self-checking function, and can timely judge whether the running state of the intelligent plastic shell switch is normal, and when abnormality occurs, abnormal information is recorded and uploaded to a remote background control system.
Similarly, when the power loads of the demand sides of the first transformer and the second transformer are unbalanced, for example, when the power loads of the demand sides of a certain power supply line are overloaded or lightly loaded, the power supply conditions of the two power supply lines can be judged by acquiring power signals carried out on two sides in real time through the intelligent plastic shell switch, and then the looped network is switched to supply power through switching on.
Preferably, as shown in fig. 2, two power supply lines are in one power distribution room, only one end of the intelligent plastic-casing switch needs to be connected between the first demand-side power load and the first switch, the other end of the intelligent plastic-casing switch needs to be connected between the second demand-side power load and the second switch, and then the control logic for switching the ring network to the power supply is set through the system, so that the ring network can be automatically switched to the power supply through the intelligent plastic-casing switch. That is, the invention can realize the power supply of the looped network by simply replacing the existing looped network circuit, thereby greatly reducing the circuit transformation cost.
As shown in fig. 3, two adjacent power distribution rooms are supplied with power by using independent transformers, wherein a No. 1 transformer and a No. 2 transformer transform a 10KV bus into a low-voltage 0.4KV bus for power supply; the K1 and K2 switches are ordinary switches.
Because two transformers are in different distribution rooms respectively, some distances are kept between. Similarly, the invention only needs to arrange an intelligent plastic shell switch in one of the power distribution rooms, and one end of the intelligent plastic shell switch is connected between the first switch and the demand side electric load of the first power distribution room, and the other end of the intelligent plastic shell switch is connected between the second switch and the demand side electric load of the second power distribution room; meanwhile, the intelligent plastic shell switch is arranged on the main line. Therefore, all the demand side electric loads can be supplied with power and controlled to supply power through the intelligent plastic shell switch. That is, the power supply switching implementation of the invention is not limited by the distance of the transformer, and can be implemented even if two transformers are respectively positioned in different power distribution rooms.
As shown in fig. 4, the power supply circuit includes a plurality of power distribution rooms, and each power distribution room has a corresponding transformer for supplying power. Wherein, 1 number becomes (1 transformer) and is in No. 1 and joins in marriage electrical room, 2 numbers become and is in No. 2 and joins in marriage electrical room, and 3 numbers become and be in central distribution electrical room with No. 4, and 5 numbers become and be in No. 3 and join in marriage electrical room, and 6 numbers become and be in No. 4 and join in marriage electrical room. An intelligent plastic shell switch is arranged between any two transformers to realize power conversion and supply
Preferably, because there are a plurality of transformers, the work of transferring power supply is realized by arranging two intelligent plastic shell switches between two transformers in the embodiment, so that the control of transferring power supply is more flexible, and the load of one transformer can be transferred to a specific transformer for power supply. For example, two intelligent plastic shell switches 435B and 435A are arranged between the two transformers of No. 1 and No. 2 to realize the control of power supply. Similarly, two intelligent plastic shell switches 431B and 413A are arranged between the No. 2 transformer and the No. 3 transformer; two intelligent plastic shell switches 424A and 424B are arranged between the No. 4 transformer and the No. 5 transformer; two intelligent plastic shell switches 446A and 446B are arranged between the No. 5 transformer and the No. 6 transformer; two intelligent plastic shell switches 456A and 456B are arranged between the No. 6 transformer and the No. 1 transformer. Since the No. 3 transformer and the No. 4 transformer are in the same power distribution room, the power supply can be realized by arranging the intelligent plastic shell switch 412 between the No. 3 transformer and the No. 4 transformer.
Preferably, for the control system for switching the key load to the power supply, the control system further includes an electrical interlocking mechanism in addition to the multiple 0.4KV power supply lines, the intelligent plastic-casing switches and the background control system, and the intelligent plastic-casing switches include two intelligent plastic-casing switches, which are respectively marked as a first intelligent plastic-casing switch and a second intelligent plastic-casing switch.
More preferably, the important load in this embodiment refers to a device that is important in the power supply circuit, and generally cannot be powered off during the power supply process, and the demand-side power load is a device that is less important than the important load.
Compared with a low-voltage ring network power supply conversion control system, the key load power supply conversion control system in the embodiment needs to be additionally provided with an electric interlocking mechanism to carry out electric interlocking on the two intelligent plastic shell switches. Specifically, as shown in fig. 5, in this embodiment, the first 0.4KV power supply line also includes a first transformer, a first switch, and a first demand-side electrical load, and the second 0.4KV power supply line also includes a second transformer, a second switch, and a second demand-side electrical load.
One end of the first intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the first intelligent plastic shell switch is electrically connected with the key load. One end of the second intelligent plastic shell switch is connected between the second switch and the second demand side electric load, and the other end of the second intelligent plastic shell switch is electrically connected with the key load.
The first path of 0.4KV power supply line or/and the second path of 0.4KV power supply line can supply power to the important load by controlling the switching-on of the first intelligent plastic shell switch or the second intelligent plastic shell switch.
One end of the electric interlocking mechanism is electrically connected with the first intelligent plastic shell switch, and the other end of the electric interlocking mechanism is electrically connected with the second intelligent plastic shell switch, and the electric interlocking mechanism is used for detecting the closing state of the first intelligent plastic shell switch and the closing state of the second intelligent plastic shell switch so as to realize the interlocking of the first intelligent plastic shell switch and the second intelligent plastic shell switch. Preferably, in this embodiment, under normal operation, the first intelligent molded case switch and the second intelligent molded case switch cannot be switched on at the same time, so as to achieve normal power supply.
In addition, the circuit provided by the embodiment can also be operated by loop closing transfer, and when the background system judges that the requirements are met through a series of signals, the automatic loop closing transfer is executed; namely, two transformers supply power for a demand side load and a key load at the same time, at the moment, a first intelligent plastic shell switch and a second intelligent plastic shell switch can be allowed to be switched on at the same time, and the key load is operated in an uninterrupted power-to-power mode; therefore, the electric interlock mechanism in this embodiment is configured to implement an interlock function for the first intelligent molded case switch and the second intelligent molded case switch according to a normal operating state of the circuit.
And the electric interlocking mechanism is in communication connection with the background control system. The first intelligent plastic casing switch and the second intelligent plastic casing switch are respectively in communication connection with the background control system and used for sending power signals of incoming lines on two sides to the background control system in real time, and then the background control system can achieve closing control over an electric operating mechanism of each intelligent plastic casing switch according to the power signals of the incoming lines on two sides of each intelligent plastic casing switch, the closing state of the first intelligent plastic casing switch and the closing state of the second intelligent plastic casing switch.
Specifically, when the first transformer and/or the first switch is abnormal, the first intelligent molded case switch and the second intelligent molded case switch send detected power signals of incoming lines at two sides to the background control system in real time, so that the background control system judges the power signals of the incoming lines at two sides sent by the two intelligent molded case switches and generates a control instruction, and then the first intelligent molded case switch and/or the second intelligent molded case switch are controlled to be switched on, so that the first demand side power load and the key load are supplied with power by the second transformer; when the second transformer and/or the second switch are abnormal, the background control system controls the first intelligent plastic shell switch to be switched on and the second intelligent plastic shell switch to be switched on, so that the second demand side electric load and the key load are supplied with power by the first transformer. Meanwhile, when the switching-on control of the first intelligent plastic shell switch and the second intelligent plastic shell switch is controlled, the switching-on state of the first intelligent plastic shell switch and the switching-on state of the second intelligent plastic shell switch sent by the electric interlocking mechanism are judged.
Namely: under normal conditions, the first transformer may supply power to the first demand side electrical load. The second transformer supplies power to a second demand side electric load, and one of the first transformer and the second transformer also supplies power to a key load. At this time, the first intelligent molded case switch and the second intelligent molded case switch cannot be switched on simultaneously.
Once a certain transformer fails, the switching-on state of the first intelligent plastic shell switch and the second intelligent plastic shell switch and power signals at two sides detected by the first intelligent plastic shell switch and the second plastic shell switch are detected through the electric interlocking mechanism to realize the switching-on and power supply of key loads.
For example, set for first transformer to be the key load power supply, the first intelligence of this moment moulds shell switch-on, and the second intelligence moulds shell switch-off:
when the first transformer fails, the first intelligent plastic shell switch detects that the first transformer is abnormal in power supply, and the electric appliance interlocking mechanism judges that the first intelligent plastic shell switch is switched on and the second intelligent plastic shell switch is switched off, and controls the second intelligent plastic shell switch to be switched on, so that the second transformer can simultaneously supply power for a key load and a second demand side power load; meanwhile, the first intelligent plastic shell switch is switched on, so that the second transformer can supply power for the electric load on the second demand side.
When the second transformer breaks down, when the second intelligent plastic shell switch detects that the power supply of the second transformer is abnormal, the electric interlocking mechanism detects that the first intelligent plastic shell switch is closed and the second intelligent plastic shell switch is opened, and in order to ensure that the power supply of the second demand side power load is normal, the second intelligent plastic shell switch is closed, so that the power supply of the first transformer for the second demand side power load can be realized.
According to the judgment logic, the key load can be always in the power supply environment, and the power supply safety of the key load is ensured.
In addition, when loop closing power supply is carried out, the second intelligent plastic shell switch can be switched on at the moment of t1 through background operation, the first intelligent plastic shell switch can be switched off at the moment of t2, and power can be supplied from the first transformer to the second transformer. That is, when the key load is supplied with power by the first transformer, and when t1 is less than t2, the second intelligent plastic-shell switch is turned on first, and then the first intelligent plastic-shell switch is turned off, so that uninterrupted power supply switching of the key load can be realized, and the guarantee is provided for the safe operation of the key load.
According to the invention, the intelligent plastic shell switch is applied to the power supply device, seamless power supply transfer can be realized, the power failure data and power failure times of users are further reduced, the power supply reliability is improved, and the automatic operation level of the power grid is improved.
More preferably, the intelligent plastic shell switch is adopted to realize power supply, functions of remote switch-on, automatic diagnosis, fault recording, electric parameter calculation, communication and the like can be realized, key load branches in power supply of two transformers or transformer areas are directionally transferred from one transformer to the other transformer, and meanwhile, the intelligent plastic shell switch is safe and reliable and meets the development requirement of miniaturization of power supply of urban residents. The invention can realize the power supply switching function without additional computer control system, background security and other devices, and has the characteristics of simple structure, reliable and safe operation, small maintenance amount, low operation cost and the like.
Preferably, the intelligent molded case circuit breaker integrated in the intelligent molded case switch in the embodiment is a device integrating functions of safety protection, a motor operating mechanism, an intelligent electric energy meter, a wired or wireless communication technology and the like, and can be in direct contact with and control the switching-on and switching-off of the intelligent molded case switch remotely and locally, so that remote and local control is realized, and great convenience is brought to users.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (10)
1. A low-voltage intelligent power distribution self-healing and power supply conversion control system is characterized by comprising a plurality of paths of 0.4KV power supply lines, an intelligent plastic shell switch and a background control system; each 0.4KV power supply line comprises a transformer, a switch and a demand side power load; one end of the transformer is connected with a 10KV voltage line, and the other end of the transformer is electrically connected with the demand side electric load through a switch and used for converting the 10KV voltage into 0.4KV voltage and supplying power to the demand side electric load; the intelligent plastic shell switch is connected between any two paths of 0.4KV power supply lines, one end of the intelligent plastic shell switch is connected between a switch of one 0.4KV power supply line of the two paths of 0.4KV power supply lines and a demand side electric load, and the other end of the intelligent plastic shell switch is connected between a switch of the other 0.4KV power supply line of the two paths of 0.4KV power supply lines and the demand side electric load; the intelligent plastic shell switch is in communication connection with the background control system and used for acquiring power signals of incoming wires on two sides in real time and sending the power signals of the incoming wires on the two sides to the background control system, so that the background control system can realize switching-on control of the intelligent plastic shell switch according to switching power supply control logic, and further realize that the power load on the demand side of one 0.4KV power supply line in any two 0.4KV power supply lines is transferred to the transformer of the other 0.4KV power supply line for power supply.
2. The system according to claim 1, wherein any two 0.4KV power supply lines are marked as a first 0.4KV power supply line and a second 0.4KV power supply line; the first path of 0.4KV power supply line comprises a first transformer and a first switch, one end of the first transformer is connected to the 10KV voltage line, and the other end of the first transformer supplies power to a first demand side electric load through the first switch; the second 0.4KV power supply line comprises a second transformer and a second switch, one end of the second transformer is connected with the 10KV voltage line, and the other two ends of the second transformer supply power for a second demand side electric load through the second switch; one end of the intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the intelligent plastic shell switch is connected between the second switch and the second demand side electric load; the transfer power control logic comprises: when the first transformer or the first switch has a fault, a closing instruction is sent to the intelligent plastic shell switch through the background control system to control the intelligent plastic shell switch to be closed, so that the first demand side power load is transferred to the second transformer to supply power; when the second transformer or the second switch has a fault, the background control system sends a closing instruction to the intelligent plastic shell switch to control the intelligent plastic shell switch to close, so that the second demand side electric load is transferred to the first transformer to supply power.
3. A low-voltage intelligent power distribution self-healing and power supply switching control system according to claim 2, wherein the power supply switching control logic comprises: when the first transformer is overloaded or the second transformer is overloaded, a closing instruction is sent to the intelligent plastic shell switch through the background control system to control the intelligent plastic shell switch to be closed, so that the first demand side electric load and the second demand side electric load are supplied with power by the first transformer and the second transformer at the same time.
