WO2024093334A1 - 一种控制方法、新能源变换器和并网电力系统 - Google Patents

一种控制方法、新能源变换器和并网电力系统 Download PDF

Info

Publication number
WO2024093334A1
WO2024093334A1 PCT/CN2023/105525 CN2023105525W WO2024093334A1 WO 2024093334 A1 WO2024093334 A1 WO 2024093334A1 CN 2023105525 W CN2023105525 W CN 2023105525W WO 2024093334 A1 WO2024093334 A1 WO 2024093334A1
Authority
WO
WIPO (PCT)
Prior art keywords
power
voltage
conversion circuit
phase
active power
Prior art date
Application number
PCT/CN2023/105525
Other languages
English (en)
French (fr)
Inventor
屈子森
赵明权
王硕
辛凯
刘云峰
Original Assignee
华为数字能源技术有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 华为数字能源技术有限公司 filed Critical 华为数字能源技术有限公司
Publication of WO2024093334A1 publication Critical patent/WO2024093334A1/zh

Links

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
    • H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
    • 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
    • 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
    • H02J3/48—Controlling the sharing of the in-phase component
    • 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
    • H02J3/50—Controlling the sharing of the out-of-phase component
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/56—Power conversion systems, e.g. maximum power point trackers

Definitions

  • the present invention relates to the field of power electronics technology, and in particular to a control method, a new energy converter and a grid-connected power system.
  • Clean energy includes solar energy, wind energy, hydropower, tidal energy, etc.
  • clean energy cannot be used directly, but can be converted into electrical energy for human use.
  • photovoltaic power generation systems convert solar energy into electrical energy
  • hydropower generation systems convert water energy into electrical energy
  • wind power generation systems convert wind energy into electrical energy, and other conversion methods.
  • a control method, a new energy converter and a grid-connected power system are provided in the embodiments of the present application.
  • the new energy converter adjusts the active power at the output end in real time through units such as command adjustment, inertia control, and forward control to achieve active power support for frequency and active power support for phase.
  • the controller adjusts the phase of the active power, and cooperates with units such as forward control to provide frequency and phase support characteristics in the closed-loop control of active power and frequency; the controller adjusts the voltage parameters at the output end of the power electronic converter through control loop adjustment according to the active power after phase adjustment; in addition, when the controller receives the power command, it adjusts the power command, and the corresponding active power adjustment value is processed by difference with the active power after phase adjustment to obtain the power difference.
  • the controller can directly control the voltage parameters at the output end of the conversion circuit according to the power difference, thereby improving the speed of the command response of the conversion circuit.
  • the embodiment of the present application provides a network control method for a new energy converter, which is applied to the new energy converter including a conversion circuit and a controller, wherein the input end of the conversion circuit is used to connect to a DC source, and the output end is used to connect to an AC system, and the method includes: the controller is used to control the conversion circuit to output active power, and when the voltage frequency of the AC system fluctuates, the phase of the active power is delayed; according to the active power after the delayed phase, the voltage parameter of the output end of the conversion circuit is controlled so that the conversion circuit outputs active power with inertia support.
  • the output of the generator set and the load of the power system are changing all the time, which makes it difficult for the generator set to rotate at a constant speed.
  • the frequency of the power system will fluctuate due to the power imbalance between the generator set and the load, thereby causing the frequency to fluctuate.
  • the controller after obtaining the active power feedback value of the output end of the conversion circuit, the controller adjusts the phase of the active power feedback value, and can provide an inertia support feature in the closed-loop control of active power, frequency, and phase.
  • the controller quickly controls the voltage parameters of the output end of the conversion circuit according to the active power after the phase adjustment; in particular, the voltage parameters of the output end of the conversion circuit can be quickly adjusted without affecting the inertia support feature of the inverter.
  • the before controlling the voltage parameters of the output end of the conversion circuit according to the active power after the delayed phase it also includes: receiving a power instruction, the power instruction is used to control the voltage parameters of the output end of the conversion circuit; controlling the voltage parameters of the output end of the conversion circuit according to the active power after the delayed phase, including: subtracting the active power corresponding to the power instruction from the active power after the delayed phase to obtain a power difference; and controlling the voltage parameters of the output end of the conversion circuit according to the power difference.
  • the controller after receiving the power command, the controller obtains the power difference by subtracting the active power corresponding to the power command from the active power after phase adjustment, and then quickly controls the voltage parameters of the output end of the conversion circuit. Without affecting the inertia support characteristics of the inverter, the voltage at the output end of the conversion circuit can be quickly adjusted, thereby improving the speed of the controller's command response.
  • after receiving the power instruction it also includes: converting the active power corresponding to the power instruction into a given power; when the output voltage at the output end of the conversion circuit is stable, the value of the given power is equal to the active power after the delayed phase; subtracting the active power corresponding to the power instruction from the active power after the delayed phase to obtain a power difference, including: subtracting the given power from the active power after the delayed phase to obtain a power difference.
  • the controller After receiving the power instruction, the controller converts the active power corresponding to the power instruction into a given power, so that the value of the set power is the same as the active power after phase adjustment when the output voltage of the output end of the conversion circuit is stable. At this time, the power difference is zero, and when the output voltage of the output end of the conversion circuit is stable, the controller does not need to adjust the output voltage of the output end of the conversion circuit.
  • the voltage parameter includes the frequency of the voltage
  • the voltage parameter of the output end of the conversion circuit is controlled according to the power difference, including: utilizing the relationship between the power and frequency of the synchronous motor to convert the power difference into the frequency of the voltage.
  • the controller converts the frequency of the voltage according to the power difference, so as to adjust the frequency of the output voltage at the output end of the conversion circuit.
  • the voltage parameters also include the phase of the voltage.
  • the voltage parameters at the output end of the conversion circuit are controlled, including: integrating the angular velocity of the voltage to obtain the phase of the voltage; the frequency of the voltage is determined according to the power difference, and the angular velocity of the voltage is determined according to the frequency of the voltage.
  • the controller integrates the angular velocity of the voltage to obtain the phase of the voltage, thereby adjusting the phase of the output voltage at the output end of the conversion circuit.
  • the voltage parameters also include the amplitude of the voltage.
  • the voltage parameters at the output end of the conversion circuit are controlled, including: controlling the amplitude and phase of the voltage according to the reactive power rated value, the actual reactive power value, the angular velocity of the voltage, the phase of the voltage, the amplitude rated value and the actual amplitude value; the reactive power is determined according to the output voltage signal and the output current signal, the frequency of the voltage is determined according to the power difference, the angular velocity of the voltage is determined according to the frequency of the voltage, and the phase of the voltage is determined according to the angular velocity of the voltage.
  • the controller controls the amplitude of the voltage according to the reactive power, the angular velocity of the voltage, the phase of the voltage, the amplitude rating and the reactive power rating, so as to adjust the phase of the output voltage at the output end of the conversion circuit.
  • the method further includes: generating a trigger signal according to the voltage parameter, the trigger signal being used to trigger the power electronic device inside the conversion circuit to turn on and off, and further adjusting the voltage parameter of the output end of the conversion circuit.
  • an embodiment of the present application provides a new energy converter, including a conversion circuit and a controller, the controller being used to control the conversion circuit to output active power and delay the phase of the active power when the voltage frequency of the AC system fluctuates; based on the active power after the delayed phase, the voltage parameters of the output end of the conversion circuit are controlled so that the conversion circuit outputs active power with frequency and phase support.
  • the controller is further used to receive a power instruction, the power instruction is used to control the voltage parameter of the output end of the conversion circuit; the active power corresponding to the power instruction is processed by difference with the active power after phase adjustment to obtain a power difference; according to the power difference, the voltage parameter of the output end of the conversion circuit is controlled.
  • the new energy converter refers to a commonly used power electronic converter, such as an inverter, a rectifier, a modular multilevel converter or other converter, or a bidirectional converter.
  • the controller is also used to convert the active power corresponding to the power instruction into a given power; when the output voltage at the output end of the conversion circuit is stable, the value of the given power is equal to the active power after the delayed phase; the given power is subtracted from the active power after the delayed phase to obtain the power difference.
  • the voltage parameter includes the frequency of the voltage
  • the controller is specifically configured to convert the power difference into the frequency of the voltage by utilizing the relationship between the power and the frequency of the synchronous motor.
  • the voltage parameter also includes the phase of the voltage.
  • the controller is specifically used to integrate the angular velocity of the voltage to obtain the phase of the voltage.
  • the frequency of the voltage is determined according to the power difference, and the angular velocity of the voltage is determined according to the frequency of the voltage.
  • the amplitude of the voltage is controlled based on the reactive power rated value, the actual reactive power value, the angular velocity of the voltage, the phase of the voltage, the amplitude rated value and the amplitude actual value; the reactive power is determined based on the output voltage signal and the output current signal, the frequency of the voltage is determined based on the power difference, the angular velocity of the voltage is determined based on the frequency of the voltage, and the phase of the voltage is determined based on the angular velocity of the voltage.
  • the controller is further used to generate a trigger signal according to the voltage parameter, and the trigger signal is used to trigger the power electronic device inside the conversion circuit to adjust the voltage parameter of the output end of the conversion circuit.
  • an embodiment of the present application provides a grid-connected power system, comprising: a new energy component, and at least one new energy converter that may be realized in the second aspect, wherein the input end of the new energy converter is connected to the new energy component, or is indirectly connected to the new energy component through a DC converter, or is connected to other energy storage devices, and the output end of the new energy converter is used to connect to a power grid or a load, and the converter is used to convert the DC power of the new energy component or the DC power output by the DC converter into the AC power of the power grid, or to convert the AC power of the power grid into DC power.
  • an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon.
  • the computer program is executed in a computer, the computer is caused to execute each possible implementation embodiment of the first aspect.
