CN110690730B - Power and energy control method for hybrid power ship - Google Patents
Power and energy control method for hybrid power ship Download PDFInfo
- Publication number
- CN110690730B CN110690730B CN201910975575.8A CN201910975575A CN110690730B CN 110690730 B CN110690730 B CN 110690730B CN 201910975575 A CN201910975575 A CN 201910975575A CN 110690730 B CN110690730 B CN 110690730B
- Authority
- CN
- China
- Prior art keywords
- power
- layer
- output
- power generation
- controller
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000010248 power generation Methods 0.000 claims abstract description 91
- 238000012937 correction Methods 0.000 claims abstract description 20
- 238000011084 recovery Methods 0.000 claims abstract description 18
- 238000005457 optimization Methods 0.000 claims abstract description 17
- 238000004891 communication Methods 0.000 claims description 27
- 238000004146 energy storage Methods 0.000 claims description 11
- 239000003990 capacitor Substances 0.000 claims description 10
- 230000001960 triggered effect Effects 0.000 claims description 10
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 7
- 229910052744 lithium Inorganic materials 0.000 claims description 7
- 238000004364 calculation method Methods 0.000 claims description 6
- 230000003068 static effect Effects 0.000 claims description 6
- 230000004044 response Effects 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 230000009466 transformation Effects 0.000 claims description 3
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 238000001914 filtration Methods 0.000 claims description 2
- 238000007665 sagging Methods 0.000 abstract description 11
- 230000033228 biological regulation Effects 0.000 abstract description 3
- 230000009123 feedback regulation Effects 0.000 abstract description 2
- 238000007726 management method Methods 0.000 description 21
- 239000000446 fuel Substances 0.000 description 8
- 239000007789 gas Substances 0.000 description 6
- 230000007547 defect Effects 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 5
- 230000001133 acceleration Effects 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000003111 delayed effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003344 environmental pollutant Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000003032 molecular docking Methods 0.000 description 2
- 231100000719 pollutant Toxicity 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000002457 bidirectional effect Effects 0.000 description 1
- 210000004556 brain Anatomy 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000009194 climbing Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000001934 delay Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002829 reductive effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000011426 transformation method Methods 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
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
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H21/00—Use of propulsion power plant or units on vessels
- B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H21/00—Use of propulsion power plant or units on vessels
- B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
- B63H2021/202—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- Ocean & Marine Engineering (AREA)
- Control Of Eletrric Generators (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention provides a power and energy control method of a hybrid power ship. The layered control architecture of the hybrid power system is divided into an execution layer, a middle layer and a decision layer; the decision layer decides to obtain the output power of each power generation device; when the intermediate layer fails to receive the power instruction issued by the decision layer on time, the intermediate layer and the execution layer are controlled in a combined way, and after recovery, the whole system level optimization of the ship power system is performed; the output power of the power generation equipment is subjected to feedback regulation by an output power regulation controller of the middle layer; generating a voltage deviation correction term by the bus voltage recovery controller, and outputting the voltage deviation correction term to the sagging controller of the execution layer; executing a layer triggering sagging coefficient self-adjusting function to adjust the sagging coefficient of the power generation equipment; the execution layer controls the power generation equipment and the converter thereof to realize the adjustment of the output power of each power generation equipment. According to the invention, the economic and environment-friendly optimization management in the operation of the power system can be implemented only by collecting part of necessary information of the power system.
Description
Technical Field
The invention relates to a control method of a ship power system, in particular to a power/energy management method of a hybrid power electric propulsion ship.
Background
In the maritime shipping field, economy and environmental protection have been topics of interest. Early electric propulsion was powered by a hot gas engine such as a gas turbine or a diesel engine as a prime mover. Taking a diesel-electric propulsion system as an example, the capacity of a diesel generator set needs to be determined according to the maximum power demand that may occur during sailing. In the actual operation, the maximum power output of the power generation system is not required, but is more in a lower load operation state. The specific fuel consumption-power characteristics of the diesel generator show that the optimal operating point is generally about 80% of rated power, and long-term deviation from the optimal operating point can reduce the fuel utilization rate, so that the problems of low fuel utilization efficiency, increased carbon/nitrogen and other emissions and the like are caused. With the maturity of renewable energy source technology and energy storage technology, the adoption of energy storage devices or clean energy sources and traditional power generation equipment to form a multi-source hybrid power supply system becomes a new trend. Because the traditional alternating current network needs to consider the problems of synchronization, phase modulation and the like, when a plurality of power generation devices are connected, the voltage and the frequency are required to meet the conditions at the same time, and the system is more complex. And the ship adopts the direct current power distribution technology, so that the parallel operation of different types of power generation equipment can be realized more conveniently, and meanwhile, the problems of reactive power flow and the like are avoided.