4. A low-voltage intelligent power distribution self-healing and power supply conversion control system according to claim 2, further comprising an electrical interlocking mechanism and a heavy load; the intelligent plastic shell switch comprises a first intelligent plastic shell switch and a second intelligent plastic shell switch; one end of the first intelligent plastic shell switch is connected between the first switch and the first demand side electric load, and the other end of the first intelligent plastic shell switch is electrically connected with the key load; one end of the electric interlocking mechanism is electrically connected with the first intelligent plastic shell switch, and the other end of the electric interlocking mechanism is electrically connected with the second intelligent plastic shell switch; the electric interlocking mechanism is used for detecting the closing state of the first intelligent plastic shell switch and the closing state of the second intelligent plastic shell switch and sending the closing states to the background control system; the first intelligent plastic shell switch is used for acquiring power signals of incoming wires at two sides in real time and sending the power signals to the background control system; the second intelligent plastic shell switch is used for acquiring power signals conducted on two sides in real time and sending the power signals to the background control system; and the background control system is used for realizing the switching-on control of the first intelligent molded case switch and the second intelligent molded case switch by combining the switching-on control logic according to the power supply signals of the two incoming lines sent by the first intelligent molded case switch, the power supply signals of the two incoming lines sent by the second intelligent molded case switch, the switching-on state of the first intelligent molded case switch and the switching-on state of the second intelligent molded case switch, so that the automatic load switching-on control is realized.
5. The system according to claim 4, wherein the first intelligent molded case switch and the second intelligent molded case switch are not switched on at the same time under normal conditions.
6. The low-voltage intelligent power distribution self-healing and power supply switching control system according to claim 4, wherein when the first transformer and/or the first switch is abnormal, the background control system controls the first intelligent molded case switch to be switched on and the second intelligent molded case switch to be switched on, so that the first demand side electric load and the key load are supplied with power by the second transformer; when the second transformer and/or the second switch are abnormal, the background control system controls the first intelligent plastic shell switch to be switched on and the second intelligent plastic shell switch to be switched on, so that the second demand side electric load and the key load are supplied with power by the first transformer.
7. The system according to claim 1, wherein the intelligent molded case switch comprises a case, a chip, an electric operating mechanism, a voltage acquisition circuit, a current acquisition circuit, a switching value acquisition circuit, a clock circuit, a keyboard, and a liquid crystal display screen, wherein the chip, the electric operating mechanism, the voltage acquisition circuit, the current acquisition circuit, the switching value acquisition circuit, the clock circuit, the keyboard, and the liquid crystal display screen are mounted outside the case; the voltage acquisition circuit, the current acquisition circuit, the switching value acquisition circuit, the clock circuit and the electric operating mechanism are respectively electrically connected with the chip, and the clock circuit is used for providing a system time reference; the chip is used for acquiring power signals of incoming wires at two sides through the voltage acquisition circuit, the current acquisition circuit and the switching value acquisition circuit and sending the power signals to the background control module; the liquid crystal display screen is electrically connected with the chip and is used for displaying relevant data of the intelligent plastic shell switch, including time and a closing state; the keyboard is electrically connected with the chip and used for inputting corresponding data to the chip so as to control the switching-on or switching-off of the electric operating mechanism of the intelligent plastic shell switch.
8. The low-voltage intelligent power distribution self-healing and power supply conversion control system according to claim 7, wherein the intelligent molded case switch is internally provided with a communication module and is in communication connection with a background control system through the communication module; the background control system is in communication connection with the mobile APP; the mobile APP is used for checking the running state of the intelligent plastic shell switch through the background control system and sending a control instruction to the intelligent plastic shell switch, so that the intelligent plastic shell switch executes corresponding operation.
9. A low-voltage intelligent power distribution self-healing and power supply conversion control system according to claim 7, wherein the intelligent molded case switch is provided with a photoelectrically isolated RS485 communication interface and a GPRS communication module; the GPRS communication module, the hardware watchdog and the RS485 communication interface are respectively electrically connected with the chip; the hardware watchdog is used for realizing system reset of the intelligent plastic shell switch; and the GPRS communication module is used for acquiring the position information of the intelligent plastic shell switch, and the RS485 communication interface is used for externally connecting RS485 equipment.
10. A low-voltage intelligent power distribution self-healing and power conversion control system according to claim 1, further comprising a remote controller; the remote controller is in communication connection with the intelligent plastic shell switch and is used for sending a control instruction to the intelligent plastic shell switch so that the intelligent plastic shell switch can execute corresponding operation.
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