DE102019124268B4 - Process for the external and internal control of a centrifugal massless storage power plant - Google Patents

Abstract

Method for external and internal control of a flywheel-free storage power plant for the provision of system services which include instantaneous reserve, primary control and secondary control, method comprising the following procedural steps: external control, which includes active power control on a DC / AC converter: selecting a control mode, with a The control mode is an angle-based control (φReg mode) and a second control mode is a frequency-based control (fReg mode), the frequency-based control having the following process steps: Measurement of a currently emitted active power (p) at the DC / AC converter and specification of a Change of a power plant target power (ΔpH2) based on the content of a hydrogen storage tank, - Formation of a control deviation (Δp) from the measured currently emitted active power (p) with a target active power, the target active power being a specified secondary power change (Δpsec), a specified timetable an output (pFP) and the specification of the change in the power plant's target output (ΔpH2) and- calculating a synthetic network angular velocity (Δω2) from the control deviation (Δp), with the synthetic angular velocity (Δω2) being an integral adjustment of the voltage angle (φU2) at the DC / AC converter leads, the angle-based control in Slack mode having the following process steps: - Setting a control deviation Δp = 0, whereby the voltage angle (φU2) at the DC / AC converter remains constant and the storage power plant as a voltage source with constant voltage (u2) and a constant frequency of 50 Hz, the angle-based regulation having safety mechanisms which are switched on based on the measured momentarily output power p by means of a control unit, the safety mechanisms comprising the following variants: manual setting of a power (pman), power setting based on a predefined Maximum power value (pMax) and / or a predefined minimum power value (pMin) and / or power setting based on a specification of a change in a power plant target power (ΔpH2) based on the content of a hydrogen storage tank, - internal regulation: provision of system services from storage facilities, which comprises the following process steps: - determining a direct current ( iKC), which flows from a first memory to the DC / AC converter, from a measured memory voltage (uc) of the first memory and the active power (p), the direct current (iKC) and a current flowing from a second memory to the first memory (iCB) integrally sets the storage voltage (uc) of the first storage unit - regulating the direct current (iCB), which flows from the first storage unit to the second storage unit, in such a way that the storage voltage (uc) of the first storage unit has a nominal value of the storage voltage (uc, soll) - Charging the second storage device by means of a direct current (iBF) generated with a first energy converter when falling below a first storage voltage value (ŭB) of the second storage unit, whereby a third storage unit is discharged, or discharging of the second storage unit by means of a current (iEB) generated by a second energy converter when a second storage voltage value (ûB) of the second storage unit is exceeded, whereby a Loading of the third memory takes place.

Description

The invention relates to a method for external and internal regulation of a flywheel-free storage power plant for providing system services which include instantaneous reserve, primary regulation and secondary regulation.

1. 1 Weiträumige und feinverteilte Energieversorgung benötigt ein Drehstromnetz.
2. 2 Plötzliche Laständerungen müssen instantan durch Momentanreserveleistung gespeist werden.
3. 3 Die Speicher der Momentanreserveleistung müssen im Sekundenbereich durch die Primärregelung entlastet und wieder aufgefüllt werden. Dazu werden Primärregelleistungsspeicher benötigt.
4. 4 Die Primärregelleistung muss im Minutenbereich durch die Sekundärrregelung abgelöst werden. Dabei ist dann auch deren Speicher wieder aufzuladen.
5. 5 Anschließend treten Fahrplanänderungen in Kraft, welche alle Regler wieder „auf null“ stellen.
6. 6 In einer vollregenerativ versorgten Energieversorgung kommt. Noch folgende Aufgabe hinzu: Gewisse Mengen der geernteten Energie müssen für Prognosefehler sowie „Dunkelflauten“ gespeichert werden.

The basic principles of electrical energy supply and grid control are universal and must be adhered to for all types of generation, transmission, distribution and consumption as follows:

1. 1 Spacious and finely distributed energy supply requires a three-phase network.
2. 2 Sudden changes in load must be fed instantaneously by instantaneous reserve power.
3. 3 The memory for the instantaneous reserve power must be relieved and refilled within seconds by the primary control. Primary control reserve stores are required for this.
4. 4 The primary control power must be replaced by the secondary control in the minute range. In doing so, their memory must then also be recharged.
5. 5 Changes to the schedule then come into effect, which reset all controllers to "zero".
6. 6 In a fully regenerative energy supply comes. The following additional task: Certain amounts of the harvested energy must be saved for forecast errors and “dark doldrums”.

• Umwandlung/Anpassung: Die sprungförmige elektrische Leistungsanforderung wird vom Generator bei noch konstanter Drehzahl instantan in eine sprungförmige Erhöhung des Luftspalt-Moments und damit der mechanischen Leistung umgesetzt.
• Speicher: Der Turbosatz bestehend aus Turbine-Generator-Erreger speichert instantan kinetische Energie aus und liefert diese mechanische Leistung. Dadurch sinkt die Drehzahl ab, welche die Größe des Speicherinhaltes kennzeichnet.
• Umwandlung/Anpassung: Der Primärregler greift über ein Turbinenventil auf einen Frischdampfspeicher zu, wodurch im Sekundenbereich der Dampfstrom erhöht wird. Damit steigt das Turbinenmoment an und füllt den Drehzahl-Speicher wieder auf.
• Speicher: Durch den erhöhten Dampfstrom sinkt der Dampfdruck ab, welcher hier die Größe des Speicherinhaltes kennzeichnet.
• Umwandlung/Anpassung: Der Brennstoffregler erhöht die Feuerung um den Druck auszuregeln. Dabei wird mehr Kohlenstoff C mit Sauerstoff O zu CO2 umgewandelt. Im Verdampfer wird mehr Dampf erzeugt. Mit dem erhöhten Dampfstrom wird der Druck-Speicher wieder aufgefüllt.
• Speicher: Der Brennstoffregler greift im Minutenbereich auf die Kohlehalde zu und erhöht den Brennstoff-Massenstrom. Die Kohlemasse der Halde wird weniger, welche hier die Größe des Speicherinhalts kennzeichnet. Hier findet keine Wiederaufladung durch das Kraftwerk selbst statt.