For hybrid vessels, coordinated control of various power supply equipment is required to fully exploit its advantages, while also enabling economical and green operation of the whole vessel. Implementing power/energy management control is one means of achieving this. At present, centralized control is mostly adopted for a power/energy management method of a hybrid power ship. The patent document with the application number of CN201710284023 proposes a hybrid power ship energy management system based on wavelet-fuzzy logic and a control method, wherein the power demand is decomposed into three frequency bands of high, medium and low by utilizing a wavelet transformation method, and the three frequency bands are respectively distributed as initial reference powers of a super capacitor, a storage battery and a fuel cell; fuzzy logic is then formulated to correct the initial reference power based on the power demand and the SOC of the hybrid energy storage device. Although the method can reasonably realize power distribution, the method has the defects of high requirement on a communication network and strong dependence, and when any communication link fails or communication delay exists, the power balance of the system cannot be ensured. In the energy management and control method of the hybrid power ship electric propulsion system proposed in the patent document with the application number of CN201310264651, the ship hybrid power system is divided into two working modes of diesel hybrid power supply and pure electric power, and the logic of mode switching is formulated according to the supply and demand relation of the SOC of the energy storage device and the system power. Load power is subjected to peak clipping and valley filling through energy storage, so that economic operation of the generator set is maintained. However, the management method is proposed to acquire the power of each part of the system in real time and transmit the power in real time, and the invention has the defect that the centralized control is strongly dependent on the communication capability of the system. Meanwhile, the simple logic judgment is difficult to make an optimal operation scheme of the system under the condition of complex and changeable external conditions.
In order to avoid the defect of strong dependence of centralized control on communication, a distributed control system for ship direct current comprehensive power is disclosed in the patent document with the application number of CN201610523930, a local controller is utilized to control a direct current power generation unit in a power system, a central controller and communication equipment are omitted, and the reliability of the ship medium voltage direct current comprehensive power control system is improved. However, the invention only focuses on the rapid stabilization of the voltage of the direct current bus, and the information of each part cannot be integrated and utilized due to the lack of a certain communication support, so that performance limitation exists when the optimized dispatching of the system level and the control of the higher level are performed.
Disclosure of Invention
The invention aims to provide a power and energy control method of a hybrid power ship, which is reliable and takes system level into consideration.
The purpose of the invention is realized in the following way:
(1) Establishing a layered control architecture of the hybrid power system, wherein the layered control architecture comprises an execution layer, an intermediate layer and a decision layer;
(2) The decision layer performs optimization calculation through pre-recorded historical voyage data and set targets, corrects the pre-recorded historical voyage data by combining with the real-time collected operation information of the hybrid power system, and obtains the output power of each power generation device through decision;
(3) The decision layer simultaneously transmits the command updating period to the middle layer, the middle layer checks whether the control command is updated on time, when the middle layer fails to receive the power command transmitted by the decision layer on time, the middle layer and the execution layer are controlled in a combined mode, and after communication is waited for recovery, the decision layer performs optimized power/energy management of the whole system layer of the ship power system;
(4) When the decision layer has instruction update, the output power adjustment controller of the middle layer is synchronously triggered, responds to the power instruction of the decision layer, and the controller carries out feedback adjustment on the output power of the power generation equipment and outputs a power deviation correction term generated by the controller to the droop controller of the execution layer;
(5) Detecting the direct current bus voltage in real time, triggering a bus voltage recovery controller according to the requirement, generating a voltage deviation correction term after the controller works, and outputting the voltage deviation correction term to a sagging controller of an execution layer;
(6) The execution layer receives a control instruction from the middle layer, directly reads local information through droop control on power coordination among a plurality of parallel power generation devices, obtains the use state of the current power generation device, triggers a droop coefficient self-adjusting function when an index reaches a set threshold value, and adjusts the droop coefficient of the power generation device;
(7) The execution layer controls the power generation equipment and the converter thereof to realize the adjustment of the output power of each power generation equipment.
Aiming at the problems that the types of power sources in the hybrid power ship are multiple, the requirement on a communication network is high and the dependence is strong by singly adopting a centralized control method, and global information cannot be considered and global optimization cannot be realized by singly adopting a decentralized control method, the invention applies layered control to a ship hybrid power system and provides a power/energy management strategy based on layered control for the hybrid power ship.
Compared with the prior art, the layering control method provided by the invention has the beneficial effects that:
(1) The advantages of centralized control and decentralized control are organically combined, the requirement of the centralized control on communication is reduced, and the defect of the centralized control on communication is avoided; meanwhile, compared with decentralized control, the information of the power system can be utilized more comprehensively, the optimization of the power level of the whole ship can be realized, and further, support and technical foundation are provided for realizing advanced functions of ship energy management.
(2) In the aspect of power/energy scheduling, the invention considers the optimization of equipment level and all system level, and in the implementation, the economic and environment-friendly optimization management in the operation of the power system can be implemented only by collecting part of necessary information of the power system.
Drawings
Fig. 1 is a power distribution structure of a hybrid ship.
