CN103576057B - Insulated on-line monitoring system and method - Google Patents

Abstract

The invention provides a kind of insulated on-line monitoring system and method, this system comprises: remote monitoring platform, host computer, CAN turn Ethernet Adaptation Unit and at least one on-the-spot insulating monitoring unit; Described on-the-spot insulating monitoring unit is for monitoring the state of insulation of the electrical equipment being arranged on traction substation; Described in each, on-the-spot insulating monitoring unit is connected with one end that described CAN turns Ethernet Adaptation Unit by CAN, the other end that described CAN turns Ethernet Adaptation Unit is connected with one end of described host computer, and the other end of described host computer is connected with described remote monitoring platform by database.There is high reliability and monitoring accuracy, thus realize the permanently effective monitoring to insulation of electrical installation state; Further, can also monitor multiple insulation parameters of multiple stage electrical equipment simultaneously simultaneously, thus reduce monitoring cost, alleviate the working strength of monitoring personnel.

Description

Insulation online monitoring system and method

technical field

The invention belongs to the technical field of electrical equipment monitoring, and in particular relates to an insulation on-line monitoring system and method.

Background technique

With the rapid development of the current railway industry, higher requirements are put forward for the traction substation used in railway transportation. Specifically: the primary electrical equipment used in the traction substation needs to meet the requirements of long online time, power failure detection and The maintenance time is short; moreover, it is also necessary to warn in advance of the possible failure of electrical equipment due to insulation problems, so as to reduce the possible loss of electrical equipment due to insulation problems. Therefore, it is of great practical significance to develop an online insulation monitoring system for electrical equipment to monitor the insulation status of electrical equipment, so as to ensure the electrical safety performance of electrical equipment in actual working conditions.

At present, the insulation monitoring system of electrical equipment uses portable instruments to monitor the insulation status of electrical equipment. state. The main defects of this method are: (1) poor real-time performance, unable to effectively monitor the insulation state of electrical equipment for a long time; (2) low monitoring efficiency, when it is necessary to monitor multiple insulation parameters of a certain electrical equipment, Need to use various testing instruments, which not only increases the monitoring cost, but also increases the work intensity of the monitoring personnel.

Contents of the invention

Aiming at the defects existing in the prior art, the present invention provides an insulation on-line monitoring system and method, which has high reliability and monitoring accuracy, thereby realizing long-term and effective monitoring of the insulation status of electrical equipment; moreover, it is also possible to simultaneously monitor multiple Multiple insulation parameters of electrical equipment are monitored at the same time, thereby reducing monitoring costs and reducing the workload of monitoring personnel.

The technical scheme that the present invention adopts is as follows:

The invention provides an insulation on-line monitoring system, comprising: a remote monitoring platform, a host computer, a CAN-to-Ethernet adapter and at least one on-site insulation monitoring unit; the on-site insulation monitoring unit is used to monitor electrical equipment installed in traction substations Insulation status; each of the on-site insulation monitoring units is connected to one end of the CAN-to-Ethernet adapter through the CAN bus, and the other end of the CAN-to-Ethernet adapter is connected to one end of the host computer, and the host computer’s The other end is connected with the remote monitoring platform through a database.

Preferably, the electrical equipment includes a primary side transformer bushing, a current transformer, a voltage transformer and a lightning arrester.

Preferably, each on-site insulation monitoring unit includes: a main controller, a power supply module, a storage module, an analog-to-digital conversion module, at least one micro-current sensor, at least one voltage sensor, at least one temperature sensor, at least one humidity sensor and at least one A heater; the main controller is respectively connected with the power module, the storage module, the temperature sensor, the humidity sensor and the heater; the main controller is also connected through the analog-to-digital conversion module It is connected with the micro-current sensor, and the main controller is also connected with the voltage sensor through the analog-to-digital conversion module.

Preferably, the main controller is connected to the heater through a drive circuit and a relay in sequence; the main controller is an LPC1768 controller; the power module is a digital power module or an analog power module; the storage module is EEPROM memory; the analog-to-digital conversion module is an AD7656 16-bit analog-to-digital conversion module; the micro-current sensor is a zero-flux core-through type micro-current sensor; the main controller is also equipped with a CAN interface, an RS485 interface, and an Ethernet interface RS485 Network port, RS232 debugging interface, I2C interface, SSP0 interface.

