Method for detecting power failure of power grid for three-phase uninterruptable power supply

A technology of power failure detection and three-phase power grid, which is applied in the direction of fault location, etc., can solve the problems of not being able to judge whether the power grid is powered off in time, it is difficult to do fast detection, and increase the time of power failure detection, so as to achieve rapid detection, accumulation and The effect of large value and fixed detection time

Active Publication Date: 2011-07-06
海亿新能源扬州有限公司
View PDF6 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The detection time is fixed, but it is difficult to achieve fast detection. The detection time of this method is greater than 4ms
Moreover, when the input of the UPS is connected to the generator, since the waveform of the generator is very poor, in order to identify the waveform of the generator, a very complicated algorithm is required, or by increasing the power-off detection time to judge whether the power is off, so that it is impossible to judge whether the power grid is in time power down

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for detecting power failure of power grid for three-phase uninterruptable power supply
  • Method for detecting power failure of power grid for three-phase uninterruptable power supply
  • Method for detecting power failure of power grid for three-phase uninterruptable power supply

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0044] The present invention will be further described below in conjunction with the accompanying drawings.

[0045] Such as figure 2 As shown, the power grid power failure detection method of the three-phase uninterruptible power supply includes the following steps:

[0046] A: The cycle interrupt is started, and the processor samples the full-wave rectified three-phase grid voltage signal in real time;

[0047] B: Accumulate and sum the sampled three-phase instantaneous voltage values;

[0048] C: Determine whether the accumulated sum is less than the set power-off detection point 1000, if the accumulated sum of the three-phase instantaneous voltage values ​​is less than the set power-off detection point 1000, then execute step G; if the accumulated sum of the three-phase instantaneous voltage values ​​is greater than or equal to 1000, then execute step D;

[0049] D: Determine whether the instantaneous low voltage flag is 1, if not, execute step F; if the instantaneous ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to the field of an alternated current inverter, in particular to a method for detecting power failure of a power grid for a three-phase uninterruptable power supply. The method comprises the following steps: sampling a full-wave rectified three-phase power grid voltage at real time; sampling for 180 times in a power frequency period; judging if the accumulation of the three-phase instantaneous voltage at each time is lower than a preset power failure detection point; and if the three-phase input voltage of UPS (uninterruptable power supply) is low-voltage and abnormal for 2ms, confirming that the power grid is in power failure. By utilizing the characteristic of three-phase power grid that the accumulation of the absolute values of the three-phase instantaneous voltages at any moment is in the scope of 1.732-2 times of peak voltages, the method can be used for accurately and quickly detecting the three-phase power failure. The detection time is stable and the system reliability is strong.

Description

technical field [0001] The invention relates to the field of AC inverter power supplies, in particular to a power-off detection method for a power grid of a three-phase uninterruptible power supply. Background technique [0002] The backup UPS is usually in the charging state of the battery. When the power grid fails, the inverter switches to the working state urgently, converting the DC power provided by the battery into a stable AC output. Therefore, the backup UPS has a switching time problem. How to quickly and accurately detect the power failure of the power grid is the core technology and difficulty of the backup UPS. Because if the detection time is too long, it will inevitably cause the load equipment to stop working, which means that the UPS does not work. If the detection is fast, it is easy to malfunction, resulting in frequent switching between the mains and the inverter, resulting in damage to the UPS. At present, the grid power failure detection method of the ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01R31/08
Inventor 王美力
Owner 海亿新能源扬州有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap