Microgrid system

A microgrid refers to a small-scale power generation and distribution system composed of distributed power sources, energy storage devices, energy conversion devices, loads, monitoring and protection devices, etc. The proposal of microgrids aims to achieve flexible and efficient application of distributed power sources, and solve the problem of grid connection of a large number and diverse forms of distributed power sources. The development and extension of microgrids can fully promote the large-scale integration of distributed power sources and renewable energy, achieve highly reliable supply of multiple forms of energy to loads, and is an effective way to achieve an active distribution network, enabling the transition from traditional grids to smart grids.

Overview

A microgrid refers to a small-scale power generation and distribution system composed of distributed power sources, energy storage devices, energy conversion devices, loads, monitoring and protection devices, etc. The proposal of microgrids aims to achieve flexible and efficient application of distributed power sources, and solve the problem of grid connection of a large number and diverse forms of distributed power sources. The development and extension of microgrids can fully promote the large-scale integration of distributed power sources and renewable energy, achieve highly reliable supply of multiple forms of energy to loads, and is an effective way to achieve an active distribution network, enabling the transition from traditional grids to smart grids.

General principle

(1) Progressiveness and forward-looking: the system construction adopts advanced design scheme that conforms to the future development trend.

(2) Security: Adopting a complete security architecture to avoid a security vacuum.

(3) The system should have expandability in terms of system capacity, communication capability, processing capability, etc., which can facilitate product upgrades, replacements, and functional expansion. The system adopts advanced technology, methods, and equipment to provide open standard interfaces for third-party applications. In future upgrades, it can effectively protect existing investments and has a high comprehensive performance price ratio.

(4) The system can operate normally 24 hours a day, 365 days a year, and all equipment has high reliability and excellent performance.

(5) The system has high security and confidentiality, and various forms of illegal intrusion into the system are prevented through graded protection, control of data storage permissions, and network security isolation.

(6) The system administrator is able to maintain and manage the system, and during maintenance and repair, it does not affect the overall business operation of the system. At the same time, all documents of the recording system must be complete, accurate, and consistent, and the accuracy of physical connections must be accurately recorded in the corresponding documents. In addition to accurately recording themselves, various documents must also ensure logical consistency between each other. Facilitating user maintenance after handover.

System Network Structure

Microgrid systemThe network architecture specifically includes the electrical wiring network structure within the microgrid, the power supply system (DC/AC power supply and three-phase/single-phase power supply), the node locations of the corresponding loads and distributed power sources in the microgrid, and so on. A microgrid is a small medium and low voltage power grid that combines various distributed power generation to provide electricity to local loads. It can operate in both grid connected and islanded modes, and can improve the reliability of power supply on the load side. Its power supply mode can be divided into AC type, DC type, and AC/DC hybrid type. The system architecture diagram is shown in the following figure:

Main Features

(1) A microgrid is an autonomous system that can achieve self-control, protection, and management. As a complete power system, it relies on its own control and management to achieve power balance control, system operation optimization, fault detection and protection, power quality governance, and other functions.

(2) The proposal of microgrids aims to achieve flexible and efficient application of distributed power sources, and solve the problem of grid connection of a large number and diverse forms of distributed power sources. The development and extension of microgrids can fully promote the large-scale integration of distributed power sources and renewable energy, achieve highly reliable supply of multiple forms of energy to loads, and is an effective way to achieve an active distribution network, enabling the transition from traditional grids to smart grids.

(3) The power sources in microgrids are mostly distributed power sources with small capacities, including small units with power electronic interfaces, including micro gas turbines, fuel cells, photovoltaic cells, small wind turbines, as well as energy storage devices such as supercapacitors, flywheels, and batteries. They are connected to the user side and have the characteristics of low cost, low voltage, and low pollution.

(4) The system has cross platform running characteristics and can run on Windows, Linux, and domestic operating system platforms.

Feature Introduction

(1) Active power and reactive power control (P-Q control). By adjusting the phase difference between the grid connected inverter voltage and the network voltage, the active power is controlled, and by adjusting the voltage amplitude of the grid connected inverter, the reactive power is controlled.

(2) Voltage regulation based on differential adjustment. It is not suitable to use P-Q control when there are a large number of micro power sources connected, as without on-site voltage control, voltage or reactive power oscillations may occur. Any effective error in the voltage setting value in a microgrid may result in significant reactive power commutation, causing the voltage value of the microgrid to exceed the standard.

(3) Fast loading and energy storage. The inertia of the generator in the microgrid is small, and the response time of the power supply is long. When the microgrid is disconnected from the main grid and runs in an ancient path, energy storage devices must be provided to maintain the normal operation of the microgrid.

(4) Frequency modulation control When operating as an isolated island in a microgrid, frequency difference control should be adopted to change the proportion of load borne by the cutting unit, so that each unit can handle it in a certain proportion during regulation without exceeding the standard.

summary

Microgrid is a new type of autonomous power system that enables large-scale application of distributed generation technology and effectively improves the reliability of system power supply.Microgrid systemIt mainly realizes modular, customized, and systematic functions, based on QTouch cross platform configuration software as the foundation, and can customize diverse system interfaces. According to customer requirements, establish a unified communication standard protocol to achieve various functions such as data collection, management, and control.

case

Microgrid Energy Management System - Off Grid Operation, located in 4 different locations as follows:

Location 1: Ali region, Xizang, with an altitude of about 4400 meters.

Location 2: Hotan Prefecture, Xinjiang, with an altitude of approximately 5380 meters.

Location 3: Hotan Prefecture, Xinjiang, with an altitude of approximately 5390 meters.

Location 4: Hotan Prefecture, Xinjiang, with an altitude of approximately 5400 meters.