  • an embodiment of the present application provides a computer program product, characterized in that the computer program product stores instructions, which, when executed by a computer, enable the computer to implement various possible implementation embodiments of the first aspect.
  • FIG1 is a schematic diagram of the architecture of a grid-connected power system in the prior art
  • FIG. 2( a ) is a schematic diagram of a process in which a networking control unit executes a command response in the prior art
  • FIG2( b ) is a schematic diagram of a process in which a meshing control unit executes a frequency and phase support response in the prior art
  • FIG3 is a schematic diagram of the architecture of a networking control unit in the prior art
  • FIG4 is a schematic diagram of the architecture of a networking control unit in the prior art
  • FIG5 is a schematic diagram of the architecture of a controller provided in an embodiment of the present application.
  • FIG6 is a flow chart of a control method provided in an embodiment of the present application.
  • a and/or B in this article is a description of the association relationship of associated objects, indicating that there can be three relationships.
  • a and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone.
  • the symbol "/" in this article indicates that the associated objects are in an or relationship, for example, A/B means A or B.
  • first and second in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of the objects.
  • a first response message and a second response message are used to distinguish different response messages rather than to describe a specific order of the response messages.
  • words such as “exemplary” or “for example” are used to indicate examples, illustrations or descriptions. Any embodiment or design described as “exemplary” or “for example” in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as “exemplary” or “for example” is intended to present related concepts in a specific way.
  • multiple means two or more than two.
  • multiple processing units refer to two or more processing units, etc.; multiple elements refer to two or more elements, etc.
  • photovoltaic power generation systems, hydropower generation systems, wind power generation systems, backup power systems and other external power systems are incorporated into the power grid system, they generally need to be connected in series with the power grid system using an inverter.
  • the inverter can adjust the voltage parameters of the external power system, such as the voltage frequency, voltage phase and voltage amplitude, so that the voltage parameters of the external power system are the same as those of the national power supply system.
  • Existing inverters can be divided into grid-following control inverters, grid-forming control inverters and other types of inverters according to different control logics.
  • the grid-following control inverter uses a phase-locked loop to make the voltage parameters of the external power supply system the same as the voltage parameters of the national power supply system.
  • the grid-forming control inverter uses power control to make the voltage parameters of the external power supply system the same as the voltage parameters of the national power supply system.
  • the grid-type control inverter When the grid-type control inverter integrates the external power system into the national power system, the grid-type control inverter will show the characteristics of low inertia or no inertia. If a large-scale external power system is integrated into the power grid system, the inertia and system strength of the power grid system will be reduced. However, the grid-type control inverter will not reduce the inertia and system strength of the power grid system. Therefore, the grid-type control inverter has more advantages than the grid-type control inverter.
  • FIG1 is a schematic diagram of the architecture of a grid-connected power system in the prior art.
  • the grid-connected power system 100 includes a power system 110, an inverter 120, and an external power system 130.
  • the external power system 130 is incorporated into the power system 110 through the inverter 120.
  • the grid-connected power system 100 may include other components, such as transformers, inductors, power connection lines, etc., which are not limited in this application.
  • the inverter 120 includes a bidirectional direct current/alternating current (DC/AC) conversion circuit 121 and a meshing control unit 122.
  • the input end of the bidirectional DC/AC conversion circuit 121 is electrically connected to the external power supply system 130.
  • the output end of the bidirectional DC/AC conversion circuit 121 is electrically connected to the power system 110.
  • the bidirectional DC/AC conversion circuit 121 converts the direct current of the external power supply system 130 into alternating current and inputs it into the power system 110.
  • the meshing control unit 122 is coupled to the bidirectional DC/AC conversion circuit 121, and is used to receive the output voltage signal and the output current signal of the output end of the bidirectional DC/AC conversion circuit 121, and the input voltage signal and the input current signal of the input end.
  • the output voltage signal may be the DC voltage of the bidirectional DC/AC conversion circuit 121.
  • the output voltage signal may be the AC voltage of the bidirectional DC/AC conversion circuit 121.
  • the network control unit 122 After receiving the output voltage signal and the output current signal of the bidirectional DC/AC conversion circuit 121, the network control unit 122 adjusts the voltage parameters of the output end of the bidirectional DC/AC conversion circuit 121 so that the voltage parameters of the output end of the bidirectional DC/AC conversion circuit 121 are consistent with the power system.
  • the voltage parameters of 110 are the same.
  • the voltage parameters may refer to the frequency of the voltage, the phase of the voltage and the amplitude of the voltage.
  • FIG2(a) is a schematic diagram of the process of executing a command response by a networking control unit in the prior art.
  • the networking control unit 122 is divided into a networking control synchronization unit 1221, a phase control unit 1222, an amplitude control unit 1223 and a preprocessing unit 1224 according to the execution function.
  • the preprocessing unit 1224 receives the output voltage signal and the output current signal of the output end of the bidirectional DC/AC conversion circuit 121, and calculates the active power Pe.
  • the networking control synchronization unit 1221 can receive the active power Pref corresponding to the power instruction sent externally and the active power Pe of the preprocessing unit 1224.
  • the networking control synchronization unit 1221 can determine the relationship between power and frequency by analogy with the nonlinear positive relationship between the power and frequency of the synchronous motor.
  • the phase control unit 1222 After receiving the angular velocity ⁇ syn of the voltage, the phase control unit 1222 integrates the angular velocity ⁇ syn of the voltage to obtain the phase ⁇ syn of the voltage.
  • the amplitude control unit 1223 receives parameters such as the angular velocity ⁇ syn of the voltage and the phase ⁇ syn of the voltage, and can calculate the amplitude Ve of the voltage, and send a control instruction to the bidirectional DC/AC conversion circuit 121 to allow the bidirectional DC/AC conversion circuit 121 to adjust the voltage parameters of the output voltage at the output end.
  • the networking control synchronization unit 1221 receives the power command sent from the outside.
  • the active power Pref corresponding to the power command received by the networking control unit 122 changes, the active power Pe at the output end of the bidirectional DC/AC conversion circuit 121 will change accordingly.
  • the networking control synchronization unit 1221 quickly converts the active power Pref into the angular velocity ⁇ syn of the voltage, so that the output power of the bidirectional DC/AC conversion circuit 121 can quickly respond to the power command.
  • the meshing control synchronization unit 1221 receives the active power Pe from the preprocessing unit 1224.
  • the meshing control synchronization unit 1221 slowly converts the active power Pe into the angular velocity ⁇ syn of the voltage, so as to avoid the inverter 120 from quickly adjusting the voltage parameters of the output voltage at the output end, and reduce the frequency and phase support characteristics of the power system 110.
  • the conversion speed of the networking control synchronization unit 1221 is opposite. If the conversion speed of the networking control synchronization unit 1221 is relatively fast, the frequency and phase support characteristics of the inverter 100 will be weakened. If the conversion speed of the networking control synchronization unit 1221 is relatively slow, the speed at which the inverter 120 responds to the power command is reduced. Therefore, the existing networking control unit 122 cannot solve the contradiction between the power command response and the frequency and phase support response.
  • the grid-forming control unit 122 may further include a parameter adaptive adjustment unit 1225.
  • the parameter adaptive adjustment unit 1225 is coupled to the grid-forming control synchronization unit 1221.
  • the networking control synchronization unit 1221 executes the power command response.
  • the networking control unit 122 receives the active power Pref corresponding to the power command, it sends the active power Pref to the parameter adaptive adjustment unit 1225.
  • the parameter adaptive adjustment unit 1225 generates control parameters according to the active power Pref, the control environment information of the networking control unit 122, and other state quantities.
  • the networking control synchronization unit 1221 can autonomously adjust the speed of converting the active power Pref into the angular velocity ⁇ syn of the voltage according to the control parameters, which can improve the speed of the inverter 100 responding to the power command and reduce the frequency and phase support characteristics of the inverter 100.
  • the preprocessing unit 1224 sends the active power Pe to the meshing control unit 122.
  • the meshing control unit 122 receives the change in active power Pe.
  • the meshing control unit 122 sends the active power Pe to the parameter adaptive adjustment unit 1225.
  • the parameter adaptive adjustment unit 1225 generates control parameters according to the active power Pe, the control environment information of the meshing control unit 122, and other state quantities.
  • the meshing control synchronization unit 1221 can reversely and autonomously adjust the speed of converting the angular velocity ⁇ of the active power into the angular velocity ⁇ syn of the voltage according to the control parameters, which can improve the frequency and phase support characteristics of the inverter 100, but reduce the speed of the inverter 100 in responding to power instructions.
  • the networking control unit 122 adds a technical path based on parameter adaptation, and uses the control parameters generated by the parameter adaptive adjustment unit 1225 according to the active power and environmental factors to adjust the conversion speed of the networking control synchronization unit 1221.
  • the control parameters are in a dynamically changing state, so that the active power conversion speed, frequency, phase support characteristics and other characteristics of the inverter 100 will change with the change of the control parameters, thereby reducing the stability of the inverter 100.
  • the control parameters generated by the parameter adaptive adjustment unit 1225 can allow the networking control synchronization unit 1221 to autonomously adjust the conversion speed within a certain numerical range. However, under certain working conditions, after the control parameters exceed a certain numerical range, it is difficult for the networking control synchronization unit 1221 to autonomously adjust the conversion speed.
  • the grid-type control unit 122 may further include a command fast compensation unit 1226.
  • the output end of the command fast compensation unit 1226 is respectively coupled to the phase control unit 1222 and the amplitude control unit 1223.
  • the inverter 120 After receiving the power instruction, the inverter 120 sends the active power Pref corresponding to the power instruction to the network control synchronization unit 1221 and the instruction fast compensation unit 1226. After receiving the power instruction sent by the outside world, the network control synchronization unit 1221 executes the power instruction response.
  • the instruction fast compensation unit 1226 generates parameters such as frequency compensation and phase compensation according to the change in the instruction power corresponding to the power instruction and other variables. After the network control synchronization unit 1221 converts the active power into the speed of the angular velocity ⁇ syn of the voltage, it inputs it to the phase control unit 1222.
  • the phase control unit 1222 can perform phase compensation according to the phase compensation amount of the instruction fast compensation unit 1226, or the amplitude control unit 1223 can perform frequency compensation according to the frequency compensation amount of the instruction fast compensation unit 1226, etc., which can improve the speed of the inverter 100 responding to the power instruction. However, the frequency and phase support characteristics of the inverter 100 will be weakened.
