Thermal power unit-flywheel energy storage cooperative frequency regulation control method and system

Patent metadata

Field	Value
Publication number	US-12136818-B2
Application number	US-202318334153-A
Country	US
Kind code	B2
Filing date	Jun 13, 2023
Priority date	Jun 14, 2022
Publication date	Nov 5, 2024
Grant date	Nov 5, 2024

Abstract

A thermal power unit-flywheel energy storage cooperative frequency regulation control method and system is provided, which belongs to the technical field of a power grid. First, a real-time output increment of a thermal power unit is predicted, then a real-time frequency regulation power instruction of a flywheel energy storage system is determined based on the predicted real-time output increment of the thermal power unit, and finally the frequency regulation power instruction of the thermal power unit is determined by a difference adjustment coefficient of a governor and a grid frequency deviation. The thermal power unit and flywheel energy storage system is cooperatively controlled by frequency regulation based on the real-time output increment predicted value of the unit, which realizes self-adaptive adjustment of output of the flywheel energy storage system under dynamic working conditions, and improves the grid frequency stability and operation safety of the thermal power unit.

First claim

What is claimed is:

1. A thermal power unit-flywheel energy storage cooperative frequency regulation control method, comprising:
obtaining a real-time operating parameter of a thermal power unit, a difference adjustment coefficient of a governor, a grid frequency deviation, a current state of charge of an energy storage battery and a rated power of an energy storage system;
obtaining a predicted value of an output power increment of the thermal power unit by using a dynamic model of the thermal power unit according to the real-time operating parameter of the thermal power unit;
determining an initial power instruction of a flywheel energy storage system according to the predicted value of the output power increment of the thermal power unit, the difference adjustment coefficient of the governor and the grid frequency deviation;
obtaining a real-time maximum discharge power of the flywheel energy storage system by using a Logistic regression function according to the current state of charge of the energy storage battery and the rated power of the energy storage system;
selecting a minimum value between the real-time maximum discharge power of the flywheel energy storage system and the initial power instruction of the flywheel energy storage system as a real-time frequency regulation power instruction of the flywheel energy storage system, and sending it to the flywheel energy storage system;
determining a frequency regulation power instruction of the thermal power unit according to the difference adjustment coefficient of the governor and the grid frequency deviation, and sending it to the thermal power unit.

2. The method of claim 1 , wherein the obtaining a predicted value of an output power increment of the thermal power unit by using a dynamic model of the thermal power unit according to the real-time operating parameter of the thermal power unit, comprises:
building the dynamic model of the thermal power unit, wherein the dynamic model of the thermal power unit comprises a boiler dynamic model and a steam turbine dynamic model;
obtaining a predicted value of a main steam flow increment by using a formula

Δ
⁢

D
t

=

K
6

(

∫

u
t

⁢

dp
t

+

∫

p
t

⁢

du
t

)

=

K
6

⁢

∫

(

u
t

⁢

dp
t

dt

+

p
t

⁢

du
t

dt

)

⁢
dt

based on the boiler dynamic model and according to the real-time operating parameter of the thermal power unit, wherein ΔD t is the predicted value of the main steam flow increment at time t, K 6 is an internal balance coefficient of a simulation model, u t is a valve opening at time t, p t is a main steam pressure of the thermal power unit at time t;
inputting the predicted value of the main steam flow increment into the steam turbine dynamic model, and obtaining the predicted value of the output power increment of the thermal power unit by using a formula

Δ
⁢

N
p

=

1
+

s
⁢
λ
⁢

T
RH

⁢

F
HP

+

sT
RH

⁢

F
HP

(

1
+

sT
SC

)

⁢

(

1
+

sT
RH

)

⁢
Δ
⁢

D
t

,

Assignees

• Univ North China Electric Power

Inventors

• Hong Feng
• Liang Lu
• Jia Xinyi
• Hao Junhong
• Du Yanjun
• Wang Wei
• Fang Fang

Classifications

• H02J2103/30

  Simulating, planning, modelling, reliability check or computer assisted design [CAD] of electric power networks · CPC title

• H02J3/0014 Primary

  for preventing or reducing power oscillations in networks · CPC title

• H02J15/30

  using storage of inertial or mechanical energy, e.g. using flywheels · CPC title

• H02J3/00142

  Oscillations concerning frequency · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title