A wind power plant with reduced losses
US-2017234299-A1 · Aug 17, 2017 · US
Low-frequency band suppression enhanced anti-reversal power system stabilizer
US9906177B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-9906177-B2 |
| Application number | US-201615097691-A |
| Country | US |
| Kind code | B2 |
| Filing date | Apr 13, 2016 |
| Priority date | May 7, 2015 |
| Publication date | Feb 27, 2018 |
| Grant date | Feb 27, 2018 |
How to read this patent
A practical reading order for non-experts. Skip the full description unless you need deep technical detail.
- Title
What the patent document calls the invention.
- Abstract
A short plain-language summary of the technical disclosure.
- Assignees and inventors
Who owns or filed the patent and who is credited as inventor.
- Key dates
Filing, priority, publication, and grant dates set the timeline.
- First independent claim
The legal scope of protection — read this for what is actually claimed.
- CPC / IPC classifications
Technology tags used to group this patent with similar filings.
- Citations and related patents
Prior art links and similar publications in this corpus.
Abstract
Official abstract text for this publication.
A low-frequency band suppression enhanced anti-reversal power system stabilizer is presented by the invention. Currently the widely used PSS2B power system stabilizer needs lead elements above Order 2 to meet the phase compensation requirement of DC blocking signal of active power, thus quickly increasing high-frequency band gain, restricting allowable total setting gain of PSS, limiting low-band gain and reducing low-frequency band suppression ability of power system stabilizer. The invention will add generator speed signal ω (which is treated by DC blocking element and corrected by parallel proportional differential PD) and active power signal P e (which is treated by DC blocking element and gained by gain factor K s3 ) to get equivalent synthetic mechanical power of power system stabilizer. The actual active power signal gained by gain factor K S1 can meet the requirement of phase compensation through Order 1 lead and lag elements, thus increasing allowable total setting gain of PSS and improving the ability of low-frequency band oscillation suppression.
First claim
Opening claim text (preview).
What is claimed is: 1. A method of suppressing low frequency active power oscillation with minimum reactive power variation for super-large power grids comprising the steps of: step 1: check generator speed signal ω, use two-order DC blocking element to get speed fluctuation signal, which is corrected by parallel proportional differential PD to get corrected speed fluctuation signal; step 2: check active power signal of generator P e , and use 1st order or 2nd order DC blocking element to get fluctuation signal of active power, which is gained by gain factor K s3 to get gained fluctuation signal of active power; step 3: the gained fluctuation signal of active power in the step 2 is added with the corrected speed fluctuation signal in the step 1 together to become an equivalent synthetic mechanical power for equaling stationary mechanical power from prime mover; step 4: use notching filter to conduct lowpass filtering for the equivalent synthetic mechanical power gotten in the step 3 to get a lowpass filtered signal; step 5: subtract the fluctuation signal of active power in the step 2 from the lowpass filtered signal in the step 4 to get an actual fluctuation signal of active power; step 6: the actual fluctuation signal of active power in the step 5 is gained by gain factor K s1 , then is amended by 1st order lead or lag phase correction respectively and then is limited by upper limit and lower limit to get a final voltage signal suppressing fluctuation signal of active power, which is input to the super-large power grids by a power system stabilizer. 2. The method according to claims 1 , wherein a formula of the speed fluctuation signal in the step 1 is ω × s T w 1 1 + s T w 1 × s T w 2 1 + s T w 2 , in which T w1 , T w2 and s mean 1st order DC blocking time constant of speed signal, 2 nd order DC blocking time constant of speed signal and differential operator respectively; a formula of the parallel proportional differential PD correction is K w ×(1+ sT 7 ), in which K w , T 7 and s mean total proportional amplification factor of correction element, differentiating time constant and differential operator respectively. 3. The method according to claims 2 , wherein when obtaining the fluctuation signal of active power in the step 2, a formula is P e × s T w 3 1 + s T w 3 × s T w 4 1 + s T w 4 , in which T w3 , T w4 and s mean 1st order DC blocking time constant of active power, 2nd order DC blocking time constant of active power and differential operator respectively. 4. The method according to claims 3 , wherein a formula of the equivalent synthetic mechanical power in the step 3 is ω × s
Assignees
Inventors
Classifications
- H02P9/102Primary
for limiting effects of transients · CPC title
- H02J3/0014Primary
for preventing or reducing power oscillations in networks · CPC title
Patent family
Related publications grouped by family.
External sources
Frequently asked questions
Answers are generated from the same data shown on this page.
- What does patent US9906177B2 cover?
- A low-frequency band suppression enhanced anti-reversal power system stabilizer is presented by the invention. Currently the widely used PSS2B power system stabilizer needs lead elements above Order 2 to meet the phase compensation requirement of DC blocking signal of active power, thus quickly increasing high-frequency band gain, restricting allowable total setting gain of PSS, limiting low-ba…
- Who is the assignee on this patent?
- State Grid Zhejiang Electric Power Res Institute, State Grid Corp China, Nr Electric Co Ltd
- What technology area does this patent fall under?
- Primary CPC classification H02P9/102. Mapped technology areas include Electricity.
- When was this patent published?
- Publication date Tue Feb 27 2018 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 12 related publications on this page (citations in our corpus or others sharing the same primary CPC).