CN115149552A - Control method of alternating-current coupling off-grid wind power hydrogen production system - Google Patents
Control method of alternating-current coupling off-grid wind power hydrogen production system Download PDFInfo
- Publication number
- CN115149552A CN115149552A CN202210925690.6A CN202210925690A CN115149552A CN 115149552 A CN115149552 A CN 115149552A CN 202210925690 A CN202210925690 A CN 202210925690A CN 115149552 A CN115149552 A CN 115149552A
- Authority
- CN
- China
- Prior art keywords
- power
- hydrogen production
- wind power
- pcs
- energy storage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229910052739 hydrogen Inorganic materials 0.000 title claims abstract description 176
- 239000001257 hydrogen Substances 0.000 title claims abstract description 176
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims abstract description 175
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 170
- 238000000034 method Methods 0.000 title claims abstract description 52
- 230000008878 coupling Effects 0.000 title abstract description 16
- 238000010168 coupling process Methods 0.000 title abstract description 16
- 238000005859 coupling reaction Methods 0.000 title abstract description 16
- 238000004146 energy storage Methods 0.000 claims abstract description 42
- 238000012983 electrochemical energy storage Methods 0.000 claims description 33
- 230000008569 process Effects 0.000 claims description 27
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 238000005868 electrolysis reaction Methods 0.000 claims description 13
- 238000007599 discharging Methods 0.000 claims description 9
- 230000000087 stabilizing effect Effects 0.000 claims description 6
- 238000011217 control strategy Methods 0.000 claims description 5
- 238000003860 storage Methods 0.000 claims description 5
- 230000008859 change Effects 0.000 claims description 4
- 230000002452 interceptive effect Effects 0.000 claims description 4
- 238000010521 absorption reaction Methods 0.000 claims description 3
- 230000009194 climbing Effects 0.000 claims description 3
- 238000005259 measurement Methods 0.000 claims description 3
- 238000010248 power generation Methods 0.000 claims description 3
- 230000001502 supplementing effect Effects 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims 1
- 230000003993 interaction Effects 0.000 abstract 1
- 238000004088 simulation Methods 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J15/00—Systems for storing electric energy
- H02J15/008—Systems for storing electric energy using hydrogen as energy vector
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/004—Generation forecast, e.g. methods or systems for forecasting future energy generation
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
- H02J3/1821—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators
- H02J3/1835—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
- H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/10—The dispersed energy generation being of fossil origin, e.g. diesel generators
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/28—The renewable source being wind energy
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/40—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation wherein a plurality of decentralised, dispersed or local energy generation technologies are operated simultaneously
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention provides a control method of an alternating-current coupling off-grid wind power hydrogen production system, which utilizes a source-load interaction cross starting mode, maximally utilizes the capacity of the existing energy storage system, ensures the normal function of the system, and greatly reduces the requirement of the system on the instantaneous power value of the energy storage system in the off-grid starting stage, thereby reducing the requirement of the off-grid wind power hydrogen production system on the configuration of the energy storage system; the round value switching of the voltage source control and the current source control is carried out through the two sets of PCS, so that on the premise that the configuration of the network PCS meets the minimum requirement of the system, a direct PQ control mode is still adopted by one part of PCS, the wind power high-frequency fluctuation is restrained more actively, quickly, accurately and widely, and the power supply randomness is weakened.
Description
Technical Field
The invention relates to the technical field of hydrogen production by electrolyzing water by using renewable energy sources, in particular to a control method of an alternating-current coupling off-grid wind power hydrogen production system.
Background
The renewable energy water electrolysis hydrogen production technology can convert green electricity into green hydrogen, and is an ideal energy conversion mode. Particularly, the off-grid wind power hydrogen production technology can effectively utilize wind power resources in remote areas, thoroughly avoids the influence of wind power on a power grid, saves transmission line cost, and has important research value. However, the existing off-grid wind power hydrogen production technology has a plurality of problems:
(1) Due to the lack of support of a main grid, an off-grid wind power hydrogen production system is generally required to be provided with an electrochemical energy storage system with a large capacity for establishing the voltage and the frequency of a micro-grid, and rapidly responding to the power deviation of the system in the starting and running stages, and carrying out peak clipping and valley filling. However, electrochemical energy storage systems have extremely high costs, resulting in reduced overall system economics.
(2) The main off-grid wind power hydrogen production system adopts a direct current coupling structure, which requires full-power rectification on the output side of a wind turbine generator, so that a permanent magnet wind turbine generator with higher cost is usually adopted, and the direct current link of a full-power converter of a fan is directly used as final output.
(3) If a double-fed wind turbine is adopted, in order to realize excitation, starting and grid connection of the wind turbine in an off-grid state, a mode that an energy storage cabinet is connected in parallel to a direct current link of an alternating current-direct current converter of the double-fed wind turbine is usually adopted, and an existing wind turbine converter system needs to be modified, so that the cost and the control difficulty are increased.
Disclosure of Invention
The invention aims to solve the problems that an off-grid wind power hydrogen production system has high requirements on the configuration of an energy storage system, and the conventional wind power plant structure is greatly improved, the research and development design cost is high and the like in the prior art.
