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US-12620917-B2 - Water turbine power generation system and control method for providing improved dynamic response to major power setpoint variations

US12620917B2US 12620917 B2US12620917 B2US 12620917B2US-12620917-B2

Abstract

The invention relates to a method for controlling an energy production system ( 1 ), comprising: —a connecting link ( 6 ) provided with a connection ( 62 ) to an AC network ( 2 ); —a turbine system ( 3 ) comprising an electric machine ( 31 ) for delivering a nominal electrical power Pnom; —an energy storage system ( 14 ), comprising the following steps; —receipt of a first electrical power setpoint Ps0 and control of the turbine system ( 3 ) so as to deliver an electrical power Pt0=Ps0; and—receipt of an electrical power setpoint Ps1, where ΔPs=Ps1−Ps0 and |ΔPs|>Pnom*0.3; a) application of a hydraulic setpoint to the turbine system ( 3 ) so as to increase the delivered electrical power Pti thereof and prevent the storage system ( 14 ) from delivering electrical power ( 62 ); b) determination of the power Pea that the storage system ( 14 ) is able to supply; c) when Pti+Pea≥Ps1−ε1, the storage system ( 14 ) delivers an electrical power Pe1 to satisfy the requirement Ps1−ε1≤Pe1+Pti≤Ps1+ε2.

Inventors

  • Renaud GUILLAUME
  • Hugo MESNAGE

Assignees

  • SUPERGRID INSTITUTE

Dates

Publication Date
20260505
Application Date
20220131
Priority Date
20210201

Claims (20)

  1. 1 . A method of controlling an electricity generation system ( 1 ) comprising: a feeder link ( 6 ) comprising a connection interface ( 62 ) for connection to an AC grid ( 2 ); a turbine system ( 3 ) comprising an electrical machine ( 31 ) and configured to deliver a nominal electrical power Pnom to the feeder link ( 6 ); an energy storage system ( 14 ) connected to the feeder link ( 6 ), wherein the control method comprises the following steps: receiving from the AC grid ( 2 ) a first electrical power setpoint Ps0 to be delivered to the connection interface ( 62 ) and controlling the turbine system ( 3 ) so as to deliver an electrical power Pt0=Ps0 to the connection interface; and receiving another electrical power setpoint Ps1 from the AC grid ( 2 ), where a variation in electrical power ΔPs=Ps1−Ps0 and |ΔPs|>Pnom*0.3; if Ps 1> Ps 0: a) applying a hydraulic setpoint to the turbine system ( 3 ) to increase its electrical power output Pti and prevent the energy storage system ( 14 ) from supplying electrical power to the connection interface ( 62 ); b) determining a power Poa that the energy storage system 14 can supply to the connection interface; c) when Pti+a power supported by electrical storage system Pea≥Ps1−a lower power deviation ε1, control of the energy storage system ( 14 ) in order to supply an electrical power Pel to the connection interface with a view to fulfilling a requirement Ps1−the lower power deviation ε1≤Pe1+Pti≤Ps1+a upper power deviation ε2, with the lower power deviations ε1 and the upper power deviation ε2 tolerated by the AC grid ( 2 ) at the connection interface ( 62 ); or if Ps0>Ps1: n) applying the hydraulic setpoint to the turbine system in order to decrease its electrical power output Pti and prevent the energy storage system ( 14 ) from retrieving electrical power from the connection interface; o) determining the power Pea that the energy storage system ( 14 ) can retrieve from the connection interface ( 62 ); p) when Pti+Pea≤Ps1+ε2, controlling the energy storage system ( 14 ) to retrieve electrical power Pe1 from the connection interface with a view to fulfilling the requirement Ps 1−ε1≤ Pe 1+ Pti≤Ps 1+ε2.
  2. 2 . The control method according to claim 1 , wherein ε1≤0.02*Pnom and 82≤0.02*Pnom.
  3. 3 . The control method according to claim 1 , wherein a completion signal is sent to a system for managing the AC grid ( 2 ) when the requirement Ps 1−ε1≤ Pe 1+ Pti≤Ps 1+82 is fulfilled.
  4. 4 . The control method according to claim 1 , wherein the hydraulic setpoint is applied to the turbine system to cause it to deliver electrical power Pti transiently to the connection interface when the requirement Ps 1−ε1≤ Pe 1+ Pti≤Ps 1+ε2 is fulfilled, where: Pti>Ps 1 if Ps 1> Ps 0; or Pti<Ps 1 if Ps 0> Ps 1.
  5. 5 . The control method according to claim 4 , wherein, when the requirement Ps1−ε1≤Pe1+Pti≤Ps1+ε2 is fulfilled, the electrical power Pti transiently satisfies the relationship: Pti>Ps 1+0.1*Pnom if Ps 1> Ps 0; or Pti<Ps 1-0.1*Pnom if Ps 0> Ps 1.
  6. 6 . The control method according to claim 4 , wherein the energy storage system ( 14 ) is controlled to sequentially absorb and supply electrical power to the connection interface when the requirement Ps1−ε1≤Pe1+Pti≤Ps1+ε2 is fulfilled.
  7. 7 . The control method according to claim 1 , wherein: Pe1=0 between the time at which the another electrical power setpoint Ps1 is received and the time at which Pti+Pea−ε1≥Ps1 or between the time at which the setpoint Ps1 is received and the time at which Pti+Pea+ε2≤Ps1.
  8. 8 . The control method according to claim 1 , wherein, between the moment at which the another electrical power setpoint Ps1 is received and the moment at which Pti+Pea− ε1≥ Ps 1,the energy storage system is controlled to: apply Pe 1<0 if Ps 1> Ps 0; or apply Pe 1>0 if Ps 0> Ps 1.
  9. 9 . A power generation system ( 1 ), characterised in that it comprises: a feeder link ( 6 ) comprising a connection interface ( 62 ) for connection to an AC grid ( 2 ); a turbine system ( 3 ) comprising an electrical machine ( 31 ) and configured to deliver a nominal electrical power Pnom to the feeder link ( 6 ); an energy storage system ( 14 ) connected to the feeder link ( 6 ); a control system ( 7 ) configured to control the operation of the power generation system ( 1 ), wherein the control system ( 7 ) is configured for: receiving from the AC grid ( 2 ) a first electrical power setpoint Ps0 to be delivered to the connection interface ( 62 ) and controlling the turbine system ( 3 ) to deliver an electrical power Pt0=Ps0 to the connection interface; and receiving another electrical power setpoint Ps1 from the AC grid ( 2 ), where variation in electrical power ΔPs=Ps1−Ps0 and |ΔPs|>Pnom*0.3; if Ps 1> Ps 0: a) applying a hydraulic setpoint to the turbine system ( 3 ) to increase its electrical power output Pti and prevent the energy storage system ( 14 ) from supplying electrical power to the connection interface ( 62 ); b) determining a power Pea that the energy storage system 14 can supply to the connection interface; c) when Pti+a power supported by electrical storage system Pea≥Ps1−a lower power deviation ε1, controlling the energy storage system ( 14 ) to deliver