CN114285067A - Fault ride-through method, device and storage medium - Google Patents
Fault ride-through method, device and storage medium Download PDFInfo
- Publication number
- CN114285067A CN114285067A CN202111667691.7A CN202111667691A CN114285067A CN 114285067 A CN114285067 A CN 114285067A CN 202111667691 A CN202111667691 A CN 202111667691A CN 114285067 A CN114285067 A CN 114285067A
- Authority
- CN
- China
- Prior art keywords
- voltage
- current
- direct
- alternating
- oil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 57
- 230000005540 biological transmission Effects 0.000 claims abstract description 76
- 230000015654 memory Effects 0.000 claims description 20
- 238000011084 recovery Methods 0.000 claims description 18
- 230000003044 adaptive effect Effects 0.000 claims description 5
- 238000004364 calculation method Methods 0.000 claims description 4
- 238000001514 detection method Methods 0.000 claims description 4
- 238000005553 drilling Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 8
- 238000005259 measurement Methods 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 238000012545 processing Methods 0.000 description 5
- 238000004891 communication Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000001960 triggered effect Effects 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000004590 computer program Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000013528 artificial neural network Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000013135 deep learning Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000013024 troubleshooting Methods 0.000 description 1
Images
Classifications
-
- 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
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Inverter Devices (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention provides a fault ride-through method, a fault ride-through device and a storage medium, which are used for a flexible direct-current power transmission system for supplying power to an oil and gas drilling platform (an oil and gas platform for short), wherein the flexible direct-current power transmission system comprises an alternating-current power grid side converter station, an oil and gas platform side converter station and a direct-current cable for connecting the two converter stations, and the method comprises the following steps: detecting the direct-current voltage of a converter station of the oil-gas platform; judging whether the direct current voltage is lower than a preset direct current voltage threshold value or not; when the direct current voltage is lower than the direct current voltage threshold value, calculating an alternating current voltage adjustment amount; and controlling the alternating voltage output by the oil-gas platform side converter station to be reduced according to the alternating voltage adjustment quantity. The problem of oil gas platform alternating current power grid fault ride through that supplies power through flexible direct current transmission system among the prior art is solved.
Description
Technical Field
The invention relates to the technical field of flexible direct current transmission, in particular to a fault ride-through method, a fault ride-through device and a storage medium.
Background
The flexible direct current transmission technology is a new generation high-voltage direct current transmission technology based on a voltage source converter, a self-turn-off device (IGBT) and a Pulse Width Modulation (PWM) technology. Compared with the traditional high-voltage direct-current transmission, the flexible direct-current transmission technology has strong controllability, the turn-off device can perform complete control on and off, and the alternating-current side is not required to provide commutation current, so that the problem of commutation failure does not exist; due to complete control, the flexible direct current transmission does not need a large amount of reactive power support on the alternating current side, and the occupied area is reduced; the passive characteristic can finish power supply to an island (power supply of a small power grid in an area connected by only a few power transmission lines), and the problem of the last kilometer in a weak area of the net rack is solved; the switching frequency of the full-control device is extremely high, thousands of hertz moves very often, only need a small amount of high-order filters to finish filtering, have avoided the pollution of the low-order harmonic to the electric wire netting. For the Chinese power grid, the frequency of the alternating current power grid is 50 Hz, so that the low harmonic waves are more difficult to process than the high harmonic waves. The power flow of the flexible direct current transmission technology is reversed rapidly, the current of the flexible direct current transmission system can flow in two directions, and meanwhile, the positive pole and the negative pole of the direct current voltage are kept unchanged. When the conventional direct current power flow is reversed, the polarity of the direct current voltage is reversed, and the direction of the direct current is unchanged. In a parallel multi-terminal direct-current transmission system, a flexible direct-current transmission system can change the direction of a power flow by changing the direction of a single-terminal current, and the flexible direct-current transmission system has a multi-point transmission function. Therefore, the flexible direct-current transmission technology is very suitable for supplying power to such passive networks as disconnected power grids with no power generation units, isolated island power grids, offshore oil and gas platforms and the like.