The present invention provides a method for applying the above-mentioned insulation on-line monitoring system, comprising the following steps:

S1, the on-site insulation monitoring unit collects and stores the insulation parameter information of the monitored electrical equipment, wherein the data format of the insulation parameter information is a data format conforming to the CAN bus network transmission protocol; when receiving the information sent by the host computer When a data call is requested, the on-site insulation monitoring unit uploads the insulation parameter information to the CAN-to-Ethernet adapter through the CAN bus network;

S2, the CAN-to-Ethernet adapter converts the data format of the insulation parameter information into a data format conforming to the Ethernet transmission protocol, obtains the insulation parameter information conforming to the Ethernet transmission protocol, and then converts the data format conforming to the Ethernet transmission protocol The insulation parameter information is transmitted to the host computer through Ethernet;

S3, the host computer analyzes and judges the received insulation parameter information, obtains an insulation state evaluation report of the monitored electrical equipment, and stores the insulation state evaluation report in the database;

S4. The remote monitoring platform reads and displays the insulation state evaluation report corresponding to the monitored electrical equipment from the database.

Preferably, the insulation parameter information includes leakage current information and dielectric loss angle equivalent information; in S1, the on-site insulation monitoring unit collects and stores the insulation parameter information of the monitored electrical equipment specifically as follows:

S11. Each of the micro-current sensors collects original sampling information in an analog signal format of the monitored electrical equipment;

S12, the micro-current sensor sends the original sampling information to the analog-to-digital conversion module, and the analog-to-digital conversion module converts the original sampling information into sampling information in digital signal format, and then serially inputs it to the in the main controller;

S13, the main controller analyzes and judges the sampling information of the digital signal format, and obtains a leakage current value and a dielectric loss angle equivalent value of the monitored electrical equipment;

S14, the main controller stores the leakage current value and dielectric loss angle and other values in the storage module.

Preferably, before S1, the following steps are further included: the host computer sends a notification message to start sampling to the on-site insulation monitoring unit; and/or

In S2, the data call request includes a call request for all insulation parameter information, and a call request for specific insulation parameter information; and/or

After S1, it also includes: when the network communication fails or the insulation parameter information stored by the on-site insulation monitoring unit is lost, the host computer sends a notification message to start the watchdog reset function to the on-site insulation monitoring unit.

Preferably, in S3, the host computer analyzes and judges the received insulation parameter information, and obtains the insulation state evaluation report of the monitored electrical equipment, specifically:

The host computer establishes an insulation dynamic model, inputs the received insulation parameter information into the insulation dynamic model, and then obtains an insulation state evaluation report of the monitored electrical equipment by running the insulation dynamic model; wherein, the The parameters used in the insulation dynamic model include the voltage of the electrical equipment, the temperature of the environment where the electrical equipment is located, the humidity of the environment where the electrical equipment is located, the leakage current of the electrical equipment, and the dielectric loss angle of the electrical equipment.

Preferably, after S3, it also includes:

S5. When the host computer finds that the insulation state of the monitored electrical equipment is lower than a preset limit value, an alarm signal is sent.

The beneficial effects of the present invention are as follows:

The insulation on-line monitoring system and method provided by the present invention are very suitable for places with serious electromagnetic field interference such as traction substations, and have high reliability and monitoring accuracy, thereby realizing long-term effective monitoring of the insulation state of electrical equipment; and, also It can monitor multiple insulation parameters of multiple electrical equipments at the same time, thereby reducing the monitoring cost and reducing the work intensity of monitoring personnel.

Description of drawings

Fig. 1 is the structural representation of the insulation on-line monitoring system provided by the present invention;

Fig. 2 is a schematic structural diagram of an on-site insulation monitoring unit provided by the present invention.

detailed description

The insulation on-line monitoring system and method provided by the present invention are described in detail below in conjunction with the accompanying drawings:

As shown in Figure 1, the present invention provides an insulation on-line monitoring system, comprising: a remote monitoring platform, a host computer, a CAN-to-Ethernet adapter, and at least one on-site insulation monitoring unit; the on-site insulation monitoring unit is used to monitor the The insulation state of the electrical equipment in the substation; each of the on-site insulation monitoring units is connected to one end of the CAN-to-Ethernet adapter through the CAN bus, and the other end of the CAN-to-Ethernet adapter is connected to one end of the host computer , the other end of the host computer is connected to the remote monitoring platform through a database. Wherein, in the present invention, the electrical equipment includes, but is not limited to, primary side transformer bushings, current transformers, voltage transformers and lightning arresters. Through the CAN-to-Ethernet adapter, the mutual communication function between the CAN bus network and the Ethernet network is realized.