electrical power Pe1 to the connection interface to fulfil a requirement Ps1−the lower power deviation ε1≤Pe1+Pti≤Ps1+an upper power deviation ε2, with the lower power deviation ε1 and the upper power deviation ε2 tolerated by the AC grid ( 2 ) at the connection interface ( 62 ); or if Ps 0> Ps 1: n) applying the hydraulic setpoint to the turbine system in order to decrease its electrical power output Pti and prevent the energy storage system ( 14 ) from retrieving electrical power from the connection interface; o) determining the power Pea that the energy storage system ( 14 ) can retrieve from the connection interface ( 62 ); p) when Pti+Pea≤Ps1+ε2, controlling the energy storage system ( 14 ) to retrieve electrical power Pe1 from the connection interface with a view to fulfilling the requirement Ps 1−ε1≤ Pe 1+ Pti≤Ps 1+ε2.
  10. 10 . The power generation system ( 1 ) according to claim 9 , wherein the energy storage system ( 14 ) comprises a direct current electrical transducer ( 13 ), an AC/DC converter ( 12 ) having an AC interface connected to the feeder link ( 6 ) and a DC interface connected to the direct current electrical transducer ( 13 ).
  11. 11 . The power generation system ( 1 ) according to claim 10 , wherein the energy storage system ( 14 ) comprises a DC/DC converter ( 131 ) configured to change a voltage level between a DC electrical transducer ( 132 ) and the AC/DC converter ( 12 ).
  12. 12 . The power generation system ( 1 ) according to claim 11 , wherein the DC electrical transducer ( 13 ) is selected from the group comprising a supercapacitor, a fuel cell, an electrochemical battery, an electric motor driving a flywheel, an air compressor and an electromagnetic storage.
  13. 13 . The power generation system ( 1 ) according to claim 9 , wherein Pe1>Pea/2.
  14. 14 . A method of controlling an electricity generation system ( 1 ) comprising: a feeder link ( 6 ) comprising a connection interface ( 62 ) for connection to an AC grid ( 2 ); a turbine system ( 3 ) comprising an electrical machine ( 31 ), a turbine ( 32 ) and a turbine controller ( 9 ), wherein the turbine controller is configured to deliver at least one fluid parameter setpoint to the turbine ( 32 ) influencing the electrical power delivered by the electrical machine ( 31 ), wherein the electrical machine ( 31 ) delivers an instantaneous electrical power Ph to the connection link ( 6 ); an energy storage system ( 14 ) connected to the feeder link ( 6 ); wherein the control method includes the following steps: a) receiving a first electrical power setpoint Ps0 to be delivered to the connection interface ( 62 ) and controlling the turbine system ( 3 ) so as to deliver an electrical power Ph=Ps0 to the connection interface; and b) receiving a subsequent electrical power setpoint Ps1 ( 2 ), where variation in electrical power ΔPs=Ps1−Ps0, where Ps1>Ps0; c) based on a predictive control model of the electrical power generated by the turbine system ( 3 ), determining successive operating parameters of the turbine controller ( 9 ) so that the Ph reaches Ps1 with a minimum amount of additional energy; d) until Ph=Ps1, applying electrical power Pb to the feeder link ( 6 ) by means of the energy storage system ( 14 ), where Pb+Ph=Ps1, and applying the successive operating parameters to the turbine controller ( 9 ).
  15. 15 . The method of controlling an electricity generation system ( 1 ) according to claim 14 , wherein the energy storage system ( 14 ) has an instantaneous available energy Eess, the method furthermore comprising determination of an additional energy Emin that the electrical power system ( 14 ) must supply to the connection link ( 6 ) in order to fulfil the condition Ps1=Pb+Ph until Ph=Ps1, wherein step d) is triggered only when Eess>Emin.
  16. 16 . The method of controlling an electricity generation system ( 1 ) according to claim 14 , wherein step d) is triggered less than 5 seconds after step b).
  17. 17 . The method of controlling an electricity generation system ( 1 ) according to claim 16 , wherein step d) is triggered less than 1 second after step b).
  18. 18 . The method of controlling an electricity generation system ( 1 ) according to claim 14 , wherein the successive operating parameters are the turbine operating points, wherein step c) is performed by iteratively evaluating the instantaneous power Ph, by comparing the evaluated instantaneous power Ph with the electrical power anticipated by the model predictive control, determining updated successive operating parameters for the turbine controller ( 9 ) so that Ph reaches Ps1 with a minimum amount of additional energy.
  19. 19 . The method of controlling an electricity generation system ( 1 ) according to claim 14 , wherein the turbine controller ( 9 ) is a PID controller, the successive operating parameters being successive values of at least one gain variable selected from a proportional gain, an integration gain and a derivative gain.
  20. 20 . The method of controlling an electricity generation system ( 1 ) according to claim 14 , wherein said turbine ( 32 ) is a water turbine, and wherein said fluid parameter setpoint is a guide valve opening setpoint of the water turbine ( 32 ).

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a national stage entry of and claims the benefit of International Application Serial No. PCT/EP2022/052233, titled “Water turbine power generation system and control method for providing improved dynamic response to major power setpoint variations,” filed by SUPERGRID INSTITUTE on Jan. 31, 2022, which application claims the benefit of French Application Serial No. FR2100947, filed on Feb. 1, 2021, and of French Application Serial No. FR2200640, filed on Jan. 25, 2022. This application incorporates the entire contents of the foregoing application(s) herein by reference. The invention relates to a monitoring strategy for optimising the operation of a hybrid power generation system using a turbine system generating electrical power to an alternating current grid (AC grid), as a primary source of power, and an energy storage system, as a secondary source. The invention relates in particular to the management of significant variations in the electrical power setpoint. The invention also relates to the management of sudden variations in the electrical power setpoint Many electric power plants, particularly hydroelectric dams, include a turbine system for generating electrical power that is transferred to an AC grid via a feeder link. Significant variations in electrical power may be requested by the AC grid manager from the power generation system. Due to its physical limitations, the turbine system cannot deliver a significant variation in electrical power output instantaneously. For example, the responsiveness of a hydraulic system to a significant variation in the power setpoint is generally greater than 30 seconds, particularly given the inertia of the water column in the upstream pipes connected to the turbine. A water turbine system is configured to operate over a specific output power range. Outside this output power range, several undesirable phenomena can be expected. For example, with a Francis turbine, an instability of the system called “S-shape” appears for an output power between 0% and 20% of the nominal output power, an unstable vortex appears between the turbine blades for an output power between 20% and 40% of the nominal output power, a helical vortex may appear downstream of the turbine for an output power between 40% and 60% of the nominal output power and a straight vortex downstream of the turbine may appear for an output power between 90 and 110% of the nominal output power. These undesirable phenomena are known to damage parts of the turbine system and prolonged use of the system under these conditions forces operators to repair the damaged parts, resulting in increased system interruptions for maintenance and, consequently, increased maintenance costs. The hydraulic system may be associated with an energy storage system connected to the feeder link to increase the responsiveness of the turbine system to a new electrical power setpoint provided by an AC grid operator. A control circuit receives an electrical power setpoint sent by the AC grid manager and, based on this setpoint, controls a transient power transfer between the feeder link and the energy storage system by selectively controlling the charging or discharging of the energy storage system. When a new setpoint is received, the energy storage system contributes to this variation by immediately participating in the power variation with the turbine. However, given its cost, the energy storage system has a limited capacity. As a result, it can only contribute to a limited variation in electrical power after a new electrical power setpoint has been transmitted by the AC grid operator. As a result, the actual electrical power supplied to the AC grid does not reach the setpoint requested by the AC grid operator quickly enough. Indeed, responsiveness to a variation in power setpoint has an increasing market value within the context of integrating more renewable energies into electricity grids. This market value increases the profitability of the turbine system, if this responsiveness can be improved. It is therefore necessary to improve the responsiveness of a power generation system using a turbine system in order to respond to a new electrical power setpoint involving a significant power variation. On the other hand, electrical power suppliers can derive revenue from system operator requirements. These needs are defined in the form of requests to supply energy to a grid, requests which sometimes require very short activation times, typically less than 1 sec. Such power requests can be made in order to compensate for the difference between production and consumption at the grid level. Such services can generate significant revenue for electricity suppliers if these output power adjustment times are adhered to. The hydraulic system may be associated with an energy storage system to increase the responsiveness of the turbine system when a new electrical power setpoint is applied