So far, these tasks have been performed by conventional power plants, which are built up from a system chain consisting of storage units of different speeds and converters / adapters. This system chain includes (using the example of an abrupt performance requirement):

• Conversion / adaptation: The sudden electrical power demand is instantaneously converted by the generator into a sudden increase in the air gap torque and thus the mechanical power while the speed is still constant.
• Storage: The turbo set consisting of the turbine generator exciter stores kinetic energy instantaneously and delivers this mechanical power. This reduces the speed, which characterizes the size of the memory content.
• Conversion / adaptation: The primary controller accesses a live steam store via a turbine valve, which increases the steam flow in a matter of seconds. This increases the turbine torque and refills the speed memory.
• Storage: Due to the increased steam flow, the steam pressure drops, which here characterizes the size of the storage contents.
• Conversion / adaptation: The fuel regulator increases the firing to regulate the pressure. In the process, more carbon C is converted to CO2 with oxygen O. More steam is generated in the evaporator. The pressure accumulator is refilled with the increased steam flow.
• Storage: The fuel regulator accesses the coal dump within minutes and increases the fuel mass flow. The coal mass of the heap becomes less, which here characterizes the size of the storage content. No recharging takes place here by the power plant itself.

Due to the increasing availability of regenerative energy sources from wind and sun, the conventional power plant has to reduce its output significantly at certain times in order to make room for these producers. To do this, the minimum output must be reduced and the control speed increased. All producers of fossil fuels have to face these requirements today.

In order to be able to continue to implement the above-mentioned supply and network control tasks in a fully regenerative world, new "conventional" power plants have already been developed which not only deliver energy in "dark doldrums", but can also store it in surplus situations. For a transitional period, these new systems also have to function in a flywheel-oriented energy supply with conventional power plants. In a purely converter-oriented energy supply, they can then also be operated either in a grid-forming manner or in a grid-supporting manner at a constant grid frequency.

In the course of the energy transition, more and more electrical energy is being generated by wind and PV systems, for example. This energy is stored in large chemical storage facilities (storage power plants). These new storage power plants are connected to the three-phase network with converters. So far, attempts have been made to replace individual, omitted tasks of conventional power plants separately. Batteries were built that can only generate primary control power.

In contrast to conventional power plants, the new storage power plants no longer have flywheels due to their system. Conventional power plants, on the other hand, will decrease in number. That's why they have to Storage power plants take over all the tasks of conventional power plants with flywheels.

A system chain of the new "conventional" power plants includes (using the example of a sudden power requirement):

Conversion / adaptation: The sudden electrical power requirement leads to an instantaneous increase in the three-phase current and thus also to an instantaneous increase in the direct current on the direct current side of the converter when the grid voltage angle is kept constant (grid-forming).

Storage: The storage, a super capacitor, stores electrical energy instantaneously and delivers this power. This reduces its voltage, which here characterizes the size of the memory content. This behavior corresponds to the instantaneous reserve of the conventional power plant.

Conversion / adaptation: The control of the downstream DC / DC converter should keep the capacitor voltage constant. To do this, it accesses the battery, which increases the battery current in a matter of seconds. This increases the capacitor charging current and replenishes the voltage store. This behavior corresponds to the primary control of the conventional power plant.

Storage: Due to the increased battery current, the battery voltage drops, which here indicates the size of the storage contents.

Conversion / adaptation: A fuel cell regulator increases the activity of the fuel cell in order to charge the battery and regulate the battery voltage. More hydrogen 2H2 is converted to H2O with oxygen O2. The DC / DC converter adjusts the voltages. The voltage storage device is refilled with the increased battery charging current.

Storage: The fuel cell regulator accesses the hydrogen storage within minutes and increases the fuel mass flow. The hydrogen mass of the storage device is reduced, which here characterizes the size of the storage capacity. Recharge can take place here.

In order to be able to perform all supply and control tasks in the existing frequency-controlled energy supply system, the storage power plant must be able to react to the network frequency and its derivation with the delivery of primary control and instantaneous reserve power

In an energy supply with predominantly storage power plants and only a few or no more conventional power plants with a flywheel, the "Watt speed control" can be dispensed with and the three-phase network can be operated with a constant frequency of e.g. f0 = 50 Hz. The grid control tasks such as instantaneous reserve and primary control power can then be implemented via the voltage angle at the connection point of the storage power plant.

The pamphlets Weber, H .: "From frequency control with flywheels (grid-supporting measures) to angle control with converters (grid-building measures)." (VDI Mecklenburg-Vorpommern i, Dialogue with Politics, Energy Industry and Science, Rostock, October 12, 2017) as Weber, H. [et al.]: "Power System Control with renewable sources, storages and power electronic converters." (In: 2018, IEEE International Conference on Industrial Technology (ICIT), pp. 1272-1278, February 2018, In : IEEE Xplore [online]. DOI: 10.1109 / ICIT.2018.8352361, In: IEEE) system chains of such new “conventional” power plants are revealed.

Presentation of the invention

1. 1 Anschluss des neuen „konventionellen“ Speicherkraftwerks an ein Drehstromnetz, um eine weiträumige und feinverteilte Energieversorgung zu gewährleisten.
2. 2 Plötzliche Laständerungen müssen instantan durch Momentanreserveleistung gespeist werden.
3. 3 Die Speicher der Momentanreserveleistung müssen im Sekundenbereich durch die Primärregelung entlastet und wieder aufgefüllt werden. Dazu werden Primärregelleistungsspeicher benötigt.
4. 4 Die Primärregelleistung muss im Minutenbereich durch die Sekundärregelung abgelöst werden. Dabei ist dann auch deren Speicher wieder aufzufüllen.
5. 5 Anschließend treten Fahrplanänderungen in Kraft.
6. 6 Bei einer voll regenerativ versorgten Energieversorgung müssen definierte Mengen der geernteten Energie für die Prognose von Fehlern sowie für „Dunkelflauten“ gespeichert werden.

It is therefore the task of the invention to eliminate the disadvantages of the prior art and to provide a regulation of new inertia-free storage power plants with which a new "conventional" storage power plant can take over all tasks of network regulation and electrical energy supply in a complete regenerative energy supply. The necessary individual measures that are to be regulated are:

1. 1 Connection of the new “conventional” storage power plant to a three-phase network in order to guarantee a spacious and finely distributed energy supply.
2. 2 Sudden changes in load must be fed instantaneously by instantaneous reserve power.
3. 3 The memory for the instantaneous reserve power must be relieved and refilled within seconds by the primary control. Primary control reserve stores are required for this.
4. 4 The primary control power must be replaced by the secondary control every minute. In doing so, their memory must then also be refilled.
5. 5 Changes to the timetable then come into force.
6. 6 In the case of a fully regenerative energy supply, defined amounts of the harvested energy must be stored for the prognosis of errors as well as for "dark doldrums".

It is the task of the new storage power plant to be regulated in a frequency-regulated or angle-regulated manner.

In the equations given below, all values except angles are given in related quantities.

This problem is solved by the features listed in the claims.

The object is achieved by means of a method for external and internal regulation of a storage power plant without centrifugal masses. For this purpose, the method has the following method steps, it being conceivable to also carry out the method in a sequence other than that described below.

