0 Introduction

In today's digital age, the stability of power supply is crucial for all types of users. As a key link in power transmission, the monitoring system of 110kV and below substations directly affects the reliability of power supply. And microcomputer protection devices are playing an irreplaceable core role in this field, bringing full intelligent monitoring solutions to user substations.

The microcomputer protection device can be regarded as the "intelligent guardian" of the power system, which is a high-tech crystallization that integrates modern computer technology, network communication technology, and digital signal processing technology. Nowadays, it has completely replaced traditional relay protection and become the "safety brain" for ensuring power safety in user substations.

Guarding 110kV and below user substations, microcomputer protection devices create a safe defense line

In modern power systems, 110kV and below user substations are like key nodes in the urban network, providing a continuous supply of electricity for industrial production, commercial activities, and residential life. Ensuring the reliable, safe, and orderly operation of these substations is an important cornerstone of stable power supply, and microcomputer protection devices are indispensable "guardians" among them.

1.1Intelligent monitoring, comprehensive protection of electrical safety

needleA comprehensive monitoring solution is the key to ensuring electrical safety for substations with a capacity of 110kV and below. By using microcomputer protection devices, arc protection devices, control devices, contact temperature measurement products, partial discharge monitoring devices, power quality monitoring/multifunctional instruments, environmental and other secondary equipment, various information in the substation is collected to the monitoring system/EMS energy efficiency management platform for analysis, warning and control. This is like equipping a substation with pairs of sharp "eyes" and intelligent "brains" to capture various operational states in real-time.

As the core force, microcomputer protection devices can provide full protection for key equipment such as lines and main transformers. Taking Acrel-1000 substation comprehensive automation system as an example, AM5SE series microcomputer protection devices are configured in 35kV and 10kV distribution systems. In terms of incoming line protection, each 35kV incoming cabinet is equipped with a line protection AM5SE-F (if fiber optic differential protection is required, AM6-LD is configured, consistent with the opposite side). When a circuit fault occurs, the circuit breaker in the cabinet can be quickly tripped to cut off the fault and prevent the spread and expansion of the fault.

1.2Accurate monitoring to ensure power quality

ExceptThe microcomputer protection device also has precise power quality monitoring function for quick response to faults. Install the power quality monitoring device APView500 in the 35kV incoming cabinet, which can monitor power quality in real-time, including steady-state data such as voltage harmonics and imbalance, voltage deviation, frequency deviation, voltage fluctuations and flicker, as well as transient data such as voltage rise, fall, and short-term interruption. When abnormal power quality is detected, fault recording and data recording are triggered to provide data support for subsequent power quality analysis. This is like conducting a "comprehensive health check" on the quality of electricity, ensuring that the power supply remains in a "healthy state" at all times.

1.3Centralized management to improve operational efficiency

In order to observe and centrally manage the operation status of the step-down transformer in real time, facilitate the installation and maintenance of the secondary monitoring equipment of the step-down transformer, and improve the reliability and sensitivity of protection, the 35kV/10kV main transformer circuit adopts a centralized screen grouping method with a complete set of main transformer protection devices, and is equipped with one main transformer protection screen. The cabinet is located in the electrical monitoring room and is equipped with differential protection devices, high backup protection devices, low backup protection devices, high side measurement and control devices, low side measurement and control devices, transformer temperature controllers, gear transmitters and conversion switches, pressure plates, air switches and other control equipment. This centralized screen grouping method is like an efficient "command center", allowing staff to have a clear understanding of the operation of the main transformer, detect problems in a timely manner, and handle them.

1.4The better the performance, the more reliable the defense line

withAM5SE/6Taking the series microcomputer protection device as an example, it is suitable for 110KV, 35KV, and 10KV substations and has many outstanding performance characteristics. Adopting a 4U standard aluminum profile chassis with a combination plug-in structure, the chassis is designed with rear plug-in and each functional module is individually designed, with strong and weak electrical separation, strong anti-interference ability, and easy on-site maintenance. Multi CPU intelligent plugin design, with input and output plugins for real-time self checking, capable of detecting each relay coil. The connection between plugins is based on CANBUS bus, reducing the number of connections between plugins and detecting poor connections in real-time. The dual 32-bit system has high system redundancy, and the protection function uses a 32-bit floating-point DSP processor produced by Texas Instruments. Programs and data run on-chip, with fast running speed and high reliability.

3Conclusion

inIn the operation of 110kV and below user substations, microcomputer protection devices have become an important force in ensuring the safe and stable operation of substations with their advantages of intelligent monitoring, precise monitoring, centralized management, and excellent performance. Whether it is the continuous operation of industrial production or the comfortable use of electricity in residents' lives, they cannot do without the silent protection of microcomputer protection devices. Let us join hands and use advanced microcomputer protection technology to contribute to the safe and stable operation of the power system, and together embrace a better future of electricity.