Power supply monitoring system

Abstract

The embodiment of the invention discloses a power supply monitoring system. The system comprises a data acquisition board which comprises a power supply bus and a plurality of power supply branch feeder lines electrically connected with the power supply bus; an electromagnetic air switch, an onboard leakage current sensor, a first onboard current sensor and a voltage detection circuit are arranged on each power supply branch feeder; the data acquisition board is also provided with a second onboard current sensor, an alternating current intrusion detection circuit and a resistor control circuit which are all electrically connected with the power supply bus; in the same monitoring unit, the processor is electrically connected with the signal conditioning circuit, the signal conditioning circuit obtains power supply data and transmits the power supply data to the processor, and the processor controls the on-off state of the electromagnetic air switch according to the power supply data. And high integration and high intelligence of the DC feeder screen are realized.

Description

Technical Field

[0001] The invention relates to the technical field of direct current panel power supply, and in particular to a power supply monitoring system. Background Art

[0002] The DC panel is an important part of the power system in power plants and substations, and its stability and reliability are directly related to the normal operation of the power system. The DC feeder panel, as the DC output of the DC panel, mainly supplies power to DC equipment, circuit breakers, emergency lighting and other devices in the station. At present, the DC feeder panel has multi-branch DC output, and the number of branches is usually within 60, and in a few cases it will exceed 60. The DC output of each branch is monitored by multiple independent modules of different types, such as using the branch power detection module to detect the branch on and off, using the insulation resistance detection module to detect the insulation resistance, and using the current detection module to detect the current in the line. The structure is relatively messy and the modules are connected by leads, which is easy to cause wrong wiring and inconvenience for overall debugging. In addition, the DC feeder panels on the market currently have low integration and low intelligence. Summary of the invention

[0003] The present invention provides a power supply monitoring system, which realizes high integration and high intelligence of a DC feeder panel.

[0004] According to one aspect of the present invention, there is provided a power supply monitoring system, comprising:

[0005] At least one monitoring unit, each monitoring unit includes a data acquisition board and a data processing board;

[0006] The data acquisition board includes a power supply bus and a plurality of power supply branch feeders electrically connected to the power supply bus; each power supply branch feeder is provided with an electromagnetic air switch, an onboard leakage current sensor, a first onboard current sensor and a voltage detection circuit;

[0007] The onboard leakage current sensor is used to detect branch leakage current on the power supply branch feeder;

[0008] The first onboard current sensor is used to detect the branch current on the power supply branch feeder;

[0009] The voltage detection circuit is used to detect the branch voltage of the power supply branch;

[0010] The data acquisition board is also provided with a second onboard current sensor, an AC inrush detection circuit and a resistor control circuit, and the second onboard current sensor, the AC inrush detection circuit and the resistor control circuit are all electrically connected to the power supply bus;

[0011] The second onboard current sensor is used to detect the bus current on the power supply bus;

[0012] The AC inrush detection circuit is used to detect the AC inrush on the power supply bus, the bus voltage value of the bus and the bus voltage value to the ground;

[0013] The resistor control circuit is used to control the resistance value between the busbar and the ground;

[0014] The data processing board is provided with a processor and a signal conditioning circuit;

[0015] In the same monitoring unit:

[0016] The processor is electrically connected to the signal conditioning circuit, and the signal conditioning circuit is electrically connected to the electromagnetic air switch, the onboard leakage current sensor, the first onboard current sensor, the voltage detection circuit, the second onboard current sensor, the AC inrush detection circuit and the resistor control circuit on the data acquisition board respectively;

[0017] The signal conditioning circuit is used to obtain branch leakage current, branch current, branch voltage, bus current, AC current injected into the power supply bus, bus voltage value, voltage value to ground and resistance value, and transmit the branch leakage current, branch current, branch voltage, bus current, AC current injected into the power supply bus, bus voltage value, voltage value to ground and resistance value to the processor;

[0018] The processor is used to control the switching state of the electromagnetic air switch according to the branch leakage current, branch current, branch voltage, bus current, AC power entering the power supply bus, bus voltage value, ground voltage value and resistance value.

[0019] Optionally, the processor is used to calculate the branch insulation resistance value of each branch, the branch power of each branch, the bus power and the bus insulation resistance value based on the branch leakage current, branch current, branch voltage, bus current, bus voltage value, voltage to ground and resistance value, and control the switching state of the electromagnetic air switch based on the branch insulation resistance value, branch power, branch current, bus power, bus insulation resistance value and the alternating current entering the power supply bus.

[0020] Optionally, the processor is used to:

[0021] When the branch insulation resistance exceeds the first set resistance value, the electromagnetic air switch on the feeder line of the power supply branch is controlled to be disconnected;

[0022] When the insulation resistance value of the busbar exceeds the second set resistance value, or when AC power is introduced into the power supply busbar, the electromagnetic air switches on all power supply branch feeders connected to the busbar are controlled to be disconnected;

[0023] When the branch power or bus power exceeds the set power value, an alarm is issued.

[0024] Optionally, the processor is used to compare each branch current with the current waveforms under different power supply conditions in a pre-stored fault and sub-health knowledge base when the branch insulation resistance and the bus insulation resistance meet the requirements and no AC power is introduced into the power supply bus, and determine the power supply status of the power supply branch feeder based on the comparison result.

[0025] Optionally, the processor is used to determine that the power supply branch feeder is working normally when the branch current is consistent with the current waveform in the normal power supply state in the fault and sub-health knowledge base; determine that there is a fault in the power supply branch feeder and control the electromagnetic air switch on the power supply branch feeder to disconnect when the branch current is consistent with the current waveform in the fault and sub-health knowledge base in the fault state; determine that the power supply branch is working in a sub-healthy state when the branch current is consistent with the current waveform in the sub-healthy power supply state in the fault and sub-health knowledge base; when the branch current is inconsistent with the current waveform in the fault and sub-health knowledge base, send a reminder message to the staff.

[0026] Optionally, the processor is used to determine the power supply status and report it to the monitoring platform.

[0027] Optionally, the signal conditioning circuit includes an insulation resistance detection control circuit, an AC inrush conditioning circuit, a bus voltage conditioning circuit, a bus current conditioning circuit, a branch current conditioning circuit, a branch voltage conditioning circuit, a branch leakage current conditioning circuit and an analog-to-digital converter;

[0028] The insulation resistance detection control circuit is electrically connected to the input resistance control circuit, the AC inrush detection circuit and the processor respectively, the AC inrush conditioning circuit is electrically connected to the AC inrush detection circuit and the analog-to-digital converter respectively, the bus voltage conditioning circuit is electrically connected to the input resistance control circuit and the analog-to-digital converter respectively, the bus current conditioning circuit is electrically connected to the second onboard current sensor and the analog-to-digital converter respectively, the branch current conditioning circuit is electrically connected to the first onboard current sensor and the analog-to-digital converter respectively, the branch voltage conditioning circuit is electrically connected to the voltage detection circuit and the analog-to-digital converter respectively, and the branch leakage current conditioning circuit is electrically connected to the onboard leakage current sensor and the analog-to-digital converter respectively;

[0029] The insulation resistance detection control circuit is used to obtain the insulation resistance value of the positive and negative busbars to the ground, and uses the resistance control circuit and the AC inrush detection circuit to obtain the voltage value of the positive and negative busbars to the ground when different resistance values ​​are input, and the busbar insulation resistance value is calculated by using this simultaneous equation group, and the busbar insulation resistance value is transmitted to the processor;

[0030] The AC inrush conditioning circuit is used to obtain the AC power, bus voltage value and ground voltage value inrushed into the power supply bus detected by the AC inrush detection circuit, and transmit the AC power, bus voltage value and ground voltage value inrushed into the power supply bus to the analog-to-digital converter;

[0031] The bus voltage conditioning circuit is used to obtain the resistance value detected by the resistor control circuit and transmit the resistance value to the analog-to-digital converter;

[0032] The bus current conditioning circuit is used to obtain the bus current detected by the second onboard current sensor and transmit the bus current to the analog-to-digital converter;

[0033] The branch current conditioning circuit is used to obtain the branch current detected by the first onboard current sensor and transmit the branch current to the analog-to-digital converter;

[0034] The branch voltage conditioning circuit is used to obtain the branch voltage detected by the voltage detection circuit and transmit the branch voltage to the analog-to-digital converter;

[0035] The branch leakage current conditioning circuit is used to obtain the branch leakage current detected by the on-board leakage current sensor and transmit the branch leakage current to the analog-to-digital converter;

[0036] The analog-to-digital converter is electrically connected to the processor;

[0037] The analog-to-digital converter is used to convert branch leakage current, branch current, branch voltage, bus current, AC current entering the power supply bus, bus voltage value, ground voltage value and resistance value into analog-to-digital values, and transmit them to the processor.

[0038] Optionally, the data processing board also includes a CAN communication interface, an RS485 communication interface and a short-range wireless module;

[0039] When the power supply monitoring system includes at least two monitoring units, the data processing boards of different monitoring units are connected in sequence through at least one of a CAN communication interface, an RS485 communication interface and a short-range wireless module;

[0040] The processor of the data processing board of each monitoring unit is used to transmit the power supply data and power supply status to the processor of the data processing board of the next-level monitoring unit, and the processor of the data processing board of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform; the power supply data includes branch leakage current, branch current, branch voltage, bus current, AC power entering the power supply bus, bus voltage value, voltage to ground value and resistance value.

[0041] Optionally, the data processing board also includes an Ethernet communication interface and a 4G / 5G module;

[0042] The processor of the data processing board of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform through at least one of the CAN communication interface, RS485 communication interface, Ethernet communication interface and 4G / 5G module.

[0043] Optionally, the data acquisition board and the data processing board are connected via a socket strip.

[0044] The power supply monitoring system provided by the embodiment of the present invention includes at least one monitoring unit, each monitoring unit includes a data acquisition board and a data processing board; the data acquisition board includes a power supply bus and a plurality of power supply branch feeders electrically connected to the power supply bus; each power supply branch feeder is provided with an electromagnetic air switch, an onboard leakage current sensor, a first onboard current sensor and a voltage detection circuit; the data processing board is provided with a processor and a signal conditioning circuit; in the same monitoring unit: the processor is electrically connected to the signal conditioning circuit, and the signal conditioning circuit is respectively connected to the electromagnetic air switch, the onboard leakage current sensor, the first onboard current sensor, the voltage detection circuit, the second onboard The current sensor, the AC inrush detection circuit and the resistor control circuit are electrically connected; the signal conditioning circuit is used to obtain the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush on the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value, and transmit the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush on the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value to the processor; the processor is used to control the switching state of the electromagnetic air switch according to the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush on the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value. In this embodiment, the electromagnetic air switch, the onboard leakage current sensor, the first onboard current sensor, the voltage detection circuit, the second onboard current sensor, the AC inrush detection circuit and the resistor control circuit are integrated on the data acquisition board, and the processor and the signal conditioning circuit are integrated on the data processing board, so that the entire circuit board can realize all functions without wiring connection, and is highly integrated, which greatly reduces the difficulty of on-site assembly and debugging, improves efficiency, and realizes comprehensive monitoring and protection of the power supply system. The monitoring unit adopts a modular design and is easy to expand and upgrade. At the same time, since all sensors and circuits are integrated on the data acquisition board, it is easy to maintain and replace. The processor can make intelligent decisions based on the collected data, control the switching state of the electromagnetic air switch, realize automatic protection and recovery of the circuit, improve the reliability and stability of the power supply system, and realize the high integration and intelligence of the DC feeder panel.