The method for external and internal control of a centrifugal mass-free storage power plant for the provision of system services, which include instantaneous reserve, primary control and secondary control, is divided into an external and an internal control. The external control in turn has an active power control (and a reactive power control) on a DC / AC converter. The active power control has the following procedural steps:

1. a. externe Regelung, welche eine Wirkleistungsregelung an einem DC/AC-Umrichter umfasst:
   • - Auswählen eines Regelungsmodus, wobei ein erster Regelungsmodus eine winkelbasierte Regelung (φ_Reg-Modus) ist und ein zweiter Regelmodus eine frequenzbasierte Regelung (f_Reg-Modus) ist, wobei die frequenzbasierte Regelung folgende Verfahrensschritte aufweist:
     1. i. Messen einer momentan abgegeben Wirkleistung p am DC/AC-Umrichter und Vorgabe einer Änderung einer Kraftwerkssollleistung Δp_H2 anhand eines Inhaltes eines Wasserstoffspeichers,
     2. ii. Bilden einer Regelabweichung Δp aus der gemessenen momentan abgegeben Wirkleistung p mit einer Sollwirkleistung, wobei die Sollwirkleistung eine vorgegebene Sekundärleistungsänderung Δp_sec, eine vorgegebene Fahrplanleistung p_FP und die Vorgabe der Änderung der Kraftwerkssollleistung Δp_H2 aufweist und
     3. iii. Errechnen einer synthetischen Netzwinkelgeschwindigkeit Δω₂ aus der Regelabweichung Δp, wobei die synthetische Winkelgeschwindigkeit Δω₂ zu einer integralen Verstellung des Spannungswinkels φ_U2 am DC/AC-Umrichter führt,

Process for the external and internal control of a centrifugal-free storage power plant for the provision of system services, which include instantaneous reserve, primary control and secondary control,
Process comprising the following process steps:

1. a. External control, which includes active power control on a DC / AC converter:
   • - Selecting a control mode, a first control mode being an angle-based control (φ _Reg mode) and a second control mode being a frequency-based control (f _Reg mode), the frequency-based control having the following method steps:
     1. i. Measurement of a currently emitted active power p on the DC / AC converter and specification of a change in a power plant target output Δp _H2 based on the content of a hydrogen storage tank,
     2. ii. Formation of a control deviation Δp from the measured active power currently emitted p with a target active power, the target active power being a predetermined secondary power change Δp _sec , a predetermined schedule power p _FP and the specification of the change in the power plant target power Δp _H2 has and
     3. iii. Calculating a synthetic network angular velocity Δω ₂ from the control deviation Δp , where the synthetic angular velocity Δω ₂ leads to an integral adjustment of the voltage angle φ _U2 at the DC / AC converter,

• - Festsetzen einer Regelabweichung Δp=0, wobei der Spannungswinkel φ_U2 am DC/AC-Umrichter konstant bleibt und das Speicherkraftwerk als Spannungsquelle mit konstanter Spannung _U2 und konstanter Frequenz von 50 Hz arbeitet,

wobei die winkelbasierte Regelung Sicherungsmechanismen aufweist, welche anhand der gemessenen momentan abgegebenen Leistung p mittels einer Steuerungsseinheit eingeschaltet werden, wobei die Sicherungsmechanismen folgende Varianten umfassen:

• - Manuelle Einstellung einer Leistung pman,
• - Leistungseinstellung anhand eines vordefinierten Leistungsmaximalwertes p_Max und/oder eines vordefinierten Leistungsminimalwertes p_Min und/oder
• - Leistungseinstellung anhand einer Vorgabe einer Änderung einer Kraftwerkssollleistung Δp_H2 anhand eines Inhaltes eines Wasserstoffspeichers,

The angle-based control in Slack mode has the following procedural steps:

• - Establishing a control deviation Δp = 0, whereby the voltage angle φ _U2 at the DC / AC converter remains constant and the storage power plant works as a voltage source with a constant voltage _U2 and a constant frequency of 50 Hz,

wherein the angle-based control has safety mechanisms which are based on the measured power currently output p can be switched on by means of a control unit, the security mechanisms comprising the following variants:

• - Manual setting of a power pman,
• - Power setting based on a predefined maximum power value p _Max and / or a predefined minimum power value p _Min and / or
• - Power setting based on a specification of a change in a power plant target power Δp _H2 based on the content of a hydrogen storage tank,

• - Messen einer momentan abgegeben Blindleistung q₂ am DC/AC-Umrichter
• - Vergleichen der momentan abgegebenen Blindleistung q₂ mit einer Sollblindleistung q₀, wobei eine Differenz gebildet wird mittels welcher und zusammen mit einer vordefinierten Blindleistungsstatik σ_q eine Spannung am Speicherkraftwerk _U2 gebildet wird.

A reactive power control of the external control can have the following method steps according to several embodiments:

• - Measuring a momentarily emitted reactive power q ₂ on the DC / AC converter
• - Compare the reactive power currently emitted q ₂ with a target reactive power q ₀ , a difference being formed by means of which and together with a predefined reactive power statics σ _q a voltage is generated at the storage power plant _U2.

• - Ermitteln eines Gleichstroms i_Kc, welcher von einem ersten Speicher zum DC/AC-Konverter fließt, aus einer gemessenen Speicherspannung uc des ersten Speichers und der Wirkleistung p, wobei der Gleichstrom i_KC und ein von einem zweiten Speicher zum ersten Speicher fließende Strom i_CB die Speicherspannung uc des ersten Speichers integral einstellt.
• - Regeln des Gleichstroms i_CB , welcher vom ersten Speicher zum zweiten Speicher fließt, derart, dass die Speicherspannung uc des ersten Speichers einen Sollwert der Speicherspannung u_c , _soll annimmt
• - Laden des zweiten Speichers mittels eines mit einem ersten Energiewandler erzeugten Gleichstroms i_BF bei Unterschreiten eines ersten Speicherspannungswertes ü_B des zweiten Speichers, wobei ein Entladen eines dritten Speichers erfolgt, oder Entladen des zweiten Speichers mittels eines mit einem zweiten Energiewandler erzeugten Stromes i_EB bei Überschreiten eines zweiten Speicherspannungswertes û_B des zweiten Speichers, wobei ein Laden des dritten Speichers erfolgt.

The internal regulation, which provides the necessary system services from storage, comprises the following procedural steps:

• Determination of a direct current i _Kc , which flows from a first store to the DC / AC converter, from a measured store voltage uc of the first store and the active power p , where the direct current i _KC and a current flowing from a second memory to the first memory i _CB integrally sets the storage voltage uc of the first storage device.
• - Regulating the direct current i _CB , which flows from the first memory to the second memory, such that the memory voltage uc of the first Store a setpoint value of the store voltage u _c , _{supposed to} accept
• - Charging the second memory by means of a direct current generated with a first energy converter i _BF when _{the second storage unit falls below a first storage voltage value U B} , a third storage unit being discharged, or the second storage unit being discharged by means of a current generated by a second energy converter i _EB when a second storage voltage value û _{B of} the second storage device is exceeded, the third storage device being charged.