Fig. 2 is a schematic diagram of a communication connection for hierarchical control.
Fig. 3 is a general block diagram of hierarchical control.
Fig. 4 is a control flow chart of the hierarchical control.
FIG. 5 is a typical sag curve for different types of power generation equipment.
FIG. 6-1 is a droop control flow for a stationary type power plant.
FIG. 6-2 is a droop control flow for a rotary-type power generation apparatus.
Fig. 7 is a trigger flow of the bus voltage recovery controller.
Detailed Description
The hybrid power system comprises a hybrid power generation subsystem, a power distribution subsystem, a propulsion motor, a propeller, other shipborne alternating current/direct current loads and corresponding power electronic conversion devices. The hybrid power generation subsystem comprises a rotary power generation device (a diesel generator set and an AC/DC converter) and a static power generation device (a super capacitor bank, a lithium battery bank and a DC/DC converter).
The invention relates to a power and energy control method of a hybrid power ship, which is a power/energy management method of the hybrid power ship based on layered control, and comprises the following steps:
(1) A hierarchical control architecture of the hybrid powertrain system is established. Including an execution layer (main control layer), a middle layer (secondary control layer) and a decision layer (top control layer).
(2) The decision layer performs optimization calculation according to manually set targets (such as targets of optimal emission, optimal fuel efficiency and the like) through pre-recorded historical range data, corrects the targets by combining system operation information acquired in real time, and obtains the output power of each power generation device through decision.
(3) To ensure stable operation of the system, the decision layer simultaneously issues a cycle of command updates to the middle layer so that the middle layer checks whether the control commands are updated on time ("on time" refers to a time in which normal communication delays are considered). When the intermediate layer fails to receive the power instruction issued by the decision layer on time, the intermediate layer and the execution layer are controlled in a combined way, so that the voltage stability of the bus of the system is maintained as a primary target, and the stable operation of the power system is ensured. And after waiting for communication recovery, the decision layer performs optimized power/energy management on the whole system level of the ship power system.
(4) When the decision layer has instruction update, the output power adjusting controller of the middle layer is synchronously triggered to respond to the power instruction of the decision layer. The controller performs feedback adjustment on the output power of the power generation equipment, and outputs the power deviation correction term generated by the controller to the sagging controller of the execution layer.
(5) The direct current bus voltage is detected in real time, and a bus voltage recovery controller is triggered as required, and a voltage deviation correction term is generated after the controller works and is output to a sagging controller of an execution layer.
(6) The execution layer receives the control instruction from the middle layer, and realizes the power coordination control among the plurality of parallel power generation devices through droop control. The execution layer can directly read the local information to obtain the current use state of the power generation equipment, and when certain indexes reach a set threshold value, the droop coefficient self-adjusting function is triggered to adjust the droop coefficient of the power generation equipment.
(7) Finally, the execution layer controls the power generation devices and the converters thereof to realize the adjustment of the output power of each power generation device.
In order to more clearly illustrate the embodiments of the present invention, the embodiments are described below with reference to the accompanying drawings. The drawings are mainly used for illustration and auxiliary description, not only the structure, but also other changed electric grid structures taking the direct current bus as the backbone can be implemented by adopting the method of the invention.
It should be noted that: fig. 5 is used only to demonstrate the droop characteristics (single/two quadrant) of different types of power generation devices, and is not the only case of this type of device droop. Fig. 6-2 illustrates droop control of the rotary power generation apparatus according to this embodiment, in which a permanent magnet synchronous motor driven by a diesel engine is used as a power generator set, and the power generator set is only a component of a gas turbine power generator set, and the prime mover and the power generator are selected from other forms, such as: gas turbine, synchronous generator. Likewise, the choice of rectifying device should be combined with voltage class, transmission power and other engineering requirements, preferably with suitable rectifying devices such as: MMC (modular multilevel converter), multi-pulse diode/thyristor rectification, etc.
Aiming at the problems that the types of power sources in the hybrid power ship are various, the requirement on a communication network is high and the dependence is strong by adopting a centralized control method singly, and the global information cannot be considered and the global optimization cannot be realized by adopting a decentralized control method singly, the invention applies the hierarchical control to a ship hybrid power system, provides a power/energy management strategy of the hybrid power ship based on the hierarchical control, and can control the power of the hybrid energy by combining the optimization operation of a system level.
Hybrid vessels employ a three-layer control architecture that uses a communications network but is not entirely dependent; when the system communication is blocked/delayed or the local/global communication is failed, the lower control layers (the execution layer and the middle layer) independently work to complete corresponding control tasks, and the optimal and stable running power/energy management of the non-whole system level of the ship power system is maintained.