In order to achieve the above object, the present invention provides a method for controlling an ac-coupled off-grid wind power hydrogen production system, wherein the off-grid wind power hydrogen production system comprises: the system comprises a wind power plant (1) containing a plurality of wind power generation sets, a hydrogen production system (2) containing a plurality of water electrolysis hydrogen production devices, an electrochemical energy storage system (3), a public alternating current bus (4) and SVG devices (5); alternating current coupling's off-grid wind power hydrogen production system configuration public alternating current bus (4), electrochemical energy storage system (3) include PCS, and wind turbine generator system, hydrogen production equipment, PCS, SVG equipment (5) all are connected to public alternating current bus through respective step-up transformer (7) high-pressure side. The off-grid wind power hydrogen production system is connected with the microgrid controller.
The wind power plant (1) comprises a wind turbine generator and a wind power prediction system, wherein the wind power prediction system is used for performing short-term power prediction and transmitting data to the microgrid controller.
The hydrogen production system (2) comprises a plurality of water electrolysis hydrogen production devices and hydrogen production control units which are connected in parallel, and the hydrogen production control units are respectively connected with each water electrolysis hydrogen production device.
The electrochemical energy storage system (3) also comprises a storage battery pack, an EMS (energy management system) and a BMS (battery management system), and the electrochemical energy storage system is used as a starting power supply, realizes the establishment of the voltage frequency of the microgrid through the droop control of the energy storage system, and further supports the starting of each device; in the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn of the single wind turbine and the cold start required power Pcool of the single hydrogen production equipment.
The microgrid controller is used for starting the fans one by one and cold starting the hydrogen production equipment one by one, and is used for actively controlling the operation power point of the hydrogen production equipment to track the change of the wind power output power and adopting MPPT control.
The SVG device (5) is used for supplementing system reactive power deviation in the starting and running processes and maintaining reactive power balance.
The control method of the alternating-current coupled off-grid wind power hydrogen production system comprises the following steps:
the method comprises the following steps: and the wind power prediction system carries out short-term power prediction, and when the average wind power level of 4h in the future is judged to be higher than the minimum running power value of the hydrogen production system, the system enters a starting process.
Step two: the energy storage system PCS rapidly establishes the voltage and the frequency of the microgrid through droop control, and charges an alternating current bus, a current collecting circuit and a transformer. In the charging process, the inrush current is reduced by adopting the modes of line sectional charging and successive input of a transformer.
Thirdly, starting the fans one by one and cold-starting the hydrogen production equipment one by the microgrid controller, rapidly compensating the active and reactive deviations of the system by the electrochemical energy storage and SVG equipment, maintaining balance, controlling the input fans by MPPT (maximum power point tracking), when the maximum total power Pmax which can be generated by the input fans is greater than the cold-starting required power Pcool of the single hydrogen production equipment, cold-starting the first hydrogen production equipment and entering a preheating stage, and when the power of the hydrogen production equipment is increased to Pcool, starting the next fan; similarly, as Pmax is gradually increased, the [ Pmax/Pcool ] (rounding up nearby) hydrogen production equipment is cold started; and in the cold start power climbing stage of the hydrogen production equipment, the electrochemical energy storage compensates the power deviation between the wind power plant and the hydrogen production equipment.
And fourthly, when all the M hydrogen production devices are in cold start and the electric power reaches Pcool, the fans are continuously started one by one, the microgrid controller controls the total output of the wind power plant not to exceed the total power of all the hydrogen production cold start, and part or all of the fans enter a power limiting mode through rotation speed control or pitch angle control.
And step five, starting the water electrolysis hydrogen production equipment to start to produce hydrogen when the cold start reaches the set time and the hydrogen production condition is reached.
Step six: and gradually exiting the power limiting mode by the fan, increasing the output power of the wind power plant according to the rate equivalent to the power-up rate of the hydrogen production system, and realizing the matching with the hydrogen production power until all the wind power generators reach the MPPT state or all the hydrogen production electrolytic cells are in the maximum power state.
Step seven: the system enters a normal operation mode, and the microgrid controller dynamically distributes and updates the power target value of the hydrogen production equipment according to the total power output measurement value of the wind power plant to realize dynamic tracking; because the extreme rise power rate of the wind power is higher than that of the hydrogen production system, when the wind power is increased suddenly, the wind power and the hydrogen production system are coupled by limiting the rise speed of the wind power.
Furthermore, the seventh step of dynamic tracking adopts a source-load interactive cross start mode, the control system collects real-time data of a power supply and a load, dynamically judges and decides the start time and the control mode of each device, and immediately and cold starts the [ Pmax/Pcool ] (rounding up nearby) hydrogen production equipment when the Pmax is gradually increased. In the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn and Pcold of a single wind turbine, namely the minimum requirement of the system on the rated power of the energy storage.
Further, part of electrochemical energy storage is additionally configured, and during operation, PCS is divided into two groups according to a control mode: the total power of any PCS is at least the maximum of Pn and Pcold as described above. The first group of PCS adopts a droop control mode and is used for establishing system voltage and frequency of a microgrid, namely the PCS is used as a voltage source of a system; and the other group of PCS adopts a PQ control strategy for stabilizing the high-frequency fluctuation of the output of the wind power plant and more accurately filling the power difference caused by the randomness of the output of the wind power plant, namely the PCS is used as a current source of the system.
Further, the two groups of PCS can realize the switching of control modes and functions through the BMS, and the switching principle is as follows: when the SOC value of the PCS of the droop control group reaches the upper limit or the lower limit, the PCS of the droop control group is switched to a PQ control mode, and on the basis of ensuring normal functions of stabilizing power fluctuation and filling up a power difference, the target power value is adjusted to charge or discharge the PCS, so that the SOC of the PCS is gradually recovered; meanwhile, the other set of PCS is switched to the droop control mode, which is responsible for establishing the voltage and frequency of the system.
Further, in the seventh step, under the condition of sudden increase of the wind power output, the wind power plant is subjected to power-rise rate limitation, and the power-rise rate is the same as the power-rise rate of the hydrogen production system; and when the wind power output value is higher than the steady-state absorption capacity of the hydrogen production system, carrying out total power limitation on the wind power plant, setting the limit value as the highest absorbable power of the hydrogen production system under the current working condition, and realizing the power limit value through pitch angle control and rotating speed control.
Compared with the conventional technology, the invention has the beneficial effects that:
(1) The system starting control method disclosed by the invention utilizes a source-load interactive cross starting mode, maximally utilizes the capacity of the existing energy storage system, ensures the normal function of the system, and greatly reduces the requirement of the system on the instantaneous power value of the energy storage system in the off-grid starting stage, thereby reducing the requirement of the off-grid wind power hydrogen production system on the configuration of the energy storage system; in addition, the effect that hydrogen production power changes along with wind power changes is optimized to the maximum extent by limiting the power of the wind power plant and limiting the power acceleration within a specific time and a specific time period, and the dependence on an energy storage system in the operation process is also reduced. From these two aspects, the economic nature of system has been promoted.
(2) According to the energy storage system control method under the off-grid wind power hydrogen production scene, the two sets of PCS are used for performing round value switching of voltage source control and current source control, so that on the premise that configuration of the PCS in a network meets minimum requirements of the system, a direct PQ control mode is still adopted by one part of PCS, wind power high-frequency fluctuation is restrained more actively, quickly, accurately and widely, power supply randomness is weakened, and the working reliability of the energy storage system is improved based on the switching principle of the SOC state.
Drawings
FIG. 1: the invention is a schematic diagram of an embodiment of an AC coupling off-grid wind power hydrogen production system;
FIG. 2: the invention relates to a starting flow chart of an alternating current coupling off-grid wind power hydrogen production system;
FIG. 3: an energy storage output active power simulation curve diagram is provided;
wherein, 1, a wind power plant; 2. a hydrogen production system; 3. an electrochemical energy storage system; 4. a common AC bus; 5. An SVG device; 6. a standby diesel generator; 7. a step-up transformer.
Detailed Description
Fig. 1 shows that the configuration of the ac-coupled off-grid wind power hydrogen production system mainly comprises: a wind power field 1 with N double-fed wind power generators, wherein N is larger than 1; the system comprises M hydrogen production systems 2 of alkaline water electrolysis hydrogen production equipment, wherein M is larger than 1, an electrochemical energy storage system 3 containing an accumulator group and a PCS, a public alternating current bus 4, SVG equipment 5 and a standby diesel generator 6. The alternating-current coupling off-grid wind power hydrogen production system operates in an isolated grid mode, and energy exchange and physical connection between the alternating-current coupling off-grid wind power hydrogen production system and a main power grid are avoided.
The wind power plant 1 comprises a wind turbine generator, a box-type step-up transformer, a current collection circuit, a confluence device, a centralized control system and a wind power prediction system. And transmitting the wind power prediction system data to the centralized control system and the microgrid controller. The wind generating set is a variable-pitch variable-speed constant-frequency double-fed asynchronous wind generating set;
the hydrogen production system 2 is an alkaline water electrolysis hydrogen production system, and comprises M sets of water electrolysis hydrogen production equipment connected in parallel, wherein the water electrolysis hydrogen production equipment comprises an electrolytic tank, a converter, a transformer, a control system and auxiliary systems such as purification and hydrogen storage, the operation power of any electrolytic tank can be independently controlled through the control system, and the power fluctuation range is 20-120% of rated power. The rated total power of the hydrogen production system does not exceed 83.3 percent of the rated power of the wind power plant.
The electrochemical energy storage system 3 comprises a storage battery pack, a PCS, an EMS, a BMS and corresponding auxiliary systems, has the response speed ms level, can regulate the power factor within the range of-0.95 to +0.95, and is preferably a lithium iron phosphate storage battery system. The electrochemical energy storage system is used as a starting power supply, the micro-grid voltage frequency is established through droop control of the energy storage system, and further starting of each device is supported; in the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn and Pcool of the single wind turbine generator.
The microgrid controller is used for starting the fans one by one and cold starting the hydrogen production equipment one by one, and is used for actively controlling the operation power point of the hydrogen production equipment to track the change of the wind power output power, and the electrochemical energy storage and SVG equipment quickly compensate the active and reactive deviation of the system, maintain balance and adopt MPPT control;
the alternating-current coupling off-grid wind power hydrogen production system adopts an alternating-current bus coupling mode, and each wind power generator set, each hydrogen production device, each energy storage PCS, SVG device 5 and diesel generator are connected to a public alternating-current bus through the high-voltage side of each boosting transformer 7.
The alternating-current coupling off-grid wind power hydrogen production system adopts an electrochemical energy storage system connected with an alternating-current bus as a micro power supply, realizes the establishment of the voltage frequency of a micro power grid through the droop control of the electrochemical energy storage system, and further supports the starting of each device. The mode that hydrogen production power follows is adopted in the operation process, namely, the operation power point of hydrogen production equipment is actively controlled to track the change of wind power output power, the electrochemical energy storage and SVG equipment can quickly compensate the active and reactive power deviation of the system, balance is maintained, and the standby diesel generator 6 is used as an emergency power supply and is put into use when the system is started for the first time or the SOC of the electrochemical energy storage is lower than the limit value. The system can completely realize isolated network operation, and has no energy exchange or physical connection with a main power grid. The controller can realize real-time monitoring, control and scheduling of each part in the system, control the off-network starting and operation of the system, and ensure the balance and stability of the system through the control method disclosed by the invention in the whole process.
In the alternating-current coupling off-grid wind power hydrogen production system, the rated total electric power configuration scale of the hydrogen production system is at most 83.3% of the installed capacity of the wind power plant, so that the hydrogen production system has no idle capacity when the output power of the wind power plant reaches the maximum.
Referring to fig. 2, the control method of the alternating current coupling off-grid wind power hydrogen production system of the invention specifically comprises the following steps:
the method comprises the following steps: and the wind power prediction system predicts the short-term power, and when the average wind power level of 4h in the future is judged to be higher than the minimum operation power value of the hydrogen production system, the alternating-current coupling off-grid wind power hydrogen production system enters a starting process.
Step two: the energy storage system PCS rapidly establishes the voltage and the frequency of the microgrid through droop control, and charges an alternating current bus, a current collecting circuit and a transformer. In the charging process, the transformers and the current collecting circuits of the No. 1 to No. N fans are sequentially charged, and then the No. 1 to No. M hydrogen production transformers are sequentially charged, so that the inrush current is reduced.
And step three, starting the fan one by one and cold starting the hydrogen production equipment one by the microgrid controller. The method comprises the following steps that MPPT control is carried out on the fans which are put into the system, when the maximum total power Pmax which can be generated by the fans which are put into the system is larger than the power Pcool required by cold start of a single hydrogen production device, a first hydrogen production device is cold started and enters a preheating stage, and when the power of the hydrogen production device is increased to Pcool, the next fan is started; similarly, as Pmax gradually increases, then the [ Pmax/Pcool ] th hydrogen production equipment is started in a cold mode (rounded up nearby); and in the cold start power climbing stage of the hydrogen production equipment, the electrochemical energy storage compensates the power deviation between the wind power plant and the hydrogen production equipment.
Step four, when all the M hydrogen production devices are in cold start and the electric power reaches Pcool, the fans are continuously started one by one, the microgrid controller controls the total output of the wind power plant not to exceed the total power of all the hydrogen production cold start, and part or all of the fans enter a power limiting mode through rotation speed control or pitch angle control;
and step five, starting the electrolytic cell to start to prepare the hydrogen when the hydrogen production condition is reached, wherein the hydrogen production condition is usually about 30 minutes after cold start.
Step six: and the fan gradually exits from the power limiting mode, the output power of the wind power plant is increased according to the rate equivalent to the power-raising rate of the hydrogen production system, and the matching with the hydrogen production power is realized until all the wind power generation sets reach the MPPT state or all the hydrogen production electrolytic tanks are in the maximum power state.
Step seven: the system enters a normal operation mode, and the controller dynamically allocates and updates the power target value of the hydrogen production equipment according to the measured value of the total power output by the wind power plant to realize dynamic tracking; because the extreme power-rise rate of the wind power is higher than that of the hydrogen production system, when the wind power is suddenly increased, the wind power and the hydrogen production system are coupled by adopting a mode of limiting the speed-rise of the wind power, and the investment of an energy storage system is reduced. The dynamic tracking adopts a source-load interactive cross starting mode, a control system collects real-time data of a power supply and a load, dynamically judges and decides the starting time and the control mode of each device, and when the Pmax is gradually increased, the hydrogen production device is cold started immediately (Pmax/Pcold is rounded up nearby). In the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn and Pcool of a single wind turbine generator, namely the minimum requirement of the system on the rated power of the energy storage is met, and the system cost is greatly reduced.
Under the condition of sudden increase of wind power output, limiting the power-rise rate of the wind power plant, wherein the power-rise rate is the same as the power-rise rate of the hydrogen production system; when the wind power output value is higher than the steady-state absorption capacity of the hydrogen production system, the total power of the wind power plant is limited, the limit value is set to be the highest absorbable power of the hydrogen production system under the current working condition, and the power limit value is realized through pitch angle control and rotating speed control.
According to the starting and operating strategy disclosed by the invention, in the process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn and Pcool of a single wind turbine generator, namely the minimum requirement of the off-grid hydrogen production system on the rated power of the energy storage system is met, and the system cost is greatly reduced.
FIG. 3 is a simulation graph of the output active power of the energy storage system in the embodiment (FIG. 1), in the simulation model, the rated power of a single wind turbine generator is 2.5MW, the rated power of a single hydrogen production device is 5MW, and Pcool is considered according to 1 MW. The simulation model simulates the process from the start-up procedure of the system to the start-up of 4 fans and 4 hydrogen production devices and enters the power limiting mode, and the control strategy is executed according to the off-grid wind power hydrogen production start-up control method disclosed by the invention. It can be seen that in the whole process, the maximum value of the charging power and the discharging power of the energy storage system does not exceed the rated power Pn =2.5MW of a single wind turbine, namely the energy storage system is regarded as the minimum configuration necessary for the system.
On the basis of the necessary energy storage configuration, preferably, part of the electrochemical energy storage system is additionally configured, and in the operation process, the PCS is divided into two groups according to a control mode: the total power of any PCS is at least the maximum of Pn and Pcold as described above. In the operation process, the first group of PCS adopts a droop control mode and is used for establishing system voltage and frequency of a microgrid, namely the system voltage and frequency are used as a voltage source of the system; and the other group of PCS adopts a PQ control strategy for stabilizing the high-frequency fluctuation of the output of the wind power plant and more accurately filling the power difference caused by the randomness of the output of the wind power plant, namely the PCS is used as a current source of the system. Two sets of PCS can realize the switching of control mode and function through BMS, and the principle of switching is: when the SOC value of the PCS of the droop control group is about to reach the upper limit or the lower limit of the SOC, the control group is switched to a PQ control mode, and on the basis of ensuring normal functions of stabilizing power fluctuation and filling up a power difference, the target power value is adjusted to charge or discharge the control group, so that the SOC of the control group is gradually recovered; meanwhile, the other set of PCS is switched to the droop control mode, which is responsible for establishing the voltage and frequency of the system.
Under the strategy of double set PCS wheel value control, the energy storage system can be effectively ensured to work uninterruptedly, the power supply quality of a system power supply is greatly improved, and the work safety of the hydrogen production system is favorably improved.
For example, the system configuration is as follows: the rated installed capacity of the wind power plant is 50MW, and the wind power plant is composed of 20 2.5MW double-fed wind generating sets, and the serial numbers of the double-fed wind generating sets are respectively No. 1 fan to No. 20 fan; the rated hydrogen production capacity of the hydrogen production system is 8000Nm3/h, the hydrogen production system consists of 8 sets of electrolytic tanks with the hydrogen production capacity of 1000Nm3/h and rectifying and pressure changing devices thereof, the number of the electrolytic tanks is from No. 1 hydrogen production equipment to No. 8 hydrogen production equipment, and the total rated power is about 40MW; the electrochemical energy storage system is configured to be 5MW/1h, wherein 2.5MW is necessary configuration, in addition, 2.5MW is additional configuration of a preferred scheme, and the electrochemical energy storage system is composed of 4 sets of PCS with rated power of 1.25 MW; the rated power of the SVG equipment is 10MW; the rated power of the diesel generator is 2MW.
The total operating power range of the hydrogen production equipment is 0% to 120% of rated power, namely the maximum possible over power is 40 multiplied by 120% =48MW operation, and when the wind power plant is in full power, after line loss, the whole power can be basically absorbed by the hydrogen production system. The rated power of the energy storage system is 5MW, and the system can bear the full load removal of at most two fans or one hydrogen production device.
Taking the wind speed of 8m/s as an example, the system starting process is described as follows:
the method comprises the following steps: and the wind power prediction system carries out short-term power prediction, and when the average wind power level of 4h in the future is judged to be higher than the minimum running power value of the hydrogen production system, the system enters a starting process.
Step two: the energy storage system 4 sets of PCS establish the voltage and frequency of the microgrid together through droop control, and charge the alternating current bus, the current collection circuit and the transformer. In the charging process, the inrush current is reduced by adopting the mode of line sectional charging and successive transformer investment.
And step three, starting the fans one by one, and cold starting the hydrogen production equipment one by one. The method comprises the following specific steps: (1) Starting a No. 1 fan, wherein Pmax =1.5MW, and the charging power of the energy storage system is increased to 1.5MW; (2) Starting No. 1 hydrogen production equipment, heating the equipment according to Pcoled =20% multiplied by 5MW =1MW power, wherein at the moment, 0.5MW wind power is still not utilized, and the electrochemical energy storage automatically reduces the charging power to 0.5MW; (3) Starting a No. 2 fan, wherein Pmax =3MW, and the electrochemical energy storage automatically improves the charging power to 2MW; (4) The hydrogen production equipment No. 2 and No. 3 are started in sequence, and the charging power is automatically reduced to 0MW by electrochemical energy storage; (5) Starting a No. 3 fan, wherein Pmax =4.5MW, and the electrochemical energy storage automatically improves the charging power to 1.5MW; (6) And starting No. 4 hydrogen production equipment, wherein hydrogen production absorbs 4MW power, the charging power of the energy storage system is converted into 0.5MW, and the like.