In the scene that the flexible direct-current transmission technology is applied to the oil-gas platform power supply system, the tide of the whole system only exists in a single direction from the alternating-current power grid side converter station to the oil-gas platform side converter station, so that when the alternating-current power grid side fails, the alternating-current voltage of the alternating-current power grid rapidly drops, and the power input into the flexible direct-current transmission system is reduced. Because the alternating voltage (and frequency) output by the converter station at the oil-gas platform side is used for controlling equipment at the oil-gas platform side, the converter station at the oil-gas platform side cannot directly feel fault information at the alternating current power grid side, so that the oil-gas platform side still continues to draw constant power from the flexible direct current transmission system within a time period before the fault is known, and further the power of a transmitting end and the power of a receiving end of the flexible direct current transmission system are unbalanced. The output power of the oil and gas platform side is greater than the input power of the alternating current network side, which will result in the reduction of the direct current voltage. If the drop of the direct-current voltage cannot be effectively inhibited, direct-current voltage under-voltage protection is triggered, the shutdown of the whole flexible direct-current power transmission system is caused, and then all loads on the oil-gas platform side are tripped. The existing scheme is that fault information is transmitted to an oil-gas platform side by an alternating current power grid side in a communication mode, and then corresponding loads are cut off through targeted processing and scheduling of the oil-gas platform side, so that power balance of a transmitting end and a receiving end is guaranteed. However, this solution is too communication-dependent and requires a relatively long processing time from accurate fault determination on the ac grid side to load shedding on the oil and gas platform side, i.e. protection is triggered before the load is processed, so that the entire flexible dc transmission system is still forced to be shut down, which seriously affects the operational reliability of the flexible dc transmission system.
Disclosure of Invention
In view of the above, embodiments of the present invention provide a fault ride-through method, apparatus and storage medium to solve the above problems.
In a first aspect, a fault ride-through method provided by an embodiment of the present invention is used for a flexible direct current transmission system for supplying power to an oil and gas platform, where the flexible direct current transmission system includes an alternating current grid-side converter station, an oil and gas platform-side converter station, and a direct current cable connecting the two converter stations, and the fault ride-through method includes:
detecting the direct-current voltage of a converter station of the oil-gas platform;
judging whether the direct current voltage is lower than a preset direct current voltage threshold value or not;
when the direct-current voltage is lower than the direct-current voltage threshold value, calculating an alternating-current voltage adjustment quantity, wherein the alternating-current voltage adjustment quantity is adaptive to the variation of the direct-current voltage relative to a reference direct-current voltage, and the reference direct-current voltage is the direct-current voltage output by the alternating-current power grid side converter station in the stable state of the flexible direct-current transmission system;
and controlling the alternating voltage output by the oil-gas platform side converter station to be reduced according to the alternating voltage adjustment quantity.
Preferably, when the dc voltage is lower than the dc voltage threshold, calculating an ac voltage adjustment amount includes:
calculating a difference value between the direct current voltage and a reference direct current voltage based on a preset reference direct current voltage;
and converting by using the difference value to obtain the alternating voltage adjustment quantity.
Preferably, the ac voltage adjustment amount is calculated by the following formula:
△V＝KM(Vdcref-Vdc)
wherein Δ V represents an AC voltage adjustment amount, KMRepresents the gain factor, (V)dcref-Vdc) Representing the difference, V, between the reference DC voltage and the actual DC voltagedcrefRepresenting a reference DC voltage, VdcRepresenting the actual dc voltage.
Preferably, the fault ride-through method further comprises:
and when the direct-current voltage is not lower than the direct-current voltage threshold value, controlling the oil-gas platform side converter station to output alternating-current voltage according to preset reference alternating-current voltage, wherein the reference alternating-current voltage is the alternating-current voltage output by the oil-gas platform side converter station in a stable state of the flexible direct-current transmission system.
Preferably, after controlling the alternating-current voltage output by the oil and gas platform side converter station to be reduced according to the alternating-current voltage adjustment amount, the fault ride-through method further includes:
calculating a recovery adjustment amount;
and controlling the alternating voltage output by the oil-gas platform side converter station to be gradually boosted according to the recovery adjustment amount.
Preferably, the calculating the restoration adjustment amount includes:
detecting the current direct-current voltage of the oil-gas platform converter station again;
calculating a difference between the DC voltage and the current DC voltage based on the DC voltage and the current DC voltage;
and converting the difference value of the direct current voltage and the current direct current voltage to obtain the recovery adjustment quantity.
Preferably, after the controlling the alternating-current voltage output by the oil and gas platform side converter station to be gradually boosted according to the recovery adjustment amount, the fault ride-through method further includes:
and after the fault is determined to be completely cleared, controlling the alternating-current voltage output by the oil-gas platform side converter station to be gradually boosted to the reference alternating-current voltage.