Fig. 1 is a power distribution structure of a hybrid ship to which the present invention is applied. The hybrid power generation subsystem consists of a diesel generator set, a lithium battery set and a super capacitor set. The diesel generator set is connected to the main bus after being rectified by the voltage source converter, and the lithium battery set and the super capacitor set are connected to the main bus through the bidirectional DC/DC converter (or through the multiport DC/DC converter) respectively. The ship hybrid power system adopts a direct-current power distribution framework with multiple direct-current voltage levels and adopts double bus redundancy configuration. The electric load of the ship is mainly divided into two major categories, namely electric propulsion load (propulsion inverter-propulsion motor-propeller) and service load (ac/dc). The electric propulsion load is directly connected with the main direct current bus, and the service load is connected with the secondary low-voltage direct current bus and is provided with a corresponding electric converter according to the load type.
Overall architecture of hierarchical control and roles of layers
Fig. 3 is an overall architecture of hierarchical control. The roles of the layers are as follows:
(1) The execution layer: and the droop control is adopted to realize power distribution among different grid-connected power generation equipment, receive and execute instructions issued by an upper control layer, and provide a droop coefficient self-adjustment function.
(2) An intermediate layer: the method is used for the voltage recovery of the direct current bus and the fine adjustment of output power. And setting a bus voltage recovery controller to detect the bus voltage of the system in real time, taking voltage deviation and duration as dual trigger thresholds, and recovering the bus voltage to be within an allowable range after the controller triggers. And setting an output power regulation controller for receiving and processing the power instruction of the decision layer, and synchronizing the triggering period and the instruction issuing period of the decision layer.
(3) Decision layer: as the "brain" of the whole energy control system, after the related operation information and load demand information of each power generation equipment are obtained (including the output voltage and current of the power generation equipment and each converter port and the expected power consumption condition of ship sailing), an optimized operation scheme of the hybrid power system is made through predictive optimization calculation (achieving the targets of high fuel utilization rate, low pollutant gas emission and the like), and the optimized operation scheme is transmitted to the middle layer through an information system.
Determining association relationships between layers
In the layered control architecture of power/energy, the time scale of the decision layer is the largest, and control instructions are intermittently given, but the highest priority of energy management is possessed, and the other two control layers can be directly guided and interfered; the main control object of the execution layer is each power generation device, the output power of each power generation device is controlled in a local continuous real-time mode, the time scale between two control instructions of the same power generation device is shortest, and the priority of the control instructions in the three control layers is lowest.
In general, sailing of a ship can be divided into several operating schemes, such as: docking and undocking, acceleration and deceleration, and cruising. The links between these operations are not arranged randomly, but follow a certain sailing law, for example: the watercraft cannot dock directly during acceleration and will not undock after cruising. The navigation rule can be used for scientifically predicting the operation condition of a period of time in the future and optimizing the management of the power/energy of the ship.
The power consumption operation of a ship can be classified into three types according to the characteristics of power consumption:
1. the power consumption is stable, and small fluctuation exists, such as: cruising, start-stop of low power service loads, etc.
2. The power consumption has a certain change, but is not repeated, such as: acceleration and deceleration, switching of high-power loads, and the like.
3. The power consumption is changed in a frequent and violent way, such as: docking and undocking, power positioning operations of special operation ships, and the like.
The three types of operation have different power change characteristics and maintenance time, and can be used for prejudging the power consumption operation by combining scientific prediction and operation information notification of equipment such as a car clock. For class 1 operation, the decision layer updates the control instructions every 15 min; for class 2 operation, the decision layer updates the control instruction every 5 min; for class 3 operations, the decision layer updates the control instructions every 3 minutes. For operations with shorter variation cycles, the intermediate layer may be diverted to control directly along with the execution layer.
It should be noted that the instruction update period is also related to the time of receiving and sending the information, and may be adjusted according to a specific embodiment. Meanwhile, the decision layer also transmits the instruction updating period to the middle layer, so that the middle layer can check whether the control instruction is updated in time.
Fig. 3 is a general control block diagram of hierarchical control, in which the relationship of control amounts between layers is crossed from the viewpoint of a control strategy. Fig. 4 is a flow chart of the execution of the hierarchical control, focusing on the complete control flow.
As shown in fig. 3 and 4, the decision layer inputs navigation history data and reads system operation information, and outputs the power generation equipment through optimization calculation and continuous correction decisionPower ofAnd sending the control command to an output power regulating controller of the middle layer.
When the decision layer has instruction update, the output power adjusting controller of the middle layer is synchronously triggered to respond to the power instruction of the decision layer. The controller performs feedback regulation on the output power of the power generation equipment, and the power deviation correction term Deltav generated by the controller p And outputting the power to an execution layer, and controlling each power generation device through the execution layer to realize the adjustment of output power. The bus voltage recovery controller of the middle layer detects the bus voltage of the system in real time, and when detecting that the bus voltage has larger deviation and is overlong in duration (refer to the amplitude and duration standard of GB or IEEE overvoltage/undervoltage), the triggering device sends a triggering signal (S=1) to the bus voltage recovery controller to correct the voltage deviation by the voltage deviation correction term Deltav v And outputting the voltage to an execution layer, and readjusting the output voltage of each power generation unit by using the execution layer, so that the bus voltage is finally restored to be within an allowable deviation range (different deviation ranges can be set according to the system power condition).