Step four: when all 8 hydrogen production devices are in cold start and electric power reaches Pcool, the fans are continuously started one by one, the microgrid controller controls the total output of the wind power plant not to exceed the total power of all hydrogen production cold start, and part or all of the fans enter a power limiting mode through rotation speed control or pitch angle control;
and step five, starting the electrolytic cell 30 minutes after cold start to prepare hydrogen.
Step six: and gradually exiting the power limiting mode by the fan, increasing the output power of the wind power plant according to the rate equivalent to the power-up rate of the hydrogen production system, and realizing the matching with the hydrogen production power until all the wind power generators reach the MPPT state or all the hydrogen production electrolytic cells are in the maximum power state.
Step seven: the system enters a normal operation mode, and the microgrid controller dynamically distributes a power target value of the hydrogen production equipment according to a total power measurement value output by the wind power plant to realize dynamic tracking;
fig. 3 is a simulation curve diagram of the output active power of the energy storage system in the embodiment of the invention in fig. 1, the simulation model simulates the process from the start of the system to the start of 4 fans and 4 hydrogen production devices and enters a power limiting mode, and the control strategy is executed according to the off-grid wind power hydrogen production start control method disclosed by the invention.
Preferably, 4 sets of PCS are divided into two groups, namely a group A and a group B, wherein each group consists of 2 sets of PCS with the MW of 1.25, and the group A adopts droop control as a voltage source of the system in the operation process; group B adopts PQ control as the voltage source of the system; two sets of PCS can realize the switching of control mode through energy storage controller, and the principle of switching is: when the SOC value of the PCS of the droop control group is about to reach the upper limit or the lower limit of the SOC, the PCS of the droop control group is switched to a PQ control mode to carry out charging and discharging adjustment, and meanwhile, the PCS of the other group is switched to droop control to be responsible for establishing the voltage and the frequency of the system.
Claims (5)
1. A control method of an alternating current coupled off-grid wind power hydrogen production system comprises the following steps: the system comprises a wind power plant (1) comprising a plurality of wind power generation sets, a hydrogen production system (2) comprising a plurality of water electrolysis hydrogen production devices, an electrochemical energy storage system (3), a public alternating current bus (4) and an SVG device (5); the alternating-current coupled off-grid wind power hydrogen production system is provided with a public alternating-current bus (4), the electrochemical energy storage system (3) comprises a PCS, and the wind power generator set, the hydrogen production equipment, the PCS and the SVG equipment (5) are connected to the public alternating-current bus through the high-voltage sides of respective step-up transformers (7); the off-grid wind power hydrogen production system is connected with the microgrid controller;
the wind power plant (1) comprises a wind turbine generator and a wind power prediction system, wherein the wind power prediction system is used for performing short-term power prediction and transmitting data to the microgrid controller;
the hydrogen production system (2) comprises a plurality of water electrolysis hydrogen production devices and hydrogen production control units which are connected in parallel, and the hydrogen production control units are respectively connected with each water electrolysis hydrogen production device;
the electrochemical energy storage system (3) also comprises a storage battery pack, an EMS (energy management system) and a BMS (battery management system), and the electrochemical energy storage system is used as a starting power supply, realizes the establishment of the voltage frequency of the microgrid through the droop control of the energy storage system, and further supports the starting of each device; in the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn of a single wind turbine and the cold start required power Pcool of a single hydrogen production device;
the microgrid controller is used for starting the fans one by one and cold starting the hydrogen production equipment one by one, and is used for actively controlling the operation power point of the hydrogen production equipment to track the change of the wind power output power and adopting MPPT control;
the SVG equipment (5) is used for supplementing system reactive power deviation in the starting and running processes and maintaining reactive power balance;
it is characterized in that the preparation method is characterized in that,
the control method of the alternating-current coupled off-grid wind power hydrogen production system comprises the following steps:
the method comprises the following steps: the wind power prediction system carries out short-term power prediction, and when the average wind power level of 4h in the future is judged to be higher than the minimum operation power value of the hydrogen production system, the system enters a starting process;
step two: the energy storage system PCS rapidly establishes the voltage and the frequency of the microgrid through droop control, and charges an alternating current bus, a current collecting circuit and a transformer. In the charging process, the inrush current is reduced by adopting the way of line sectional charging and successive transformer investment;
thirdly, starting the fans one by one and cold-starting the hydrogen production equipment one by the microgrid controller, rapidly compensating the active and reactive deviations of the system by the electrochemical energy storage and SVG equipment, maintaining balance, controlling the input fans by MPPT (maximum power point tracking), when the maximum total power Pmax which can be generated by the input fans is greater than the cold-starting required power Pcool of the single hydrogen production equipment, cold-starting the first hydrogen production equipment and entering a preheating stage, and when the power of the hydrogen production equipment is increased to Pcool, starting the next fan; similarly, as Pmax is gradually increased, the [ Pmax/Pcool ] (rounding up nearby) hydrogen production equipment is cold started; in the cold start power climbing stage of the hydrogen production equipment, the electrochemical energy storage compensates the power deviation between the wind power plant and the hydrogen production equipment;
step four, when all the M hydrogen production devices are in cold start and the electric power reaches Pcool, the fans are continuously started one by one, the microgrid controller controls the total output of the wind power plant not to exceed the total power of all the hydrogen production cold start, and part or all of the fans enter a power limiting mode through rotation speed control or pitch angle control;
step five, starting the water electrolysis hydrogen production equipment to start to produce hydrogen when the cold start reaches the set time and the hydrogen production condition is reached;
step six: the fan gradually exits the power limiting mode, the output power of the wind power plant is increased according to the rate equivalent to the power rise rate of the hydrogen production system, and the matching with the hydrogen production power is realized until all the wind power generators reach the MPPT state or all the hydrogen production electrolytic cells are in the maximum power state;
step seven: the system enters a normal operation mode, and the microgrid controller dynamically distributes and updates the power target value of the hydrogen production equipment according to the total power output measurement value of the wind power plant to realize dynamic tracking; because the extreme power-rise rate of the wind power is higher than that of the hydrogen production system, when the wind power is suddenly increased, the wind power is limited to be raised, and the wind power and the hydrogen production system are coupled.
2. The control method of the alternating-current coupled off-grid wind power hydrogen production system according to claim 1, wherein the seventh step of dynamic tracking adopts a source-load interactive cross start mode, the control system collects real-time data of a power supply and a load, dynamically judges and decides the start time and the control mode of each device, and when Pmax is gradually increased, the [ Pmax/Pcold ] (complete nearby) hydrogen production device is cold started immediately. In the starting process, the instantaneous charging and discharging power of the energy storage system does not exceed the maximum value of the rated power Pn and Pcool of the single wind turbine generator, namely the minimum requirement of the system on the rated power of the energy storage.
3. The control method of the AC-coupled off-grid wind power hydrogen production system according to claim 2, wherein preferably, part of electrochemical energy storage is additionally configured, and during operation, PCS is divided into two groups according to a control mode: the total power of any one group of PCS is at least the maximum value of Pn and Pcoled. The first group of PCS adopts a droop control mode and is used for establishing system voltage and frequency of a microgrid, namely the PCS is used as a voltage source of a system; and the other group of PCS adopts a PQ control strategy for stabilizing the high-frequency fluctuation of the output of the wind power plant and more accurately filling the power difference caused by the randomness of the output of the wind power plant, namely the PCS is used as a current source of the system.
4. The control method of the AC-coupled off-grid wind power hydrogen production system according to claim 3, wherein the two groups of PCS can realize the switching of control modes and functions through BMS, and the switching principle is as follows: when the SOC value of the PCS of the droop control group reaches the upper limit or the lower limit, the PCS of the droop control group is switched to a PQ control mode, and on the basis of ensuring normal functions of stabilizing power fluctuation and filling up a power difference, the target power value is adjusted to charge or discharge the PCS, so that the SOC of the PCS is gradually recovered; meanwhile, the other set of PCS is switched to the droop control mode, which is responsible for establishing the voltage and frequency of the system.
5. The method for controlling the AC-coupled off-grid wind power hydrogen production system according to claim 1, wherein in the seventh step, under the condition of sudden increase of wind power output, the wind power plant is subjected to power-rise rate limitation, and the power-rise rate is the same as the power-rise rate of the hydrogen production system; when the wind power output value is higher than the steady-state absorption capacity of the hydrogen production system, the total power of the wind power plant is limited, the limit value is set to be the highest absorbable power of the hydrogen production system under the current working condition, and the power limit value is realized through pitch angle control and rotating speed control.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210925690.6A CN115149552B (en) | 2022-08-03 | 2022-08-03 | Control method of alternating-current coupling off-grid wind power hydrogen production system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210925690.6A CN115149552B (en) | 2022-08-03 | 2022-08-03 | Control method of alternating-current coupling off-grid wind power hydrogen production system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115149552A true CN115149552A (en) | 2022-10-04 |
| CN115149552B CN115149552B (en) | 2024-06-11 |
Family
ID=83413246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210925690.6A Active CN115149552B (en) | 2022-08-03 | 2022-08-03 | Control method of alternating-current coupling off-grid wind power hydrogen production system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115149552B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117595331A (en) * | 2024-01-18 | 2024-02-23 | 中国科学院电工研究所 | Gravity energy storage multi-unit power flexible compensation method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102522763A (en) * | 2011-12-23 | 2012-06-27 | 中国电力科学研究院 | Control method for stabilizing fluctuation of wind power by energy storage system |
| WO2014201849A1 (en) * | 2013-06-18 | 2014-12-24 | 国网辽宁省电力有限公司电力科学研究院 | Method for actively optimizing, adjusting and controlling distributed wind power plant provided with energy-storage power station |
| CN111668869A (en) * | 2020-06-10 | 2020-09-15 | 中国电力工程顾问集团华北电力设计院有限公司 | Off-grid wind power hydrogen production system and capacity matching method thereof |
| CN114204606A (en) * | 2021-11-30 | 2022-03-18 | 中国科学院电工研究所 | Wind-hydrogen-storage system operation mode design method |
| CN114362138A (en) * | 2021-11-29 | 2022-04-15 | 国网河南省电力公司驻马店供电公司 | Source-load-network-storage micro-grid suitable for water resource rich areas |