  • the embodiments of the present application provide a new energy converter, a control method and a grid-connected power system.
  • FIG5 is a schematic diagram of the structure of a new energy converter provided in an embodiment of the present application.
  • the new energy converter 500 includes a conversion circuit 510 and a controller 520.
  • one end of the new energy converter 500 is electrically connected to the external power supply system, and the other end of the converter 500 is electrically connected to the power system.
  • the new energy converter 500 may be an inverter, a rectifier, a modular multi-level converter or other converters. In other embodiments, the new energy converter 500 may be a bidirectional converter.
  • the external power supply system may be a backup power supply, a photovoltaic power generation system, a hydroelectric power generation system, a wind power generation system or other power supply systems.
  • the power system may be a power grid system, a home power grid, a business power grid, or other power systems.
  • the conversion circuit 510 includes a bidirectional DC/AC conversion circuit for converting AC power into DC power, or converting DC power into AC power.
  • the voltage of the external power system is DC power
  • the voltage of the power system is AC power.
  • the conversion circuit 510 converts the DC power of the external power system into AC power of a set voltage value.
  • the conversion circuit 510 can be other types of conversion circuits, which are not limited in this application.
  • the controller 520 may be a digital signal processing (DSP) unit, a field programmable gate array (FPGA), a microcontroller unit (MCU) or other devices with computing and control functions.
  • DSP digital signal processing
  • FPGA field programmable gate array
  • MCU microcontroller unit
  • the controller 520 After receiving the power instruction of the external input, the controller 520 adjusts the voltage parameters of the output voltage of the output end of the conversion circuit 510 according to the active power corresponding to the power instruction, the output voltage signal U1 and the output current signal I1 of the output end of the conversion circuit 510, and the input voltage signal U2 and the input current signal I2 of the input end.
  • the voltage parameters may refer to the frequency fsyn of the voltage, the phase ⁇ syn of the voltage and the amplitude Ve of the voltage.
  • the controller 520 can be divided into a pre-processing unit 521, an inertia control unit 522, an instruction adjustment unit 523, a subtractor 524, a forward control unit 525, a phase control unit 526, an amplitude control unit 527 and a modulation unit 528 according to the functions to be performed.
  • the pre-processing unit 521, the inertia control unit 522, the instruction adjustment unit 523, the subtractor 524, the forward control unit 525, the phase control unit 526, the amplitude control unit 527 and the modulation unit 528 can all be implemented by software, or by hardware, or by a combination of software and hardware.
  • the preprocessing unit 521 is used to receive the output voltage signal U1 and the output current signal I1 of the output end of the conversion circuit 510.
  • the preprocessing unit 521 is also used to calculate the active power Pe and the reactive power Qe according to the output voltage signal U1 and the output current signal I1, and input the active power Pe to the inertia control unit 522, and input the reactive power Qe, the input voltage signal U2 and the output voltage signal U1 to the amplitude control unit 527.
  • the active power Pe and the reactive power Qe can be either average power or instantaneous power.
  • the active power Pe refers to the AC power energy actually generated or consumed per unit time, which is the average power in the cycle;
  • the reactive power Qe refers to the electric field or magnetic field in an AC circuit with reactance absorbing energy from the power supply during a part of a cycle and releasing energy during another part of a cycle.
  • the average power is zero in the entire cycle, but the energy is continuously exchanged between the power supply and the reactance element (capacitor, inductor).
  • the maximum value of the exchange rate is the reactive power Qe.
  • its magnitude is equal to the product of the instantaneous voltage and the instantaneous value of the current.
  • the instantaneous power of alternating current is not a constant value.
  • the average value of instantaneous power within a cycle is called active power. Therefore, active power is also called average power.
  • the conversion circuit 510 also includes a sampling module.
  • the sampling module samples the output voltage and output current of the output end to obtain the output voltage and output current.
  • the sampling module converts the output voltage and output current into digital signals to obtain the output voltage signal U1 and the output current signal I1 , and inputs the output voltage signal U1 and the output current signal I1 into the controller 520.
  • the sampling module samples the input voltage and input current of the input end to obtain the input voltage and input current.
  • the sampling module converts the input voltage and input current into digital signals to obtain the input voltage signal U2 and the input current signal I2 , and inputs the input voltage signal U2 and the input current signal I2 into the controller 520.
  • the conversion circuit 510 may be a bidirectional conversion circuit.
  • the input end of the conversion circuit 510 is an external power supply system, and the output end of the conversion circuit 510 is a power system.
  • the output voltage is an AC voltage
  • the output current is an AC current
  • the input voltage is a DC voltage
  • the input current is a DC current
  • the input end of the conversion circuit 510 is a power system
  • the output end of the conversion circuit 510 is an external power system.
  • the output voltage is a DC voltage
  • the output current is a DC current
  • the input voltage is an AC voltage
  • the input current is an AC current.
  • the inertia control unit 522 can be a combination of one or more functions such as a proportional function, an integral equation, a first-order low-pass filter, and a multi-order low-pass filter.
  • the inertia control unit 522 can transform the phase of the active power Pe to obtain the active power Peic after the delayed phase.
  • the inertia control unit 522 transforms the phase of the active power Pe, the amplitude of the active power Pe changes.
  • the inertia control unit 522 transforms the amplitude and phase of the active power Pe, so that the phase of the active power Pe is delayed and the amplitude of the active power Pe changes. In the closed-loop control of active power and frequency, the inertia control unit 522 provides frequency and phase support characteristics for the new energy converter 500.
  • the inertia control of the inertia control unit 522 can be equivalent to a first-order low-pass filter of the swing equation. After the active power Pe is input to the first-order low-pass filter, the first-order low-pass filter can convert the amplitude and phase of the active power Pe according to the stability parameter 1/K D conversion, so that the phase of the active power Pe is delayed and the amplitude of the active power Pe changes.
  • the instruction adjustment unit 523 can be a combination of one or more functions such as proportional function, integral equation, rotor motion equation, first-order low-pass filter, multi-order low-pass filter, etc.
  • the instruction adjustment unit 523 is used to process the active power Pref corresponding to the input power instruction, and convert the active power Pref corresponding to the power instruction into a given power Prefa.
  • the control system is in a stable state.
  • the given power Prefa output by the instruction adjustment unit 523 is the same as the active power Peic after the delayed phase output by the inertia control unit 522.
  • the instruction adjustment unit 523 is a proportional function, and the instruction adjustment unit 523 divides the active power Pref corresponding to the power instruction by a set proportional value to obtain a given power Prefa.
  • the instruction adjustment unit 523 is a first-order low-pass filter, and the instruction adjustment unit 523 performs filtering processing on the active power Pref corresponding to the power instruction, and converts the active power Pref corresponding to the power instruction into a given power Prefa.
  • the subtractor 524 is used to receive the given power Prefa output by the instruction adjustment unit 523 and the active power Peic after phase delay output by the inertia control unit, and perform difference processing on the given power Prefa and the active power Peic after phase delay to obtain a power difference value ⁇ P.
  • the forward control unit 525 can be a combination of one or more functions such as a proportional function, a differential equation, a low-pass filter, a high-pass filter, a lead/lag correction function, etc.
  • the forward control unit 525 can determine the relationship between power and frequency by analogy with the nonlinear positive relationship between the power and frequency of the synchronous motor. After receiving the power difference ⁇ P, the forward control unit 525 uses the relationship between power and frequency to quickly convert the power difference ⁇ P into the angular velocity ⁇ syn of the voltage, and outputs the angular velocity ⁇ syn of the voltage to the phase control unit 526, the amplitude control unit 527 and the modulation unit 528.
  • the forward control unit 525 is a combination of a proportional function, a differential equation and a low-pass filter.
  • the forward control unit 525 divides the power difference ⁇ P by a set proportional value, performs differentiation and filtering, and obtains the angular velocity ⁇ syn of the voltage corresponding to the power difference ⁇ P.
  • the phase control unit 526 may be an integrator or a combination of an integrator and other devices. Upon receiving the angular velocity ⁇ syn of the voltage, the phase control unit 526 integrates the angular velocity ⁇ syn of the voltage to obtain the phase ⁇ syn of the voltage, and outputs the phase ⁇ syn of the voltage to the amplitude control unit 527 and the modulation unit 528.
  • the amplitude control unit 527 may be a combination of one or more functions such as a proportional function, an integral equation, a proportional integral equation, etc. After receiving the reactive power Qe, the input voltage signal U 2 , the output voltage signal U 1 , the angular velocity ⁇ syn of the voltage of the forward control unit 525 , the phase ⁇ syn of the voltage of the phase control unit 526 , the actual amplitude value, the external input amplitude rated value Vref, the external input reactive power rated value Qref and other parameters, the amplitude control unit 527 may control the voltage amplitude Ve and output the voltage amplitude Ve to the modulation unit 528 .
  • the modulation unit 528 receives the angular velocity ⁇ syn of the voltage, the phase ⁇ syn of the voltage and the amplitude Ve of the voltage, and generates a trigger signal according to the angular velocity ⁇ syn of the voltage, the phase ⁇ syn of the voltage and the amplitude Ve of the voltage.
  • the power electronic devices inside the conversion circuit 510 can be controlled to work, so as to adjust the frequency of the output voltage at the output end of the conversion circuit 510, the phase of the output voltage and the amplitude of the output voltage.
  • the controller 520 after receiving the output voltage signal U1 and the output current signal I1 of the conversion circuit 510, the controller 520 inputs the output voltage signal U1 and the output current signal I1 into the preprocessing unit 521, so that the preprocessing unit 521 calculates the active power Pe and the reactive power Qe.
  • the inertia control unit 522 transforms the amplitude and phase of the active power Pe to obtain the active power Peic after the delayed phase, so as to provide the frequency and phase support characteristics for the new energy converter 500 in the closed-loop control of the active power and the frequency.
  • the active power Pe calculated by the preprocessing unit 521 is 0.
  • the control system does not need to provide frequency and phase support characteristics for the power system.
  • the controller 520 implements the function of frequency and phase support response.
  • the inertia control unit 522 makes the phase of the active power Pe hysteresis and the amplitude of the active power Pe change, so that in the closed-loop control of the active power and frequency, the frequency and phase support characteristics are provided for the new energy converter 500.
  • the controller 520 also receives a power instruction. After receiving the power instruction, the instruction adjustment unit 523 converts the active power Pref corresponding to the power instruction into The power difference ⁇ P inputted by the subtractor 524 to the forward control unit 525 is the difference between the given power Prefa and the active power Peic after phase adjustment.
  • the forward control unit 525 quickly converts the power difference ⁇ P into the voltage ⁇ .
  • the phase control unit 526 integrates the voltage angular velocity ⁇ upon receiving the voltage angular velocity ⁇ to obtain the voltage phase ⁇ .
