CN105203700A - Real-time early warning system for internal environment of high-voltage cable branch boxes - Google Patents

Abstract

In the real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention, an induction power supply, an odor sensor, a smoke sensor and a monitoring device are arranged in each distribution box, and the induction energy collection power supply, the odor sensor and the smoke sensor are all connected to the monitoring device , the monitoring device is connected to the host computer or mobile monitoring equipment through wireless communication. The early warning system uses odor sensors and smoke sensors to monitor the internal environment of the high-voltage cable distribution box in real time, and uses the concentration of odor and smoke as the criterion for early warning of cable joint failures in the distribution box. The equipment is low in cost and easy to install and use. , the threshold can be adjusted according to the actual situation, the dual monitoring of smell and smoke can avoid false alarms and false alarms, it is suitable for power supply and distribution networks in large and medium-sized cities, especially suitable for complex environments (such as large external smoke, or external smell is very strong) Miscellaneous, or smog, etc.) for real-time early warning of high-voltage cable distribution boxes.

Description

Real-time early warning system for internal environment of high-voltage cable distribution box

technical field

The invention relates to a power cable transmission and distribution network, in particular to high-voltage cable joint fault handling, and more specifically to a real-time early warning system for the internal environment of a high-voltage cable distribution box.

Background technique

The power industry is the foundation and leading industry of national economic construction, and plays a pivotal role in national economic construction. The fundamental task of the power system is to supply electric energy "safely, reliably, and with high quality". With the rapid development of our country's national economy, the improvement of urban construction and industrial modernization, the electric power industry, which is the lifeline of the national economy, has encountered unprecedented challenges.

In the power supply system of cities and large and medium-sized enterprises, more and more power cables are used for power transmission and distribution. When the power supply distance is long, there are usually cable joints on the line. In practice, there is a cable joint every 300 meters for the medium and high voltage power supply cables in the city. In many cases, in order to reduce the difficulty of technology and construction, the cable joints are installed in the power supply in the cable distribution box. The cable distribution box is an indoor or outdoor device, which is usually installed on the street, roadside or residential area, and is used for branching, branching, connecting or converting cable lines.

The cable distribution box is widely used for its economy, reliability, and convenient maintenance. Its fully insulated and fully sealed structural characteristics greatly reduce line faults. As the hub of electric energy collection and distribution, the distribution box plays an important role in the safe operation of the urban power grid. However, in many cases, in order to reduce the difficulty of technology and construction, the cable joints are installed in the power supply cable distribution box. Cable joints are prone to overheating under long-term, high-current (overload) operating conditions, resulting in accidents. If it is small, it will cause a long-term power outage to the user, and if it is serious, it may cause a chain reaction of the peripheral equipment of the cable line to fail, and may even cause part or most of the power distribution system to be paralyzed, seriously affecting the safe and reliable operation of the power system and causing huge losses. Economic losses. Cable joints have become one of the weak links in the safe operation of the power supply cable network. Most of the accidents in the cable distribution box are caused by the failure of the cable joint in the distribution box. According to statistics, the accident rate of cable joints accounts for 90% of cable accidents.

At present, it is mainly judged whether a fault occurs by detecting the temperature of the cable joint. This method mainly has the following disadvantages:

1. High cost: Due to the large number of cable joints inside the distribution box, there are generally more than 6 cables in the distribution box, and each cable needs to be installed with a sensor, so the number of sensors is large and the equipment costs are large.

2. Difficult to implement: At present, the internal cable joint structure of the distribution box does not reserve space for installing a temperature sensor.

3. Difficulty in installation: the temperature sensor needs to directly contact the core of the high-voltage cable conductor, and it is difficult to insulate the installation position.

Contents of the invention

In order to overcome the deficiencies of the prior art and to predict possible faults in advance, the present invention provides a real-time early warning system for the internal environment of the high-voltage cable distribution box.