In a second aspect, a fault ride-through device provided in an embodiment of the present invention is a flexible dc power transmission system for supplying power to an oil and gas platform, where the flexible dc power transmission system includes an ac power grid-side converter station, an oil and gas platform-side converter station, and a dc cable connecting the two converter stations, and the fault ride-through device includes:
the detection module is used for detecting the direct-current voltage of the oil-gas platform converter station;
the judging module is used for judging whether the direct current voltage is lower than a preset direct current voltage threshold value;
the calculation module is configured to calculate an ac voltage adjustment amount when the dc voltage is lower than the dc voltage threshold, where the ac voltage adjustment amount is adapted to a variation amount of the dc voltage with respect to a reference dc voltage, where the reference dc voltage is a dc voltage output by the ac power grid side converter station in a stable state of the flexible dc power transmission system;
and the control module is used for controlling the alternating-current voltage output by the oil-gas platform side converter station to be reduced according to the alternating-current voltage adjustment quantity.
In a third aspect, a fault ride-through device provided according to an embodiment of the present invention includes: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory having stored therein computer instructions, and the processor implementing the fault-ride-through method of any one of the first aspect by executing the computer instructions.
In a fourth aspect, a non-transitory computer-readable storage medium is provided according to an embodiment of the present invention, the non-transitory computer-readable storage medium storing computer instructions that, when executed by a processor, implement the fault-ride-through method of any one of the first aspects.
The fault ride-through method, the fault ride-through device and the storage medium provided by the embodiment of the invention at least have the following beneficial effects:
according to the fault ride-through method, the fault ride-through device and the storage medium, whether the alternating current power grid side has a fault or not is determined by detecting the direct current voltage of the oil-gas platform converter station and judging whether the direct current voltage is lower than a preset direct current voltage threshold value or not. And when the direct-current voltage is lower than the direct-current voltage threshold value, namely when the alternating-current power grid side is judged to have a fault, controlling the alternating-current voltage output by the oil-gas platform side converter station to be reduced by calculating the alternating-current voltage adjustment amount and controlling the alternating-current voltage according to the alternating-current voltage adjustment amount. The corresponding alternating-current voltage adjustment quantity is obtained through adaptive calculation of the direct-current voltage relative to the variable quantity of the reference direct-current voltage, so that the alternating-current voltage output by the oil-gas platform side converter station is accurately reduced, the problem that the direct-current voltage output by the alternating-current power grid side converter station is reduced due to the fact that faults are responded to the alternating-current power grid side is solved, the power balance of a sending end and a receiving end is guaranteed, direct-current voltage under-voltage protection is prevented from being triggered, the whole flexible direct-current power transmission system is prevented from being forced to stop running, the whole flexible direct-current power transmission system can smoothly transmit power, and the running reliability of the flexible direct-current power transmission system is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a flowchart of a fault ride-through method according to an embodiment of the present invention;
FIG. 2 is a block diagram of a flexible DC power transmission system for supplying power to an oil and gas platform according to an embodiment of the present invention;
fig. 3 is a block diagram of a control system of a converter station on the ac power grid side according to an embodiment of the present invention;
FIG. 4 is a block diagram of a control system of a converter station at the oil and gas platform side according to an embodiment of the present invention;
FIG. 5 is a block diagram of a fault ride-through device according to an embodiment of the present invention;
fig. 6 is a block diagram of a fault ride-through device according to an embodiment of the present invention.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Example 1
Referring to fig. 1 and fig. 2, fig. 1 is a flowchart of a fault ride-through method provided by an embodiment of the invention, and fig. 2 is a block diagram of a flexible direct current transmission system for supplying power to an oil and gas platform provided by an embodiment of the invention. Although the processes described below include multiple operations that occur in a particular order, it should be clearly understood that the processes may include more or fewer operations that are performed sequentially or in parallel.
In the flexible dc power transmission system for supplying power to an oil and gas platform shown in fig. 2, a sending end and a receiving end may be included, where the sending end is an ac power grid side and the receiving end is an oil and gas platform side. The alternating current generated by the alternating current network on the alternating current network side is converted into direct current by the alternating current network side converter station and is transmitted to the direct currentAn oil gas platform side converter station; the converter station at the side of the oil-gas platform receives direct current, and converts the direct current into alternating current for the oil-gas platform to use. Generally, at least one of the transmitting terminal and the receiving terminal adopts a constant DC voltage control method. In the flexible direct-current transmission system for supplying power to the oil and gas platform shown in fig. 2, a constant direct-current voltage control mode and a constant reactive power control mode are adopted in an alternating-current power grid side converter station, and a control block diagram of the system is shown in fig. 3; the oil gas platform side converter station adopts a constant alternating voltage control mode, the control block diagram is shown as figure 4, and u in figure 4d_refIs a d-axis component reference value u of the output AC voltage in dq rotation coordinate systemq_refIs a q-axis component reference value of the output alternating voltage in a dq rotation coordinate system. The fixed direct-current voltage control mode is beneficial to improving the stability of alternating-current voltage of the convertor station by keeping the voltage equal to the setting value of the voltage regulator. Namely, when a fault occurs at the oil-gas platform side, the flexible direct current transmission system adaptively controls the direct current voltage output by the alternating current network side converter station to realize the adaptive adjustment of power transmission, so that the change of power caused by the fault at the oil-gas platform side is met adaptively, and the voltage change of the flexible direct current transmission system is ensured not to trigger a protection mechanism.
Referring to fig. 1, an embodiment of the present invention further provides a fault ride-through method, where the fault ride-through method is used for a flexible direct-current power transmission system powered by an oil and gas platform, where the flexible direct-current power transmission system includes an alternating-current power grid-side converter station, an oil and gas platform-side converter station, and a direct-current cable connecting the two converter stations, and the fault ride-through method includes the following steps:
s101, detecting direct-current voltage of a converter station of an oil-gas platform;
step S102, judging whether the direct current voltage is lower than a preset direct current voltage threshold value;
step S103, when the direct-current voltage is lower than the direct-current voltage threshold value, calculating an alternating-current voltage adjustment amount, wherein the alternating-current voltage adjustment amount is adapted to a variation of the direct-current voltage relative to a reference direct-current voltage, and the reference direct-current voltage is the direct-current voltage output by the alternating-current power grid side converter station in a stable state of the flexible direct-current transmission system;
and S104, controlling the alternating voltage output by the oil-gas platform side converter station to be reduced according to the alternating voltage adjustment quantity.
In the present embodiment, in particular, in a flexible direct current transmission system for oil and gas platform power supply, the flexible direct current transmission system includes an alternating current grid side converter station and an oil and gas platform side converter station. The detection mode of the direct current voltage can include direct measurement or indirect measurement, wherein the direct measurement is generally a method of detecting the voltage through a series resistor, the indirect measurement is generally realized through detecting a magnetic field generated by current, and the magnitude of the measured current can be indirectly obtained through measuring the magnitude of the magnetic field due to the fact that the magnetic field is generated around the current. The direct measurement mainly refers to measurement by using a shunt, the shunt is constructed according to the principle that voltage is generated at two ends of a resistor when direct current is detected to pass through the resistor, the shunt can also be externally connected with an amplifying circuit to amplify signals, and then the signals are converted into digital signals through an A/D (analog/digital) conversion circuit. The indirect measurement is exemplified by a direct current transformer, which is a direct current sensor for indirect measurement constructed based on the magnetic modulation principle, and converts a large direct current passing through a coil into a small direct current in inverse turn ratio by a rectification circuit by utilizing nonlinearity and asymmetry when an iron core in an iron core coil is magnetized by direct current and alternating current together, and is mainly used for measuring the large direct current and also used as a current feedback, control and protection element in a rectification system.
When the AC power grid side has a fault, the AC voltage of the AC power grid rapidly drops, and the DC voltages of the corresponding AC power grid side converter station and the oil-gas platform side converter also rapidly drop. Judging whether the direct-current voltage of the oil-gas platform converter station is lower than a preset direct-current voltage threshold value or not; when the direct-current voltage is lower than the direct-current voltage threshold value, the fact that the alternating-current power grid side fails can be judged; and calculating an alternating current voltage adjustment amount, wherein the alternating current voltage adjustment amount is adapted to the variation of the direct current voltage relative to a reference direct current voltage, and the reference direct current voltage is the direct current voltage output by the alternating current network side converter station in the stable state of the flexible direct current transmission system. And controlling the alternating voltage output by the oil-gas platform side converter station to be reduced according to the alternating voltage adjustment quantity. Specifically, the ac voltage adjustment amount is calculated based on the amount of change in the dc voltage with respect to the reference dc voltage. For example, if the detected dc voltage is 1800V and the reference dc voltage is 2000V, the amount of change of the dc voltage with respect to the reference dc voltage is 200V, and if the detected dc voltage is 1600V, the amount of change of the dc voltage with respect to the reference dc voltage is 400V. The ac voltage adjustment amount is adapted to a variation of the dc voltage with respect to a reference dc voltage, that is, when the detected dc voltage is 1800V, the ac voltage adjustment amount should be calculated based on a variation of 200V, and when the detected dc voltage is 1600V, the ac voltage adjustment amount should be calculated based on a variation of 400V, and the ac voltage adjustment amount is adapted to the variation of the dc voltage with respect to the reference dc voltage, so as to accurately step down the ac voltage output by the converter station on the gas platform side, thereby ensuring power balance between the transmitting end and the receiving end, avoiding triggering dc voltage under-voltage protection, and ensuring fault ride-through of the entire flexible dc power transmission system.