[0045] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 It is a module schematic diagram of a power supply monitoring system provided by an embodiment of the present invention;

[0048] Figure 2 is an expanded diagram of a power supply monitoring system provided by an embodiment of the present invention;

[0049] Figure 3 This is a flow chart of a power supply monitoring system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0052] An embodiment of the present invention provides a power supply monitoring system. Figure 1 is a schematic diagram of a power supply monitoring system provided by an embodiment of the present invention, with reference to Figure 1 , the power supply monitoring system includes:

[0053] At least one monitoring unit, each monitoring unit includes a data acquisition board 10 and a data processing board 20;

[0054] The data acquisition board 10 includes a power supply bus and a plurality of power supply branch feeders electrically connected to the power supply bus; each power supply branch feeder is provided with an electromagnetic air switch 11, an onboard leakage current sensor 12, a first onboard current sensor 13 and a voltage detection circuit 14;

[0055] The onboard leakage current sensor 12 is used to detect branch leakage current on the power supply branch feeder;

[0056] The first onboard current sensor 13 is used to detect the branch current on the power supply branch feeder;

[0057] The voltage detection circuit 14 is used to detect the branch voltage of the power supply branch;

[0058] The data acquisition board 10 is also provided with a second onboard current sensor 15, an AC inrush detection circuit 16 and a resistor control circuit 17, and the second onboard current sensor 15, the AC inrush detection circuit 16 and the resistor control circuit 17 are all electrically connected to the power supply bus;

[0059] The second onboard current sensor 15 is used to detect the bus current on the power supply bus;

[0060] The AC inrush detection circuit 16 is used to detect the AC inrush on the power supply bus, and detect the bus voltage value of the bus and the bus voltage value to ground;

[0061] The resistor control circuit 17 is used to control the resistance value between the busbar and the ground;

[0062] The data processing board 20 is provided with a processor 30 and a signal conditioning circuit 70;

[0063] In the same monitoring unit:

[0064] The processor 30 is electrically connected to the signal conditioning circuit 70, and the signal conditioning circuit 70 is electrically connected to the electromagnetic air switch 11, the onboard leakage current sensor 12, the first onboard current sensor 13, the voltage detection circuit 14, the second onboard current sensor 15, the AC inrush detection circuit 16 and the resistor control circuit 17 on the data acquisition board 10 respectively;

[0065] The signal conditioning circuit 70 is used to obtain the branch leakage current, branch current, branch voltage, bus current, AC current injected into the power supply bus, bus voltage value, voltage value to ground and resistance value, and transmit the branch leakage current, branch current, branch voltage, bus current, AC current injected into the power supply bus, bus voltage value, voltage value to ground and resistance value to the processor 30;

[0066] The processor 30 is used to control the switching state of the electromagnetic air switch 11 according to the branch leakage current, branch current, branch voltage, bus current, AC power flowing into the power supply bus, bus voltage value, ground voltage value and resistance value.

[0067] Among them, the onboard leakage current sensor 12 can be a closed-loop fluxgate onboard leakage current sensor 12, and the bus in the data acquisition board 10 supports DC110V, DC220V, DC48V and AC220V inputs, and can support a maximum continuous current input of 100A. The feeder output terminal 19 can support two types of 32A current output and 64A current output. The system takes power from the bus terminal, supports AC and DC input, and converts the 5V and ±12V power supplies required by the system through the AC / DC power supply module 50. The processor 30 uses a high-performance processor RK3568. While detecting the output of each branch feeder, it collects branch leakage current, branch current, branch voltage, bus current, AC power entering the power supply bus, bus voltage value, voltage to ground value and resistance value, and calculates information such as the operating status of each branch and bus. In the data acquisition board 10, IN1~IN12 are control signals sent by the data processing board 20 to the electromagnetic air switch 11, I1~I12 are leakage currents output by the onboard leakage current sensors 12 on multiple power supply branch feeders, which are transmitted to the branch leakage current conditioning circuit 27 in the data processing board 20; LI1~LI12 are currents output by the first onboard current sensors 13 on multiple power supply branch feeders, which are transmitted to the branch current conditioning circuit 25 in the data processing board 20; MI1 is the current output by the second onboard current sensor 15 on the negative bus, and MI2 is the current output by the second onboard current sensor 15 on the positive bus, and both MI1 and MI2 are transmitted to the bus current conditioning circuit 24 in the data processing board 20; LV1~LV12 are voltages output by the voltage detection circuit 14 on multiple power supply branch feeders, which are transmitted to the branch voltage conditioning circuit 26 in the data processing board 20.

[0068] Specifically, the electromagnetic air switch 11 on each power supply branch feeder controls the on-off state of the circuit, the indicator light 18 indicates whether each branch is in normal working condition, the onboard leakage current sensor 12 detects the branch leakage current, the first onboard current sensor 13 detects the branch current, the voltage detection circuit 14 detects the branch voltage, the second onboard current sensor 15 detects the bus current on the power supply bus, the AC inrush detection circuit 16 detects whether AC is inrushed into the power supply bus, and measures the bus voltage value and the voltage to the ground, the resistance control circuit 17 controls the resistance value between the bus and the ground according to preset conditions or instructions from the processor 30, which is used to adjust or detect certain specific electrical parameters; the signal conditioning circuit receives the analog signals transmitted from the various sensors and circuits on the data acquisition board 10, and performs filtering, amplification, conversion and other processing to ensure that the signal quality is suitable for subsequent processing by the processor 30. The processed signals (including branch leakage current, branch current, branch voltage, bus current, AC current entering the power supply bus, bus voltage value, ground voltage value and resistance value) are transmitted to the processor 30. The processor 30 receives the data transmitted by the signal conditioning circuit 70, analyzes and judges according to preset conditions. Based on the analysis results, the processor 30 decides whether it is necessary to control the switching state of the electromagnetic air switch 11 to achieve on-off control of the power supply branch, thereby protecting the circuit safety or responding to abnormal conditions.

[0069] The power supply monitoring system provided by the embodiment of the present invention includes at least one monitoring unit, each monitoring unit includes a data acquisition board 10 and a data processing board 20; the data acquisition board 10 includes a power supply bus and a plurality of power supply branch feeders electrically connected to the power supply bus; each power supply branch feeder is provided with an electromagnetic air switch 11, an onboard leakage current sensor 12, a first onboard current sensor 13 and a voltage detection circuit 14; the data processing board 20 is provided with a processor 30 and a signal conditioning circuit 70; in the same monitoring unit: the processor 30 is electrically connected to the signal conditioning circuit 70, and the signal conditioning circuit 70 is respectively connected to the electromagnetic air switch 11, the onboard leakage current sensor 12, the first onboard current sensor 13, the voltage detection circuit 14 on the data acquisition board 10 The detection circuit 14, the second on-board current sensor 15, the AC inrush detection circuit 16 and the resistor control circuit 17 are electrically connected; the signal conditioning circuit 70 is used to obtain the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush into the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value, and transmit the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush into the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value to the processor 30; the processor 30 is used to control the switching state of the electromagnetic air switch 11 according to the branch leakage current, the branch current, the branch voltage, the bus current, the AC inrush into the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value. In this embodiment, the electromagnetic air switch 11, the onboard leakage current sensor 12, the first onboard current sensor 13, the voltage detection circuit 14, the second onboard current sensor 15, the AC intrusion detection circuit 16 and the resistor control circuit 17 are integrated on the data acquisition board 10, and the processor 30 and the signal conditioning circuit 70 are integrated on the data processing board 20, so that the entire circuit board can realize all functions without wiring connection, and is highly integrated, which greatly reduces the difficulty of on-site assembly and debugging, improves efficiency, and realizes comprehensive monitoring and protection of the power supply system. The monitoring unit adopts a modular design and is easy to expand and upgrade. At the same time, since each sensor and acquisition circuit are integrated on the data acquisition board 10, it is easy to maintain and replace. The processor 30 can make intelligent decisions based on the collected data, control the switch state of the electromagnetic air switch 11, realize automatic protection and recovery of the circuit, improve the reliability and stability of the power supply system, and realize the high integration and intelligence of the DC feeder panel.

[0070] Optionally, the processor 30 is used to calculate the branch insulation resistance value of each branch, the branch power of each branch, the bus power and the bus insulation resistance value based on the branch leakage current, branch current, branch voltage, bus current, bus voltage value, voltage to ground and resistance value, and control the switching state of the electromagnetic air switch 11 based on the branch insulation resistance value, branch power, branch current, bus power, bus insulation resistance value and the alternating current entering the power supply bus.

[0071] Among them, the branch insulation resistance value is calculated by collecting the bus voltage to ground and the branch leakage current, and the simultaneous equations. The branch power is calculated by the product of the branch voltage and the branch current. The bus power is calculated by the product of the bus voltage and the bus current. The bus insulation resistance value is calculated by the resistance value between the positive and negative bus and the earth, and the sampling of the bus voltage to ground, and the simultaneous equations.

[0072] Specifically, the processor 30 receives various electrical parameters from the data acquisition board 10 through the signal conditioning circuit, including branch leakage current, branch current, branch voltage, bus current, bus voltage value, voltage to ground value and resistance value. The processor 30 verifies, filters and normalizes these raw data to ensure the accuracy and reliability of the data. The insulation resistance value of each branch is calculated by the simultaneous equations using the bus voltage to ground value and the branch leakage current. The insulation resistance value reflects the insulation performance of the branch to ground. The power of each branch is calculated by the power formula (P=UI) using the branch voltage and branch current, and the power value reflects the energy consumption of the branch. The power of the bus is calculated by the power formula (P=UI) using the bus voltage and bus current, and the power value reflects the energy consumption of the bus. The insulation resistance value of the bus is calculated by the simultaneous equations using the resistance value between the positive and negative busbars and the earth and the bus voltage to ground value through a specific algorithm. The processor 30 compares the calculated branch insulation resistance value, branch power, bus power, branch current and bus insulation resistance value with the set value, or determines whether AC power is injected into the power supply bus. If the branch insulation resistance value, branch power, bus power, branch current and bus insulation resistance value exceed the limit or AC power is injected into the power supply bus, the processor 30 makes a control decision. The processor 30 sends a control signal to the electromagnetic air switch 11 to disconnect the corresponding branch or bus to protect the safety of the circuit and equipment. The processor can also report abnormal conditions and various data to the monitoring platform.

[0073] Optionally, the processor 30 is configured to:

[0074] When the branch insulation resistance exceeds the first set resistance value, the electromagnetic air switch 11 on the feeder line of the power supply branch is controlled to be disconnected;

[0075] When the insulation resistance value of the busbar exceeds the second set resistance value, or when AC power is introduced into the power supply busbar, the electromagnetic air switches 11 on all power supply branch feeders connected to the busbar are controlled to be disconnected;

[0076] When the branch power or bus power exceeds the set power value, an alarm is issued.

[0077] Specifically, after the power supply monitoring system is started, the processor 30 is initialized and loads the preset first set resistance value, second set resistance value and set power value and other parameters. The processor 30 connects and monitors various sensors in the power supply system, and calculates data such as branch insulation resistance, bus insulation resistance, whether AC is injected into the power supply bus, bus power and branch power. If the insulation resistance value of a power supply branch exceeds the first set resistance value, the processor 30 immediately determines that the branch has hidden dangers such as leakage or insulation damage, and the processor 30 sends a control signal to disconnect the electromagnetic air switch 11 on the feeder of the power supply branch to cut off the power supply of the faulty branch and prevent potential safety accidents. If the bus insulation resistance value exceeds the second set resistance value, or AC is detected on the power supply bus, the processor 30 determines that the bus system is unstable or the equipment is damaged, and the processor 30 sends a control signal to disconnect all electromagnetic air switches 11 on the feeder of all power supply branches connected to the bus to ensure the safety of the entire power supply system. If the power of a power supply branch or bus power exceeds the set power value, the processor 30 determines that the branch or bus may be overloaded or fluctuating abnormally, and there is a risk of damaging equipment or causing a fire. The processor 30 does not directly cut off the power supply, but instead sends an alarm signal (such as an audible and visual alarm, sending a text message or email notification, etc.) to remind the operation and maintenance personnel to take timely measures to deal with the overload problem.

[0078] Optionally, the processor 30 is used to compare each branch current with the current waveforms under different power supply conditions in a pre-stored fault and sub-health knowledge base when the branch insulation resistance and the bus insulation resistance meet the requirements and there is no AC current entering the power supply bus, and determine the power supply status of the power supply branch feeder based on the comparison result.

[0079] Among them, the current waveform data of each fault load when simulating abnormal working conditions can be used to establish a fault and sub-health knowledge base of each load.

[0080] Specifically, when the branch insulation resistance and bus insulation resistance meet the requirements and there is no AC current on the power supply bus, the processor 30 collects the current data of each branch, and the processor 30 compares the collected current waveform with the current waveforms under different power supply states in the pre-stored fault and sub-health knowledge base, and identifies whether the current waveform of the current power supply branch feeder matches a certain fault or sub-health state in the knowledge base. Based on the comparison results, the processor 30 determines the power supply state of the power supply branch feeder. If the current waveform matches the fault waveform in the knowledge base, it is judged that there is a fault in the branch; if it matches the sub-health waveform, it is judged that the branch is in a sub-health state; if it matches the normal waveform, it is judged that the branch is in a normal power supply state.

[0081] Optionally, the processor 30 is used to determine that the power supply branch feeder is working normally when the branch current is consistent with the current waveform in the normal power supply state in the fault and sub-health knowledge base; determine that there is a fault in the power supply branch feeder and control the electromagnetic air switch 11 on the power supply branch feeder to disconnect when the branch current is consistent with the current waveform in the fault and sub-health knowledge base in the fault state; determine that the power supply branch is working in a sub-healthy state when the branch current is consistent with the current waveform in the sub-healthy power supply state in the fault and sub-health knowledge base; when the branch current is inconsistent with the current waveform in the fault and sub-health knowledge base, send a reminder message to the staff.

[0082] Specifically, if the current waveform is consistent with the normal power supply state waveform in the knowledge base, the processor 30 determines that the branch feeder is working normally. If the current waveform is consistent with the fault state waveform in the knowledge base, the processor 30 determines that the branch feeder is faulty. The processor 30 will immediately send a control signal to disconnect the electromagnetic air switch 11 on the branch feeder to cut off the power supply of the faulty branch to prevent the fault from spreading or causing a larger safety accident. If the current waveform is consistent with the sub-healthy power supply state waveform in the knowledge base, the processor 30 determines that the branch feeder is working in a sub-healthy state. When it is determined that the branch feeder is faulty or sub-healthy, the processor 30 will immediately send an alarm signal (such as an audible and visual alarm, sending a text message or email notification, etc.) to remind the operation and maintenance personnel to take timely measures to handle it.

[0083] Optionally, the processor 30 is configured to determine the power supply status and report it to a monitoring platform.

[0084] Specifically, the processor 30 compares and analyzes the collected data using a knowledge base to determine the power supply status, and then sends the data to the monitoring platform via a communication network.

[0085] Optionally, the signal conditioning circuit includes an insulation resistance detection control circuit 21, an AC inrush conditioning circuit 22, a bus voltage conditioning circuit 23, a bus current conditioning circuit 24, a branch current conditioning circuit 25, a branch voltage conditioning circuit 26, a branch leakage current conditioning circuit 27 and an analog-to-digital converter 28;

[0086] The insulation resistance detection control circuit 21 is electrically connected to the resistance control circuit 17, the AC inrush detection circuit 16 and the processor 30 respectively, the AC inrush conditioning circuit 22 is electrically connected to the AC inrush detection circuit 16 and the analog-to-digital converter 28 respectively, the bus voltage conditioning circuit 23 is electrically connected to the resistance control circuit 17 and the analog-to-digital converter 28 respectively, the bus current conditioning circuit 24 is electrically connected to the second onboard current sensor 15 and the analog-to-digital converter 28 respectively, the branch current conditioning circuit 25 is electrically connected to the first onboard current sensor 13 and the analog-to-digital converter 28 respectively, the branch voltage conditioning circuit 26 is electrically connected to the voltage detection circuit 14 and the analog-to-digital converter 28 respectively, and the branch leakage current conditioning circuit 28 is electrically connected to the onboard leakage current sensor 12 and the analog-to-digital converter 28 respectively;

[0087] The insulation resistance detection control circuit 21 is used to obtain the insulation resistance value of the positive and negative busbars to the ground, and uses the resistance control circuit 17 and the AC inrush detection circuit 16 to obtain the voltage value of the positive and negative busbars to the ground when different resistance values ​​are input, and calculates the insulation resistance value of the busbars by using this set of simultaneous equations, and transmits the insulation resistance value of the busbars to the processor 30;

[0088] The AC inrush conditioning circuit 22 is used to obtain the AC inrush current, bus voltage value and ground voltage value on the power supply bus detected by the AC inrush detection circuit 16, and transmit the AC inrush current, bus voltage value and ground voltage value on the power supply bus to the analog-to-digital converter 28;

[0089] The bus voltage conditioning circuit 23 is used to obtain the resistance value detected by the resistor control circuit 17 and transmit the resistance value to the analog-to-digital converter 28;

[0090] The bus current conditioning circuit 24 is used to obtain the bus current detected by the second onboard current sensor 15 and transmit the bus current to the analog-to-digital converter 28;

[0091] The branch current conditioning circuit 25 is used to obtain the branch current detected by the first onboard current sensor 13 and transmit the branch current to the analog-to-digital converter 28;

[0092] The branch voltage conditioning circuit 26 is used to obtain the branch voltage detected by the voltage detection circuit 14 and transmit the branch voltage to the analog-to-digital converter 28;

[0093] The branch leakage current conditioning circuit 27 is used to obtain the branch leakage current detected by the onboard leakage current sensor 12 and transmit the branch leakage current to the analog-to-digital converter 28;

[0094] The analog-to-digital converter 28 is electrically connected to the processor 30;

[0095] The analog-to-digital converter 28 is used to perform analog-to-digital conversion on branch leakage current, branch current, branch voltage, bus current, AC current entering the power supply bus, bus voltage value, ground voltage value and resistance value, and transmit them to the processor 30.

[0096] Specifically, the insulation resistance detection control circuit 21 obtains the insulation resistance value of the positive and negative busbars to the ground, and uses the resistance control circuit 17 and the AC inrush detection circuit 16 to obtain the voltage value of the positive and negative busbars to the ground when different resistance values ​​are input, and uses this set of simultaneous equations to calculate the busbar insulation resistance value, and transmits the busbar insulation resistance value to the processor 30. The AC inrush detection circuit 16 detects whether AC power is injected into the power supply busbar, and measures the busbar voltage value and the voltage value to the ground. The AC inrush conditioning circuit 22 conditions the AC power injected into the power supply busbar, the busbar voltage value and the voltage value to the ground, and transmits the conditioned signal to the analog-to-digital converter 28. The busbar voltage conditioning circuit 23 obtains the resistance value related to the busbar voltage through the resistance control circuit 17. The busbar current conditioning circuit 24 obtains the busbar current value from the second onboard current sensor 15, and the conditioned busbar voltage and current signals are transmitted to the analog-to-digital converter 28. The branch current conditioning circuit 25 obtains the branch current value from the first onboard current sensor 13, and the branch voltage conditioning circuit 26 obtains the branch voltage value from the voltage detection circuit 14. The conditioned branch current and voltage signals are transmitted to the analog-to-digital converter 28. The branch leakage current conditioning circuit 27 obtains the branch leakage current value from the onboard leakage current sensor 12, and the conditioned branch leakage current signal is transmitted to the analog-to-digital converter 28. The analog-to-digital converter 28 receives all analog signals from the signal conditioning circuit and converts all analog signals into digital signals. The converted digital signals are transmitted to the processor 30 for subsequent processing and analysis. The processor 30 determines the state of the power supply system based on the received digital signal. If the processor 30 detects any abnormality or fault, the processor 30 will trigger the corresponding early warning or alarm mechanism to notify the operation and maintenance personnel or the monitoring platform.

[0097] Figure 2 is an expanded diagram of a power supply monitoring system provided by an embodiment of the present invention, with reference to Figure 2 The data processing board 20 further includes a CAN communication interface 31, an RS485 communication interface 32 and a short-range wireless module 33;

[0098] When the power supply monitoring system includes at least two monitoring units, the data processing boards 20 of different monitoring units are connected in sequence through at least one of the CAN communication interface 31, the RS485 communication interface 32 and the short-range wireless module 33;

[0099] The processor 30 of the data processing board 20 of each monitoring unit is used to transmit the power supply data and power supply status to the processor 30 of the data processing board 20 of the next-level monitoring unit, and the processor 30 of the data processing board 20 of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform; the power supply data includes branch leakage current, branch current, branch voltage, bus current, AC power entering the power supply bus, bus voltage value, voltage to ground value and resistance value.

[0100] Specifically, the data processing board 20 of each monitoring unit collects the branch leakage current, branch current, branch voltage, bus current, AC current entering the power supply bus, bus voltage value, ground voltage value and resistance value of the power supply system through their own sensors and signal conditioning circuits. The processor 30 pre-processes the collected data to ensure the accuracy and reliability of the data. The processor 30 transmits the processed power supply data and power supply status to the processor 30 of the data processing board 20 of the next level monitoring unit through the selected communication interface, step by step, until it is transmitted to the last level monitoring unit. The data transmission between different monitoring units is realized through the CAN communication interface 31, the RS485 communication interface 32 or the short-range wireless module 33. The processor 30 of the last level monitoring unit will collect the data transmitted by all the upper-level monitoring units, and summarize and organize all the received data and its own power supply data and power supply status. The processor 30 of the last level monitoring unit uploads the summarized power supply data and power supply status to the monitoring platform through the selected communication method.

