Unlock instant, AI-driven research and patent intelligence for your innovation.

Method, device and equipment for detecting DC voltage of cascaded h-bridge power module

A technology of power module and DC voltage, applied in the field of electric power, can solve the problems of difficult application of high-voltage system, increase of calculation time, calculation accuracy is greatly affected by the number of power modules and sampling accuracy, etc., and achieves the effect of wide applicability

Active Publication Date: 2022-03-25
NANCHANG INST OF TECH
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Among the existing technologies, the DC voltage of the cascaded H-bridge power module is generally detected indirectly based on the potential transformer (PT) on the commutation chain. However, when there are many power modules, the PT sampling error will cause a large detection error, and if the number of power modules increases, the calculation time will increase rapidly, resulting in a large delay
Therefore, the calculation accuracy of existing indirect detection methods is greatly affected by the number of power modules and sampling accuracy, and it is difficult to apply to high-voltage systems

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, device and equipment for detecting DC voltage of cascaded h-bridge power module
  • Method, device and equipment for detecting DC voltage of cascaded h-bridge power module
  • Method, device and equipment for detecting DC voltage of cascaded h-bridge power module

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0102] see image 3 , shows the method for detecting the DC voltage of the cascaded H-bridge power module in the first embodiment of the present invention, and the method specifically includes step S01-step S04.

[0103] Step S01, obtaining the AC current of the commutation chain collected by the current transformer on the commutation chain of the cascaded H-bridge, and obtaining the current stage of the power module on the commutation chain.

[0104] Among them, such as figure 2 As shown in , it shows the arrangement position diagram of the current transformer (CT for short) on the commutation chain, which is different from the arrangement position of the traditional PT. The current stage of the power module includes the non-control stage and the control stage. In the specific implementation, the current transformer will sample the AC current of the commutation chain every preset time, and the preset time is the calculation step size ΔT. Every time the AC current of the co...

Embodiment 2

[0132] see Figure 6 , shows the method for detecting the DC voltage of the cascaded H-bridge power module in the second embodiment of the present invention, and the method specifically includes step S11-step S16.

[0133] Step S11, obtaining the AC current of the commutation chain collected by the current transformer on the commutation chain of the cascaded H-bridge, and obtaining the current stage of the power module on the commutation chain.

[0134] Step S12, when the power module is in the non-controlling phase, calculate the DC current of the power module according to the AC current of the commutation chain.

[0135] Step S13, when the power module is in the control phase, obtain the switch state matrix of each switch of the power module, and calculate the DC current of the power module according to the switch state matrix and the AC current of the commutation chain current.

[0136]Step S14, calculating the DC voltage of the power module according to the DC current of...

Embodiment 3

[0174] Another aspect of the present invention also provides a cascaded H-bridge power module DC voltage detection device, please refer to Figure 15 , shows the detection device for the DC voltage of the cascaded H-bridge power module in the third embodiment of the present invention, and the device includes:

[0175] The information acquisition module 11 is configured to acquire the AC current of the commutation chain collected by the current transformer arranged on the commutation chain of the cascaded H-bridge, and obtain the current stage of the power module on the commutation chain;

[0176] The current calculation module 12 is used to calculate the DC current of the power module according to the AC current of the commutation chain when the power module is in the non-control phase; when the power module is in the control phase, obtain the a switch state matrix of each switch of the power module, and calculate the DC current of the power module according to the switch stat...

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 present invention provides a method, device and equipment for detecting the DC voltage of a cascaded H-bridge power module. The current stage of the power module on the commutation chain; when the power module is in the non-control stage, calculate the DC current of the power module according to the AC current of the commutation chain; The switch state matrix of the switch, and calculate the DC current of the power module according to the switch state matrix and the AC current of the commutation chain; calculate the DC voltage of the power module according to the DC current of the power module. The present invention proposes a new method for indirectly detecting the DC voltage of cascaded H-bridge power modules based on the AC current of the commutation chain. The calculation accuracy of the method has nothing to do with the number of power modules and is not affected by the number of power modules. It can be applied to high-voltage systems , with wider applicability.

Description

technical field [0001] The invention relates to the field of electric power technology, in particular to a method, device and equipment for detecting DC voltage of cascaded H-bridge power modules. Background technique [0002] Chained STATCOM is an advanced reactive power compensation equipment, which is widely used in power quality compensation of new energy power stations. Cascaded H-bridges are the most common structure for chained STATCOMs. Ensuring the stability of the DC voltage of each power module is a necessary condition for the operation of the device. Therefore, it is generally necessary to detect the DC voltage of the power module during specific operation. [0003] The traditional solution is often to install a DC voltage sensor on each power module, so the chained STATCOM often needs to install dozens of sensors. Adding sensors will increase equipment cost and bring additional measurement loss. And when a sensor of a certain power module fails, the entire de...

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 Patents(China)
IPC IPC(8): H02M1/00H02M7/00H02M7/5387G01R19/00
CPCH02M1/00H02M7/00H02M7/5387G01R19/00
Inventor 张扬李三苹盛敬许惠君饶繁星黄志开刘剑冰彭世健穆阳毛忠坤胡志文
Owner NANCHANG INST OF TECH