In the above embodiment, specifically, whether a fault occurs on the ac power grid side is determined by detecting the dc voltage of the oil and gas platform converter station and determining whether the dc voltage is lower than a preset dc voltage threshold. And when the direct-current voltage is lower than the direct-current voltage threshold value, namely when the alternating-current power grid side is judged to have a fault, controlling the alternating-current voltage output by the oil-gas platform side converter station to be reduced by calculating the alternating-current voltage adjustment amount and controlling the alternating-current voltage according to the alternating-current voltage adjustment amount. The corresponding alternating-current voltage adjustment quantity is obtained through adaptive calculation of the direct-current voltage relative to the variable quantity of the reference direct-current voltage, so that the alternating-current voltage output by the oil-gas platform side converter station is accurately reduced, the problem that the direct-current voltage output by the alternating-current power grid side converter station is reduced due to the fact that the alternating-current power grid side responds to a fault is solved, the power balance of a sending end and a receiving end is guaranteed, direct-current voltage under-voltage protection is prevented from being triggered, the whole flexible direct-current power transmission system is prevented from being forced to stop running, the whole flexible direct-current power transmission system can smoothly perform fault ride-through, and the power transmission efficiency of the flexible direct-current power transmission system is improved. The fault ride-through method is easy to implement, has small delay compared with a mode of transmitting fault information by means of communication, and is independent of communication.
In an optional embodiment, specifically, in step S103, when the dc voltage is lower than the dc voltage threshold, calculating an ac voltage adjustment amount includes:
calculating a difference value between the direct current voltage and a reference direct current voltage based on a preset reference direct current voltage;
and converting by using the difference value to obtain the alternating voltage adjustment quantity.
Further, the ac voltage adjustment amount is calculated by the following formula:
△V＝KM(Vdcref-Vdc)
wherein Δ V represents an AC voltage adjustment amount, KMRepresents the gain factor, (V)dcref-Vdc) Representing the difference, V, between the reference DC voltage and the actual DC voltagedcrefRepresenting a reference DC voltage, VdcRepresenting the actual dc voltage.
In the above embodiment, specifically, if the dc voltage decreases, the ac voltage output by the converter station on the oil and gas platform side decreases, so as to limit the power drawn by the load (secondary load) of the oil and gas platform, thereby realizing power balance at the transmitting and receiving ends, maintaining the dc voltage within an acceptable range, continuing power transmission, and avoiding interruption of power transmission due to forced shutdown of the entire flexible dc power transmission system. By the formula Δ V ═ KM(Vdcref-Vdc) The method can accurately calculate the adjustment quantity of the alternating voltage, further improve the control efficiency of the alternating voltage output by the oil-gas platform side converter station, avoid the condition of blindly closing excessive loads for ensuring continuous power transmission, and further improve the power transmission efficiency of the flexible direct current power transmission system.
In one embodiment, specifically, the fault-ride-through method further includes:
and when the direct-current voltage is not lower than the direct-current voltage threshold value, controlling the oil-gas platform side converter station to output alternating-current voltage according to preset reference alternating-current voltage, wherein the reference alternating-current voltage is the alternating-current voltage output by the oil-gas platform side converter station in a stable state of the flexible direct-current transmission system.
In one embodiment, specifically, after controlling the alternating-current voltage output by the oil and gas platform side converter station to be stepped down according to the alternating-current voltage adjustment amount, the fault ride-through method further includes:
calculating a recovery adjustment amount;
and controlling the alternating voltage output by the oil-gas platform side converter station to be gradually boosted according to the recovery adjustment amount.
Further, the calculating the recovery adjustment amount includes:
detecting the current direct-current voltage of the oil-gas platform converter station again;
calculating a difference between the DC voltage and the current DC voltage based on the DC voltage and the current DC voltage;
and converting the difference value of the direct current voltage and the current direct current voltage to obtain the recovery adjustment quantity.
In the above-described embodiment, in particular, the troubleshooting on the ac power grid side requires a certain process. That is, when the fault on the ac power grid side is repaired to a corresponding degree, the repaired part will be put into use again, and therefore the power output by the repair part is required to be increased again by the receiving end on the oil and gas platform side, so as to improve the transmission efficiency of the flexible dc transmission system.
In the above embodiment, for example, the reference dc voltage is 2000V, the detected dc voltage is 1600V, after controlling the ac voltage output by the oil and gas platform side converter station to step down, the current dc voltage of the oil and gas platform side converter station is redetected to be 1800V, the calculated difference is 200V, the difference of 200V is converted into the corresponding recovery adjustment amount, and the ac voltage output by the oil and gas platform side converter station is gradually boosted according to the converted recovery adjustment amount.
Further, the alternating current voltage output by the oil and gas platform side converter station is controlled to be gradually boosted, the direct current voltage can be detected again, if the difference value is 1900V, the difference value of 300V is converted into a corresponding recovery adjustment amount, the alternating current voltage output by the oil and gas platform side converter station is controlled to be gradually boosted according to the recovery adjustment amount, and the boosted part should be considered in boosting at this time, so that repeated boosting is avoided.
Further, after the controlling the alternating-current voltage output by the oil and gas platform side converter station to be gradually boosted according to the recovery adjustment amount, the fault ride-through method further includes:
and after the fault is determined to be completely cleared, controlling the alternating-current voltage output by the oil-gas platform side converter station to be gradually boosted to the reference alternating-current voltage.
In the above embodiment, when the ac power grid side fails, the ac voltage output by the converter station on the oil and gas platform side is controlled to be reduced, so that power balance between the sending end and the receiving end is realized, triggering of dc voltage undervoltage protection is avoided, forced shutdown of the whole flexible dc power transmission system is avoided, smooth power transmission of the whole flexible dc power transmission system is realized, and power transmission efficiency of the flexible dc power transmission system is improved. In the fault repairing process, the alternating voltage output by the oil gas platform side converter station is boosted in time, and the operation reliability is further improved.
Example 2
Referring to fig. 5, an embodiment of the present invention further provides a fault ride-through device, which is used for a flexible direct-current power transmission system for supplying power to an oil and gas platform, where the flexible direct-current power transmission system includes an alternating-current power grid-side converter station, an oil and gas platform-side converter station, and a direct-current cable connecting the two converter stations, and the fault ride-through device includes:
the detection module 51 is used for detecting the direct-current voltage of the oil-gas platform converter station;
a determining module 52, configured to determine whether the dc voltage is lower than a preset dc voltage threshold;
a calculating module 53, configured to calculate an ac voltage adjustment amount when the dc voltage is lower than the dc voltage threshold, where the ac voltage adjustment amount is adapted to a variation amount of the dc voltage relative to a reference dc voltage, where the reference dc voltage is a dc voltage output by the ac power grid side converter station in a stable state of the flexible dc power transmission system;
and the control module 54 is used for controlling the alternating-current voltage output by the oil-gas platform side converter station to be reduced according to the alternating-current voltage adjustment amount.
The fault ride-through system provided by the embodiment of the invention can be used for the fault ride-through method in the above embodiment, and the implementation principle and the technical effect are similar as the related details refer to the above method embodiment, and are not described again here.
It should be noted that: in the fault ride-through device provided in the above embodiment, when performing fault ride-through, only the division of each functional module is illustrated, and in practical applications, the function distribution may be completed by different functional modules according to needs, that is, the internal structure of the fault ride-through device is divided into different functional modules to complete all or part of the functions described above. In addition, the fault ride-through system and the fault ride-through method provided by the above embodiments belong to the same concept, and specific implementation processes thereof are detailed in the above method embodiments and are not described herein again.
Example 3
The present embodiment provides a fault ride-through device, as shown in fig. 6, which includes a processor and a memory, where the processor and the memory may be connected by a bus or by other means, and fig. 6 illustrates the connection by the bus as an example.
The Processor may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), a Graphics Processing Unit (GPU), an embedded Neural Network Processor (NPU), other dedicated deep learning coprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), other Programmable logic device, a discrete device, a transistor logic device, a discrete hardware component, or the like, or a combination thereof.
The memory, which is a non-transitory computer readable storage medium, may be used to store non-transitory software programs, non-transitory computer executable programs, and modules, such as program instructions/modules corresponding to the fault ride-through method in embodiments of the present invention. The processor implements the fault-ride-through method of the above-described method embodiments by executing non-transitory software programs, instructions, and modules stored in the memory to thereby execute various functional applications and data processing of the processor.
The memory may include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function; the storage data area may store data created by the processor, and the like. Further, the memory may include high speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid state storage device. In some embodiments, the memory optionally includes memory located remotely from the processor, and such remote memory may be coupled to the processor via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof. The one or more modules are stored in the memory and, when executed by the processor, implement the fault-ride-through method of the above-described method embodiments.