According to various embodiments, an operating point power p _{AP is} stored for an intervention by the security mechanisms, which is the current power value p at the time of the occurrence of an error and which is used for further procedures in order to ensure a smooth transition from normal operation to minimum / maximum operation.

According to one embodiment, the first memory has a capacitor or the first memory is a capacitor.

According to one embodiment, the second memory has a battery or the second memory is a battery.

According to one embodiment, the third store has a hydrogen store or the third store is a hydrogen store. It is conceivable to use additional or different chemical stores, but the use of mechanical and / or thermal stores is also conceivable. A hydrogen mass can be used here m _H are measured on the hydrogen storage device, the measured hydrogen mass m _H as an input variable for the external active power control for the power specification Δp _H2 is used in the frequency control mode _{f reg} and / or in the angle control _{mode φ reg.}

Furthermore, according to one embodiment, the energy converter has a fuel cell or it is a fuel cell and / or the second energy converter has an electrolyzer or it is an electrolyzer. The use of further and / or different energy converters is conceivable.

According to a further embodiment, a circulating current flows i ₀ between the first energy converter and the second energy converter in order to be able to switch smoothly between the first and the second energy converter.

According to one embodiment, the first storage voltage _{value ŭ B of} the second storage unit is a fixed value of, for example, + 10% of the storage voltage of the second storage unit u _B set and / or the second storage voltage _{value û B of} the second storage as a fixed value to -10% of the storage voltage of the second storage u _B set. These are examples of these thresholds. Their values are set as constant fixed values. Other threshold values which cause the second and / or the third memory to be activated are conceivable.

A conventional power plant can be replaced with the method according to the invention for external and internal control of a storage power plant for the provision of system services which include instantaneous reserve, primary control and secondary control. With the help of the process, the new storage power plant manages without centrifugal masses and can both absorb and absorb power. It either consumes hydrogen or it generates hydrogen. This enables fully regenerative energy generation, in which these new power plants not only store energy, but can also bring in all system services such as instantaneous, primary, secondary control and timetable.

In addition, the power plant can act as a so-called slack power plant in the event of future angular regulation of the electrical network, which enables the electrical energy supply to be stabilized further.

With the use of flywheel-free storage power plants with modern and powerful converter technology, network control can be operated sensibly in both frequency and angle-regulated networks. In frequency-controlled networks with still existing conventional centrifugal masses, these new systems act like normal power plants and can cover all network control tasks such as instantaneous reserve, primary and secondary control as well as schedule operation. In addition, they can also store energy from renewable sources, which can make redispatch actions superfluous. In future, angle-regulated networks without a physical centrifugal mass, these power plants can work as slack storage power plants, which enables a constant network frequency to be maintained. For this, however, the exact measurement of the angle and an angle standard is necessary. This means that all future applications can be covered, which will also enable the further secure expansion of a regenerative energy supply in the future.

It is also a method for the external and internal control of a centrifugal massless storage power plant for the provision of system services, which instantaneous reserve, Primary control and secondary control include disclosed.

• - externe Regelung, welche eine Wirkleistungsregelung und eine Blindleistungsregelung an einem DC/AC-Umrichter umfasst,

wobei die Wirkleistungsregelung folgende Verfahrensschritte aufweist:

• - Messen einer momentan abgegeben Wirkleistung (p) am DC/AC-Umrichter
• - Vergleichen der Wirkleistung (p) mit einer Sollwirkleistung (po), aufweisend einen Primärregelsollwert (p_{0, prim})
• - Bilden einer synthetischen Winkelgeschwindigkeit (Δω₂ ) gemäß $$\Delta {\omega }_2=-\frac{1}{\text{s }{T}_M}\cdot \left(p-p_0\right)$$
  

wobei die synthetische Winkelgeschwindigkeit (Δω₂ ) zu einer integralen Verstellung des Spannungswinkels (φ_U2) führt

• - Bilden eines Primärregelsollwertes (p_{0, prim}) aus einer vordefinierten Wirkleistungsstatik (σ_p ) und der synthetischen Netzwinkelgeschwindigkeit (Δω₂ ) gemäß $${\text{<figure-callout id="0" label="p" filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png" state="{{state}}">p</figure-callout>}}_{\mathrm{0,}\text{prim}}=-\frac{1}{{\mathrm{\sigma }}_{\text{<figure-callout id="2" label="p Δ ω" filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png" state="{{state}}">p</figure-callout>}}}\Delta {\omega }_{}{}_2$$
  

und wobei die Blindleistungsregelung folgende Verfahrensschritte aufweist:

• - Messen einer momentan abgegeben Blindleistung (q₂ ) am DC/AC-Umrichter
• - Vergleichen der momentan abgegebenen Blindleistung (q₂ ) mit einer Sollblindleistung (qo), wobei eine Differenz gebildet wird mittels welcher, zusammen mit einer vordefinierten Blindleistungsstatik (σ_q ), eine Spannung am Speicherkraftwerk (u₂ ) gebildet wird

wobei mit der Spannung (u₂ ) der Blindleistungsregelung und dem Spannungswinkel (φ_U2) der Wirkleistungsregelung zusammen mit einer vordefinierten Netzspannung (_U1) und einer vordefinierten Netzwinkelfrequenz (Δω₁ ) die Wirkleistung (p) geregelt wird

• - interne Regelung: Bereitstellung der Systemdienstleistungen aus Speichern, welche folgende Verfahrensschritte umfasst:
  • - Ermitteln eines Gleichstroms (i_KC ), welcher von einem ersten Speicher zum DC/AC-Konverter fließt, aus einer gemessenen Speicherspannung (uc) des ersten Speichers und der Wirkleistung (p), wobei der Gleichstrom (i_KC ) und ein von einem zweiten Speicher zum ersten Speicher fließende Strom (i_CB ) die Speicherspannung (u_C) des ersten Speichers integral einstellt
  • - Regeln des Gleichstroms (i_CB ), welcher vom ersten Speicher zum zweiten Speicher fließt, derart, dass die Speicherspannung (u_C) des ersten Speichers einen Sollwert der Speicherspannung (u_{C, soll}) annimmt
  • - Laden des zweiten Speichers mittels eines mit einem ersten Energiewandler erzeugten Gleichstroms (i_BF ) bei Unterschreiten eines ersten Speicherspannungswertes (ŭ_B) des zweiten Speichers, wobei ein Entladen eines dritten Speichers erfolgt, oder Entladen des zweiten Speichers mittels eines mit einem zweiten Energiewandler erzeugten Stromes (i_EB ) bei Überschreiten eines zweiten Speicherspannungswertes (û_B) des zweiten Speichers, wobei ein Laden des dritten Speichers erfolgt.

Process comprising the following process steps:

• - external control, which includes active power control and reactive power control on a DC / AC converter,

where the active power control has the following procedural steps:

• - Measurement of a currently emitted active power ( p ) on the DC / AC converter
• - Compare the active power ( p ) with a setpoint active power (po), having a primary control setpoint (p _{0, prim} )
• - Formation of a synthetic angular velocity ( Δω ₂ ) according to $$\Delta {\omega }_2=-\frac{1}{\text{s}{T}_{\mathrm{M.}}}\cdot \left(p-p_0\right)$$
  

where the synthetic angular velocity ( Δω ₂ ) leads to an integral adjustment of the voltage angle (φ _U2 )

• - Formation of a primary control setpoint (p _{0, prim} ) from a predefined active power statics ( σ _p ) and the synthetic network angular velocity ( Δω ₂ ) according to $${\text{<figure-callout id="0" label="p" filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png" state="{{state}}">p</figure-callout>}}_{\mathrm{0,}\text{prim}}=-\frac{1}{{\mathrm{\sigma }}_{\text{<figure-callout id="2" label="p Δ ω" filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png" state="{{state}}">p</figure-callout>}}}\Delta {\omega }_{}{}_2$$
  

and wherein the reactive power control has the following method steps:

• - Measurement of a currently emitted reactive power ( q ₂ ) on the DC / AC converter
• - Compare the reactive power currently output ( q ₂ ) with a target reactive power (qo), whereby a difference is formed by means of which, together with a predefined reactive power statics ( σ _q ), a voltage at the storage power plant ( u ₂ ) is formed

where with the voltage ( u ₂ ) the reactive power control and the voltage _{angle (φ U2} ) of the active power control together with a predefined grid voltage ( _U1 ) and a predefined grid angular frequency ( Δω ₁ ) the active power ( p ) is regulated

• - Internal regulation: Provision of system services from storage facilities, which includes the following procedural steps:
  • - determining a direct current ( i _KC ), which flows from a first store to the DC / AC converter, from a measured store voltage (uc) of the first store and the active power ( p ), where the direct current ( i _KC ) and a current flowing from a second memory to the first memory ( i _CB ) integrally sets the storage voltage (u _C ) of the first storage device
  • - regulating direct current ( i _CB ), which flows from the first memory to the second memory, in such a way that the memory voltage (u _C ) of the first memory assumes a nominal value of the memory voltage (u _{C, soll)}
  • - Charging the second storage unit by means of a direct current generated by a first energy converter ( i _BF ) when the second storage unit falls below a first storage voltage value (ŭ _B ), whereby a third storage unit is discharged, or the second storage unit is discharged by means of a current generated by a second energy converter ( i _EB ) when a second memory voltage value (û _B ) of the second memory is exceeded, the third memory being charged.

Figure list

• 1 Blockschaltbild der vollständigen Wirkleistungsregelung des Speicherkraftwerkes
• 2 Blockschaltbild zur Blindleistungsregelung
• 3 Darstellung des Kurzzeitverhaltens bei einer erfindungsgemäßen Regelung
• 4 Darstellung des Langzeitverhaltens bei einer erfindungsgemäßen Regelung
• 5 Blockschaltbild der externen p-Regelung für Frequenz- und Winkelregelung des Speicherkraftwerks (a)
• 6 Anlagenschema des Speicherkraftwerks (b)
• 7 Interne Regelung eines ersten Speichers am Beispiel eines Superkondensators (c1)
• 8 Interne Regelung eines zweiten Speichers am Beispiel einer Batterie (c2)
• 9 Interne Regelung eines ersten und zweiten Energiewandlers an den Beispielen eines Elektrolyseurs und einer Brennstoffzelle (c3)

The invention is explained in more detail using exemplary embodiments. Show this

• 1 Block diagram of the complete active power control of the storage power plant
• 2 Block diagram for reactive power control
• 3 Representation of the short-term behavior with a control according to the invention
• 4th Representation of the long-term behavior with a control according to the invention
• 5 Block diagram of the external p-control for frequency and angle control of the storage power plant ( a )
• 6th System scheme of the storage power plant ( b )
• 7th Internal control of a first storage tank using the example of a supercapacitor ( c1 )
• 8th Internal control of a second storage tank using the example of a battery ( c2 )
• 9 Internal control of a first and second energy converter using the examples of an electrolyzer and a fuel cell ( c3 )

• - die Bereitstellung einer Momentanreserve, um plötzliche Laständerungen instant zu speisen,
• - die Bereitstellung einer Primärregelleistung, um einen Momentanreserve-Speicher im Sekundenbereich zu entlasten und wieder aufzufüllen,
• - die Bereitstellung einer Sekundärregelleistung, welche die Primärregelung nach einer bestimmten Zeit im Minutenbereich ablöst und um einen Primärregelungsspeicher wieder aufzufüllen
• - Bereitstellung von Fahrplanänderungen, welche alle Regler wieder auf „Null“ stellen

The method according to the invention for regulating a new storage power plant is divided into an internal and an external regulation of a storage power plant for the provision of
System services.
System services are

• - the provision of an instantaneous reserve to feed sudden load changes instantaneously,
• - the provision of a primary control power in order to relieve a momentary reserve memory in the range of seconds and to fill it up again,
• - The provision of a secondary control power, which replaces the primary control after a certain time in the range of minutes and to refill a primary control memory
• - Provision of schedule changes which reset all controllers to "zero"

The external control, in turn, is divided into active power control and reactive power control.

In 1 the frequency-controlled active power control of the storage power plant is shown, consisting of the external frequency-controlled active power setting and the internal active power supply.

wird bei Veränderung der momentan abgegebenen Leistung p eine Drehzahländerung (Schwungmassen-Drehzahländerung) simuliert. Dies führt dahingehend zu einer integralen Verstellung des Spannungswinkels φ_u2 am DC/AC-Wandler gemäß $$\Delta {\phi }_{u_2}={\Omega }_0{\displaystyle \int \Delta {\omega }_2\cdot dt}$$

und $${\Omega }_0=2\cdot \pi \cdot f_0$$

so dass die Schwankungen möglichst klein gehalten werden und es wieder gilt $$\text{p}-{\text{p}}_0=0$$

The storage power plant, for example a capacitor, is connected to the three-phase network via a DC / AC converter and feeds active power p a. This includes a voltage angle φ _U. This voltage angle φ _U is formed on the one hand from the voltage angle φ _{U1 of} the voltage u ₁ of the network center and on the other hand from the voltage angle φ _{U2 of} the voltage _U2 at the storage power plant. The real power p is measured and with a nominal active power p ₀ compared. How out 1 the target active power is evident p ₀ composed of the primary control power, secondary control power and schedule. The schedule output is the output planned by the power plant operator. Primary and secondary control power are the power units that are required to keep the grid stable, with the two power units differing in their time range. The primary control power is the faster power part, which has to compensate for rapid changes in the power requirement. While the centrifugal mass of the rotors works like an instantaneous reserve in conventional power plants, these power components must be modulated to the output in new centrifugal-less storage power plants. In this case, the active power currently being output is used first p measured and with a setpoint of the active power p ₀ compared. With the synthetic equation of motion $$\Delta {\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">\omega </figure-callout>}}_2=-\frac{1}{T_{\mathrm{M.}}}\cdot \left(p-p_0\right)$$

is changed when the current output is changed p a speed change (flywheel speed change) is simulated. This leads to an integral adjustment of the voltage _angle φ u2 at the DC / AC converter according to FIG $$\mathrm{<figure-callout\; id="2"\; label="\Delta \; \phi \; u"\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\phi }_{u_{}}{{}_2}_{}={\mathrm{<figure-callout\; id="0"\; label="\Omega "\; filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png"\; state="\{\{state\}\}">\Omega </figure-callout>}}_0{\displaystyle \int \mathrm{<figure-callout\; id="2"\; label="\Delta \; \omega "\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">\Delta </figure-callout>}{\omega }_{}{}_2\cdot dt}$$

and $${\mathrm{<figure-callout\; id="0"\; label="\Omega "\; filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png"\; state="\{\{state\}\}">\Omega </figure-callout>}}_0=2\cdot \pi \cdot {\mathrm{<figure-callout\; id="0"\; label="f"\; filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png"\; state="\{\{state\}\}">f</figure-callout>}}_0$$

so that the fluctuations are kept as small as possible and it applies again $$\text{p}-{\text{<figure-callout id="0" label="p" filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png" state="{{state}}">p</figure-callout>}}_0=0$$

This is with the time constant T _M Instantaneous reserve power from a memory, for example a capacitor, is stored.

moduliert.Furthermore, the synthetic network angular velocity ω ₂ determined also feeds the primary control. With a specified power plant statics (active power statics), the power section becomes primary control power p _{0, prim} according to $${\text{<figure-callout id="0" label="p" filenames="DE102019124268B4\_0012.png,DE102019124268B4\_0013.png" state="{{state}}">p</figure-callout>}}_{\mathrm{0,}\text{prim}}=-\frac{1}{{\mathrm{\sigma }}_{\text{<figure-callout id="2" label="p Δ ω" filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png" state="{{state}}">p</figure-callout>}}}\Delta {\omega }_{}{}_2$$

modulated.

The voltage angle φ _{U1 of} the voltage u ₁ is the specified angle of the mains voltage. It is followed in a _{controlled manner by the angle φ U2} , the previously described feedback I control acting like a PLL control. The PLL control (English phase-locked loop) is there to influence the phase position and the related network frequency via a closed control loop in such a way that the power plant output is output p the target performance p ₀ follows.

sich die Wirkleistung p ergibt. x ist dabei die bezogene Netzreaktanz.Together with φ _U1 and φ _U2 , the voltage angle φ _{U is} formed, from which by means of the equation $$p=\frac{{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">u</figure-callout>}}_2\cdot u_1}{x}\cdot \text{sin}{\mathrm{\phi }}_{\text{u}}\approx \frac{{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">u</figure-callout>}}_2\cdot u_1}{x}\cdot {\mathrm{\phi }}_{\text{u}}$$

the real power p results. x is the related network reactance.

wobei die Blindleistungsregelung folgende Verfahrensschritte aufweist, wie in 2 dargestellt:The voltage u ₂ follows from the reactive power control, from the equation $$q_{}$$$${}_2=\frac{-{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="DE102019124268B4\_0010.png,DE102019124268B4\_0011.png"\; state="\{\{state\}\}">u</figure-callout>}}_1\cdot u_2}{x}\cdot \text{cos}{\mathrm{\phi }}_{\text{u}}+\frac{{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="DE102019124268B4\_0015.png,DE102019124268B4\_0017.png"\; state="\{\{state\}\}">u</figure-callout>}}_2{}^2}{x}\approx \frac{u_2\left(u_2-u_1\right)}{x}$$

wherein the reactive power control has the following method steps, as in 2 shown:

A momentarily emitted reactive power q ₂ Measurements are taken at the DC / AC converter and compared with a nominal reactive power q ₀ , a difference being formed by means of which, together with a predefined reactive power statics σ _q the voltage at the storage power plant u ₂ educated.

With the tension u ₂ the reactive power control and the voltage angle φ _{U2 of} the active power control together with a predefined grid voltage u ₁ and a predefined network angular frequency Δω ₁ becomes the real power p regulated

With the real power p This is followed by the internal regulation, which includes the provision of system services from storage, for example capacitors, batteries and / or hydrogen storage. For this purpose, the 1 from a measured capacitor voltage uc and the active power p initially a direct current i _KC , which flows from a capacitor to the DC / AC converter, is determined, where the direct current i _KC and a current flowing from a battery to the capacitor i _CB adjusts the capacitor voltage uc integrally.

Furthermore, the direct current i _CB Regulated in such a way that the capacitor voltage uc assumes a setpoint value for the capacitor voltage u _{C, soll} . The capacitor _{voltage u C, should} be, for example, a value of 1pu.

The battery is charged and / or discharged by means of the regulated direct current i _CB , by means of a direct current generated by a fuel cell i _BF According to one embodiment, this takes place when the voltage falls below a first battery voltage value ŭ _B , and / or by means of a current generated with an electrolyzer i _EB According to one embodiment, this takes place when a second battery voltage value û _{B is exceeded.} When the battery is discharged using the electricity generated i _EB According to one embodiment, a hydrogen storage device is charged. With which, depending on the operating situation, the hydrogen storage unit is charged or discharged via the resulting hydrogen mass flow ṁ _H. This can be done, for example, with the control shown and non-linear transmission elements. The use of anti-wind-up measures is also conceivable.

According to one embodiment, a circular current flows i ₀ between the fuel cell and the electrolyser in order to be able to switch smoothly between the fuel cell and the electrolyser.

In 3 are the curves of active and reactive power in the short-term behavior p and q, the curves of the potentials uc, u _B , m _H and the courses of the currents i _C , i _B , i _H and i _KC shown over time with a control according to the invention. Again 3 As can be seen, the capacitor initially takes over almost all of the current (instantaneous reserve). The battery then stores out (primary regulation) and the capacitor current ic decreases. The current of the slow hydrogen storage (secondary control) is not yet active in this time resolution.