The execution layer realizes power coordination control among a plurality of parallel power generation devices through droop control and has a droop coefficient self-adjusting function. When the intermediate layer has instructions, the execution layer receives the instructions and changes the original sagging characteristic curve, and finally, the power flowing to the bus is changed by changing the output voltage of the port of the power generation equipment. Meanwhile, the execution layer can directly read local information to obtain the current use state of the power generation equipment, and when certain indexes reach a set threshold value, a droop coefficient self-adjusting function is triggered to adjust the droop coefficient of the power generation equipment.
In addition, in order to ensure the stable operation of the system, the decision layer also transmits the command update period to the middle layer, so that the middle layer can check whether the control command is updated in time. When the middle layer fails to receive the power instruction issued by the decision layer on time (taking normal communication delay into consideration) due to communication reasons, the whole ship power system is controlled by the middle layer and the execution layer in a combined way, so that the voltage stability of a bus of the system is maintained as a primary target, and the stable operation of the power system is ensured. And after waiting for communication recovery, the decision layer performs optimized power/energy management on the whole system level of the ship power system.
Specific embodiment of each control layer
The specific implementation method of each control layer is as follows:
execution layer (main control layer):
the power generating equipment in the hybrid power generation subsystem in the embodiment is connected to the direct current bus through the controllable power electronic converter, the power transmission quantity can be controlled by controlling the power electronic converter, and the final reflection forms are all the direct current voltage of the converter port and the power exchange on the direct current bus, so that the droop relation between the voltage and the power can be uniformly established. The voltage-power droop relationship in a conventional dc system is shown in (1).
wherein ,outputting a voltage reference value for the converter port at time t of the ith power generation equipment, +.>This is generally taken as the initial set point for the droop curve for the no-load output voltage of the converter. m is m i For the initial sag factor of the ith power plant, which is generally influenced by the capacity of the power plant, P oi (t) is the output power at the i-th converter t time, and can pass the port voltage measurement v at the i-th converter t time oi (t) and output current measurement i oi (t) multiplying.
It should be noted that: the voltage set point for the stationary type power plant sag curve is typically its rated output voltage, while the voltage set point for the rotating type power plant sag curve is typically an idle voltage (slightly above rated voltage).
Sag factor m i For characterizing the relationship between the i-th power plant output power and output voltage. As shown in fig. 5, in the dc system, for a stationary power plant, the output power thereof exhibits a two-quadrant characteristic (the first quadrant represents the discharge behavior, and the second quadrant represents the charge behavior); whereas for a rotating power plant its output power is only in the first quadrant.
The initial sag factor for two types of power plants can be calculated by the following formula:
wherein ,for the initial sag factor, deltaV, of the ith stationary-type power plant max For maximum permissible operating deviation of the dc bus, +.>Maximum charging power for an i-th stationary-class power plant,/->Maximum discharge power for an i-th stationary-class power plant, < >>For the initial sag factor of the i-th rotary power generation device,>maximum output power for the i-th rotary power generation device.
In practice, the sag factor of the power plant may be varied to achieve a wider range of functions, such as: increasing the droop factor for a genset (or an insufficient SOC energy storage device) in heavy load conditions is beneficial for overload (over-discharge) protection.
Therefore, in the hierarchical control architecture adopted by the invention, a droop coefficient self-adjusting function is added in the execution layer, and the execution layer needs to receive the intervention of the middle layer and the decision layer, so that the droop relation in (1) needs to be corrected. The modified form is shown in (4).
wherein ,m′i Improved droop coefficient, deltav, for the ith power plant v Voltage deviation correction term, deltav, output for bus voltage recovery controller p A power offset correction term is output for the output power adjustment controller.
k i Setting k for adjusting proportion of sagging coefficient of ith power generation equipment and related parameters of power generation equipment i Is 1.
Droop coefficient adjustment ratio of static power generation equipmentCan be obtained from (5).
wherein ,SOCi And (t) is the real-time charge state of the ith static type power generation equipment, and n is the amplified power for improving the regulation effect. When the SOC is within an appropriate range,maintaining an initial value; when SOC is lower than 0.3, < + >>Changing and acting on the first quadrant, inhibiting discharge behavior; when SOC is higher than 0.8, +.>Changing and acting on the second quadrant, suppressing the charging behavior.
Sag factor adjustment ratio of rotary power generation equipmentCan be obtained from (6).
wherein ,for the output power of the ith rotary power generation equipment at the economic working point, the value depends on the specific model and is generally 75-85% of rated power, P oi (t) is the real-time output power of the ith rotary power generation device,/and (c)>And n is the amplified power for the rated power of the ith rotary power generation equipment, and is used for improving the adjusting effect. When the current output power of the power plant is low, < > the power plant is low>Changing and reducing the droop coefficient to enable the power generation equipment to share more load power; when the current output power of the power plant is high, < > the power plant is low>Changing and increasing the droop factor, suppressing the tendency of power to increase again, and providing additional overload protection.
