Control system for flow of turbined water from a plurality of hydroelectric plants

Patent metadata

Field	Value
Publication number	US-10119518-B2
Application number	US-201515537844-A
Country	US
Kind code	B2
Filing date	Dec 22, 2015
Priority date	Dec 22, 2014
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A system for controlling the flow of turbined water from a plurality of hydroelectric plants arranged in series along a watercourse with an open channel flow, defining upstream of each plant, a plurality of head races subject respectively to hydraulic flow and level constraints. The flow of water turbined by each of the plants is controlled by a flow setpoint. The system includes regulation of a global electrical production power set-point for the plurality of hydroelectric plants by a flow regulation setpoint taking into account the flow setpoint of each of the plants. The flow regulation setpoint determined by the regulation is weighted for each of the plants by weighting coefficients as a function of the respective hydraulic characteristics of the head plurality of races.

First claim

The invention claimed is:

1. A system for driving a turbined water flow rate of a plurality of hydroelectric plants arranged in series along a watercourse with an open channel flow, defining upstream of each of the hydroelectric plants a plurality of respective reaches subjected to hydraulic flow rate and level requirements, said plurality of hydroelectric plants comprising at least three hydroelectric plants, wherein the turbined water flow rate for each of said plants is controlled by means of a flow rate setpoint on said plant determined from a run-of-the-river flow rate setpoint taking into account a level regulation of the reaches and the inflow rates in said reaches,
wherein the system comprises a regulation of an overall power output setpoint for said plurality of hydroelectric plants by means of a regulation flow rate setpoint taken into account by the flow rate setpoint of each of said plants and in that said regulation flow rate setpoint determined by said regulation is weighted for each of said plants by means of weighting coefficients as a function of the respective flow rate and level hydraulic requirements of the reaches defined upstream of said plants in order to meet said flow rate and level hydraulic requirements.

2. The system according to claim 1 , wherein the overall power output setpoint corresponds to the sum of a power setpoint of a power program and a balancing power for the power grid to which the plurality of plants is connected.

3. The system according to claim 1 , wherein the regulation of the overall power produced by the plurality of hydroelectric plants to meet an overall power output setpoint controls an overall effective power setpoint corresponding to the sum of the effective power setpoints of each plant, the effective power setpoints of each plant being determined by means of the flow rate setpoint of each of said plants.

4. The system according to claim 1 , wherein the weighting coefficients α i are dynamic and vary over time.

5. The system according to claim 4 , wherein a sum of the weighting coefficients α i applied to the power regulation flow rate setpoint of the plants except for the last plant is equal to the number n of the plants:

∑

i
=
1

n
-
1

⁢

α
i

=

n
.

6. The system according to claim 4 , wherein each of the weighting coefficients α i is determined by minimizing a criterion corresponding to an equation involving the weighting coefficient α i to be determined and the weighting coefficient α i−1 applied to the immediately upstream plant, the weighting coefficient α 1 of the first plant upstream of the queue being fixed.

7. The system according to claim 4 , wherein the weighting coefficients α i are determined by taking into account a level deviation between a nominal level setpoint of the reach i and a prediction of the level of said reach i at an optimisation horizon.

8. The system according to claim 7 , wherein taking into account the level deviation takes into account the weighting coefficient α i associated with a plant and the weighting α i−1 associated with the plant immediately upstream of said plant in a linear relationship corresponding to said level deviation.

9. The system according to claim 1 , wherein the weighting coefficients α i are constant over time.

10. The system according to claim 9 , wherein for m most upstream plants of the queue, with m≥1, the weighting coefficient α i of a plant is higher than a weighting coefficient α i−1 of the plant immediately upstream of said plant:
α i−1 <α i ,

and for n-r most downstream plants of the queue, with r≥1 and n the number of plants, the weighting coefficient α i of a plant is lower than the weighting coefficient α i−1 of the plant immediately upstream of said plant:
α i−1 >α i .

11. The system according to claim 9 , wherein determining a coefficient α i takes into account for m most upstream plants of the queue with m≥1 (respectively for n-r most downstream plants of the queue with r≥1 and n the number of plants), a ratio of a permitted volume variation for the reach i and a permitted volume variation for the first upstream reach (respectively for the last downstream reach).

12. The system according to claim 9 , wherein for m most upstream plants of the queue, with m≥1 (respectively for n-r most downstream plants of the queue, with r≥1 and n the number of plants), the weighting coefficient α i of a plant is determined as a function of the weighting coefficient α i−1 of the plant immediately upstream of said plant and the ratio of a permitted volume variation for the reach i to a permitted volume variation for the first upstream reach (respectively for the last downstream reach), said ratio being weighted by the weighting coefficient associated with the first upstream reach (respectively by the weighting coefficient associated with the next-to-last downstream reach),
whereas for the n-r-m plants between said most upstream plants of the queue and said n-r most downstream plants of the queue, the weighting coefficient corresponds to a same maximum value.

13. A plurality of hydroelectric plants arranged in series along a watercourse with an open channel flow, defining upstream of each of hydroelectric plants a plurality of respective reaches, said plurality of hydroelectric plants comprising at least three hydroelectric plants, and comprising a system for driving a turbined water flow rate according to claim 1 , wherein the turbined water flow rate for each of said plants is controlled by means of a flow rate setpoint on said plant determined from a run-of-the-river flow rate setpoint taking into account a level regulation of the reaches and the inflow rates in said reaches,
wherein the system comprises a regulation of an overall power output setpoint for said plurality of hydroelectric plants by means of a regulation flow rate setpoint taken into account by the flow rate setpoint of each of said plants and in that said regulation flow rate setpoint determined by said regulation is weighted for each of said plants by means of weighting coefficients as a function of the respective flow rate and level hydraulic requirements of the reaches defined upstream of said plants in order to meet said flow rate and level hydraulic requirements.

Assignees

• Electricite De France

Inventors

• Deprugney Luc
• Zarate Jennifer
• Robert Gerard

Classifications

• F03B17/06

  using liquid flow {with predominantly kinetic energy conversion}, e.g. of swinging-flap type {, "run-of-river", "ultra-low head" (F03B13/264 takes precedence)} · CPC title

• F03B15/14 Primary

  by or of water level · CPC title

• F03B15/16

  by power output · CPC title

• F05B2240/40

  Use of a multiplicity of similar components · CPC title

• E02B9/02

  Water-ways · CPC title