Cable joint failure is actually a gradual process, and temperature changes cannot reflect this gradual change. It takes a long time for the cable to age from insulation, overheat to cause a fire. During this period, it is often accompanied by the smell from the aging of the insulation layer, the smell and smoke from burning, and a large amount of very unpleasant smell. Lots of smoke. Therefore, in view of this characteristic, a real-time early warning system for the internal environment of the cable distribution box can be developed, which uses odor and smoke as monitoring objects to predict the possibility of failure in advance and determine whether the failure occurs.

Design a low-cost, easy-to-implement early warning system for the internal environment of the cable distribution box. By detecting the concentration of odor and smoke inside the distribution box, the internal cable joints of the distribution box will be detected before the failure of the cable joint inside the distribution box. The purpose of the present invention is to carry out accurate early warning of faults, notify the staff to overhaul the cable joints, and prevent the occurrence of faults in the cable joints.

In order to achieve the above object, the real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention, an induction energy harvesting power supply, an odor sensor, a smoke sensor and a monitoring device are arranged in each of the distribution boxes, and the induction energy harvesting power supply, the odor sensor and the smoke sensor The sensors are all connected to the monitoring device, and the monitoring device is connected to the host computer or mobile monitoring equipment through wireless communication.

The odor sensor and smoke sensor are used to detect the environmental conditions in the cable distribution box in real time, and convert the detected odor and smoke concentration into signals and transmit them to the monitoring device respectively. The monitoring device monitors the odor and smoke transmitted by the odor sensor and smoke sensor in real time. Smoke concentration signal, when the signal received by the monitoring device exceeds the preset threshold, the monitoring device will automatically send different alarm signals (used to distinguish between smell and smoke) and transmit them to the host computer management system through network communication or directly send SMS to the monitoring personnel , After the upper computer management system receives the alarm signal, the monitoring personnel will notify the operating personnel to overhaul the cable joints inside the distribution box.

In order to more accurately judge the smell in the high-voltage cable distribution box and avoid false alarms due to other smells (such as the smell of mouse excrement and urine), the early warning system of the present invention uses the smell that is sensitive to the smell emitted by high-voltage cables. sensor.

The monitoring device of the present invention comprises a single-chip microcomputer and a GSM/GPRS module connected thereto. The single-chip microcomputer is used to receive the signal transmitted by the odor sensor and the smoke sensor, and compare (preset threshold) and process it. When the alarm signal needs to be sent, the alarm signal will be sent to the GSM/GPRS module.

Therefore, in the present invention, the inductive energy harvesting power supply, the odor sensor and the smoke sensor are all connected to the single-chip microcomputer of the monitoring device.

The GSM/GPRS module in the monitoring device communicates with the host computer or mobile monitoring equipment through the wireless network.

The induction power supply is used to provide working power for the monitoring device, which includes an induction coil and a rectification circuit connected thereafter, a filter circuit and a voltage stabilization circuit. The induction energy harvesting power supply uses the principle of electromagnetic induction to induce AC voltage from the high-voltage bus or line through the induction coil, and then supplies power to the monitoring device after rectification, filtering, and voltage stabilization to solve the power supply problem of the monitoring device.

In order to facilitate signal processing, an A/D conversion circuit is set between the odor sensor and smoke sensor and the monitoring device (that is, the single-chip microcomputer) to convert the odor and smoke concentration data into a stable signal.

In order to facilitate on-site viewing and handling of faults, the early warning system of the present invention also includes an on-site human-computer interaction circuit connected to the monitoring device.

In the real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention, the odor sensor and the smoke sensor are both non-contact measuring devices, which will not introduce strong electricity into the measuring device, so there is no need to monitor the internal environment of the early warning system. The measuring device adopts high-grade insulation measures.

The advantages of the present invention are:

1. Each distribution box only needs one odor sensor and smoke sensor, the number of sensors is greatly reduced, and the cost is reduced.

2. Since there is enough space inside the distribution box to install odor sensors and smoke sensors, it is easy to detect the internal environmental conditions of the distribution box.