In 4th are the in 3 described over a longer period of time. In this example, the active power jumps p for 500 seconds after a rapid settling process from 0 to 0.2 pu, then to be back to zero by 1000 seconds. Then it jumps to -0.2 pu, and then goes back to zero after 1500 seconds. The reactive power only changes by a small amount.

It can also be seen here how, after approx. 100 seconds, the hydrogen storage unit takes over the entire power generation and both the capacitor and the battery with their currents go back to zero. The switching times of the active power can be clearly seen here.

It can be seen from the potential curves that the capacitor with its power supply and supply only has a very short effect. This behavior corresponds to the instantaneous reserve. The capacitor voltage uc also assumes its initial value again and again, which enables the DC / AC converter to operate without interference. The battery voltage u _B however, moves within its limits, which are set to ± 10%, for example. The battery thus feeds power in and out in the time range of the primary control.

The hydrogen storage is always activated when the battery reaches one of its limit values. At the beginning of the period, the storage unit feeds out and delivers the required power, which is why its hydrogen mass value m _H sinks. No power is required in the range of 500 to 1000 seconds, which is why the memory remains constant. The battery stops near its lower voltage. After 1000 seconds, hydrogen is stored again until the power returns to zero at 1500 seconds. The hydrogen storage system does not quite reach its initial value here, as the battery remains charged a little above its starting value.

5 shows a block diagram of an external p-control for frequency and angle control of the storage power plant. The method according to the invention for external and internal regulation of a centrifugal mass-free storage power plant for the provision of system services, which include instantaneous reserve, primary regulation and secondary regulation, has the following method steps:

An external control, which includes an active power control on a DC / AC converter, also has a reactive power control, which is not explained in more detail here, but is explained further above, according to one embodiment. The active power control can either be angle-based (φ _Reg ) or frequency-based ( f _Reg ), whereby between the angle-based control (φ _Reg ) and the frequency-based control ( f _Reg ) can be selected.

• - Messen einer momentan abgegeben Wirkleistung p am DC/AC-Umrichter und Vorgabe einer Änderung einer Kraftwerkssollleistung Δp_H2 anhand eines Inhaltes eines Wasserstoffspeichers,
• - Bilden einer Regelabweichung Δp aus der gemessenen momentan abgegeben Wirkleistung p mit einer Sollwirkleistung, wobei die Sollwirkleistung eine vorgegebene Sekundärleistungsänderung Δp_sec, eine vorgegebene Fahrplanleistung p_FP und die Vorgabe der Änderung der Kraftwerkssollleistung Δp_H2 aufweist und
• - Errechnen einer synthetischen Netzwinkelgeschwindigkeit Δω₂ aus der Regelabweichung Δp, wobei die synthetische Winkelgeschwindigkeit ω₂ zu einer integralen Verstellung des Spannungswinkels φ_U2 am DC/AC-Umrichter führt.

The frequency-based control regulates the network frequency in the network by increasing the power to be fed in at a low network frequency or by reducing the power to be fed in at an increased network frequency. The frequency-based network control has the following procedural steps:

• - Measurement of a currently emitted active power p on the DC / AC converter and specification of a change in a power plant target output Δp _H2 based on the content of a hydrogen storage tank,
• - Formation of a control deviation Δp from the measured active power currently emitted p with a target active power, the target active power being a predetermined secondary power change Δp _sec , a predetermined schedule power p _FP and the specification of the change in the power plant target power Δp _H2 has and
• - Calculation of a synthetic network angular velocity Δω ₂ from the control deviation Δp , where the synthetic angular velocity ω ₂ leads to an integral adjustment of the voltage _{angle φ U2} at the DC / AC converter.

In order to prevent the voltage angle φ _U2 to be set from oscillating, at least damping is used.

• Festsetzen einer Regelabweichung Δp=0, wobei der Spannungswinkel φ_U2 am DC/AC-Umrichter konstant bleibt und das Speicherkraftwerk als Spannungsquelle mit konstanter Spannung u₂ und konstanter Frequenz von 50 Hz arbeitet. Das bedeutet für netzbildende Umrichter der Slack-Speicherkraftwerke, dass sie ihre Spannungen nach Betrag und Winkel konstant halten können, was einem Slack-Knoten (eingeprägte Spannung) entspricht.

The angle-based control normally works in Slack mode and has the following procedural steps:

• Establishing a control deviation Δp = 0, whereby the voltage angle φ _U2 at the DC / AC converter remains constant and the storage power plant as a voltage source with constant voltage u ₂ and constant frequency of 50 Hz works. For grid-forming converters of the Slack storage power plants, this means that they can keep their voltages constant in terms of magnitude and angle, which corresponds to a Slack node (impressed voltage).

In order _{to prevent the voltage angle φ U2} on the DC / AC converter from oscillating, the active power control system, which is only relevant for frequency control and angle control in the event of a fault, has at least one damping. For example, as in 6th shown, take place by means of a proportional feedback Δp _prim over a permanent statics. For an even higher level of security, further damping can be integrated, for example in 6th shown, according to which a large transient damping prevents an overshoot of the voltage angle φ _U2 even more reliably by means of a further feedback of the controlled variable Δp _{trans via a transient droop.}

1. a. Manuelle Einstellung einer Leistung,
2. b. Leistungseinstellung anhand eines vordefinierten Leistungsmaximalwertes (p_Max) und/oder eines vordefinierten Leistungsminimalwertes (p_Min) und/oder
3. c. Leistungseinstellung anhand einer Vorgabe einer Änderung einer Kraftwerkssollleistung anhand eines Inhaltes eines Wasserstoffspeichers.

Angle-based regulation must be monitored, otherwise the power output or consumption can become too great in Slack mode. For these cases, the angle-based regulation has safety mechanisms, which are based on the measured power currently output p be switched on by means of a control unit and / or circuit unit, the security mechanisms comprising the following variants:

1. a. Manual setting of a power,
2. b. Power setting based on a predefined maximum power value (p _Max ) and / or a predefined minimum power value (p _Min ) and / or
3. c. Power setting based on a specification of a change in a power plant target power based on the content of a hydrogen storage tank.

5 also shows an example in a switch diagram how corresponding switches (for example S1, S2, S3, S4) are switched by means of the control unit if, for example, the power is to be entered manually and / or the power has a certain maximum or minimum value of the permitted power ( p _Min , p _Max ).

6th shows a system diagram of a storage power plant which is controlled by means of the method according to the invention. A real power p (as well as a reactive power q, not shown here) of a three-phase system is used for external regulation of the storage power plant as an input variable for regulating the voltage angle φ _U2 , which is set at the storage power plant. The initial quantity hydrogen mass m _H of the storage power plant is also used for external control as a control variable in order to set the voltage angle φ _U2 based on the level of a hydrogen storage tank or the like.

The mode of operation of the system diagram shown behaves like that in 1 described mode of action. The representation of the mode of operation of the storage power plant selected here is clearer than that in 1 Variant shown, as a distinction is made here between physical units (hardware) and control algorithms. The output variable mH and the input variable φ _U2 , which follows from the external active power control, are also shown here. The control systems of the three storage tanks are shown in further figures as follows: 7 (c1) shows an example of an internal regulation of the first store, for example a supercapacitor, 8 (c2) shows an example of the internal regulation of the second memory, for example a battery and 9 (c3) shows an example of the internal regulation of the first and the second energy converter, for example an electrolyzer and the fuel cell.

List of reference symbols

a

external p-control for frequency and angle control

b

System diagram of the storage power plant

c

Regulation of individual components of the storage power plant

c1

Supercapacitor control

c2

Regulation battery

c3

Control of fuel cell / electrolyser

fReg

Frequency control mode

ϕU

Tension angle

ϕU1

Tension angle of tension u ₁ at the network center

ϕU2

Tension angle of tension u ₂ at the storage power plant

ϕReg

Angle control mode

u1

Network center voltage

u2

Voltage at the storage power plant

uB

Battery voltage

ûB

Battery voltage maximum value

ǔB

Battery voltage minimum value

uc

Capacitor voltage

uc, 0

Setpoint capacitor voltage

iKC

Direct current from the capacitor to the DC / AC converter

iCB

Direct current from the battery to the capacitor

iBF

Direct current from the fuel cell to the battery

iEB

Direct current from the battery to the electrolyzer

i0

Circulating current

iC

Capacitor current

iB

Battery power

iH

Electricity from the fuel cell or the hydrogen storage system

p

Real power

p0

Target active power

pprim

Primary control setpoint

psec

Secondary control setpoint

pFp

or

p0, FP

Timetable

ptrans

transient power

pman

Manual setting of a service

p̌̌Man

= p _Min , minimum permitted capacity of the storage power plant

p̂Man

= p _Max , maximum permitted output of the storage power plant

Δp

Control deviation

ΔpH2

Specification of a change in a power plant target output

Δωe

Angular velocity of the network frequency

Δω1

Angular speed of the PLL control

Δω2

synthetic network angular velocity

TM

Time constant instantaneous reserve

TB

Time constant battery

TC

Time constant capacitor

TH

Time constant hydrogen storage

TBF

Time constant control fuel cell battery

TEB

Time constant regulation of battery electrolyser

KBF

Reinforcement scheme fuel cell battery

KEB

Reinforcement scheme battery electrolyser

σq

Reactive power statics

σp

Active power statics

S.

Laplace operator

X

Network reactance

Ω0

Nominal angular velocity for 50 Hertz

q2

Reactive power at the DC / AC converter

q2, 0

Target reactive power at the DC / AC converter

mH

_{Hydrogen mass} with limit values m Hmax (= m̂ _H ) and m _Hmin

ṁH

Hydrogen mass flow

1, 2, 3, 4, 5

Transfer points

Claims (9)

A method for external and internal control of a flywheel-free storage power plant for the provision of system services which include instantaneous reserve, primary control and secondary control, a method comprising the following procedural steps: external control, which includes active power control on a DC / AC converter: selecting a control mode, with a The control mode is an angle-based control (φ _Reg mode) and a second control mode is a frequency-based control (f _Reg mode), the frequency-based control having the following procedural steps: Measuring a currently emitted active power (p) at the DC / AC converter and Specification of a change in a power plant setpoint power (Δp _H2 ) based on the content of a hydrogen storage tank, - Formation of a control deviation (Δp) from the measured active power output (p) at the moment with a setpoint active power, the setpoint active power being a specified secondary power change (Δp _sec ), a preset given schedule power (p _FP ) and the specification of the change in the power plant's target power (Δp _H2 ) and - calculation of a synthetic network angular velocity (Δω ₂ ) from the control deviation (Δp), whereby the synthetic angular velocity (Δω ₂ ) results in an integral adjustment of the voltage angle ( φ _U2 ) on the DC / AC converter, the angle-based control in Slack mode having the following procedural steps: - Setting a control deviation Δp = 0, where the voltage angle (φ _U2 ) at the DC / AC converter remains constant and the storage power plant as Voltage source works with constant voltage (u ₂ ) and constant frequency of 50 Hz, the angle-based regulation having safety mechanisms which are switched on by means of a control unit based on the measured momentarily output power p, the safety mechanisms comprising the following variants: - Manual setting of a power ( p _man ), - power setting based on a predefined rth maximum power value (p _Max ) and / or a predefined _{minimum power value (p Min} ) and / or - power setting based on a specification of a change in a power plant target power (Δp _H2 ) based on the content of a hydrogen storage tank, - internal control: provision of system services from storage facilities, which follow Method steps comprise: - Determination of a direct current (i _KC ), which flows from a first memory to the DC / AC converter, from a measured memory _{voltage (u c} ) of the first memory and the active power (p), the direct current (i _KC ) _{and a current (i CB} ) flowing from a second memory to the first memory integrally sets the memory voltage (u _c ) of the first memory - regulating the direct current (i _CB ) flowing from the first memory to the second memory in such a way that the memory voltage ( u _c ) of the first memory assumes a nominal value of the memory voltage (u _{c, soll} ) - loading the second memory by means of a _{s direct current (i BF} ) generated with a first energy converter when the voltage falls below a first storage _{voltage value (ŭ B} ) of the second storage unit, whereby a third storage unit is discharged, or the second storage unit is discharged by means of a current (i _EB ) generated by a second energy converter Exceeding a second memory voltage value (û _B ) of the second memory, the third memory being charged. Procedure according to Claim 1 , characterized in that for an intervention of the Security mechanisms a working point performance (p _AP ) is saved / kept. Procedure according to Claim 1 , characterized in that the first memory has a capacitor. Procedure according to Claim 1 or 2 , characterized in that the second memory has a battery. Method according to one of the preceding claims, characterized in that the third store is the hydrogen store. Method according to one of the preceding claims, characterized in that a hydrogen mass (m _H ) is measured on the hydrogen storage device, the measured hydrogen mass (m _H ) as an input variable for the external active power control in the frequency control mode (f _reg ) and / or angle control mode (φ _reg ) is used. Method according to one of the preceding claims, characterized in that the first energy converter has a fuel cell. Method according to one of the preceding claims, characterized in that the second energy converter has an electrolyzer. Method according to one of the preceding claims, characterized in that a circulating current (i ₀ ) flows between the first energy converter and the second energy converter in order to be able to switch smoothly between the first energy converter and the second energy converter.

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