Embodiments of the present invention further provide a non-transitory computer-readable storage medium, where computer-executable instructions are stored, where the computer-executable instructions may execute the fault ride-through method in any of the above method embodiments. The non-transitory computer readable storage medium may be a magnetic Disk, an optical Disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a Flash Memory (Flash Memory), a Hard Disk (Hard Disk Drive, abbreviated as HDD), a Solid-State Drive (SSD), or the like; the non-transitory computer readable storage medium may also include a combination of memories of the above kind.
It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, apparatus or non-transitory computer readable storage medium, all relating to or comprising a computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
Obviously, the above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that variations or modifications in other forms can be effected by a person skilled in the art on the basis of the foregoing description without departing from the spirit of the invention. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A fault ride-through method is used for a flexible direct current transmission system for supplying power to an oil and gas platform, the flexible direct current transmission system comprises an alternating current power grid side converter station, an oil and gas platform side converter station and a direct current cable for connecting the two converter stations, and the fault ride-through method is characterized by comprising the following steps of:
detecting the direct-current voltage of a converter station of the oil-gas platform;
judging whether the direct current voltage is lower than a preset direct current voltage threshold value or not;
when the direct-current voltage is lower than the direct-current voltage threshold value, calculating an alternating-current voltage adjustment quantity, wherein the alternating-current voltage adjustment quantity is adaptive to the variation of the direct-current voltage relative to a reference direct-current voltage, and the reference direct-current voltage is the direct-current voltage output by the alternating-current power grid side converter station in the stable state of the flexible direct-current transmission system;
and controlling the alternating voltage output by the oil-gas platform side converter station to be reduced according to the alternating voltage adjustment quantity.
2. The fault ride-through method of claim 1, wherein calculating an ac voltage adjustment when the dc voltage is below the dc voltage threshold comprises:
calculating a difference value between the direct current voltage and a reference direct current voltage based on a preset reference direct current voltage;
and converting by using the difference value to obtain the alternating voltage adjustment quantity.
3. The fault ride-through method of claim 2, wherein the ac voltage adjustment is calculated by the following equation:
△V＝KM(Vdcref-Vdc)
wherein Δ V represents an AC voltage adjustment amount, KMRepresents the gain factor, (V)dcref-Vdc) Representing the difference, V, between the reference DC voltage and the actual DC voltagedcrefRepresenting a reference DC voltage, VdcRepresenting the actual dc voltage.
4. The fault ride-through method of claim 3, further comprising:
and when the direct-current voltage is not lower than the direct-current voltage threshold value, controlling the oil-gas platform side converter station to output alternating-current voltage according to preset reference alternating-current voltage, wherein the reference alternating-current voltage is the alternating-current voltage output by the oil-gas platform side converter station in a stable state of the flexible direct-current transmission system.
5. The fault ride-through method according to claim 4, wherein after controlling the alternating voltage output by the oil and gas platform side converter station to be stepped down according to the alternating voltage adjustment amount, the method further comprises:
calculating a recovery adjustment amount;
and controlling the alternating voltage output by the oil-gas platform side converter station to be gradually boosted according to the recovery adjustment amount.
6. The fault ride-through method of claim 5, wherein the calculating the recovery adjustment comprises:
detecting the current direct-current voltage of the oil-gas platform converter station again;
calculating a difference between the DC voltage and the current DC voltage based on the DC voltage and the current DC voltage;
and converting the difference value of the direct current voltage and the current direct current voltage to obtain the recovery adjustment quantity.
7. The fault ride-through method according to claim 6, wherein after the step-by-step boosting of the alternating-current voltage output by the oil and gas platform side converter station according to the recovery adjustment amount is controlled, the method further comprises:
and after the fault is determined to be completely cleared, controlling the alternating-current voltage output by the oil-gas platform side converter station to be gradually boosted to the reference alternating-current voltage.
8. A fault ride-through device is used for a flexible direct current transmission system for supplying power to an oil and gas platform, the flexible direct current transmission system comprises an alternating current power grid side converter station, an oil and gas platform side converter station and a direct current cable for connecting the two converter stations, and the fault ride-through device is characterized by comprising:
the detection module is used for detecting the direct-current voltage of the oil-gas platform converter station;
the judging module is used for judging whether the direct current voltage is lower than a preset direct current voltage threshold value;
the calculation module is configured to calculate an ac voltage adjustment amount when the dc voltage is lower than the dc voltage threshold, where the ac voltage adjustment amount is adapted to a variation amount of the dc voltage with respect to a reference dc voltage, where the reference dc voltage is a dc voltage output by the ac power grid side converter station in a stable state of the flexible dc power transmission system;
and the control module is used for controlling the alternating-current voltage output by the oil-gas platform side converter station to be reduced according to the alternating-current voltage adjustment quantity.