The following describes the specific implementation of droop control for stationary and rotary type power plants in conjunction with fig. 6-1 and 6-2.
1) Stationary power plant (energy storage device #1 as an example)
Step 1:collecting real-time output voltage v of converter port of energy storage device #1 o1 (t) and real-time output current i o1 (t) calculating the real-time output power P of the converter port after the low-pass filtering operation of the acquisition quantity o1 (t)。
Step 2: will output power P in real time o1 (t) obtaining the reference output voltage of the inverter as the input quantity of the droop controller according to the relation of the formula (4)And takes this as the output of the droop controller.
Step 3: will refer to the output voltageAnd outputting the voltage v in real time o1 The difference value of (t) is input into a voltage controller, and is regulated by proportional-integral (PI) to obtain a reference value of output current +.>
Step 4: will refer to the output currentWith the actual output current i of the energy storage device 1 The difference value of (t) is input into a current controller, and is regulated by proportion-integration (PI) and is subjected to PWM (pulse-Width modulation) link to obtain the duty ratio d 1 Triggering pulses of the DC/DC converter of (t).
2) Rotary power generation equipment
Step 1: in the same static type power generation equipment, the reference output voltage of the converter is calculated according to the sagging relation and the measured powerAnd are not described in detail herein.
Step 2: will refer to the output voltageAnd outputting the voltage v in real time o The difference value of (t) is input into a voltage controller and is regulated by proportional-integral (PI) to obtain q-axis reference output current +.>To maximize the unit power factor, the d-axis reference output current is set to +.>
Step 3: detecting an alternating current i at an output port of a generator a (t)、i b (t)、i c (t). Transforming it into abc-dq coordinates to obtain i d (t)、i q (t). The difference value between the d-axis current reference value and the q-axis current reference value and the actual value is input into a current feedforward decoupling controller to obtain d-axis voltage reference value and q-axis voltage reference value and />
Step 4: performing dq-alpha beta coordinate transformation to obtain v under alpha beta coordinate system α(t) and vβ (t). Obtaining switching signal S of three-phase PWM rectifier by Space Vector Pulse Width Modulation (SVPWM) 1 -S 6 。
(2) Intermediate layer (secondary control layer):
the sagging control operation of the layer can cause the voltage of the DC bus to deviate from the rated voltage, namely, the voltage deviation Deltav occurs bus The deviation value of the deviation value is equal to the sagging coefficient m 'of the power generation equipment' i And the actual output power P oi The correlation between (t) is shown in the formula (7).
Δv bus ＝m′ i ·P oi (t) (7)
As shown in fig. 7, the bus voltage recovery controller monitors the dc bus voltage v in real time dc (t) comparing it with the rated value v of the DC bus voltage dcn And comparing to obtain voltage deviation. When the amplitude sum of the voltage deviationWhen the deviation duration time is larger than the set threshold value, the bus voltage recovery controller is triggered to output a bus voltage correction term Deltav to the execution layer v . The original sag profile is translated by changing the initial voltage set point of the sag profile, and the power generation equipment is directly controlled by the execution layer to restore the bus voltage to be within an allowable range.
And an output power adjusting controller is also arranged in the middle layer and used for adjusting the output power of each power generation unit. When the decision layer has power instruction update, the output power adjusting controller synchronously triggers and receives the power instruction updated by the decision layerAnd sum it with the actual output power P of the current device oi (t) comparing. After obtaining the power deviation, the controller corrects the deviation, and the obtained power deviation correction term Deltav p Output to the droop controller of the execution layer. The output voltage of the ports of each power generation device is changed to influence the power flowing into the bus, and finally the aim of regulating the output power is achieved.
(3) Decision layer (top layer control layer):
the decision layer is responsible for adjusting the existing two-layer control system to meet the requirement of optimized, economical and efficient system operation. In the hybrid ship of the present embodiment, a rotary power generation device (diesel generator set) is the main power source. The economic cost and the pollutant gas emission of the ship during operation are both strongly related to the fuel utilization efficiency of the diesel engine, so that the ship needs to be used as an important target for the optimized operation of the system. In addition, the power distribution and coordination control during the mixed power supply of multiple energy sources also directly influence the power supply quality and the power supply stability of the whole ship, and the comprehensive management of a power generation party and a demand party is also needed.
In this embodiment, the decision layer receives local information of each power generation device in the system, including: rated output power P of diesel generator set Gn Minimum response time t G Climbing power limit P ramp External characteristic curve (for representing specific fuel consumption SFOC and output power P of diesel generator set o Between which are locatedIs a relationship of (2); maximum charge-discharge power of lithium battery packRated capacity E LIB_max State of charge SOC LIB (t) upper and lower limits of state of charge +.>Minimum response time t LIB The method comprises the steps of carrying out a first treatment on the surface of the Maximum charge-discharge power of super capacitor group +.>Rated capacity E SC_max State of charge SOC SC (t) upper and lower limits of state of charge +.>Output power P of each interface converter oi The case of (t) (from the port voltage v oi (t) and current i oi And (t) calculating. In addition, the decision layer also needs the history data of the ship voyage in order to obtain the estimated consumption power of voyage +.>
The relevant constraints formulated are as follows:
system power balance:
∑P oi (t)＝P load (8)
lithium battery pack constraints:
super capacitor group constraint:
and the decision layer utilizes the information to formulate an optimal operation scheme of the hybrid power generation system, and the decision layer performs the optimization according to the output power of each power generation device obtained by the optimization until the output power reaches the middle layer.
In the actual sailing process, the power consumed by the ship is influenced by the running sea conditions and weather conditions, and a certain difference exists between the actual power consumed and the predicted value, so that unbalanced power exists in the system. Because the generated power and the load power in the system are transmitted through the direct current bus, the unbalanced power of the system can be related to the direct current bus voltage by the formula (11).
wherein ,VC Is the voltage of two ends of a capacitor connected with the DC bus, namely the voltage v of the DC bus dc (t), C is the capacitance of the capacitor, I Source For the total output current of each power generation equipment, I Load The total current consumption for each load.
The equation (11) shows that when unbalanced power occurs in the system, the unbalanced power is reflected on the increase and decrease of the direct current bus voltage, so that the bus voltage recovery controller in the middle layer can play a role in maintaining the power balance of the system in a certain range while recovering the bus voltage, and the power scheduling deviation of the decision layer can be relieved to a certain extent.
The invention provides a power/energy management method of a hybrid power ship based on layered control, which organically combines the advantages of centralized control and decentralized control, reduces the requirement of the centralized control on communication and avoids the defects of the centralized control on the communication; meanwhile, compared with decentralized control, the information of the power system can be utilized more comprehensively, the optimization of the equipment level and the full system level is considered, and support and technical foundation are provided for realizing the advanced functions of ship energy management. The architecture uses a communication network but is not entirely dependent; when the system communication is blocked/delayed or the local/global communication is failed, the lower control layers (the execution layer and the middle layer) independently work to complete corresponding control tasks, so that the optimal and stable running power/energy management of the non-whole system level of the ship power system can be maintained.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention, and are intended to be included within the scope of the appended claims and description.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910975575.8A CN110690730B (en) | 2019-10-15 | 2019-10-15 | Power and energy control method for hybrid power ship |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910975575.8A CN110690730B (en) | 2019-10-15 | 2019-10-15 | Power and energy control method for hybrid power ship |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110690730A CN110690730A (en) | 2020-01-14 |
| CN110690730B true CN110690730B (en) | 2023-09-29 |
Family
ID=69112803
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910975575.8A Active CN110690730B (en) | 2019-10-15 | 2019-10-15 | Power and energy control method for hybrid power ship |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110690730B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111392017A (en) * | 2020-04-17 | 2020-07-10 | 武汉理工大学 | Multi-energy management system of diesel-electric hybrid power ship |
| CN111907680B (en) * | 2020-09-07 | 2025-01-14 | 锡瑞迪船用动力系统(上海)有限公司 | A hybrid power ship energy efficiency control system and method |
| CN114498795A (en) * | 2020-11-12 | 2022-05-13 | 中国科学院沈阳自动化研究所 | An energy management method for a marine DC hybrid power system |
| CN113306694A (en) * | 2021-06-17 | 2021-08-27 | 福建水利电力职业技术学院 | Water-wind-light combined type marine power generation and storage system |
| CN113525657B (en) * | 2021-07-08 | 2022-08-02 | 哈尔滨工程大学 | Ship hybrid power hybrid model prediction control method based on hybrid logic dynamic theory |
| CN113525656B (en) * | 2021-07-08 | 2022-10-28 | 哈尔滨工程大学 | Gas-electric hybrid power ship energy distribution method based on propeller rotating speed closed loop |
| CN113471954A (en) * | 2021-08-10 | 2021-10-01 | 上海空间电源研究所 | Novel space satellite power supply system composite bus topological structure |
| CN114435575B (en) * | 2022-03-01 | 2023-04-11 | 深圳国氢新能源科技有限公司 | Ship hybrid power system, energy management control method, equipment and storage medium |
| CN115214865B (en) * | 2022-07-29 | 2024-03-01 | 中国船舶重工集团公司第七0四研究所 | Ship hybrid power system and energy management method thereof |
| CN116154749A (en) * | 2023-01-06 | 2023-05-23 | 西北工业大学 | Layering control method for high average peak ratio hybrid energy system of multi-motor aircraft |
| CN116198687B (en) * | 2023-04-13 | 2025-09-30 | 武汉理工大学 | A hierarchical distributed control method and system for a multi-energy ship hybrid power system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104242337A (en) * | 2014-08-14 | 2014-12-24 | 广东易事特电源股份有限公司 | Real-time coordination and control method of photovoltaic micro-grid system |
| WO2015075923A1 (en) * | 2013-11-20 | 2015-05-28 | 川崎重工業株式会社 | Power conversion device |
| CN106849052A (en) * | 2017-03-29 | 2017-06-13 | 天津大学 | Direct-current grid group's power coordination control method |
| CN108039718A (en) * | 2017-11-17 | 2018-05-15 | 中国电力科学研究院有限公司 | A kind of improved flexible direct current voltage control method and system |
| CN108418245A (en) * | 2018-03-09 | 2018-08-17 | 天津大学 | A Simplified Constant Power Control Method for Tie Lines of DC Microgrid |
| CN108832612A (en) * | 2018-07-02 | 2018-11-16 | 东北大学 | A DC microgrid control method and system based on layered management |
-
2019
- 2019-10-15 CN CN201910975575.8A patent/CN110690730B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015075923A1 (en) * | 2013-11-20 | 2015-05-28 | 川崎重工業株式会社 | Power conversion device |
| CN104242337A (en) * | 2014-08-14 | 2014-12-24 | 广东易事特电源股份有限公司 | Real-time coordination and control method of photovoltaic micro-grid system |
| CN106849052A (en) * | 2017-03-29 | 2017-06-13 | 天津大学 | Direct-current grid group's power coordination control method |
| CN108039718A (en) * | 2017-11-17 | 2018-05-15 | 中国电力科学研究院有限公司 | A kind of improved flexible direct current voltage control method and system |
| CN108418245A (en) * | 2018-03-09 | 2018-08-17 | 天津大学 | A Simplified Constant Power Control Method for Tie Lines of DC Microgrid |
| CN108832612A (en) * | 2018-07-02 | 2018-11-16 | 东北大学 | A DC microgrid control method and system based on layered management |
Non-Patent Citations (2)
| Title |
|---|
| 直流微电网关键技术研究综述;李霞 等;《中国电机工程学报》;20160131;第36卷(第1期);全文 * |
| 自治直流微电网分层控制策略;邱摇摇等;《电力建设》;20161031(第10期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110690730A (en) | 2020-01-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110690730B (en) | Power and energy control method for hybrid power ship | |
| Ghimire et al. | Shipboard electric power conversion: System architecture, applications, control, and challenges [technology leaders] | |
| He et al. | A flexible power control strategy for hybrid AC/DC zones of shipboard power system with distributed energy storages | |
| Mutarraf et al. | Adaptive power management of hierarchical controlled hybrid shipboard microgrids | |
| KR102627677B1 (en) | Dynamic hybrid control | |
| CN110224444B (en) | Multi-time scale coordination control method for island microgrid | |
| Shahzad et al. | Model predictive control strategies in microgrids: A concise revisit | |
| CN104015912B (en) | Ship hybrid power control system and control method | |
| JP4306760B2 (en) | Distributed power supply | |
| CN110457859B (en) | Optimal control method for hybrid electric ship propulsion system | |
| CN110110422B (en) | Ship multi-power-supply composite utilization minimum fuel consumption rate optimization method | |
| WO2015001800A1 (en) | Microgrid control device and control method therefor | |
| Kumar et al. | Improved fuel-use efficiency in diesel–electric tugboats with an asynchronous power generating unit | |
| Othman et al. | Hybrid shipboard microgrids: System architectures and energy management aspects | |
| CN107269454A (en) | Suitable for the power generation with marine energy system of offshore platform frequency conversion drive trepan | |
| Dinh et al. | Optimal energy management for hybrid electric dynamic positioning vessels | |
| Budashko et al. | Conceptualization of research of power hybrid electric power complexes | |
| Özdamar et al. | Design and Implementation of Power Management Algorithm for Efficient Operation of Fishing Vessel with Battery Integrated Hybrid Shaft Generator/Motor System | |
| CN107681649B (en) | A method for controlling the voltage stability of DC microgrid busbars | |
| CN119341124A (en) | Topological structure, optimization dispatching method, device, medium and equipment of port shore power DC system with overcapacity | |
| CN117895551A (en) | A shore power energy router system | |
| Liu et al. | Optimal transient power sharing method for shipboard MVDC System based on segmented variable step dynamic programming | |
| CN115800311B (en) | Island wind-solar-diesel storage power supply system and control method thereof | |
| Patsios et al. | Discussion on adopting intelligent power management and control techniques in integrated power systems of all-electric ships | |
| CN113472005B (en) | Ship shore power system with distributed power supply and working method thereof |
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 | ||
| GR01 | Patent grant |