[0101] Optionally, the data processing board 20 further includes an Ethernet communication interface 34 and a 4G / 5G module 35;

[0102] The processor 30 of the data processing board 20 of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform through at least one of the CAN communication interface 31, the RS485 communication interface 32, the Ethernet communication interface 34 and the 4G / 5G module 35.

[0103] Specifically, the processor 30 of the last-level monitoring unit collects, summarizes and organizes the data transmitted by all upper-level monitoring units. The processor 30 of the last-level monitoring unit uploads the summarized power supply data and power supply status to the monitoring platform through at least one of the CAN communication interface 31, RS485 communication interface 32, Ethernet communication interface 34 and 4G / 5G module 35, and the monitoring platform can further analyze, store and display the power supply data and power supply status.

[0104] Since a single data acquisition board 10 supports 12-way branch feeder output, if 36-way or 60-way straight line output is required, it is only necessary to use multiple monitoring units (composed of a data acquisition board 10 and a data processing board 20) to expand through the CAN communication interface 31 and the RS485 communication interface 32. The expanded data is processed by a data processing board to achieve efficient, unified processing and uploading of data. The 4G / 5G module 35 of the data processing board 20 can send the collected raw data and data processing results to the monitoring platform in a unified manner. Data can also be transmitted through the Ethernet communication interface 34.

[0105] Optionally, the data acquisition board 10 and the data processing board 20 are connected via a socket strip 40 .

[0106] Specifically, the two boards are connected into a whole through the 30-pin socket 40 terminals in the data acquisition board 10 and the 30-pin socket 40 terminals in the data processing board 20 .

[0107] Figure 3 is a flow chart of a power supply monitoring system provided by an embodiment of the present invention, with reference to Figure 3 . First, determine the number of branches required and configure the system, including determining the number of monitoring units required, and electrically connecting the processor to the signal conditioning circuit. After the system self-check is completed, collect data from the bus and each branch, including voltage, current, leakage current, etc. The processor calculates the insulation resistance of the bus and branch respectively, and determines whether there is AC intrusion. If the insulation resistance exceeds the limit or there is AC intrusion, the processor controls the electromagnetic air switch to disconnect the abnormal branch output; if the insulation resistance does not exceed the limit or there is no AC intrusion, the processor records the data of each feeder output load in real time. The data of each feeder output load is compared with the fault and sub-health knowledge base for analysis. If not, notify the manual processing of the on-site fault; if it is consistent, the comparison result is consistent with the fault model, the processor controls the electromagnetic air switch to disconnect the abnormal branch output, and report the information to the monitoring platform; the comparison result is consistent with the sub-health model, the processor issues a sub-health prediction, and reports the information to the monitoring platform; the data is normal, the branch output is normal, and the information is reported to the monitoring platform through wireless transmission.

[0108] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0109] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A power supply monitoring system, characterized in that: include: At least one monitoring unit, each monitoring unit includes a data acquisition board and a data processing board; The data acquisition board includes a power supply bus and a plurality of power supply branch feeders electrically connected to the power supply bus; each of the power supply branch feeders is provided with an electromagnetic air switch, an onboard leakage current sensor, a first onboard current sensor and a voltage detection circuit; The onboard leakage current sensor is used to detect the branch leakage current on the power supply branch feeder; The first onboard current sensor is used to detect the branch current on the power supply branch feeder; The voltage detection circuit is used to detect the branch voltage of the power supply branch; The data acquisition board is also provided with a second onboard current sensor, an AC inrush detection circuit and a resistor control circuit, and the second onboard current sensor, the AC inrush detection circuit and the resistor control circuit are all electrically connected to the power supply bus; The second onboard current sensor is used to detect the bus current on the power supply bus; The AC inrush detection circuit is used to detect the AC inrush on the power supply bus, and detect the bus voltage value of the bus and the bus voltage value to ground; The resistor control circuit is used to control the resistance value between the busbar and the ground; The data processing board is provided with a processor and a signal conditioning circuit; In the same monitoring unit: The processor is electrically connected to the signal conditioning circuit, and the signal conditioning circuit is electrically connected to the electromagnetic air switch, the onboard leakage current sensor, the first onboard current sensor, the voltage detection circuit, the second onboard current sensor, the AC inrush detection circuit and the resistor control circuit on the data acquisition board respectively; The signal conditioning circuit is used to obtain the branch leakage current, the branch current, the branch voltage, the bus current, the AC current injected into the power supply bus, the bus voltage value, the voltage to ground value and the resistance value, and transmit the branch leakage current, the branch current, the branch voltage, the bus current, the AC current injected into the power supply bus, the bus voltage value, the voltage to ground value and the resistance value to the processor; The processor is used to control the switching state of the electromagnetic air switch according to the branch leakage current, the branch current, the branch voltage, the bus current, the alternating current entering the power supply bus, the bus voltage value, the voltage to ground and the resistance value.

2. The power supply monitoring system according to claim 1, characterized in that: The processor is used to calculate the branch insulation resistance value of each branch, the branch power of each branch, the bus power and the bus insulation resistance value according to the branch leakage current, the branch current, the branch voltage, the bus current, the bus voltage value, the voltage to ground and the resistance value, and control the switching state of the electromagnetic air switch according to the branch insulation resistance value, branch power, branch current, bus power, the bus insulation resistance value and the alternating current entering the power supply bus.

3. The power supply monitoring system according to claim 2, characterized in that: The processor is used to: When the insulation resistance of the branch exceeds a first set resistance value, the electromagnetic air switch on the feeder of the power supply branch is controlled to be disconnected; When the insulation resistance value of the busbar exceeds the second set resistance value, or when AC power is introduced into the power supply busbar, the electromagnetic air switches on all power supply branch feeders connected to the busbar are controlled to be disconnected; When the branch power or the bus power exceeds the set power value, an alarm is issued.

4. The power supply monitoring system according to claim 2, characterized in that: The processor is used to compare each branch current with the current waveforms under different power supply conditions in a pre-stored fault and sub-health knowledge base when the branch insulation resistance and the bus insulation resistance both meet the requirements and no alternating current is introduced into the power supply bus, and determine the power supply status of the power supply branch feeder based on the comparison result.

5. The power supply monitoring system according to claim 4, characterized in that: The processor is used to determine that the power supply branch feeder is working normally when the branch current is consistent with the current waveform in the normal power supply state in the fault and sub-health knowledge base; when the branch current is consistent with the current waveform in the fault state in the fault and sub-health knowledge base, determine that there is a fault in the power supply branch feeder and control the electromagnetic air switch on the power supply branch feeder to disconnect; when the branch current is consistent with the current waveform in the sub-healthy power supply state in the fault and sub-health knowledge base, determine that the power supply branch is working in a sub-healthy state; When the branch current is inconsistent with the current waveform in the fault and sub-health knowledge base, a reminder message is sent to the staff.

6. The power supply monitoring system according to claim 5, characterized in that: The processor is used to determine the power supply status and report it to the monitoring platform.

7. The power supply monitoring system according to claim 1, characterized in that: The signal conditioning circuit includes an insulation resistance detection control circuit, an AC inrush conditioning circuit, a bus voltage conditioning circuit, a bus current conditioning circuit, a branch current conditioning circuit, a branch voltage conditioning circuit, a branch leakage current conditioning circuit and an analog-to-digital converter; The insulation resistance detection control circuit is electrically connected to the resistance control circuit, the AC inrush detection circuit and the processor respectively, the AC inrush conditioning circuit is electrically connected to the AC inrush detection circuit and the analog-to-digital converter respectively, the bus voltage conditioning circuit is electrically connected to the resistance control circuit and the analog-to-digital converter respectively, the bus current conditioning circuit is electrically connected to the second onboard current sensor and the analog-to-digital converter respectively, the branch current conditioning circuit is electrically connected to the first onboard current sensor and the analog-to-digital converter respectively, the branch voltage conditioning circuit is electrically connected to the voltage detection circuit and the analog-to-digital converter respectively, and the branch leakage current conditioning circuit is electrically connected to the onboard leakage current sensor and the analog-to-digital converter respectively; The insulation resistance detection control circuit is used to obtain the insulation resistance value of the positive and negative busbars to the ground, and use the resistance control circuit and the AC inrush detection circuit to obtain the voltage value of the positive and negative busbars to the ground when different resistance values ​​are input, and use this simultaneous equation group to calculate the insulation resistance value of the busbar, and transmit the insulation resistance value of the busbar to the processor; The AC inrush conditioning circuit is used to obtain the AC power, bus voltage value and ground voltage value inrushed into the power supply bus detected by the AC inrush detection circuit, and transmit the AC power, bus voltage value and ground voltage value inrushed into the power supply bus to the analog-to-digital converter; The bus voltage conditioning circuit is used to obtain the resistance value detected by the resistor control circuit and transmit the resistance value to the analog-to-digital converter; The bus current conditioning circuit is used to obtain the bus current detected by the second onboard current sensor and transmit the bus current to the analog-to-digital converter; The branch current conditioning circuit is used to obtain the branch current detected by the first onboard current sensor and transmit the branch current to the analog-to-digital converter; The branch voltage conditioning circuit is used to obtain the branch voltage detected by the voltage detection circuit and transmit the branch voltage to the analog-to-digital converter; The branch leakage current conditioning circuit is used to obtain the branch leakage current detected by the onboard leakage current sensor and transmit the branch leakage current to the analog-to-digital converter; The analog-to-digital converter is electrically connected to the processor; The analog-to-digital converter is used to perform analog-to-digital conversion on the branch leakage current, the branch current, the branch voltage, the bus current, the alternating current entering the power supply bus, the bus voltage value, the voltage to ground and the resistance value, and transmit them to the processor.

8. The power supply monitoring system according to claim 1, characterized in that: The data processing board also includes a CAN communication interface, an RS485 communication interface and a short-range wireless module; When the power supply monitoring system includes at least two monitoring units, the data processing boards of different monitoring units are connected in sequence through at least one of a CAN communication interface, an RS485 communication interface and a short-range wireless module; The processor of the data processing board of each monitoring unit is used to transmit the power supply data and power supply status to the processor of the data processing board of the next-level monitoring unit, and the processor of the data processing board of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform; the power supply data includes the branch leakage current, the branch current, the branch voltage, the bus current, the AC power entering the power supply bus, the bus voltage value, the voltage value to the ground and the resistance value.

9. The power supply monitoring system according to claim 8, characterized in that: The data processing board also includes an Ethernet communication interface and a 4G / 5G module; The processor of the data processing board of the last-level monitoring unit is used to transmit the received power supply data and power supply status to the monitoring platform through at least one of the CAN communication interface, RS485 communication interface, Ethernet communication interface and 4G / 5G module.

10. The power supply monitoring system according to claim 1, characterized in that: include: The data acquisition board and the data processing board are connected via a socket strip.

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