Reverse power transmission prevention device and operation method thereof

Abstract

The invention provides reverse power transmission prevention devices and an operation method thereof. The reverse power transmission prevention devices are arranged on the two sides of a circuit breaker in a low-voltage power distribution cabinet. The reverse power transmission prevention device comprises an electric quantity transmitter, a PLC control unit and an execution unit. The two electric quantity transmitters are arranged on the two sides of the circuit breaker respectively and used for collecting the voltage phase and the active power and transmitting the voltage phase and the active power to the PLC control unit. The PLC control unit is connected with the two electric quantity transmitters and is used for receiving voltage phases transmitted by the two electric quantity transmitters, judging whether a reverse power transmission phase sequence error condition exists or not and sending a control signal and / or an alarm signal; and the execution unit is connected with the PLC control unit and the circuit breaker, and is used for receiving the control signal sent by the PLC control unit and controlling the circuit breaker to trip. According to the invention, the damage of reverse power transmission in a power grid to power equipment and electrical loads in a power supply system can be solved, and stable power utilization of users and safe operation of a power supply network are ensured.

Description

Technical Field

[0001] The present invention relates to the field of reverse power transmission risk prevention, and in particular to a reverse power transmission prevention device and an operating method thereof. Background Art

[0002] In industrial and mining enterprises and residential electricity consumption, due to the variables and wiring methods on the user side, the power supply and consumption in the low-voltage distribution network is complex and uncertain. Power distribution is very likely to produce reverse power transmission, which seriously threatens the safety of the distribution network and is very likely to cause safety accidents.

[0003] With the increasing development of national economy and technology, the daily electricity load demand is increasing. The development and use of low-voltage distribution cabinets not only ensures the safety of daily electricity use, but also improves the flexibility and convenience of electricity terminals. However, the problem of reverse power transmission often occurs in the transmission of low-voltage distribution networks, which seriously restricts the stable demand for daily power distribution.

[0004] According to the power source that may cause reverse power transmission at the user end, there are generally two situations. Some factories and enterprises build their own power plants; the other situation is that ordinary power users, such as household electricity users and shopping mall electricity users, often use self-provided generators or multi-circuit electricity to make up for the poor reliability of single-circuit power supply and improve power reliability. Nowadays, as people's living standards gradually improve, the need for uninterrupted power supply is getting higher and higher, and the above-mentioned power use methods are increasing. Most small and medium-sized users use manual switching of multi-circuit power supplies to save costs. At the same time, most users lack professional technical knowledge and often have reverse power transmission. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide an anti-reverse power transmission device and an operating method thereof to solve the damage caused by reverse power transmission in the power grid to the power equipment and power loads in the power supply system, thereby ensuring the stability of user power consumption and the safe operation of the power supply network.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] An embodiment of the present invention provides an anti-reverse power transmission device, which is arranged on both sides of a circuit breaker in a low-voltage power distribution cabinet; the anti-reverse power transmission device includes: an electric quantity transmitter, a PLC control unit and an execution unit; two electric quantity transmitters are provided, and are respectively installed on both sides of the circuit breaker, for collecting voltage phase and active power, and transmitting them to the PLC control unit; the PLC control unit is connected to the two electric quantity transmitters, for receiving the voltage phase transmitted by the two electric quantity transmitters, judging whether there is a reverse power transmission phase sequence error, and sending a control signal and / or an alarm signal; the execution unit is connected to the PLC control unit and to the circuit breaker, for receiving the control signal sent by the PLC control unit, and controlling the circuit breaker to trip.

[0008] In some embodiments, the PLC control unit is also used to receive the voltage phase transmitted by two power transmitters, and when the phases are the same, determine the forward and reverse directions of the bidirectional power transmitted by the two power transmitters, and send a control signal and / or an alarm signal.

[0009] In some embodiments, the anti-reverse power transmission device is also arranged on any one of the distribution equipment at the intersection of the distribution lines, on the electric poles, and on the pole switches.

[0010] An operating method of an anti-reverse power transmission device, using the anti-reverse power transmission device as described above, comprises the following steps:

[0011] The power transmitter collects voltage phase and active power and transmits them to the PLC control unit;

[0012] The PLC control unit receives the voltage phase transmitted by the two electrical quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal;

[0013] The execution unit receives the control signal sent by the PLC control unit and controls the circuit breaker to trip.