As shown in Figure 2, each of the on-site insulation monitoring units includes: a main controller, a power module, a storage module, an analog-to-digital conversion module, at least one micro-current sensor, at least one voltage sensor, at least one temperature sensor, at least one humidity sensor and at least one heater; the main controller is respectively connected with the power module, the storage module, the temperature sensor, the humidity sensor and the heater; the main controller is also connected through the module The digital conversion module is connected with the micro-current sensor, and the main controller is also connected with the voltage sensor through the analog-to-digital conversion module. Wherein, as shown in Fig. 2, the main controller is connected with the heater through the driving circuit and the relay in turn; the main controller is an LPC1768 controller; the power module is a digital power module or an analog power module, and more Specifically, AC220V power supply can be used for power supply, which can be converted into a suitable voltage by using the Saiside switching power supply. Two 12V power supplies are used to form a positive and negative 12V power supply to power the micro-current sensor, and the positive 12V power supply is converted into the required analog 5V voltage through two chips of 7809 and 7805; a 5V-turned Saiside power supply is used as the digital circuit part Provide 5V voltage, and provide 3.3V voltage through LM2576. The storage module is an EEPROM memory; the analog-to-digital conversion module is an AD7656 16-bit analog-to-digital conversion module, specifically, the AD7656 high-precision 16-digit analog-to-digital conversion chip can be used to control the sampling frequency of the AD chip by hardware phase-locked loop technology , the maximum sampling rate of the chip is 250Kps. The control chip LPC1768 uses an external interrupt to start SSP0, and communicates with the analog-to-digital conversion module. The micro-current sensor is a zero-flux through-core micro-current sensor. Since the electromagnetic environment of the traction substation is very harsh, in order to be able to accurately measure the leakage current at the microampere level and the dielectric loss angle at a small angle, non-contact measurement is selected , that is, through the magnetic flux core-type micro-current sensor, it has a very good function of tracking the amplitude and phase of the tiny leakage current without changing the original wiring of the primary electrical equipment; the main controller is also equipped with a CAN interface , RS485 interface, Ethernet interface RS485 network port, RS232 debugging interface, I2C interface, SSP0 interface. The on-site insulation monitoring unit is installed at the monitoring site of the substation to complete the collection, calculation and analysis of various online monitoring signals, and communicate with the host computer through the CAN bus, CAN-to-Ethernet adapter, and Ethernet to upload the insulation parameters of electrical equipment. The upper computer is used to manage each on-site insulation monitoring unit to realize fault diagnosis, fault alarm, historical data storage, trend analysis and report printing functions. Moreover, the on-site insulation monitoring unit needs to be independent from other parts in terms of installation structure and circuit function, so as to ensure that the stable operation of the electrical equipment to be monitored will not be affected.

The number of micro-current sensors and voltage sensors installed in the on-site insulation monitoring unit is adjusted according to actual needs. When 3 micro-current sensors and 3 voltage sensors are connected, the voltage and current of 3 electrical equipment can be collected and calculated, and named respectively For Isulator1, Isulator2 and Isulator3, the data of 6 channels of AD is serially read through the SSP0 interface, where Timer2 captures the frequency of the measurement signal, Timer1 automatically outputs a square wave to control the sampling rate, and Timer0 is used as a function of sampling and returning to the 50HZ period when the measurement period signal is lost . Through this installation method, the parallel processing capability of the on-site insulation monitoring unit can be improved.

The insulation on-line monitoring system provided by the present invention is divided into a three-layer structure: the first layer is a remote monitoring platform, and the on-site monitoring data can be viewed through the IE browsing interface; the second layer is a host computer, which communicates with the on-site insulation monitoring unit through a CAN-to-Ethernet adapter , to control its sampling, data call and parameter modification; the third layer is the on-site insulation monitoring unit, which is mainly used to collect the insulation parameter information of the monitored electrical equipment.

The method for applying the above-mentioned insulation on-line monitoring system provided by the present invention includes the following steps:

S1, the on-site insulation monitoring unit collects and stores the insulation parameter information of the monitored electrical equipment, wherein the data format of the insulation parameter information is a data format conforming to the CAN bus network transmission protocol; when receiving the information sent by the host computer When a data call is requested, the on-site insulation monitoring unit uploads the insulation parameter information to the CAN-to-Ethernet adapter through the CAN bus network;

Wherein, the insulation parameter information includes leakage current information and dielectric loss angle equivalent information; in this step, the on-site insulation monitoring unit collects and stores the insulation parameter information of the monitored electrical equipment specifically as follows:

S11. Each of the micro-current sensors collects original sampling information in an analog signal format of the monitored electrical equipment;

S12, the micro-current sensor sends the original sampling information to the analog-to-digital conversion module, and the analog-to-digital conversion module converts the original sampling information into sampling information in digital signal format, and then serially inputs it to the in the main controller;

S13, the main controller analyzes and judges the sampling information of the digital signal format, and obtains a leakage current value and a dielectric loss angle equivalent value of the monitored electrical equipment;

S14, the main controller stores the leakage current value and dielectric loss angle and other values in the storage module.

S2, the CAN-to-Ethernet adapter converts the data format of the insulation parameter information into a data format conforming to the Ethernet transmission protocol, obtains the insulation parameter information conforming to the Ethernet transmission protocol, and then converts the data format conforming to the Ethernet transmission protocol The insulation parameter information is transmitted to the host computer through Ethernet;

S3, the host computer analyzes and judges the received insulation parameter information, obtains an insulation state evaluation report of the monitored electrical equipment, and stores the insulation state evaluation report in the database;

Wherein, in S3, the host computer analyzes and judges the received insulation parameter information, and obtains the insulation state evaluation report of the monitored electrical equipment as follows:

The host computer establishes an insulation dynamic model, inputs the received insulation parameter information into the insulation dynamic model, and then obtains an insulation state evaluation report of the monitored electrical equipment by running the insulation dynamic model; wherein, the The parameters used in the insulation dynamic model include the voltage of the electrical equipment, the temperature of the environment where the electrical equipment is located, the humidity of the environment where the electrical equipment is located, the leakage current of the electrical equipment, and the dielectric loss angle of the electrical equipment.

Since the change of the insulation performance of the insulating material of electrical equipment is affected by many factors, it is very complicated. The present invention establishes the mathematical relationship that the absolute performance follows the changes of factors such as the primary equipment voltage, ambient temperature, ambient humidity, and its own historical cumulative temperature rise. The insulation dynamic model provides a strong support for the primary equipment of the traction substation from periodic maintenance to condition maintenance.

S4. The remote monitoring platform reads and displays the insulation state evaluation report corresponding to the monitored electrical equipment from the database.

S5. When the host computer finds that the insulation state of the monitored electrical equipment is lower than a preset limit value, an alarm signal is sent. This step can be located after S3 or S4.

In addition, in the present invention, before S1, the following steps are also included: the host computer sends a notification message of starting sampling to the on-site insulation monitoring unit; and/or

In S2, the data call request includes a call request for all insulation parameter information, and a call request for specific insulation parameter information; and/or

After S1, it also includes: when the network communication fails or the insulation parameter information stored by the on-site insulation monitoring unit is lost, the host computer sends a notification message to start the watchdog reset function to the on-site insulation monitoring unit.

As the traction substation is a place with a very harsh electromagnetic environment, especially the electromagnetic field suffered by the process layer equipment installed near the primary equipment is more serious, but because the process layer equipment is a distributed system, it is also the It is the most direct device for raw data collection and action execution of the network system. Therefore, it is necessary to ensure the synchronization requirements and sufficient real-time performance between network devices. Through the CAN bus technology, it is suitable for the environment where the on-site equipment of the substation is widely distributed and is seriously disturbed by the electromagnetic field.

In summary, the insulation on-line monitoring system and method provided by the present invention are very suitable for places with severe electromagnetic field interference such as traction substations, and have high reliability and monitoring accuracy, thereby realizing long-term effective monitoring of the insulation status of electrical equipment. monitoring; moreover, it is also possible to monitor multiple insulation parameters of multiple electrical equipment at the same time, thereby reducing the monitoring cost and reducing the work intensity of the monitoring personnel.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (7)