  • the amplitude control unit 527 can control the voltage amplitude Ve after receiving the reactive power Qe, the input voltage signal U 2 , the output voltage signal U 1 , the voltage angular velocity ⁇ , the voltage phase ⁇ , the amplitude actual value, the external input amplitude rated value Vref, the external input reactive power rated value Qref and other parameters.
  • the modulation unit 528 generates a trigger signal based on the received voltage angular velocity ⁇ , the voltage phase ⁇ and the voltage amplitude Ve.
  • the conversion circuit 510 can control the operation of the power electronic devices inside the conversion circuit 510, so that the power electronic devices inside the conversion circuit 510 can adjust the frequency, phase and amplitude of the output voltage at the output end of the conversion circuit 510.
  • the controller 520 executes the power command response.
  • the command adjustment unit 523 and the forward control unit 525 can quickly adjust the synchronous angular velocity of the voltage, so that the controller 520 can quickly adjust the trigger information.
  • the conversion circuit 510 can quickly adjust the voltage parameters of the output voltage at the output end of the conversion circuit 510, thereby improving the speed of the command response of the conversion circuit 510.
  • the controller 520 does not receive a power command, or the active power Pref corresponding to the power command is 0.
  • the voltage of the power system is unstable, and the active power Pe calculated by the preprocessing unit 521 is ⁇ 0.
  • the power difference ⁇ P -Peic input to the forward control unit 525 by the subtractor 524.
  • the controller 520 provides frequency and phase support characteristics for the power system, and adjusts the voltage parameters of the output voltage at the output end of the conversion circuit 510, so that the voltage parameters of the output voltage at the output end of the conversion circuit 510 follow the voltage parameter changes of the power system.
  • the controller 520 does not receive a power command, or the active power Pref corresponding to the power command is 0.
  • the voltage of the power system is stable, and the active power Pe calculated by the preprocessing unit 521 is 0.
  • the power difference ⁇ P input to the forward control unit 525 by the subtractor 524 is 0.
  • the controller 520 adjusts the voltage parameter of the output voltage at the output end of the conversion circuit 510 to a stable state.
  • the controller 520 receives a power instruction, and the active power Pref corresponding to the power instruction is ⁇ 0.
  • the power difference ⁇ P Prefa-Peic input to the forward control unit 525 by the subtractor 524.
  • the controller 520 provides frequency and phase support characteristics for the power system according to the active power of the preprocessing unit 521.
  • the controller 520 quickly adjusts the voltage parameters of the output voltage of the output end of the conversion circuit 510 according to the active power corresponding to the power instruction and the active power of the preprocessing unit 521, so that the voltage parameters of the output voltage of the output end of the conversion circuit 510 follow the voltage parameter changes of the power system.
  • the command adjustment unit 523 and the forward control unit 525 act on a short time scale, which can speed up the command response speed.
  • the inertia control unit 522 acts on a long time scale, which can provide frequency and phase support characteristics.
  • FIG6 is a flow chart of a control method provided in an embodiment of the present application. As shown in FIG6 , the control method is executed by the controller 520, and the specific process is as follows:
  • step S601 the controller 520 receives an output voltage signal and an output current signal of the conversion circuit 510 .
  • one end of the conversion circuit 510 is electrically connected to the external power supply system, and the other end of the conversion circuit 510 is electrically connected to the power system.
  • the conversion circuit 510 converts AC power into DC power, or converts DC power into AC power.
  • the sampling module inside the conversion circuit 510 samples the output voltage and output current of the output end to obtain the output voltage and output current.
  • the sampling module samples the input voltage and input current of the input end to obtain the input voltage and input current.
  • the sampling module converts the output voltage, the output current, the input voltage and the input current into digital signals to obtain the output voltage signal U 1 , the output current signal I 1 , the input voltage signal U 2 and the input current signal I 2 , and inputs the output voltage signal U 1 , the output current signal I 1 , the input voltage signal U 2 and the input current signal I 2 into the controller 520 .
  • step S602 the controller 520 calculates active power and reactive power according to the output voltage signal and the output current signal.
  • the controller 520 calculates the active power Pe and the reactive power Qe according to the output voltage signal U1 and the output current signal I1 .
  • the controller 520 includes a preprocessing unit 521.
  • the preprocessing unit 521 is used to receive the output voltage signal U 1 , the output current signal I 1 , the input voltage signal U 2 and the input current signal I 2 of the conversion circuit 510.
  • the preprocessing unit 521 is also used to calculate the active power Pe and the reactive power Qe according to the output voltage signal U 1 and the output current signal I 1 , and input the active power Pe to the inertia control unit 522, and input the reactive power Qe, the input voltage signal U 2 , and the output voltage signal U 1 to the amplitude control unit 527.
  • Step S603 the controller 520 delays the phase of the active power to obtain the active power after the phase delay.
  • the controller 520 transforms the amplitude and phase of the active power Pe to obtain the active power Peic after the phase is delayed.
  • the controller 520 processes the amplitude and phase of the active power Pe to delay the phase of the active power Pe and change the amplitude of the active power Pe.
  • the controller 520 includes an inertia control unit 522.
  • the inertia control unit 522 can transform the amplitude and phase of the active power Pe to obtain the active power Peic after the delayed phase.
  • the inertia control unit 522 provides frequency and phase support characteristics for the new energy converter 500.
  • step S604 the controller 520 calculates a power difference between the active power after phase delay and the given power.
  • the controller 520 when the controller 520 receives a power instruction, the controller 520 can perform a difference process between the active power corresponding to the power instruction and the active power after the delayed phase to calculate the power difference. When the controller 520 does not receive a power instruction, the controller 520 can use the active power after the delayed phase as the power difference.
  • the controller 520 includes a command adjustment unit 523.
  • the command adjustment unit 523 is used to process the active power Pref corresponding to the input power command, and convert the active power Pref corresponding to the power command into a given power Prefa.
  • the control system is in a stable state.
  • the given power Prefa output by the command adjustment unit 523 is the same as the active power Peic after the delayed phase output by the inertia control unit 522.
  • the controller 520 does not receive a power command, or the active power Pref corresponding to the power command is 0.
  • the voltage of the power system is unstable, and the active power Pe calculated by the preprocessing unit 521 is 0.
  • the power difference ⁇ P input to the forward control unit 525 by the subtractor 524 is -Peic.
  • the controller 520 does not receive a power command, or the active power Pref corresponding to the power command is 0.
  • the voltage of the power system is stable, and the active power Pe calculated by the preprocessing unit 521 is 0.
  • the power difference ⁇ P input to the forward control unit 525 by the subtractor 524 is 0.
  • the controller 520 receives a power instruction, and the active power Pref corresponding to the power instruction is ⁇ 0.
  • step S605 the controller 520 utilizes the relationship between the power and the frequency of the synchronous motor to convert the voltage frequency according to the power difference.
  • the controller 520 can determine the relationship between power and frequency by analogy with the nonlinear positive relationship between power and frequency of the synchronous motor. After receiving the power difference ⁇ P, the forward control unit 525 converts the power difference ⁇ P into a voltage frequency by using the relationship between power and frequency.
  • the controller 520 includes a forward control unit 525.
  • the forward control unit 525 uses the relationship between the power and frequency of the synchronous motor to quickly convert the power difference ⁇ P into the angular velocity ⁇ syn of the voltage, and outputs the angular velocity ⁇ syn of the voltage to the phase control unit 526, the amplitude control unit 527 and the modulation unit 528.
  • step S606 the controller 520 integrates the angular velocity of the voltage to obtain the phase of the voltage.
  • the controller 520 includes a phase control unit 526.
  • the phase control unit 526 Upon receiving the angular velocity ⁇ syn of the voltage, the phase control unit 526 integrates the angular velocity ⁇ syn of the voltage to obtain the phase ⁇ syn of the voltage, and outputs the phase ⁇ syn of the voltage to the amplitude control unit 527 and the modulation unit 528.
  • step S607 the controller 520 controls the voltage amplitude according to the reactive power rated value, the reactive power actual value, the voltage angular velocity, the voltage phase, the amplitude rated value, and the amplitude actual value.
  • the controller 520 includes an amplitude control unit 527.
  • the amplitude control unit 527 can control the voltage amplitude Ve and output the voltage amplitude Ve to the modulation unit 528.
  • step S608 the controller 520 generates a trigger signal according to the angular velocity of the voltage, the phase of the voltage and the amplitude of the voltage, wherein the trigger signal enables the conversion circuit 510 to adjust the voltage parameters of the output voltage at the output end.
  • the controller 520 includes a modulation unit 528.
  • the modulation unit 528 receives the angular velocity ⁇ syn of the voltage, the phase ⁇ syn of the voltage, and the amplitude Ve of the voltage, and generates a trigger signal according to the angular velocity ⁇ syn of the voltage, the phase ⁇ syn of the voltage, and the amplitude Ve of the voltage.
  • the power electronic devices inside the conversion circuit 510 can be controlled to work, so as to adjust the frequency of the output voltage at the output end of the conversion circuit 510, the phase of the output voltage, and the amplitude of the output voltage.
  • the controller after obtaining the active power at the output end of the conversion circuit, transforms the amplitude and phase of the active power to obtain the active power after the delayed phase, which can provide frequency and phase support characteristics in the active power and frequency closed-loop control.
  • the controller controls the voltage parameters of the output end of the conversion circuit according to the active power after the delayed phase to adjust the voltage parameters of the output end of the conversion circuit.
  • the controller After receiving the power instruction, performs a difference processing on the active power corresponding to the power instruction and the active power after the delayed phase to obtain the power difference.
  • the controller can directly control the voltage parameters of the output end of the conversion circuit according to the power difference, thereby improving the speed of the conversion circuit's instruction response.
  • the present application also provides a grid-connected power system, which includes a first power system, a second power system and One less new energy converter.
  • the first power system may be a backup power supply, a photovoltaic power generation system, a hydropower generation system, a wind power generation system or other power supply system.
  • the second power system may be a power grid system, a household power grid, an enterprise power grid or other power system.
  • the new energy converter may execute the technical solutions shown in FIG. 5-FIG. 6 and the above corresponding technical solutions, so that the grid-connected power system has the technical effect of the above protection technical solution.
  • the embodiment of the present application also provides a computer program product including instructions.
  • the computer program product may be software or a program product including instructions that can be run on a computing device or stored in any available medium.
  • the at least one computing device executes the control method.
  • the embodiment of the present application also provides a computer-readable storage medium.
  • the computer-readable storage medium can be any available medium that can be stored by the computing device or a data storage device such as a data center containing one or more available media.
  • the available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk).
  • the computer-readable storage medium includes instructions that instruct the computing device to execute the control method.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Inverter Devices (AREA)

Abstract

一种新能源变换器的构网控制方法，应用在新能源变换器，新能源变换器包括变换电路和控制器，变换电路的输入端用于连接直流源，输出端用于连接交流系统。控制器在得到变换电路的输出端的有功功率后，对有功功率的相位进行变换，可以在有功功率与频率闭环控制中提供惯量支撑特征。控制器根据延迟相位后的有功功率，快速地控制变换电路的输出端的电压参数，在不影响逆变器的惯量支撑特征下，可以快速地调整变换电路的输出端的电压。

Description

一种控制方法、新能源变换器和并网电力系统
本申请要求于2022年11月02日提交中国国家知识产权局、申请号为202211363404.8、申请名称为“一种控制方法、新能源变换器和并网电力系统”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明涉及电力电子技术领域，尤其涉及一种控制方法、新能源变换器和并网电力系统。
背景技术
近些年来，全球的温度不断地上升，使得碳达峰、碳中和已经成为全球重要国家应对气候变化的核心任务。为了降低碳排放，清洁能源成为未来的发展趋势。清洁能源有太阳能、风能、水能、潮汐能等。通常情况下，清洁能源是无法直接利用的，可以通过转换成电能供给人类使用。例如，光伏发电系统是将太阳能转换成电能，水力发电系统是将水能转换成电能，风力发电系统是将风能转换成电能，以及其他转换方式。
现有技术中，光伏发电系统、水力发电系统等其它发电系统都具有间歇性、波动性、随机性等限制因素，导致无法全天候稳定电力系统。随着新能源装机容量的大规模增加，电力电子装备也随之渗透于电力系统的发、输、配、用、储各个环节，造成电网系统的低惯量、低短路比等特征，降低了电网系统的稳定性。
发明内容
为了解决上述的问题，本申请的实施例中提供了一种控制方法、新能源变换器和并网电力系统，新能源变换器通过指令调整、惯量控制、前向控制等单元，实时调整输出端的有功功率，实现对频率的有功功率支撑、对相位的有功功率支撑。。具体地，控制器在得到变换电路的输出端的有功功率后，对有功功率的相位进行调整，并配合前向控制等单元，可以在有功功率与频率闭环控制中提供频率、相位支撑特征；控制器根据相位调整后的有功功率，通过控制环路调节，实现对电力电子变换器输出端电压参数的调整；另外地，当控制器接收到功率指令后，将功率指令进行指令调整，对应的有功功率调整值与相位调整后的有功功率作差处理，得到功率差值。控制器可以直接根据功率差值，快速地控制变换电路的输出端的电压参数，提高变换电路的指令响应的速度。
为此，本申请的实施例中采用如下技术方案：
第一方面，本申请实施例提供一种新能源变换器的构网控制方法，应用在新能源变换器包括变换电路和控制器，变换电路的输入端用于连接直流源，输出端用于连接交流系统，方法包括：控制器用于控制变换电路输出有功功率，并在交流系统的电压频率出现波动时，延迟有功功率的相位；根据延迟相位后的有功功率，控制变换电路的输出端的电压参数，以使变换电路输出具有惯量支撑的有功功率。其中，发电机组的出力和电力系统的负荷每时每刻都在变化，导致发电机组转动时很难以恒定的速度转动。当电力系统出现发电机组的有功功率和负荷的有功功率不平衡的情况时，电力系统的频率会因为发电机组和负荷的功率不平衡而出现波动，从而使得频率出现波动。
在该实施方式中，控制器在得到变换电路的输出端的有功功率反馈值后，对有功功率反馈值的相位进行调整，可以在有功功率与频率、相位的闭环控制中提供惯量支撑特征。控制器根据相位调整后的有功功率，快速地控制变换电路的输出端的电压参数；特别地，在不影响逆变器的惯量支撑特征下，可以快速地调整变换电路的输出端的电压参数。
在一种实施方式中，在根据延迟相位后的有功功率，控制变换电路的输出端的电压参数之前，还包括：接收功率指令，功率指令用于控制变换电路的输出端的电压参数；根据延迟相位后的有功功率，控制变换电路的输出端的电压参数，包括：将功率指令对应的有功功率与延迟相位后的有功功率作差处理，得到功率差值；根据功率差值，控制变换电路的输出端的电压参数。
在该实施方式中，控制器在接收到功率指令后，控制器根据功率指令对应的有功功率与相位调整后的有功功率作差，得到功率差值，然后快速地控制变换电路的输出端的电压参数，在不影响逆变器的惯量支撑特征下，可以快速地调整变换电路的输出端的电压，提高控制器的指令响应的速度。
在一种实施方式中，在接收功率指令之后，还包括：将功率指令对应的有功功率转换成给定功率；变换电路的输出端的输出电压稳定时，给定功率的数值等于延迟相位后的有功功率；将功率指令对应的有功功率与延迟相位后的有功功率作差处理，得到功率差值，包括：将给定功率与延迟相位后的有功功率作差处理，得到功率差值。
在该实施方式中，控制器在接收到功率指令后，对功率指令对应的有功功率转换成给定功率，让设定功率的数值与变换电路的输出端的输出电压稳定时的相位调整后的有功功率相同。此时，功率差值为零，实现变换电路的输出端的输出电压稳定时，控制器在可以不用调整变换电路的输出端的输出电压。
在一种实施方式中，电压参数包括电压的频率，根据功率差值，控制变换电路的输出端的电压参数，包括：利用同步电机的功率与频率之间的关系，将功率差值转换出电压的频率。
在该实施方式中，控制器根据功率差值转换出电压的频率，实现对变换电路的输出端的输出电压的频率进行调整。
在一种实施方式中，电压参数还包括电压的相位，根据功率差值，控制变换电路的输出端的电压参数，包括：对电压的角速度进行积分，得到电压的相位；电压的频率根据功率差值确定，电压的角速度根据电压的频率确定。
在该实施方式中，控制器对电压的角速度进行积分，得到电压的相位，实现对变换电路的输出端的输出电压的相位进行调整。
在一种实施方式中，电压参数还包括电压的幅值，根据功率差值，控制变换电路的输出端的电压参数，包括：根据无功功率额定值、无功功率实际值、电压的角速度、电压的相位、幅值额定值和幅值实际值，控制电压的幅值以及相位；无功功率根据所述输出电压信号和输出电流信号确定，电压的频率根据功率差值确定，电压的角速度根据电压的频率确定，电压的相位根据电压的角速度确定。
在该实施方式中，控制器根据无功功率、电压的角速度、电压的相位、幅值额定值和无功功率额定值，控制电压的幅值，实现对变换电路的输出端的输出电压的相位进行调整。
在一种实施方式中，方法还包括：根据电压参数，生成触发信号，触发信号用于触发变换电路内部的电力电子器件开通与关断，进一步调整变换电路的输出端的电压参数。
第二方面，本申请实施例提供一种新能源变换器，包括变换电路和控制器，控制器，用于控制变换电路输出有功功率，并在交流系统的电压频率出现波动时，延迟有功功率的相位；根据延迟相位后的有功功率，控制变换电路的输出端的电压参数，以使变换电路输出具有频率、相位支撑作用的有功功率。
在一种实施方式中，控制器，还用于接收功率指令，功率指令用于控制变换电路的输出端的电压参数；将功率指令对应的有功功率与相位调整后的有功功率作差处理，得到功率差值；根据功率差值，控制变换电路的输出端的电压参数。新能源变换器是指常用的电力电子变换器，例如逆变器、整流器、模块化多电平变换器或其它变换器，或者是双向变换器。
在一种实施方式中，控制器，还用于将功率指令对应的有功功率转换成给定功率；变换电路的输出端的输出电压稳定时，给定功率的数值等于延迟相位后的有功功率；将给定功率与延迟相位后的有功功率作差处理，得到功率差值。
在一种实施方式中，电压参数包括电压的频率，控制器，具体用于利用同步电机的功率与频率之间的关系，将功率差值转换出电压的频率。
在一种实施方式中，电压参数还包括电压的相位，控制器，具体用于对电压的角速度进行积分，得到电压的相位；电压的频率根据功率差值确定，电压的角速度根据电压的频率确定。
在一种实施方式中，根据无功功率额定值、无功功率实际值、电压的角速度、电压的相位、幅值额定值和幅值实际值，控制电压的幅值；无功功率根据输出电压信号和输出电流信号确定，电压的频率根据所述功率差值确定，电压的角速度根据电压的频率确定，电压的相位根据电压的角速度确定。
在一种实施方式中，控制器，还用于根据电压参数，生成触发信号，触发信号用于触发变换电路的内部的电力电子器件调整变换电路的输出端的电压参数。
第三方面，本申请实施例提供一种并网电力系统，包括：新能源组件，至少一个第二方面可能实现的新能源变换器，新能源变换器的输入端与新能源组件连接、或通过直流变换器间接与新能源组件连接、或与其他储能等装置连接，新能源变换器的输出端用于与电网或负荷连接，变换器用于将新能源组件的直流电、或直流变换器输出的直流电转化为电网的交流电，或者，将电网的交流电转化为直流电。
第四方面，本申请实施例提供一种计算机可读存储介质，其上存储有计算机程序，当计算机程序在计算机中执行时，令计算机执行第一方面各个可能实现的实施例。
第五方面，本申请实施例提供一种计算机程序产品，其特征在于，计算机程序产品存储有指令，指令在由计算机执行时，使得计算机实施第一方面各个可能实现的实施例。
附图说明
下面对实施例或现有技术描述中所需使用的附图作简单地介绍。
图1为现有技术中一种并网电力系统的架构示意图；
图2(a)为现有技术中构网型控制单元执行指令响应的过程示意图；
图2(b)为现有技术中构网型控制单元执行频率、相位支撑响应的过程示意图；
图3为现有技术中一种构网型控制单元的架构示意图；
图4为现有技术中一种构网型控制单元的架构示意图；
图5为本申请实施例中提供的控制器的架构示意图；
图6为本申请实施例中提供的一种控制方法的流程示意图。
具体实施方式
下面将结合本申请实施例中的附图，对本申请实施例中的技术方案进行描述。
本文中术语“和/或”，是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。本文中符号“/”表示关联对象是或者的关系，例如A/B表示A或者B。
本文中的说明书和权利要求书中的术语“第一”和“第二”等是用于区别不同的对象，而不是用于描述对象的特定顺序。例如，第一响应消息和第二响应消息等是用于区别不同的响应消息，而不是用于描述响应消息的特定顺序。
在本申请实施例中，“示例性的”或者“例如”等词用于表示作例子、例证或说明。本申请实施例中被描述为“示例性的”或者“例如”的任何实施例或设计方案不应被解释为比其它实施例或设计方案更优选或更具优势。确切而言，使用“示例性的”或者“例如”等词旨在以具体方式呈现相关概念。
在本申请实施例的描述中，除非另有说明，“多个”的含义是指两个或者两个以上，例如，多个处理单元是指两个或者两个以上的处理单元等；多个元件是指两个或者两个以上的元件等。
光伏发电系统、水力发电系统、风力发电系统、备用电源等外接电源系统并入电网系统时，一般需要利用逆变器串联在电网系统中。逆变器可以对外接电源系统的电压的频率、电压的相位和电压的幅值等电压参数进行调整，让外接电源系统的电压参数与国家供电系统的电压参数相同。
现有的逆变器根据不同的控制逻辑，可以划分为跟网型控制(grid-following control)逆变器、构网型控制(grid-forming control)逆变器以及其它类型的逆变器。其中，跟网型控制逆变器利用锁相环，让外接电源系统的电压参数与国家供电系统的电压参数相同。构网型控制逆变器利用功率控制的方式，让外接电源系统的电压参数与国家供电系统的电电压参数相同。
跟网型控制逆变器将外接电源系统并入国家电力系统时，跟网型控制逆变器会呈现出低惯量或无惯量的特征。如果大规模的外接电源系统并入电网系统时，会降低电网系统的惯量、系统强度等特征。然而构网型控制逆变器并不会降低电网系统的惯量、系统强度等特征。因此，构网型控制逆变器相比较跟网型控制逆变器更具有优势。
图1为现有技术中一种并网电力系统的架构示意图。如图1所示，并网电力系统100包括电力系统110、逆变器120和外接电源系统130。其中，外接电源系统130通过逆变器120并入到电力系统110中。在其它实施例中，并网电力系统100可以包括有其它元器件，如变压器、电感、电力连接线等，本申请在此不作限定。
逆变器120包括双向直流/交流(direct current/alternating current，DC/AC)变换电路121和构网型控制单元122。双向DC/AC变换电路121的输入端与外接电源系统130电连接。双向DC/AC变换电路121的输出端与电力系统110电连接。双向DC/AC变换电路121将外接电源系统130的直流电转换成交流电，输入到电力系统110中。
构网型控制单元122与双向DC/AC变换电路121耦合，用于接收双向DC/AC变换电路121的输出端的输出电压信号和输出电流信号，以及输入端的输入电压信号和输入电流信号。其中，输出电压信号可以是双向DC/AC变换电路121的直流电压。输出电压信号可以是双向DC/AC变换电路121的交流电压。
构网型控制单元122接收到双向DC/AC变换电路121的输出电压信号和输出电流信号后，对双向DC/AC变换电路121的输出端的电压参数进行调整，让双向DC/AC变换电路121的输出端的电压参数与电力系统 110的电压参数相同。其中，电压参数可以是指电压的频率、电压的相位和电压的幅值。
图2(a)为现有技术中构网型控制单元执行指令响应的过程示意图。如图2(a)所示，构网型控制单元122根据执行功能，划分为构网控制同步单元1221、相位控制单元1222、幅值控制单元1223和预处理单元1224。
预处理单元1224接收到双向DC/AC变换电路121的输出端的输出电压信号和输出电流信号，计算出有功功率Pe。构网控制同步单元1221可以接收外部发送的功率指令对应的有功功率Pref和预处理单元1224的有功功率Pe。构网控制同步单元1221可以类比同步电机的功率与频率之间非线性正向关系，确定出功率与频率之间的关系。构网控制同步单元1221根据接收的有功功率计算出电压的角速度ωsyn。其中，角速度ω与频率f之间关系为ω＝2πf。相位控制单元1222在接收到电压的角速度ωsyn后，对电压的角速度ωsyn积分，得到电压的相位θsyn。幅值控制单元1223接收到电压的角速度ωsyn和电压的相位θsyn等参数，可以计算出电压的幅值Ve，并向双向DC/AC变换电路121发送控制指令，让双向DC/AC变换电路121调整输出端的输出电压的电压参数。
如图2(a)所示，构网型控制单元122执行指令响应时，构网控制同步单元1221接收到外界发送的功率指令。构网型控制单元122接收到功率指令对应的有功功率Pref发生变化时，双向DC/AC变换电路121的输出端的有功功率Pe会随着发生变化。构网控制同步单元1221快速地将的有功功率Pref转换成电压的角速度ωsyn，实现双向DC/AC变换电路121的输出功率可以快速地响应功率指令。
如图2(b)所示，构网型控制单元122执行频率、相位支撑响应时，构网控制同步单元1221接收到预处理单元1224的有功功率Pe。构网型控制单元122接收到预处理单元1224的有功功率Pe发生变化时，构网控制同步单元1221缓慢地将的有功功率Pe转换成电压的角速度ωsyn，避免逆变器120快速地调整输出端的输出电压的电压参数，降低电力系统110的频率、相位支撑特征。
构网型控制单元122在执行指令响应和频率、相位支撑响应两种不同控制逻辑时，构网控制同步单元1221的转换速度相反。如果构网控制同步单元1221的转换速度比较快，会弱化逆变器100的频率、相位支撑特性。如果构网控制同步单元1221的转换速度比较慢，降低逆变器120响应功率指令的速度。因此，现有的构网型控制单元122无法解决功率指令响应和频率、相位支撑响应的矛盾问题。
为了解决构网型控制单元122无法解决指令响应和频率、相位支撑响应的矛盾问题，现有技术中提出两种解决方案，分别如下：
如图3所示，构网型控制单元122还可以包括有参数自适应调节单元1225。参数自适应调节单元1225与构网控制同步单元1221耦合。外接电源系统130并入电力系统110时，外接电源系统130的电压参数与电力系统110的电压参数不同，需要控制逆变器100调节外接电源系统130的电压参数。
构网控制同步单元1221接收到外界发送的功率指令后，执行功率指令响应。构网型控制单元122接收到功率指令对应的有功功率Pref时，会将有功功率Pref发送给参数自适应调节单元1225。参数自适应调节单元1225根据有功功率Pref、构网型控制单元122所处的控制环境信息以及其它状态量，生成控制参数。构网控制同步单元1221可以根据控制参数，自主调节有功功率Pref转换成电压的角速度ωsyn的速度，可以提升逆变器100的响应功率指令的速度，以及降低逆变器100的频率、相位支撑特性。
构网型控制单元122执行频率、相位支撑响应时，预处理单元1224向构网型控制单元122发送有功功率Pe。电力系统110的电压参数发生变化时，构网型控制单元122接收到有功功率Pe发生变化。构网型控制单元122会将有功功率Pe发送给参数自适应调节单元1225。参数自适应调节单元1225根据有功功率Pe、构网型控制单元122所处的控制环境信息以及其它状态量，生成控制参数。构网控制同步单元1221可以根据控制参数，反向自主调节有功功率的角速度ω转换成电压的角速度ωsyn的速度，可以提高逆变器100的频率、相位支撑特性，但会降低逆变器100的响应功率指令的速度。
现有技术中，构网型控制单元122是增加基于参数自适应的技术路径，利用参数自适应调节单元1225根据有功功率和环境因素生成的控制参数，实现对构网控制同步单元1221的转换速度进行调节。控制参数是处于动态变化的状态，使得逆变器100的有功功率转换速度、频率、相位支撑特征等特性会随着控制参数的变化而变化，从而减低了逆变器100的稳定性。另外，参数自适应调节单元1225生成的控制参数在一定数值范围内是可以让构网控制同步单元1221自主调节转换速度。但是，在某些工况下，控制参数超出一定数值范围后，构网控制同步单元1221很难实现自主调节转换速度。
如图4所示，构网型控制单元122还可以包括有指令快速补偿单元1226。指令快速补偿单元1226输出端分别与相位控制单元1222和幅值控制单元1223耦合。外接电源系统130并入电力系统110时，外接电源系统130的电压参数与电力系统110的电压参数不同，需要控制逆变器100调节外接电源系统130的电压参数。
逆变器120接收到功率指令后，将功率指令对应的有功功率Pref发送给构网控制同步单元1221和指令快速补偿单元1226。构网控制同步单元1221接收到外界发送的功率指令后，执行功率指令响应。指令快速补偿单元1226根据功率指令对应的指令功率的变化量以及其它变量，生成频率补偿量、相位补偿量等参数。构网控制同步单元1221将有功功率转换成电压的角速度ωsyn的速度后，输入到相位控制单元1222。相位控制单元1222可以根据指令快速补偿单元1226的相位补偿量进行相位补偿、或幅值控制单元1223可以根据指令快速补偿单元1226的频率补偿量进行频率补偿等方式，可以提升逆变器100的响应功率指令的速度。但是，逆变器100的频率、相位支撑特征会被弱化。
为了解决现有的逆变器的缺陷，本申请实施例提供了一种新能源变换器、控制方法和并网电力系统。
图5为本申请实施例提供的一种新能源变换器的结构示意图。如图5所示，新能源变换器500包括变换电路510和控制器520。本申请中，新能源变换器500的一端与外接电源系统电连接，变换器500的另一端与电力系统电连接。
在一个实施例中，新能源变换器500可以是逆变器、整流器、模块化多电平变换器或其它变换器。其它实施例中，新能源变换器500可以为双向变换器。
在一个实施例中，外接电源系统可以为备用电源、光伏发电系统、水力发电系统、风力发电系统或其它供电系统。
在一个实施例中，电力系统可以为电网系统、家庭电力网、企业电力网或其它电力系统。
变换电路510包括有双向DC/AC变换电路，用于将交流电转换成直流电，或者，将直流电转换成交流电。在一个实施例中，外接电源系统的电压为直流电，电力系统的电压为交流电，变换电路510将外接电源系统的直流电转换成设定电压值的交流电。在其它实施例中，变换电路510可以为其它类型的变换电路，本申请在此不作限定。
控制器520可以为数字信号处理(digital signal processing，DSP)单元、现场可编程逻辑门阵列(field programmable gate array，FPGA)、微控制单元(microcontroller unit，MCU)或其它具有计算与控制功能的器件。本申请中，控制器520在接收到变换电路510的输出端的输出电压信号U1和输出电流信号I1，以及输入端的输入电压信号U2和输入电流信号I2后，调整变换电路510输出端的输出电压的电压参数。控制器520在接收到外接输入的功率指令后，根据功率指令对应的有功功率、变换电路510的输出端的输出电压信号U1和输出电流信号I1，以及输入端的输入电压信号U2和输入电流信号I2，调整变换电路510输出端的输出电压的电压参数。其中，电压参数可以是指电压的频率fsyn、电压的相位θsyn和电压的幅值Ve。
本申请实施例中，控制器520可以根据执行的功能，划分为预处理单元521、惯量控制单元522、指令调整单元523、减法器524、前向控制单元525、相位控制单元526、幅值控制单元527和调制单元528。其中，预处理单元521、惯量控制单元522、指令调整单元523、减法器524、前向控制单元525、相位控制单元526、幅值控制单元527和调制单元528均可以通过软件实现，或者可以通过硬件实现，或者可以通过软件和硬件结合实现。
预处理单元521用于接收变换电路510的输出端的输出电压信号U1和输出电流信号I1。预处理单元521还用于根据输出电压信号U1和输出电流信号I1计算出有功功率Pe和无功功率Qe，并将有功功率Pe输入到惯量控制单元522，以及将无功功率Qe、输入电压信号U2和输出电压信号U1输入到幅值控制单元527。其中，有功功率Pe和无功功率Qe既可以是平均功率，也可以是瞬时功率。针对平均功率，有功功率Pe是指单位时间内实际发出或消耗的交流电能量，是周期内的平均功率；无功功率Qe是指在具有电抗的交流电路中，电场或磁场在一周期的一部分时间内从电源吸收能量，另一部分时间则释放能量，在整个周期内平均功率是零，但能量在电源和电抗元件(电容、电感)之间不停地交换。交换率的最大值即为无功功率Qe。针对瞬时功率，其大小等于瞬时电压与电流的瞬时值的乘积。交流电的瞬时功率不是一个恒定值，瞬时功率在一个周期内的平均值叫做有功功率，因此，有功功率也称平均功率。
本申请实施例中，变换电路510还包括有采样模块。采样模块对输出端的输出电压和输出电流进行采样，得到输出电压和输出电流。采样模块将输出电压和输出电流转换成数字信号，得到输出电压信号U1和输出电流信号I1，并将输出电压信号U1和输出电流信号I1输入到控制器520中。采样模块对输入端的输入电压和输入电流进行采样，得到输入电压和输入电流。采样模块将输入电压和输入电流转换成数字信号，得到输入电压信号U2和输入电流信号I2，并将输入电压信号U2和输入电流信号I2输入到控制器520中。
变换电路510可以为双向变换电路。在一个实施例中，变换电路510的输入端为外接电源系统，变换电路510的输出端为电力系统。输出电压为交流电压，输出电流为交流电流，输入电压为直流电压，输入电流 为直流电流。在一个实施例中，变换电路510的输入端为电力系统，变换电路510的输出端为外接电源系统。输出电压为直流电压，输出电流为直流电流，输入电压为交流电压，输入电流为交流电流。
惯量控制单元522可以是由比例函数、积分方程、一阶低通滤波器、多阶低通滤波器等函数中的一种或多种函数的组合。电力系统的电压频率或电压相位出现波动时，电力系统会引起变换电路510的输出端的输出功率会发生波动。惯量控制单元522可以对有功功率Pe的相位进行变换，得到延迟相位后的有功功率Peic。同时，惯量控制单元522对有功功率Pe的相位进行变换时，有功功率Pe的幅值变化。本申请中，惯量控制单元522对有功功率Pe的幅值和相位进行变换，让有功功率Pe的相位迟滞，让有功功率Pe的幅值变化。惯量控制单元522在有功功率与频率闭环控制中，为新能源变换器500提供频率、相位支撑特征。
在一个实施例中，惯量控制单元522的惯量控制可以等效于摇摆方程的一阶低通滤波器。有功功率Pe输入到一阶低通滤波器后，一阶低通滤波器可以根据稳定参数1/KD转换对有功功率Pe的幅值和相位进行转换，让有功功率Pe的相位迟滞，让有功功率Pe的幅值变化。
指令调整单元523可以是由比例函数、积分方程、转子运动方程、一阶低通滤波器、多阶低通滤波器等函数中的一种或多种函数的组合。指令调整单元523用于对输入的功率指令对应的有功功率Pref进行处理，将功率指令对应的有功功率Pref转换成给定功率Prefa。变换电路510的输出端的输出电压稳定时，也即控制系统处于稳定状态。指令调整单元523输出的给定功率Prefa与惯量控制单元522输出的延迟相位后的有功功率Peic相同。
在一个实施例中，指令调整单元523为比例函数，指令调整单元523将功率指令对应的有功功率Pref除以设定比例值，得到给定功率Prefa。
在一个实施例中，指令调整单元523为一阶低通滤波器，指令调整单元523对功率指令对应的有功功率Pref进行滤波处理，将功率指令对应的有功功率Pref转换成给定功率Prefa。
减法器524用于接收指令调整单元523输出的给定功率Prefa和惯量控制单元输出的延迟相位后的有功功率Peic，并对给定功率Prefa和延迟相位后的有功功率Peic作差处理，得到功率差值△P。
前向控制单元525可以是由比例函数、微分方程、低通滤波器、高通滤波器、超前/滞后校正函数等函数中的一种或多种函数的组合。前向控制单元525可以类比同步电机的功率与频率之间非线性正向关系，确定出功率与频率之间的关系。前向控制单元525在接收到功率差值△P后，利用功率与频率之间的关系，快速地将功率差值△P转换成电压的角速度ωsyn，并将电压的角速度ωsyn输出到相位控制单元526、幅值控制单元527和调制单元528。
在一个实施例中，前向控制单元525为比例函数、微分方程和低通滤波器的组合，前向控制单元525对功率差值△P除以设定比例值、微分和滤波处理，得到功率差值△P对应的电压的角速度ωsyn。
相位控制单元526可以是积分器或积分器与其它器件的结合。相位控制单元526在接收到电压的角速度ωsyn，对电压的角速度ωsyn进行积分，得到电压的相位θsyn，并将电压的相位θsyn输出到幅值控制单元527和调制单元528。
幅值控制单元527可以是由比例函数、积分方程、比例积分方程等函数中的一种或多种函数的组合。幅值控制单元527接收到预处理单元521的无功功率Qe、输入电压信号U2、输出电压信号U1、前向控制单元525的电压的角速度ωsyn、相位控制单元526的电压的相位θsyn、幅值实际值、外界输入的幅值额定值Vref、外界输入的无功功率额定值Qref等参数后，可以控制电压的幅值Ve，并将电压的幅值Ve输出到调制单元528。
调制单元528在接收到电压的角速度ωsyn、电压的相位θsyn和电压的幅值Ve，并根据电压的角速度ωsyn、电压的相位θsyn和电压的幅值Ve，生成触发信号。角速度ω与频率f之间关系为ω＝2πf，根据电压的角速度ωsyn即可得到电压的频率fsyn。变换电路510接收到触发信号后，可以控制变换电路510内部的电力电子器件工作，实现调整变换电路510的输出端的输出电压的频率、输出电压的相位和输出电压的幅值。
本申请实施例中，控制器520在接收到变换电路510的输出电压信号U1和输出电流信号I1后，将输出电压信号U1和输出电流信号I1输入到预处理单元521中，让预处理单元521计算出有功功率Pe和无功功率Qe。惯量控制单元522对有功功率Pe的幅值和相位进行变换，得到延迟相位后的有功功率Peic，实现在有功功率与频率的闭环控制中，为新能源变换器500提供频率、相位支撑特征。
电力系统的电压参数没有发生变化时，预处理单元521计算出的有功功率Pe＝0。控制系统不需要为电力系统提供频率、相位支撑特征。电力系统的电压参数发生变化时，控制器520实现频率、相位支撑响应的功能。惯量控制单元522让有功功率Pe的相位迟滞，让有功功率Pe的幅值变化，使得在有功功率与频率的闭环控制中，为新能源变换器500提供频率、相位支撑特征。
控制器520还接收功率指令。指令调整单元523接收到功率指令后，将功率指令对应的有功功率Pref转 换成给定功率Prefa。减法器524输入到前向控制单元525的功率差值△P为给定功率Prefa与相位调整后的有功功率Peic之间的差值。
前向控制单元525快速地将功率差值△P转换出电压的ω。相位控制单元526在接收到电压的角速度ω，对电压的角速度ω进行积分，得到电压的相位θ。幅值控制单元527接收到无功功率Qe、输入电压信号U2、输出电压信号U1、电压的角速度ω、电压的相位θ、幅值实际值、外界输入的幅值额定值Vref、外界输入的无功功率额定值Qref等参数后，可以控制电压的幅值Ve。调制单元528根据在接收到电压的角速度ω、电压的相位θ和电压的幅值Ve，生成触发信号。
变换电路510接收到触发信号后，可以控制变换电路510内部的电力电子器件动作，让变换电路510内部的电力电子器件调整变换电路510的输出端的输出电压的频率、输出电压的相位和输出电压的幅值。
该实施例中，控制器520接收到外界发送的功率指令后，执行功率指令响应。指令调整单元523与前向控制单元525可以快速地调整电压的同步角速度，让控制器520可以快速地调整触发信息。变换电路510在接收到触发信息后，可以快速地调整变换电路510输出端的输出电压的电压参数，提高变换电路510的指令响应的速度。
在一个实施例中，控制器520没有接收到功率指令，或者，功率指令对应的有功功率Pref＝0。电力系统的电压不稳定，预处理单元521计算出的有功功率Pe≠0。减法器524输入到前向控制单元525的功率差值△P＝-Peic。此时，控制器520为电力系统提供频率、相位支撑特征，以及调整变换电路510的输出端的输出电压的电压参数，让变换电路510的输出端的输出电压的电压参数跟随电力系统的电压参数变化。
在一个实施例中，控制器520没有接收到功率指令，或者，功率指令对应的有功功率Pref＝0。电力系统的电压稳定，预处理单元521计算出的有功功率Pe＝0。减法器524输入到前向控制单元525的功率差值△P＝0。此时，控制器520调整变换电路510的输出端的输出电压的电压参数趋于稳定状态。
在一个实施例中，控制器520接收到功率指令，功率指令对应的有功功率Pref≠0。减法器524输入到前向控制单元525的功率差值△P＝Prefa-Peic。此时，控制器520根据预处理单元521的有功功率，为电力系统提供频率、相位支撑特征。以及，控制器520根据功率指令对应的有功功率和预处理单元521的有功功率，快速地调整变换电路510的输出端的输出电压的电压参数，让变换电路510的输出端的输出电压的电压参数跟随电力系统的电压参数变化。
本申请实施例中，指令调整单元523与前向控制单元525作用于短时间尺度，可以加快指令响应速度。惯量控制单元522作用于长时间尺度，可以提供频率、相位支撑特征。
图6为本申请实施例中提供的一种控制方法的流程示意图。如图6所示，控制方法是由控制器520执行，具体过程如下：
步骤S601，控制器520接收变换电路510的输出电压信号和输出电流信号。
具体地，变换电路510的一端与外接电源系统电连接，变换电路510的另一端与电力系统电连接。变换电路510将交流电转换成直流电，或者，将直流电转换成交流电。变换电路510内部的采样模块对输出端的输出电压和输出电流进行采样，得到输出电压和输出电流。采样模块对输入端的输入电压和输入电流进行采样，得到输入电压和输入电流。
在一个实施例中，采样模块将输出电压、输出电流、输入电压和输入电流转换成数字信号，得到输出电压信号U1、输出电流信号I1、输入电压信号U2和输入电流信号I2，并将输出电压信号U1、输出电流信号I1、输入电压信号U2和输入电流信号I2输入到控制器520中。
步骤S602，控制器520根据输出电压信号和输出电流信号，计算出有功功率和无功功率。
具体地，控制器520在接收变换电路510的输出电压信号U1和输出电流信号I1后，根据输出电压信号U1和输出电流信号I1计算出有功功率Pe和无功功率Qe。
在一个实施例中，控制器520包括有预处理单元521。预处理单元521用于接收变换电路510的输出电压信号U1、输出电流信号I1、输入电压信号U2和输入电流信号I2。预处理单元521还用于根据输出电压信号U1和输出电流信号I1计算出有功功率Pe和无功功率Qe，并将有功功率Pe输入到惯量控制单元522，以及将无功功率Qe、输入电压信号U2、输出电压信号U1、输入到幅值控制单元527。
步骤S603，控制器520延迟有功功率的相位，得到延迟相位后的有功功率。
具体地，控制器520对有功功率Pe的幅值和相位进行变换，得到延迟相位后的有功功率Peic。控制器520对有功功率Pe的幅值和相位进行处理，让有功功率Pe的相位迟滞，让有功功率Pe的幅值变化。
在一个实施例中，控制器520包括有惯量控制单元522。电力系统的电压频率或电压相位出现波动时， 电力系统会引起变换电路510的输出端的输出功率会发生波动。惯量控制单元522可以对有功功率Pe的幅值和相位进行变换，得到延迟相位后的有功功率Peic。惯量控制单元522在有功功率与频率闭环控制中，为新能源变换器500提供频率、相位支撑特征。
步骤S604，控制器520对延迟相位后的有功功率与给定功率，计算出功率差值。
具体地，控制器520接收到功率指令时，控制器520可以将功率指令对应的有功功率与延迟相位后的有功功率作差处理，计算出功率差值。控制器520没有接收到功率指令时，控制器520可以将延迟相位后的有功功率作为功率差值。
在一个实施例中，控制器520包括有指令调整单元523。指令调整单元523用于对输入的功率指令对应的有功功率Pref进行处理，将功率指令对应的有功功率Pref转换成给定功率Prefa。变换电路510的输出端的输出电压稳定时，也即控制系统处于稳定状态。指令调整单元523输出的给定功率Prefa与惯量控制单元522输出的延迟相位后的有功功率Peic相同。
在一个实施例中，控制器520没有接收到功率指令，或者，功率指令对应的有功功率Pref＝0。电力系统的电压不稳定，预处理单元521计算出的有功功率Pe≠0。减法器524输入到前向控制单元525的功率差值△P＝-Peic。
在一个实施例中，控制器520没有接收到功率指令，或者，功率指令对应的有功功率Pref＝0。电力系统的电压稳定，预处理单元521计算出的有功功率Pe＝0。减法器524输入到前向控制单元525的功率差值△P＝0。
在一个实施例中，控制器520接收到功率指令，功率指令对应的有功功率Pref≠0。减法器524输入到前向控制单元525的功率差值△P＝Prefa-Peic。
步骤S605，控制器520利用同步电机的功率与频率之间的关系，根据功率差值转换出电压的频率。
具体地，控制器520可以类比同步电机的功率与频率之间非线性正向关系，确定出功率与频率之间的关系。前向控制单元525在接收到功率差值△P后，利用功率与频率之间的关系，将功率差值△P转换成电压的频率。
在一个实施例中，控制器520包括有前向控制单元525。前向控制单元525在接收到功率差值△P后，利用同步电机的功率与频率之间的关系，快速地将功率差值△P转换成电压的角速度ωsyn，并将电压的角速度ωsyn输出到相位控制单元526、幅值控制单元527和调制单元528。角速度ω与频率f之间关系为ω＝2πf，根据电压的角速度ωsyn即可得到电压的频率fsyn。
步骤S606，控制器520对电压的角速度积分，得到电压的相位。
在一个实施例中，控制器520包括有相位控制单元526。相位控制单元526在接收到电压的角速度ωsyn，对电压的角速度ωsyn进行积分，得到电压的相位θsyn，并将电压的相位θsyn输出到幅值控制单元527和调制单元528。
步骤S607，控制器520根据无功功率额定值、无功功率实际值、电压的角速度、电压的相位、幅值额定值和幅值实际值，控制电压的幅值。
在一个实施例中，控制器520包括有幅值控制单元527。幅值控制单元527接收到预处理单元521的无功功率Qe、输入电压信号U2、输出电压信号U1、前向控制单元525的电压的角速度ωsyn、相位控制单元526的电压的相位θsyn、幅值实际值、外界输入的幅值额定值Vref、外界输入的无功功率额定值Qref等参数后，可以控制电压的幅值Ve，并将电压的幅值Ve输出到调制单元528。
步骤S608，控制器520根据电压的角速度、电压的相位和电压的幅值，生成触发信号。其中，触发信号让变换电路510调整输出端的输出电压的电压参数。
在一个实施例中，控制器520包括有调制单元528。调制单元528在接收到电压的角速度ωsyn、电压的相位θsyn和电压的幅值Ve，并根据电压的角速度ωsyn、电压的相位θsyn和电压的幅值Ve，生成触发信号。角速度ω与频率f之间关系为ω＝2πf，根据电压的角速度ωsyn即可得到电压的频率fsyn。变换电路510接收到触发信号后，可以控制变换电路510内部的电力电子器件工作，实现调整变换电路510的输出端的输出电压的频率、输出电压的相位和输出电压的幅值。
本申请实施例中，控制器在得到变换电路的输出端的有功功率后，对有功功率的幅值和相位进行变换，得到延迟相位后的有功功率，可以在有功功率与频率闭环控制中提供频率、相位支撑特征。控制器根据延迟相位后的有功功率，控制变换电路的输出端的电压参数，实现调整变换电路的输出端的电压参数。控制器接收到功率指令后，将功率指令对应的有功功率与延迟相位后的有功功率作差处理，得到功率差值。控制器可以直接根据功率差值，快速地控制变换电路的输出端的电压参数，提高变换电路的指令响应的速度。
本申请实施例中还提供了一种并网电力系统，该并网电力系统包括第一电力系统、第二电力系统和至 少一个新能源变换器。其中，第一电力系统可以是备用电源、光伏发电系统、水力发电系统、风力发电系统或其它供电系统。第二电力系统可以是电网系统、家庭电力网、企业电力网或其它电力系统。新能源变换器可以执行如图5-图6和上述对应的技术方案，使得并网电力系统具有上述保护的技术方案的技术效果。
本申请实施例还提供了一种包含指令的计算机程序产品。所述计算机程序产品可以是包含指令的，能够运行在计算设备上或被储存在任何可用介质中的软件或程序产品。当所述计算机程序产品在至少一个计算设备上运行时，使得至少一个计算设备执行控制方法。
本申请实施例还提供了一种计算机可读存储介质。所述计算机可读存储介质可以是计算设备能够存储的任何可用介质或者是包含一个或多个可用介质的数据中心等数据存储设备。所述可用介质可以是磁性介质，(例如，软盘、硬盘、磁带)、光介质(例如，DVD)、或者半导体介质(例如固态硬盘)等。该计算机可读存储介质包括指令，所述指令指示计算设备执行控制方法。
最后应说明的是：以上实施例仅用以说明本发明的技术方案，而非对其限制；尽管参照前述实施例对本发明进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本发明各实施例技术方案的保护范围。