[0014] In some embodiments, the PLC control unit receives the voltage phases transmitted by the two electric quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal, further comprising:

[0015] If the PLC control unit determines that there is a reverse power transmission phase sequence error, it sends a control signal to the execution unit and sends an alarm signal to the host computer at the same time.

[0016] In some embodiments, the PLC control unit receives the voltage phases transmitted by the two electric quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal, further comprising:

[0017] The PLC control unit also receives the voltage phases transmitted by the two electrical quantity transmitters, and when the phases are the same, determines the positive and negative directions of the bidirectional electrical quantity transmitted by the two electrical quantity transmitters, and sends a control signal and / or an alarm signal.

[0018] In some embodiments, the PLC control unit further receives the voltage phases transmitted by the two power transmitters, and when the phases are the same, determines the positive and negative directions of the bidirectional power transmitted by the two power transmitters, and sends a control signal and / or an alarm signal, further comprising:

[0019] If it is determined that the directions of the bidirectional electric quantities transmitted by the two electric quantity transmitters are opposite, a control signal is sent to the execution unit, and an alarm signal is sent to the host computer at the same time.

[0020] In industrial and mining enterprises and residential electricity consumption, due to the variables and wiring methods on the user side, the power supply and consumption in the low-voltage distribution network is complex and uncertain. Power distribution is very likely to produce reverse power transmission, which seriously threatens the safety of the distribution network and is very likely to cause safety accidents.

[0021] With the increasing development of national economy and technology, the daily electricity load demand is increasing. The development and use of low-voltage distribution cabinets not only ensures the safety of daily electricity use, but also improves the flexibility and convenience of electricity terminals. However, the problem of reverse power transmission often occurs in the transmission of low-voltage distribution networks, which seriously restricts the stable demand for daily power distribution.

[0022] According to the power source that may cause reverse power transmission at the user end, there are generally two situations. Some factories and enterprises build their own power plants; the other situation is that ordinary power users, such as household electricity users and shopping mall electricity users, often use self-provided generators or multi-circuit electricity to make up for the poor reliability of single-circuit power supply and improve power reliability. Nowadays, as people's living standards gradually improve, the need for uninterrupted power supply is getting higher and higher, and the above-mentioned power use methods are increasing. Most small and medium-sized users use manual switching of multi-circuit power supplies to save costs. At the same time, most users lack professional technical knowledge and often have reverse power transmission.

[0023] Low-voltage distribution cabinet structure: Power load management control terminal, electric energy meter, monitoring instrument, protection switch, relay, communication enhancement instrument and other equipment constitute the low-voltage power distribution cabinet. Each equipment and instrument cooperates with each other to jointly maintain power supply safety. The low-voltage distribution cabinet is equipped with combined electrical components of various functions, which have the functions of monitoring, transmission, supervision and management of the power grid.

[0024] Automatic protection function of low-voltage distribution cabinet: The low-voltage distribution cabinet is equipped with fuses, circuit breakers and automatic trip switches. Once there are accidents such as short circuit, open circuit, open flame, etc., the instrument with automatic protection function will respond immediately and trip and disconnect the circuit. At the same time, according to the analysis of detection data, the power load is reasonably distributed to improve the stability and safety of power equipment operation. In view of the problem that most areas use overhead lines to transmit electricity, and the lightning protection measures and grounding links are relatively weak, the use of low-voltage distribution cabinets can make up for the defects in the power grid, improve the lightning protection safety of the power grid, automatically protect electrical equipment, and reduce the damage to the power grid caused by thunderstorms.

[0025] Data detection and real-time monitoring function of low-voltage distribution cabinet: Low-voltage distribution cabinet is equipped with various detection elements, such as temperature sensor, voltage sensor, current sensor, etc. Under the control of intelligent control system, data detection and information collection are carried out on the transformer in the distribution cabinet. The real-time information collected is mainly the voltage, current, electric power, etc. of the electrical equipment, which are analyzed and processed by the control end. The monitoring equipment monitors the operation of the facilities in the distribution cabinet in real time. The background is connected to the display, which can observe the operating status of the electrical equipment in the distribution cabinet. Once the data information is abnormal, the early warning and automatic protection functions are immediately activated, so as to realize the safe transmission of electricity to the power grid and ensure the stability of electricity consumption.