9. A fault ride-through device, comprising: a memory and a processor communicatively coupled to each other, the memory having stored therein computer instructions, the processor executing the computer instructions to perform the fault ride-through method of any of claims 1-7.
10. A non-transitory computer readable storage medium storing computer instructions which, when executed by a processor, implement the fault ride-through method of any one of claims 1-7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111667691.7A CN114285067B (en) | 2021-12-31 | 2021-12-31 | Fault ride-through method and device and storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111667691.7A CN114285067B (en) | 2021-12-31 | 2021-12-31 | Fault ride-through method and device and storage medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114285067A true CN114285067A (en) | 2022-04-05 |
| CN114285067B CN114285067B (en) | 2024-01-16 |
Family
ID=80879552
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111667691.7A Active CN114285067B (en) | 2021-12-31 | 2021-12-31 | Fault ride-through method and device and storage medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114285067B (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106451401B (en) * | 2016-05-16 | 2019-02-05 | 浙江大学 | The control method of inverter maximum power output when DC voltage falls |
| CN106451516B (en) * | 2016-08-27 | 2020-04-10 | 许继集团有限公司 | Direct-current fault ride-through method of hybrid multi-terminal high-voltage direct-current transmission system |
| CN112018801B (en) * | 2020-08-06 | 2022-01-21 | 江苏省电力试验研究院有限公司 | Receiving-end cascade hybrid direct current coordination control method based on dynamic amplitude limiting |
| CN112421669B (en) * | 2020-12-10 | 2021-10-22 | 南方电网科学研究院有限责任公司 | Alternating current fault ride-through method and system for offshore wind power through flexible direct current transmission |
-
2021
- 2021-12-31 CN CN202111667691.7A patent/CN114285067B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114285067B (en) | 2024-01-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110233490B (en) | Direct-current transmission fault recovery control method and system for avoiding continuous commutation failure | |
| EP3796507A1 (en) | Direct-current bus voltage reference value adjustment method and apparatus, and photovoltaic grid-connected inverter | |
| CN103986339B (en) | Power conversion system, voltage modulation device and its method | |
| JP4306760B2 (en) | Distributed power supply | |
| CN103972900B (en) | Utilize the method that voltage control sensitive factor determination Multi-infeed HVDC transmission system reactive power compensator is layouted | |
| EP3681006A1 (en) | Voltage and current control method and device for direct-current power transmission system | |
| CN107482668B (en) | High-voltage direct-current constant-reactive power alternating-current fault recovery method and device | |
| CN106950512B (en) | Energy storage converter grid-connected and grid-disconnected characteristic integrated detection system and method | |
| CN104242331A (en) | Extra-high voltage direct current control system suitable for electromechanical transient simulation | |
| CN103311957A (en) | Control method and control system for grid-side converter | |
| CN103904678B (en) | The control method of high voltage direct current transmission Shift speed segmentally rate current limiting low-voltage unit | |
| CN105633997A (en) | Wind generating set voltage crossing control method and device | |
| CN105633998A (en) | Wind generating set high-voltage crossing control method and device | |
| CN105633999A (en) | High-voltage crossing control method and device under imbalanced sudden rise of power grid voltage | |
| CN104811025A (en) | Auxiliary converter with multiple protections | |
| CN104734172A (en) | Self-adaption PI control method for improving HVDC system suppressing phase commutation failure capacity | |
| CN104167939B (en) | Method and device for modulating current transformer | |
| CN114285067A (en) | Fault ride-through method, device and storage medium | |
| CN103904679B (en) | The control method of high voltage direct current transmission discrete constant current command type current limiting low-voltage unit | |
| CN110289639B (en) | Cascading converter and control method and application system thereof | |
| CN114614487A (en) | Voltage safety domain evaluation method for high-voltage direct-current transmission system | |
| Hiremath et al. | Transient analysis of LCC based HVDC offshore wind farms using DIgSILENT PowerFactory | |
| CN110323776B (en) | SC-based L CC-HVDC receiving end direct current system feedforward control method, system and medium | |
| Zidi et al. | Regular paper Dynamic Performance of an HVDC Link | |
| KR101342435B1 (en) | Vdcol unit of high voltage dc system and method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |