Intelligent low voltage apparatus must meet the excellent performance, reliable operation, product volume small, the modularization design, communication, energy conservation and environmental protection requirements, such as to have protection, monitoring, communication, self-diagnosis, display, and other functions, it is necessary to realize intelligent power grid。
1. Basic intelligent technology of low-voltage electrical appliances
At present, the basic meaning of intelligent low-voltage electrical appliances mainly includes the following functions: protection and control function is all ready, both electrical parameter measurement, external fault detection, alarm and switch the self internal fault diagnosis and alarm, system running state monitoring, electricity use management functions such as part (or function). To this end, the following techniques need to be studied in depth.
1) what are the intelligent functions of various low-voltage electrical appliances based on their low-voltage power distribution, control system status and role? How do you implement these functions?
2) research and development of intelligent low-voltage electrical appliances; Research on intelligent functional test equipment and test method。
3) research on the integrated technology of intelligent low-voltage electrical appliances; The intelligent function of different low voltage appliances is taken when multiple intelligent electrical appliances are integrated. When multiple functions overlap, coordinate and cooperate with each other.
4) research on the reliability of intelligent low-voltage electrical appliances (including EMC technology)。
2. Research on the communication technology of intelligent electrical appliances
The powerful function of intelligent low-voltage electric appliances must depend on the network of low voltage distribution and control system. For this reason, the communication requirement of low voltage electrical apparatus is put forward. In order to meet the network requirements, a series of technical studies will be involved.
(1) study on the standardization of networked appliances and systems.
(2) seamless connection between high, medium and low voltage distribution systems.
(3) research and development of intelligent network system supporting accessories。
(4) research on the typical scheme and overall solution of intelligent network system.
(5) study on the test method of the communication apparatus and the development of relevant test equipment and establish the corresponding test base.
3。 Intelligent distribution system overcurrent protection technology
When abnormal current of power distribution system occurs, low voltage electrical appliances should be disconnected in time. In order to limit the power failure to a minimum range, low voltage appliances should be selectively disconnected. It is especially important for smart grid to remove fault circuits quickly and protect the electrical appliances from the superior.
What is the target of current protection of intelligent power distribution system?
1) overcurrent selective protection shall cover the entire low voltage distribution system, including the terminal distribution system。
2) to achieve selective protection in full current range, and selective protection can be achieved when the lower fault current reaches the superior transient current.
3) selective protection (within 200ms) is achieved in a very short period of time.
4) the condition that the system shorted the short circuit at the same time, or the lower and lower circuit breaker simultaneously. Ensure that power failure is limited to a minimum range.
In order to achieve full range and full current selective protection, the following technologies need to be solved:
(1) full range, all-current selective protection for overall solution research
(2) study on selective protection of regional interlocking
(3) all-current selective protection technology for universal circuit breakers
(4) study on the selective protection of plastic shell circuit breakers
4. Smart grid overvoltage protection technology because of the smart grid in a large number of the network, information technology and related equipment, these devices contained a large number of electronic devices, quite a number of equipment itself is electronic. They are vulnerable to lightning and other switching devices in the system. In addition, the new smart grid must include distributed energy system, these systems both in generating equipment and control equipment is also vulnerable to overvoltage damage, smart grid, overvoltage protection is particularly important, therefore, the key technology of it involves mainly has the following several aspects.
1) smart grid SPD configuration technology (overall solution)。
2) research on the structure and performance of SPD products for smart grid.
3) smart grid USES security research with SPD.
4) research on smart grid with SPD combinatorial technology.