[0026] Intelligent reactive power compensation function of low-voltage distribution cabinet: In general, the power loss on the low-voltage side of the transformer is relatively serious. In order to reduce power loss, an intelligent reactive power compensation system is set in the low-voltage distribution cabinet. The system can achieve multi-level compensation to ensure the power balance of power grid equipment and the safe and reliable operation of the system. It can also improve the power factor of the transformer in the distribution network, thereby ensuring the quality and efficiency of power supply. In order to reduce the power loss in the power grid and further eliminate the surge phenomenon, a low-voltage intelligent switch is also added to perform zero switching with the cooperation of the filter, thereby achieving the stability requirements of the power supply of the entire low-voltage power grid system.

[0027] Remote meter reading function of low-voltage distribution cabinet: In order to reduce the intensity of manual labor and improve work efficiency, an intelligent remote energy collection meter is installed at the power consumption terminal of the low-voltage distribution cabinet. The remote energy collection meter can automatically read the power consumption. The use of remote energy meter reading has greatly improved the accuracy of meter reading and laid a favorable foundation for the rapid settlement of power companies.

[0028] Although the low-voltage distribution network uses a technologically advanced multifunctional distribution cabinet, reverse power transmission often occurs on the user side during the power distribution in the low-voltage distribution network. In order to solve this problem, the present invention proposes an anti-reverse power transmission device and an operating method thereof.

[0029] An anti-reverse power transmission device and an operating method thereof are provided in an embodiment of the present invention. The PLC control unit determines whether there is a reverse power transmission phase sequence error by monitoring the phases of the detection points of two electrical quantity transmitters. If a reverse power transmission phase error is found, the execution unit is immediately commanded to control the circuit breaker to trip, and an alarm signal is output to the upper computer so that the staff can arrive at the scene in time to find and solve the problem.

[0030] An anti-reverse power transmission device and its operation method provided in the embodiment of the present invention can judge whether the power supply and distribution is in an abnormal state through a PLC control unit. The PLC control unit judges whether there is a reverse power transmission phase sequence error in the power system based on the voltage, phase, and power relationship on both sides of the circuit breaker, and determines the power supply transmission direction. If there is a reverse power transmission phase sequence error, the anti-reverse power transmission device starts immediately to prevent this phenomenon from continuing, prevent the power grid from reverse power transmission, and restore normal power supply under the control of the power control system, ensuring the safe and normal operation of power supply and distribution in the low-voltage distribution network, improving the stability of power supply of the power grid, strengthening the user-side equipment management and regulating line connections, and ensuring the stability of power consumption. The application of low-voltage distribution cabinets and anti-reverse power transmission devices can reduce the harm of reverse power transmission to the power grid, reduce the failure rate of the power grid, and improve the quality of power supply.

[0031] A reverse power transmission prevention device and an operating method thereof are provided in an embodiment of the present invention. Since the low-voltage distribution network involves a huge number of user types and the line connections in the power grid are complex, problems are often caused by the line connections. The reverse power transmission prevention device, in cooperation with the low-voltage distribution cabinet, strengthens the line connections in the power grid, reasonably allocates the current distribution direction, and avoids affecting the main lines of the power grid during the power distribution process.

[0032] An anti-reverse power transmission device and an operating method thereof are provided in the embodiments of the present invention. The self-provided small-scale power generation equipment and multi-circuit power consumption on the user side are most likely to cause reverse power transmission in the low-voltage distribution network. The use of the anti-reverse power transmission device can strictly control the components and equipment in the line to prevent reverse power transmission caused spontaneously by the user side. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the products involved in the embodiments of the present disclosure, the actual process of the method, etc.