Claims (15)

  1. 一种新能源变换器的构网控制方法，应用在新能源变换器，其特征在于，所述新能源变换器包括变换电路和控制器，所述变换电路的输入端用于连接直流源，输出端用于连接交流系统，所述方法包括：
    所述控制器用于控制所述变换电路输出有功功率，并在所述交流系统的电压频率出现波动时，延迟所述有功功率的相位；
    所述控制器根据延迟相位后的有功功率，控制所述变换电路的输出端的电压参数，以使所述变换电路输出具有惯量支撑的有功功率。
  2. 根据权利要求1所述的方法，其特征在于，在所述控制器根据延迟相位后的有功功率，控制所述变换电路的输出端的电压参数之前，还包括：
    接收功率指令，所述功率指令用于控制所述变换电路的输出端的电压参数；
    所述根据延迟相位后的有功功率，控制所述变换电路的输出端的电压参数，包括：
    将所述功率指令对应的有功功率与所述延迟相位后的有功功率作差处理，得到功率差值；
    根据所述功率差值，控制所述变换电路的输出端的电压参数。
  3. 根据权利要求2所述的方法，其特征在于，在所述接收功率指令之后，还包括：
    将所述功率指令对应的有功功率转换成给定功率；所述变换电路的输出端的输出电压稳定时，所述给定功率的数值等于所述延迟相位后的有功功率；
    所述将所述功率指令对应的有功功率与所述延迟相位后的有功功率作差处理，得到功率差值，包括：
    将所述给定功率与所述延迟相位后的有功功率作差处理，得到功率差值。
  4. 根据权利要求2或3所述的方法，其特征在于，所述电压参数包括电压的频率，
    所述根据所述功率差值，控制所述变换电路的输出端的电压参数，包括：
    利用同步电机的功率与频率之间的关系，将所述功率差值转换出所述电压的频率。
  5. 根据权利要求1-4任意一项所述的方法，其特征在于，所述电压参数还包括电压的相位，
    所述根据所述功率差值，控制所述变换电路的输出端的电压参数，包括：
    对电压的角速度进行积分，得到所述电压的相位；所述电压的频率根据所述功率差值确定，所述电压的角速度根据所述电压的频率确定。
  6. 根据权利要求1-5任意一项所述的方法，其特征在于，所述电压参数还包括电压的幅值，
    所述根据所述功率差值，控制所述变换电路的输出端的电压参数，包括：
    根据无功功率额定值、无功功率、电压的角速度、所述电压的相位、幅值额定值和幅值实际值，控制所述电压的幅值；所述无功功率根据所述输出电压信号和所述输出电流信号确定，所述电压的频率根据所述功率差值确定，所述电压的角速度根据所述电压的频率确定，所述电压的相位根据所述电压的角速度确定。
  7. 根据权利要求1-6任意一项所述的方法，其特征在于，所述方法还包括：
    根据所述电压参数，生成触发信号，所述触发信号用于触发所述变换电路的内部的电力电子器件调整所述变换电路的输出端的电压参数。
  8. 一种新能源变换器，其特征在于，包括变换电路和控制器，
    所述控制器，用于控制所述变换电路输出有功功率，并在所述交流系统的电压频率出现波动时，延迟所述有功功率的相位；
    根据延迟相位后的有功功率，控制所述变换电路的输出端的电压参数，以使所述变换电路输出具有惯量支撑的有功功率。
  9. 根据权利要求8所述的新能源变换器，其特征在于，所述控制器，还用于接收功率指令，所述功率指令用于控制所述变换电路的输出端的电压参数；
    将所述功率指令对应的有功功率与所述延迟相位后的有功功率作差处理，得到功率差值；
    根据所述功率差值，控制所述变换电路的输出端的电压参数。
  10. 根据权利要求9所述的新能源变换器，其特征在于，所述控制器，还用于将所述功率指令对应的有功功率转换成给定功率；所述变换电路的输出端的输出电压稳定时，所述给定功率的数值等于所述延迟相位后的有功功率；
    将所述给定功率与所述延迟相位后的有功功率作差处理，得到功率差值。
  11. 根据权利要求9或10所述的新能源变换器，其特征在于，所述电压参数包括电压的频率，
    所述控制器，具体用于利用同步电机的功率与频率之间的关系，将所述功率差值转换出所述电压的频率。
  12. 根据权利要求8-11任意一项所述的新能源变换器，其特征在于，所述电压参数还包括电压的相位，
    所述控制器，具体用于对电压的角速度进行积分，得到所述电压的相位；所述电压的频率根据所述功率差值确定，所述电压的角速度根据所述电压的频率确定。
  13. 根据权利要求8-12任意一项所述的新能源变换器，其特征在于，所述电压参数还包括电压的幅值，
    所述控制器，具体用于无功功率额定值、无功功率实际值、电压的角速度、电压的相位、幅值额定值和幅值实际值，控制所述电压的幅值；所述无功功率根据所述输出电压信号和所述输出电流信号确定，所述电压的频率根据所述功率差值确定，所述电压的角速度根据所述电压的频率确定，所述电压的相位根据所述电压的角速度确定。
  14. 根据权利要求9-13任意一项所述的新能源变换器，其特征在于，所述控制器，还用于根据所述电压参数，生成触发信号，所述触发信号用于触发所述变换电路的内部的电力电子器件调整所述变换电路的输出端的电压参数。
  15. 一种并网电力系统，其特征在于，包括：
    新能源组件，
    至少一个如权利要求8-14任意一项所述的新能源变换器，所述新能源变换器的输入端与新能源组件连接，所述新能源变换器的输出端用于与电网连接，所述变换器用于将所述新能源组件的直流电转化为所述电网的交流电，或者，将所述电网的交流电转化为所述新能源组件的直流电。
PCT/CN2023/105525 2022-11-02 2023-07-03 一种控制方法、新能源变换器和并网电力系统 WO2024093334A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202211363404.8 2022-11-02
CN202211363404.8A CN115764987A (zh) 2022-11-02 2022-11-02 一种控制方法、新能源变换器和并网电力系统

Publications (1)

Publication Number Publication Date
WO2024093334A1 true WO2024093334A1 (zh) 2024-05-10

Family

ID=85355503

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2023/105525 WO2024093334A1 (zh) 2022-11-02 2023-07-03 一种控制方法、新能源变换器和并网电力系统

Country Status (2)

Country Link
CN (1) CN115764987A (zh)
WO (1) WO2024093334A1 (zh)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115764987A (zh) * 2022-11-02 2023-03-07 华为数字能源技术有限公司 一种控制方法、新能源变换器和并网电力系统
CN116388253B (zh) * 2023-06-07 2023-08-18 南方电网科学研究院有限责任公司 一种基于惯量支撑的双向充电模块控制方法和系统

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110797885A (zh) * 2019-11-29 2020-02-14 国网江苏省电力有限公司常州供电分公司 基于虚拟阻抗的三相四桥臂虚拟同步功率解耦控制方法
US20200212823A1 (en) * 2019-01-02 2020-07-02 General Electric Company Virtual synchronous generator system and method with virtual inertia control
CN112003324A (zh) * 2020-08-24 2020-11-27 四川大学 一种基于复合滤波算法的改进微电网控制方法
CN113258603A (zh) * 2021-04-15 2021-08-13 江苏大学 基于孤岛状态下vsg的二阶线性自抗扰控制系统及控制方法
CN115764987A (zh) * 2022-11-02 2023-03-07 华为数字能源技术有限公司 一种控制方法、新能源变换器和并网电力系统

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20200212823A1 (en) * 2019-01-02 2020-07-02 General Electric Company Virtual synchronous generator system and method with virtual inertia control
CN110797885A (zh) * 2019-11-29 2020-02-14 国网江苏省电力有限公司常州供电分公司 基于虚拟阻抗的三相四桥臂虚拟同步功率解耦控制方法
CN112003324A (zh) * 2020-08-24 2020-11-27 四川大学 一种基于复合滤波算法的改进微电网控制方法
CN113258603A (zh) * 2021-04-15 2021-08-13 江苏大学 基于孤岛状态下vsg的二阶线性自抗扰控制系统及控制方法
CN115764987A (zh) * 2022-11-02 2023-03-07 华为数字能源技术有限公司 一种控制方法、新能源变换器和并网电力系统

Also Published As

Publication number Publication date
CN115764987A (zh) 2023-03-07

Similar Documents

Publication Publication Date Title
WO2024093334A1 (zh) 一种控制方法、新能源变换器和并网电力系统
CN110011364B (zh) 一种降低有功功率载荷波动对系统稳定影响的控制方法
CN108429281A (zh) 一种lcl型并网逆变器并联虚拟阻抗控制方法
WO2021110171A1 (zh) 一种基于p-u下垂特性的虚拟直流电机控制方法
Wang et al. Improved linear ADRC for hybrid energy storage microgrid output-side converter
Gonzalez et al. A robust controller for a grid-tied inverter connected through an LCL filter
Zhang et al. Application of repetitive control in electric spring
Xie et al. Frequency coupling admittance modeling of quasi-PR controlled inverter and its stability comparative analysis under the weak grid
CN105656309B (zh) 一种用于风电变流器的硬件滞环电流控制方法
CN110556842B (zh) 一种直驱风电场感性弱电网并网次同步振荡抑制装置的控制方法
Davari et al. Active rectifiers and their control
Narayanan et al. SOGI-FLL-WDCRC Filter for Seamless Control of Microgrid for Optimal Coordination of Conventional and Renewable Energy Resources
Li et al. Hybrid-modulation hysteresis scheme based decoupled power control of grid-connected inverter
CN115566922A (zh) 基于回比矩阵重构的并网逆变器中锁相环参数设计方法
CN113517716B (zh) 一种微电网逆变器的无缝切换控制策略
CN109378847B (zh) 一种微电网储能pcs控制系统和方法
CN113964837A (zh) 适用于lcl型并联有源电力滤波器的复合控制方法和系统
Fang et al. High performance unified control for interlinking converter in hybrid AC/DC microgrid
Lala et al. Improved Power Quality SOGI Based Grid Integrated PV System under Abnormal Conditions by using Interweaved GI
Arulkumar et al. Robust control design of grid power converters in improving power quality
Li et al. A torque control method based on I-MR controller for IPMSM drive with small DC-link capacitor
Yang et al. Current PIλ Control of the Single-Phase Grid Inverter
CN112491075A (zh) 一种新型储能逆变器控制装置及其控制方法
Tu et al. Impedance-phase and magnitude control method to improve the stability of grid-connected inverters in a weak grid
Zhao et al. Improved cascade-type repetitive control of grid-tied inverter with LCL filter