Ultra-high voltage line overall protection configuration

June 28, 2025

The UHV (Ultra High Voltage) line protection system is equipped with a full-line, high-speed longitudinal protection scheme. When a fault occurs on the line, both ends of the protection devices must exchange signals to perform logical decision-making. On the high-frequency protection side, blocking, tripping, or permission signals are transmitted via high-frequency channels. In contrast, the longitudinal differential protection uses fiber optic channels to send critical information such as current data, plate status, and remote trip commands to the opposite side. This ensures that the longitudinal protection operates effectively, making the channel an essential component. Any channel failure necessitates the immediate shutdown of the protection system to prevent misoperation. The overall configuration of the longitudinal protection is illustrated in the diagram below.

Overall Configuration of Line Longitudinal Protection

As shown in the figure, different types of protection use distinct communication channels. The type of channel directly determines the transmission equipment used. For consistent and reliable operation, the protection models on both sides of the same line must be identical, and the performance parameters of the corresponding channel equipment must match precisely. This ensures that both sides of the protection system respond in synchronization, maintaining the integrity and effectiveness of the entire protection strategy.

Battery Energy Storage System

Battery Energy Storage System (BESS) is a complex system that integrates multiple technologies and devices to store electrical energy in the form of chemical energy and release it for use when needed. The following is a detailed description of the purpose of the BESS class:

I. Basic definition
BESS is a system that uses lithium batteries, lead batteries, etc., as energy storage carriers to store electricity for a certain period of time and supply electricity when needed. The power provided by the system has functions such as smooth transition, peak cutting and valley filling, frequency regulating and voltage regulating, etc. It is of great significance to improve the stability, reliability and flexibility of the power grid.

Second, system composition
BESS mainly consists of the following parts:

Battery Array:
It is the core part of BESS and is used to store electrical energy. Common energy storage batteries include lithium-ion batteries, lead-acid batteries and so on.
The performance of the battery directly affects the efficiency and reliability of the entire energy storage system.
Battery Management System (BMS) :
Responsible for intelligent management and maintenance of each battery unit, prevent the battery from overcharging and overdischarging, and extend the service life of the battery.
Monitor the battery status, including voltage, current, temperature and other parameters, to ensure the safe operation of the battery pack.
Energy Storage converters (PCS) :
It is one of the key devices in BESS, responsible for converting direct current in the battery pack to alternating current, or alternating current to direct current, to meet the needs of different application scenarios.
PCS has the ability to control the flow of electric energy bidirectional, and can flexibly adjust the power and voltage of the grid.
Local controller:
Responsible for local control and management of BESS, including data collection, condition monitoring, fault diagnosis and other functions.
The local controller can also communicate with the external energy management system (EMS) to receive instructions and perform energy scheduling and power control.
Power distribution system:
Devices such as switches, circuit breakers, cables, etc. are included to connect BESS to the power grid or other loads.
Distribution systems need to ensure the safe transmission and distribution of electrical energy.
Auxiliary equipment:
Including temperature control system, fire protection system, lighting system, monitoring system and so on.
These devices are used to ensure the safe operation and routine maintenance of BESS.
3. Technical characteristics
High efficiency:
BESS has high energy conversion efficiency and charge and discharge efficiency, which can maximize the use of stored electrical energy.
Flexibility:
BESS can be flexibly configured and expanded according to actual requirements to adapt to different scales and scenarios.
Reliability:
With advanced BMS and PCS technology, BESS is able to ensure the safe operation and efficient utilization of battery packs and improve the reliability of the system.
Environmental protection:
BESS uses renewable energy for energy storage and power supply, reducing dependence on traditional energy sources and environmental pollution.

BESS Lifepo4 battery, solar power energy system, 3.2V lithium battery cell

Foshan Keylewatt Technology Co., LTD , https://www.klwenergy.com