[0034] Figure 1 A schematic diagram of the working principle of an anti-reverse power transmission device in some embodiments of the present disclosure;

[0035] Figure 2 The present invention is a processing flow chart of a PLC control unit of an anti-reverse power transmission device in some embodiments of the present disclosure. DETAILED DESCRIPTION

[0036] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0037] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as an open, inclusive meaning, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics described may be included in any one or more embodiments or examples in any appropriate manner.

[0038] The embodiment of the present invention provides an anti-reverse power transmission device and an operation method thereof, such as Figure 1 As shown, the anti-reverse power transmission device is arranged on both sides of the circuit breaker in the low-voltage distribution cabinet, so as to detect various parameters on both sides of the circuit breaker.

[0039] In some embodiments, the anti-reverse power transmission device includes: a power transmitter, a PLC control unit and an execution unit.

[0040] In some embodiments, two power transmitters are provided and are respectively installed on both sides of the circuit breaker for collecting voltage phase and active power and transmitting them to the PLC control unit.

[0041] The power transmitter is an intelligent instrument used to measure the comprehensive parameters of AC power. It can simultaneously measure the voltage, current, active power, reactive power, apparent power, power factor, frequency, phase and other parameters of each phase of a single-phase or three-phase AC circuit.

[0042] In some embodiments, the PLC control unit is connected to two power transmitters to receive the voltage phase transmitted by the two power transmitters, determine whether there is a reverse power phase sequence error, and send a control signal and / or an alarm signal.

[0043] The control signal sent by the PLC control unit is sent to the execution unit, and the alarm signal sent is sent to the host computer.

[0044] In some embodiments, the execution unit is connected to the PLC control unit and to the circuit breaker, and is used to receive a control signal sent by the PLC control unit and control the circuit breaker to trip.

[0045] The execution unit is electrically or mechanically connected to the circuit breaker. When the execution unit receives the control signal sent by the PLC control unit, it triggers the circuit breaker to trip, thereby protecting the power grid and the safe use of electricity by operators and users, and avoiding the burning of electrical equipment or endangering the safety of personnel.

[0046] An anti-reverse power transmission device and an operating method thereof are provided in an embodiment of the present invention. The PLC control unit determines whether there is a reverse power transmission phase sequence error by monitoring the phases of the detection points of two electrical quantity transmitters. If a reverse power transmission phase error is found, the execution unit is immediately commanded to control the circuit breaker to trip, and an alarm signal is output to the upper computer so that the staff can arrive at the scene in time to find and solve the problem.

[0047] In some embodiments, the PLC control unit is also used to receive the voltage phase transmitted by the two power transmitters. When the phases are the same, it determines the forward and reverse directions of the bidirectional power transmitted by the two power transmitters and sends a control signal and / or an alarm signal.

[0048] The PLC control unit monitors the bidirectional power direction of the detection points of the two power transmitters to determine the positive and negative directions of the bidirectional power direction. If the bidirectional power direction is found to be reverse, it immediately commands the execution unit to control the circuit breaker to trip and outputs an alarm signal to the upper computer so that the staff can arrive at the scene in time to find and solve the problem.

[0049] Exemplarily, the power supply on the power supply side of the substation is selected as the forward power direction. When it is monitored that the electric power transmitted from the user side to the power supply side in the distribution network is reverse, it is determined that the distribution line has reverse power transmission.

[0050] In some embodiments, the anti-reverse power transmission device is also arranged on any one of the distribution equipment at the intersection of the distribution lines, on the electric poles, and on the pole switches.

[0051] In order to determine whether there is reverse power transmission in the low-voltage distribution line, power transmitters can be installed on the distribution equipment at the junction of the distribution lines, on the poles, and on the switches on the poles to collect parameters such as voltage, current, phase, power, and power.

[0052] The present invention also provides an operation method of an anti-reverse power transmission device, using the anti-reverse power transmission device as described above, such as Figure 2 As shown, the process includes steps S100-S300.

[0053] S100, the power transmitter collects the voltage phase and active power and transmits them to the PLC control unit.

[0054] S200, the PLC control unit receives the voltage phase transmitted by the two electrical quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal.

[0055] S300, the execution unit receives the control signal sent by the PLC control unit and controls the circuit breaker to trip.

[0056] In some embodiments, step S200 also includes: S201.

[0057] S201, such as Figure 2 As shown, if the PLC control unit determines that there is a reverse power phase sequence error, it sends a control signal to the execution unit and sends an alarm signal to the host computer at the same time.

[0058] Send a control signal to the execution unit to make the execution unit control the circuit breaker to trip, and send an alarm signal to the host computer to notify the staff.

[0059] In some embodiments, step S200 also includes: S210.

[0060] S210, the PLC control unit also receives the voltage phases transmitted by the two power transmitters, and when the phases are the same, determines the positive and negative directions of the bidirectional power transmitted by the two power transmitters, and sends a control signal and / or an alarm signal.

[0061] In some examples, step S210 also includes: S211.

[0062] S211, if it is determined that the directions of the bidirectional electric quantities transmitted by the two electric quantity transmitters are opposite, a control signal is sent to the execution unit, and an alarm signal is sent to the host computer at the same time.

[0063] The beneficial effects that can be achieved by the operating method of the anti-reverse power transmission device provided in some embodiments of the present invention are the same as the beneficial effects that can be achieved by the anti-reverse power transmission device provided in some of the above embodiments, and will not be repeated here.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in the field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A device for preventing reverse power transmission, characterized in that: The anti-reverse power transmission device is arranged on both sides of the circuit breaker in the low-voltage power distribution cabinet; The anti-reverse power transmission device includes: an electric quantity transmitter, a PLC control unit and an execution unit; The electric quantity transmitter is provided with two and is respectively mounted on both sides of the circuit breaker, and is used to collect voltage phase and active power, and transmit them to the PLC control unit; The PLC control unit is connected to the two electrical quantity transmitters, and is used to receive the voltage phase transmitted by the two electrical quantity transmitters, determine whether there is a reverse power transmission phase sequence error, and send a control signal and / or an alarm signal; The execution unit is connected to the PLC control unit and to the circuit breaker, and is used for receiving a control signal sent by the PLC control unit and controlling the circuit breaker to trip.

2. The anti-reverse power transmission device according to claim 1, characterized in that: The PLC control unit is also used to receive the voltage phases transmitted by the two power transmitters, and when the phases are the same, determine the positive and negative directions of the bidirectional power transmitted by the two power transmitters, and send a control signal and / or an alarm signal.

3. The anti-reverse power transmission device according to claim 1, characterized in that: The anti-reverse power transmission device is also arranged on any one of the power distribution equipment at the junction of the power distribution lines, on the electric pole, and on the pole switch.

4. A method for operating an anti-reverse power transmission device, characterized in that: The anti-reverse power transmission device according to any one of claims 1 to 3 comprises the following steps: The power transmitter collects voltage phase and active power and transmits them to the PLC control unit; The PLC control unit receives the voltage phase transmitted by the two electrical quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal; The execution unit receives the control signal sent by the PLC control unit and controls the circuit breaker to trip.

5. The method for operating the anti-reverse power transmission device according to claim 4, characterized in that: The PLC control unit receives the voltage phases transmitted by the two electric quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal, and further includes: If the PLC control unit determines that there is a reverse power transmission phase sequence error, it sends a control signal to the execution unit and sends an alarm signal to the host computer at the same time.

6. The method for operating the anti-reverse power transmission device according to claim 4, characterized in that: The PLC control unit receives the voltage phases transmitted by the two electric quantity transmitters, determines whether there is a reverse power transmission phase sequence error, and sends a control signal and / or an alarm signal, and further includes: The PLC control unit also receives the voltage phases transmitted by the two electrical quantity transmitters, and when the phases are the same, determines the positive and negative directions of the bidirectional electrical quantity transmitted by the two electrical quantity transmitters, and sends a control signal and / or an alarm signal.

7. The method for operating the anti-reverse power transmission device according to claim 6, characterized in that: The PLC control unit also receives the voltage phases transmitted by the two power transmitters, and when the phases are the same, determines the positive and reverse directions of the bidirectional power transmitted by the two power transmitters, and sends a control signal and / or an alarm signal, further comprising: If it is determined that the directions of the bidirectional electric quantities transmitted by the two electric quantity transmitters are opposite, a control signal is sent to the execution unit, and an alarm signal is sent to the host computer at the same time.

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