Current pattern matching method for non-intrusive power load monitoring and disaggregation

Patent metadata

Field	Value
Publication number	US-9658261-B2
Application number	US-201314442725-A
Country	US
Kind code	B2
Filing date	Nov 8, 2013
Priority date	Nov 16, 2012
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A harmonic-characteristics based current pattern matching method for the non-intrusive power load monitoring and disaggregation is provided in this present invention, on the basis of establishing the load signature database, which comprises electrical appliance registration and load state word space initialization, data acquisition and data preprocessing, feasible state word space search based on table looking-up, the optimal matching of current pattern, and display and output of the monitoring and disaggregation results. The method improves the accuracy of disaggregation, and can achieves exact identification of operating states of appliances, and also can reduce the cost.

First claim

The invention claimed is:

1. A harmonic-characteristics based current pattern matching method performed with a monitor device for the non-intrusive power load monitoring, comprising steps:
(a) establishing a load signature database of household appliances, said database comprising information about (i) power states and operating states which each appliance of said various appliances has, and (ii) steady-state current harmonic parameters of each of said operating states of each said appliance;
(b) registering all electrical appliances inside a total household load and initializing a linear load state word space table in an on-board memory module of said monitor device by (i) acquiring load characteristic information for each of said electrical appliances from said load signature database and (ii) performing statistical analysis on all possible operating states of said total household load and storing results of said statistical analysis in said memory module in the form of a linear state word table;
(c) performing data acquisition and data preprocessing by measuring terminal voltage and steady-state total current of said household load, which are then processed in a processing module in said monitor device to obtain a measured total fundamental active power value, a total fundamental reactive power value and a unit total current pattern;
(d) performing a looking-up search on said linear state word table to obtain a feasible state word space based on said measured total fundamental active power value and said total fundamental reactive power value;
(e) performing an optimal matching of current pattern based on the following equation:

min

∀

SW
k

∈

Ω
sw

⁡

(

P
l
1

⁡

(
t
)

,

Q
l
1

⁡

(
t
)

)

⁢



I
l

⁡

(

P
l
1

⁡

(
t
)

,

Q
l
1

⁡

(
t
)

)

-

I
^

l

⁡

(

SW
k

,

U
1

)



2

to obtain conresponding SW min (t) and P 1 min (t) values in said feasible state word space and, by disaggregating said total fundamental active power value based on said SW min (t) and P 1 min (t) values, to obtain the information of the power state and operating state for each of said electrical appliances inside said household load at the given point of time when terminal voltage and steady-state total current of said household load are measured; and
(f) displaying said information of the power state and operating state on a screen of said monitor device;
wherein in step (a) said steady-state current harmonic parameters in step (a) is determined based on the following equation:

H
ai

=

[

1
⁢

∠θ

1
,
1

…

1

Assignees

• Univ Tianjin

Inventors

• Yu Yixin
• Liu Bo
• Wang Bing

Classifications

• H02J3/0014 Primary

  for preventing or reducing power oscillations in networks · CPC title

• H02J3/24

  Electricity · mapped topic

• G01R21/133

  by using digital technique · CPC title

• G01R19/2513

  Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging · CPC title

• G01R23/00

  Arrangements for measuring frequencies; Arrangements for analysing frequency spectra · CPC title