| CN114389300A (en) * | 2020-10-16 | 2022-04-22 | 上海绿巨人爱爵能源科技有限公司 | Off-grid micro-grid water electrolysis hydrogen production system and control method thereof |
-
2022
- 2022-08-03 CN CN202210925690.6A patent/CN115149552B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102522763A (en) * | 2011-12-23 | 2012-06-27 | 中国电力科学研究院 | Control method for stabilizing fluctuation of wind power by energy storage system |
| WO2014201849A1 (en) * | 2013-06-18 | 2014-12-24 | 国网辽宁省电力有限公司电力科学研究院 | Method for actively optimizing, adjusting and controlling distributed wind power plant provided with energy-storage power station |
| CN111668869A (en) * | 2020-06-10 | 2020-09-15 | 中国电力工程顾问集团华北电力设计院有限公司 | Off-grid wind power hydrogen production system and capacity matching method thereof |
| CN114389300A (en) * | 2020-10-16 | 2022-04-22 | 上海绿巨人爱爵能源科技有限公司 | Off-grid micro-grid water electrolysis hydrogen production system and control method thereof |
| CN114362138A (en) * | 2021-11-29 | 2022-04-15 | 国网河南省电力公司驻马店供电公司 | Source-load-network-storage micro-grid suitable for water resource rich areas |
| CN114204606A (en) * | 2021-11-30 | 2022-03-18 | 中国科学院电工研究所 | Wind-hydrogen-storage system operation mode design method |
Non-Patent Citations (1)
| Title |
|---|
| 崔红芬;王德顺;杨波;吴福保;朱天天;赵晶晶;: "支撑电网黑启动的风光储新能源电站协调控制策略", 电力建设, no. 09, 1 September 2020 (2020-09-01) * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117595331A (en) * | 2024-01-18 | 2024-02-23 | 中国科学院电工研究所 | Gravity energy storage multi-unit power flexible compensation method |
| CN117595331B (en) * | 2024-01-18 | 2024-03-22 | 中国科学院电工研究所 | Gravity energy storage multi-unit power flexible compensation method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115149552B (en) | 2024-06-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105186660B (en) | Off-network type wind power hydrogen production converting system | |
| CN106026168B (en) | The energy management strategies of honourable energy storage wisdom energy tower | |
| CN114024327B (en) | Renewable energy source based power generation multifunctional complementary control system and method | |
| CN114552659A (en) | Multi-energy comprehensive management type energy router containing electricity, hydrogen and energy storage and control method | |
| CN105932704A (en) | Photovoltaic direct current side energy storage based power grid intelligent regulation and control system | |
| CN114336678B (en) | PMU-based primary frequency modulation control method for wind-solar energy storage station | |
| CN105978008A (en) | Flow battery energy storage system with wind field black-start function and work method thereof | |
| CN106953356A (en) | Under a kind of island mode without energy storage wind-solar-diesel complementary electric power system and method | |
| CN103560533B (en) | The method and system of the level and smooth wind light generation fluctuation of energy-accumulating power station are controlled based on rate of change | |
| CN115149552B (en) | Control method of alternating-current coupling off-grid wind power hydrogen production system | |
| CN114481179A (en) | Medium-voltage direct-current collection type renewable energy power generation and hydrogen production system and working method thereof | |
| CN105939024A (en) | Intelligent distributed type wind power generation system capable of adjusting voltage and power | |
| CN210297268U (en) | Hybrid energy storage system for thermal power combined AGC frequency modulation | |
| CN115224704B (en) | Time-sharing multiplexing peak regulation and frequency modulation power station constructed based on hybrid energy storage and control method | |
| Zhou et al. | Stability simulation of a MW-scale PV-small hydro autonomous hybrid system | |
| CN218102598U (en) | Time-sharing multiplexing peak-load-regulation frequency-modulation power station constructed based on hybrid energy storage | |
| Pozo et al. | Battery energy storage system for a hybrid generation system grid connected using fuzzy controllers | |
| CN206894253U (en) | A kind of power network intelligent control system based on the energy storage of photovoltaic DC side | |
| CN116093972A (en) | Novel wind power plant frequency modulation and inertia control system combined with energy storage and novel wind power plant | |
| CN114172199A (en) | Method for realizing frequency modulation and virtual inertia response by using energy storage wind power integrated unit | |
| CN116093931A (en) | Edge-calculation-based source network load storage coordination control system | |
| Gundogdu et al. | Bi-directional power control of grid-tied battery energy storage system operating in frequency regulation | |
| CN115409399A (en) | Novel power system oriented composite energy storage optimal scheduling system and method | |
| Honghai et al. | Research of super capacitor energy storage system based on DG connected to power grid | |
| CN219067870U (en) | Frequency modulation system based on flywheel energy storage |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant |