CN-122026448-A - Off-grid electrochemical system, control method of electrochemical system and power station

CN122026448ACN 122026448 ACN122026448 ACN 122026448ACN-122026448-A

Abstract

The disclosure relates to an off-grid electrochemical system, a control method of the electrochemical system and a power station, and relates to the technical field of new energy. The off-grid electrochemical system can realize power adjustment when the wide frequency of the power grid fluctuates. The system comprises a power generation subsystem, a hydrogen production subsystem, an energy storage subsystem and an energy management system, wherein the energy management system is respectively in communication connection with the power generation subsystem, the hydrogen production subsystem and the energy storage subsystem, the energy storage subsystem is used for determining ideal voltage and ideal angular frequency according to an active power preset value, a reactive power preset value, an energy storage three-phase voltage value and an energy storage three-phase current value and sending the ideal voltage and the ideal angular frequency to the energy management system, and the energy management system is used for controlling the power generation subsystem to assist the energy storage subsystem in power adjustment or controlling the hydrogen production subsystem to assist the energy storage subsystem in power adjustment according to the ideal voltage and the ideal angular frequency so as to balance the generated power and the used power of the off-grid electrochemical system.

Inventors

Mou Shujun
SUN XUN
XING XIAOWEN
WANG HONGGANG
ZHOU YOU

Assignees

国家能源投资集团有限责任公司
北京低碳清洁能源研究院

Dates

Publication Date: 20260512
Application Date: 20241101

Claims (12)

1. The off-grid electrochemical system is characterized by comprising a power generation subsystem, a hydrogen production subsystem, an energy storage subsystem and an energy management system, wherein the energy management system is respectively in communication connection with the power generation subsystem, the hydrogen production subsystem and the energy storage subsystem; The energy storage subsystem is used for determining ideal voltage and ideal angular frequency according to an active power preset value, a reactive power preset value, an energy storage three-phase voltage value and an energy storage three-phase current value and sending the ideal voltage and the ideal angular frequency to the energy management system; The energy management system is used for controlling the power generation subsystem to assist the energy storage subsystem in power adjustment or controlling the hydrogen production subsystem to assist the energy storage subsystem in power adjustment according to the ideal voltage and the ideal angular frequency so as to balance the generated power and the used power of the off-grid electrochemical system.
2. The off-grid electrochemical system of claim 1, wherein the energy management system is configured to generate a control instruction according to a relationship between the ideal angular frequency and upper and lower limits of a preset frequency interval, and send the control instruction to the power generation subsystem and the energy storage subsystem to control the power generation subsystem to assist the energy storage subsystem in power adjustment, or send the control instruction to the hydrogen production subsystem and the energy storage subsystem to control the hydrogen production subsystem to assist the energy storage subsystem in power adjustment.
3. The off-grid electrochemical system of claim 2, wherein the energy management system is configured to generate a first control command when the ideal angular frequency is greater than an upper limit of the preset frequency interval, and to send the first control command to the power generation subsystem and the energy storage subsystem, respectively, the first control command carrying the active power preset value, the reactive power preset value, the ideal voltage, and the ideal angular frequency.
4. The off-grid electrochemical system of claim 2, wherein the energy management system is configured to generate a second control command when the ideal angular frequency is less than a lower limit of the preset frequency interval, and send the second control command to the hydrogen production subsystem and the energy storage subsystem, respectively, the second control command carrying the active power preset value, the reactive power preset value, the ideal voltage, and the ideal angular frequency.
5. The off-grid electrochemical system of claim 3, wherein the energy storage subsystem comprises an energy storage controller, an energy storage battery, and an energy storage converter, and the power generation subsystem comprises a new energy controller, a new energy power generation device, and a new energy converter; The energy storage controller is used for receiving the first control instruction, obtaining a first pulse width modulation signal according to the ideal voltage and the ideal angular frequency, controlling the energy storage battery to discharge according to the ideal voltage, and controlling the energy storage converter to regulate the voltage frequency according to the first pulse width modulation signal; And the new energy controller is used for receiving the first control instruction, obtaining a second pulse width modulation signal according to the active power preset value, the reactive power preset value and the ideal angular frequency, controlling the power generation output power of the new energy power generation device according to the active power preset value, and controlling the new energy converter to perform voltage frequency adjustment according to the second pulse width modulation signal.
6. The off-grid electrochemical system of claim 5, wherein the new energy controller is configured to: performing amplitude limiting treatment on the generated output power of the new energy power generation device according to the active power preset value to obtain ideal generated output power; adjusting a first phase locking angle of the new energy converter according to the ideal angular frequency and the current voltage of the new energy power generation device to obtain a first angular frequency change rate; and sequentially performing voltage control loop processing and current control loop processing according to the ideal power generation output power, the reactive power preset value and the first angular frequency change rate to obtain the second pulse width modulation signal.
7. The off-grid electrochemical system of claim 4, wherein the energy storage subsystem comprises an energy storage controller, an energy storage battery, and an energy storage converter, and the hydrogen production subsystem comprises a hydrogen production controller, a hydrogen production electrolyzer, and a hydrogen production converter; The energy storage controller is used for receiving the second control instruction, obtaining a third pulse width modulation signal according to the ideal voltage and the ideal angular frequency, controlling the energy storage battery to charge according to the ideal voltage, and controlling the energy storage converter to regulate the voltage frequency according to the third pulse width modulation signal; And the hydrogen production controller is used for receiving the second control instruction, obtaining a fourth pulse width modulation signal according to the active power preset value, the reactive power preset value and the ideal angular frequency, controlling the hydrogen production output power of the hydrogen production electrolytic tank according to the active power preset value, and controlling the hydrogen production converter to carry out voltage frequency adjustment according to the fourth pulse width modulation signal.
8. The off-grid electrochemical system of claim 7, wherein the hydrogen production controller is configured to: limiting the hydrogen production output power of the hydrogen production electrolytic tank according to the active power preset value to obtain ideal hydrogen production output power; adjusting a second phase locking angle of the hydrogen production converter according to the ideal angular frequency and the current voltage of the hydrogen production electrolytic tank to obtain a second angular frequency change rate; and sequentially performing voltage control loop processing and current control loop processing according to the ideal hydrogen production output power, the reactive power preset value and the second angular frequency change rate to obtain the fourth pulse width modulation signal.
9. The off-grid electrochemical system of any one of claims 1-8, wherein the communication between the energy management system, the energy storage subsystem, the power generation subsystem, and the hydrogen production subsystem comprises a high speed communication and a slow speed communication, wherein the transmission rate of the high speed communication is no more than hundred microseconds and the transmission rate of the slow speed communication is hundred milliseconds.
10. The off-grid electrochemical system of any one of claims 1-8, wherein the energy storage subsystem is configured to: According to the energy storage three-phase voltage value and the energy storage three-phase current value, obtaining an active power calculated value and a reactive power calculated value; performing amplitude limiting treatment on the preset active power value to obtain an ideal active power value; and obtaining ideal voltage and ideal angular frequency according to the active power ideal value, the reactive power preset value, the active power calculated value and the reactive power calculated value based on a preset voltage construction strategy.
11. A method of controlling an electrochemical system, the electrochemical system comprising a power generation subsystem, a hydrogen production subsystem, an energy storage subsystem, and an energy management system in communication with the power generation subsystem, the hydrogen production subsystem, and the energy storage subsystem, respectively, the method comprising: determining an ideal voltage and an ideal angular frequency by the energy storage subsystem according to an active power preset value, a reactive power preset value, an energy storage three-phase voltage value and an energy storage three-phase current value, and transmitting the ideal voltage and the ideal angular frequency to the energy management system; And controlling the power generation subsystem to assist the energy storage subsystem in power adjustment or controlling the hydrogen production subsystem to assist the energy storage subsystem in power adjustment by the energy management system according to the ideal voltage and the ideal angular frequency so as to balance the generated power and the used power of the off-grid electrochemical system.
12. A power plant comprising an off-grid electrochemical system according to any one of claims 1-10.

Description

Off-grid electrochemical system, control method of electrochemical system and power station Technical Field The disclosure relates to the technical field of new energy, in particular to an off-grid electrochemical system, a control method of the electrochemical system and a power station. Background At present, most off-grid electrochemical systems are mainly networked in a direct current coupling mode, so that influences on networking voltage and frequency are simplified. However, when the power grid is suddenly changed in the actual operation process, the power grid frequency exceeds the power adjustable range of the energy storage subsystem in the off-grid electrochemical system. When the power grid is suddenly changed, the off-grid electrochemical system cannot realize power regulation when the power grid fluctuates in a wide frequency. Disclosure of Invention In order to solve the defects in the prior art, the purpose of the present disclosure is to provide an off-grid electrochemical system, a control method of the electrochemical system and a power station. In order to achieve the above object, in a first aspect, the present disclosure provides an off-grid electrochemical system, comprising a power generation subsystem, a hydrogen production subsystem, an energy storage subsystem and an energy management system, wherein the energy management system is respectively in communication connection with the power generation subsystem, the hydrogen production subsystem and the energy storage subsystem; The energy storage subsystem is used for determining ideal voltage and ideal angular frequency according to an active power preset value, a reactive power preset value, an energy storage three-phase voltage value and an energy storage three-phase current value and sending the ideal voltage and the ideal angular frequency to the energy management system; The energy management system is used for controlling the power generation subsystem to assist the energy storage subsystem in power adjustment or controlling the hydrogen production subsystem to assist the energy storage subsystem in power adjustment according to the ideal voltage and the ideal angular frequency so as to balance the generated power and the used power of the off-grid electrochemical system. In a second aspect, the present disclosure provides a control method of an electrochemical system, the electrochemical system including a power generation subsystem, a hydrogen production subsystem, an energy storage subsystem, and an energy management system, the energy management system being communicatively connected to the power generation subsystem, the hydrogen production subsystem, and the energy storage subsystem, respectively, the control method comprising: determining an ideal voltage and an ideal angular frequency by the energy storage subsystem according to an active power preset value, a reactive power preset value, an energy storage three-phase voltage value and an energy storage three-phase current value, and transmitting the ideal voltage and the ideal angular frequency to the energy management system; And controlling the power generation subsystem to assist the energy storage subsystem in power adjustment or controlling the hydrogen production subsystem to assist the energy storage subsystem in power adjustment by the energy management system according to the ideal voltage and the ideal angular frequency so as to balance the generated power and the used power of the off-grid electrochemical system. In a third aspect, the present disclosure provides a power plant comprising the off-grid electrochemical system of the first aspect. According to the technical scheme, the energy storage subsystem determines ideal voltage and ideal angular frequency according to the active power preset value, the reactive power preset value, the energy storage three-phase voltage value and the energy storage three-phase current value, and sends the ideal voltage and the ideal angular frequency to the energy management system, and the energy management system controls the power generation subsystem to assist the energy storage subsystem in power adjustment or controls the hydrogen production subsystem to assist the energy storage subsystem in power adjustment according to the ideal angular frequency and the ideal voltage so as to balance the generated power and the electric power of the off-grid electrochemical system, so that the frequency fluctuation range of the off-grid electrochemical system for power adjustment is enlarged, and the off-grid electrochemical system realizes power adjustment when the wide frequency of the power grid fluctuates. Additional features and advantages of the present disclosure will be set forth in the detailed description which follows. Drawings The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification, illustrate the disclosure and t