1. An insulation on-line monitoring system, characterized in that it comprises: a remote monitoring platform, a host computer, a CAN to Ethernet adapter and at least one on-site insulation monitoring unit; the on-site insulation monitoring unit is used to monitor the The insulation status of the electrical equipment; each of the on-site insulation monitoring units is connected to one end of the CAN-to-Ethernet adapter through the CAN bus, and the other end of the CAN-to-Ethernet adapter is connected to one end of the host computer, and the The other end of the host computer is connected with the remote monitoring platform through a database; Wherein, each of the on-site insulation monitoring units includes: a main controller, a power supply module, a storage module, an analog-to-digital conversion module, at least one micro-current sensor, at least one voltage sensor, at least one temperature sensor, at least one humidity sensor and at least one heater; the main controller is respectively connected with the power module, the storage module, the temperature sensor, the humidity sensor and the heater; the main controller is also connected with the analog-to-digital conversion module The micro-current sensor is connected, and the main controller is also connected to the voltage sensor through the analog-to-digital conversion module; The main controller is connected to the heater through a drive circuit and a relay in turn; the main controller is an LPC1768 controller; the power module is a digital power module or an analog power module; the storage module is an EEPROM memory; The analog-to-digital conversion module is an AD7656 16-bit analog-to-digital conversion module; the micro-current sensor is a zero-flux through-core micro-current sensor; the main controller is also equipped with a CAN interface, an RS485 interface, an Ethernet interface RS485 network port, RS232 debugging interface, I2C interface, SSP0 interface. 2 . The insulation on-line monitoring system according to claim 1 , wherein the electrical equipment includes primary side transformer bushings, current transformers, voltage transformers and lightning arresters. 3. A method for applying the insulation on-line monitoring system according to any one of claims 1-2, characterized in that it comprises the following steps: S1, the on-site insulation monitoring unit collects and stores the insulation parameter information of the monitored electrical equipment, wherein the data format of the insulation parameter information is a data format conforming to the CAN bus network transmission protocol; when receiving the information sent by the host computer When a data call is requested, the on-site insulation monitoring unit uploads the insulation parameter information to the CAN-to-Ethernet adapter through the CAN bus network; S2, the CAN-to-Ethernet adapter converts the data format of the insulation parameter information into a data format conforming to the Ethernet transmission protocol, obtains the insulation parameter information conforming to the Ethernet transmission protocol, and then converts the data format conforming to the Ethernet transmission protocol The insulation parameter information is transmitted to the host computer through Ethernet; S3, the host computer analyzes and judges the received insulation parameter information, obtains an insulation state evaluation report of the monitored electrical equipment, and stores the insulation state evaluation report in the database; S4. The remote monitoring platform reads and displays the insulation state evaluation report corresponding to the monitored electrical equipment from the database. 4. The method according to claim 3, wherein the insulation parameter information includes leakage current information and dielectric loss angle equivalent information; in S1, the on-site insulation monitoring unit collects and stores the insulation of the monitored electrical equipment The parameter information is specifically: S11. Each of the micro-current sensors collects original sampling information in an analog signal format of the monitored electrical equipment; S12, the micro-current sensor sends the original sampling information to the analog-to-digital conversion module, and the analog-to-digital conversion module converts the original sampling information into sampling information in digital signal format, and then serially inputs it to the in the main controller; S13, the main controller analyzes and judges the sampling information of the digital signal format, and obtains a leakage current value and a dielectric loss angle equivalent value of the monitored electrical equipment; S14, the main controller stores the leakage current value and dielectric loss angle and other values in the storage module. 5. The method of claim 3, wherein, Before S1, the following steps are also included: the host computer sends a notification message of starting sampling to the on-site insulation monitoring unit; and/or In S2, the data call request includes a call request for all insulation parameter information, and a call request for specific insulation parameter information; and/or After S1, it also includes: when the network communication fails or the insulation parameter information stored by the on-site insulation monitoring unit is lost, the host computer sends a notification message to start the watchdog reset function to the on-site insulation monitoring unit. 6. The method according to claim 3, characterized in that, in S3, the host computer analyzes and judges the received insulation parameter information, and obtains the insulation state evaluation report of the monitored electrical equipment as follows: The host computer establishes an insulation dynamic model, inputs the received insulation parameter information into the insulation dynamic model, and then obtains an insulation state evaluation report of the monitored electrical equipment by running the insulation dynamic model; wherein, the The parameters used in the insulation dynamic model include the voltage of the electrical equipment, the temperature of the environment where the electrical equipment is located, the humidity of the environment where the electrical equipment is located, the leakage current of the electrical equipment, and the dielectric loss angle of the electrical equipment. 7. The method according to claim 3, characterized in that, after S3, further comprising: S5. When the host computer finds that the insulation state of the monitored electrical equipment is lower than a preset limit value, an alarm signal is sent.