3. Since the cable joint failure is a gradual process, in this process, the aging of the cable insulation inside the distribution box will cause obvious changes in the concentration of odor and smoke in the distribution box. Therefore, through the detection of odor and smoke , can accurately give early warning to the fault of the cable joint.

4. Through the double monitoring of smell and smoke, double alarm, and display them differently on the host computer or the mobile phone of the monitoring personnel, so that the monitoring personnel can analyze and judge the type of failure, the possibility of failure and the degree of failure. When there is an odor alarm but no smoke alarm, it means that the fault is forming, but it is not very serious. At this time, timely maintenance can prevent the fault from happening. When there is a smoke alarm but no smell alarm, it is possible that the smoke is not from high-voltage cables, but caused by external influences (such as the smoke generated by burning other materials around the distribution box into the distribution box), and then there is no need to disconnect Electric maintenance. If there is both an odor alarm and a smoke alarm, it is almost a safe bet that the distribution box has failed, or that an external critical condition has occurred that has compromised the distribution box, making it possible for the distribution box to fail immediately.

The real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention uses an odor sensor and a smoke sensor to monitor the internal environment of the high-voltage cable distribution box in real time, and uses the concentration of odor and smoke as the judgment of the early warning of the cable joint failure in the distribution box. According to the data, the equipment is low in cost, easy to install and use, and the threshold can be adjusted according to the actual situation. The dual monitoring of odor and smoke can avoid false alarms and false alarms. It is suitable for power supply and distribution networks in large and medium cities, especially in complex environments ( Real-time early warning of high-voltage cable distribution boxes such as large external smog, heavy external smell, or smog.

Description of drawings

Fig. 1 is a structural block diagram of the real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention.

Detailed ways

see picture 1. The odor sensor is connected to an interface of the single-chip microcomputer in the detection device through the A/D conversion circuit, and the smoke sensor is connected to an interface of the single-chip microcomputer in the detection device through the A/D conversion circuit. According to the comparison results, it is determined whether an alarm is required. When the threshold is exceeded and an alarm is required, the single-chip microcomputer sends the alarm signal to the GSM/GPRS module, which then sends it wirelessly to the host computer or mobile monitoring equipment through the network.

The induction energy harvesting power supply including the induction coil and the rectification circuit connected thereafter, the filter circuit and the voltage stabilization circuit is connected to the single-chip microcomputer.

The on-site human-computer interaction circuit is connected to the single-chip microcomputer.

The real-time early warning system for the internal environment of the high-voltage cable distribution box of the present invention is placed in the high-voltage cable distribution box without direct contact with the high-voltage cables. The induction coil of the induction energy harvesting power supply is placed near the high-voltage bus to induce AC voltage.

Claims (8)

1. High-Voltage Cable Branching Case internal environment real-time early warning system, comprise sensor, it is characterized in that: induction energy fetching power supply, smell sensor, smoke transducer and monitoring device are set in each distribution box, induction energy fetching power supply, smell sensor are all connected monitoring device with smoke transducer, and monitoring device connects host computer or mobile monitoring device by radio communication.

2. early warning system according to claim 1, is characterized in that: smell sensor selects the smell sensor to the odor-sensitive that high voltage cable sends.

3. early warning system according to claim 1, is characterized in that: the GSM/GPRS module that monitoring device comprises single-chip microcomputer and is attached thereto.

4. the early warning system according to claim 1 or 3, is characterized in that: induction energy fetching power supply, smell sensor and smoke transducer are all connected the single-chip microcomputer of monitoring device.

5. the early warning system according to claim 1 or 3, is characterized in that: the GSM/GPRS module in monitoring device is communicated to connect by wireless network and host computer or mobile monitoring device.

6. early warning system according to claim 1, is characterized in that: induction energy fetching power supply comprises inductive coil and latter linked rectification circuit, filtering circuit and mu balanced circuit.

7. early warning system according to claim 1, is characterized in that: between monitoring device, arrange A/D change-over circuit at smell sensor and smoke transducer.

8. early warning system according to claim 1, is characterized in that: also comprise the on-the-spot man-machine interaction circuit be connected with monitoring device.