CN109412178B - Switching control method of high-voltage high-capacity impedance measurement equipment - Google Patents
Switching control method of high-voltage high-capacity impedance measurement equipment Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/025—Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/76—Power conversion electric or electronic aspects
Abstract
The invention discloses a switching control method of high-voltage high-capacity impedance measurement equipment. The output of the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into a high-voltage line of the new energy power generation equipment to be tested through a coupling transformer, and a voltage disturbance source is provided. The input and the removal of the high-voltage large-capacity broadband voltage disturbance injection device are directly related to the safe and stable operation of the equipment to be tested, the voltage disturbance injection device and the power grid. A soft switching control method is provided for a high-voltage high-capacity broadband voltage disturbance injection device of the high-voltage high-capacity impedance measurement device, and impact on equipment to be tested, the voltage disturbance injection device and a power grid cannot be caused in the switching process of the high-voltage high-capacity broadband voltage disturbance injection device. The method can provide technical support for the on-line measurement of the broadband output impedance in high-voltage and high-capacity scenes such as wind power generation.
Description
Technical Field
The invention relates to the technical field of impedance online measurement in new energy power generation, in particular to a switching control method of high-voltage high-capacity impedance measurement equipment.
Background
The rapid development of renewable energy is an important measure for guaranteeing energy safety and coping with climate change in China, wind power generation and photovoltaic power generation are main ways for utilizing renewable energy in China, and the construction of ten million kilowatt-level wind power/photovoltaic bases in the three North China and the utilization of extra-high voltage direct current (UHVDC) transmission are the leading forms for developing and utilizing renewable energy in China at present. In a direct current delivery system of a renewable energy power generation base, the number of power electronic power generation equipment is large, the control is complex, multi-time scale coupling exists, dynamic interaction between bases and between the bases and direct current transmission is intensified, so that a broadband oscillation mechanism is unclear, and modeling and analysis face great challenges.
An impedance method in a frequency domain theory is one of the most common methods for analyzing the oscillation problem of a grid-connected system of a new energy converter, and the basic idea is to consider the converter and an alternating current power grid as two independent subsystems, describe the external characteristics of the subsystems by using an impedance matrix, and judge the stability of the system by using the impedance ratio of the subsystems. Compared with a eigenvalue analysis method based on a state space model, the impedance method does not depend on detailed models and specific parameters of the system, the required impedance matrix can be obtained by measuring the external port characteristics of the actual system, the system scale can be expanded by an impedance aggregation method, and the method is particularly suitable for analysis of a large-scale system consisting of a large number of heterogeneous new energy units and is widely applied. The research and development of the broadband impedance characteristic measurement technology and equipment of the new energy power generation equipment are the basis and the key of the application of an impedance method, and are effective means for solving the problems that the impedance characteristic of the new energy power generation equipment is difficult to accurately measure, and the existing simulation tool cannot adapt to the huge number of new energy units. Therefore, the research on the broadband impedance characteristic measurement technology and equipment has great significance in disclosing the broadband oscillation mechanism of the direct current delivery system of the new energy power generation base and providing an oscillation defense and inhibition method.
However, currently, the research on impedance measurement equipment is mainly focused on the low-voltage small-capacity field, the research on impedance measurement equipment with high voltage and large capacity is still in the initial stage, and the research is not complete. Therefore, the invention provides a switching control method of the high-voltage large-capacity impedance measuring equipment, which can not cause impact on equipment to be tested, the voltage disturbance injection device and a power grid in the switching process of the high-voltage large-capacity broadband voltage disturbance injection device in the high-voltage large-capacity impedance measuring equipment. The method can provide technical support for the on-line measurement of the broadband output impedance in high-voltage and high-capacity scenes such as wind power generation.
Disclosure of Invention
The invention aims to solve the technical problem that the switching control method of the high-voltage high-capacity impedance measuring equipment is provided aiming at the defects of the prior art, and can meet the requirement of on-line measurement of broadband output impedance in high-voltage high-capacity scenes such as wind power generation and the like.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a switching control method of high-voltage large-capacity impedance measurement equipment is characterized in that the high-voltage large-capacity impedance measurement equipment mainly comprises a high-voltage large-capacity broadband voltage disturbance injection device, a signal processing unit, a broadband impedance calculation and monitoring unit and a control unit. The input of the high-voltage large-capacity broadband voltage disturbance injection device is connected to a high-voltage power grid in parallel through a normally-open switch S1; the output of the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into a high-voltage line of the new energy power generation equipment to be tested through a normally-open switch S2 to provide a voltage disturbance source, and the normally-closed switch S3 serves as a bypass switch of the output of the high-voltage high-capacity broadband voltage disturbance injection device.
A switching control method of high-voltage large-capacity impedance measurement equipment is characterized in that a high-voltage large-capacity broadband voltage disturbance injection device in the high-voltage large-capacity impedance measurement equipment is mainly used for being operated and comprises the following steps:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is put into use, S1 and S2 are in an open state, S3 is in a closed state, and the new energy power generation equipment to be tested normally generates power;
2) s1 is closed, three-phase uncontrollable rectification of the high-voltage large-capacity broadband voltage disturbance injection device is pre-charged, after the voltage of the direct current side is stabilized, the inversion part of the high-voltage large-capacity broadband voltage disturbance injection device starts no-load self-detection, the inversion modulation wave is set to be 0 after the self-detection is completed, and the output voltage of the inversion part is expected to be 0;
3) then S2 is closed, the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into the circuit, and the output voltage of the device is 0 at the moment, so that large impact cannot be generated;
4) and finally, S3 is cut off, all output currents of the new energy power generation equipment to be measured flow through the high-voltage high-capacity broadband voltage disturbance injection device, the high-voltage high-capacity broadband voltage disturbance injection device can emit expected voltage waveforms after the system is stabilized, and the high-voltage high-capacity impedance measurement equipment can start to perform broadband impedance online measurement.
A switching control method of high-voltage large-capacity impedance measurement equipment is characterized in that a high-voltage large-capacity broadband voltage disturbance injection device in the high-voltage large-capacity impedance measurement equipment mainly comprises the following steps during the operation of cutting off:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is cut off, S1 and S2 are in a closed state, and S3 is in an open state;
2) setting an inversion modulation wave of the high-voltage large-capacity broadband voltage disturbance injection device to be 0, and expecting the output voltage of an inversion part to be 0;
3) s3 is closed, S2 is opened after the system is stabilized, and the high-voltage high-capacity broadband voltage disturbance injection device is cut off from the line;
4) and (3) stopping the operation of all the IGBTs of the high-voltage high-capacity broadband voltage disturbance injection device, then disconnecting S1, cutting off the device, and enabling the new energy power generation equipment to be tested to generate power uninterruptedly in the whole switching process.
Compared with the prior art, the invention has the beneficial effects that: the invention provides a switching control method of high-voltage high-capacity impedance measurement equipment, which can not cause impact on equipment to be tested, a voltage disturbance injection device and a power grid in the switching process of a high-voltage high-capacity broadband voltage disturbance injection device in the high-voltage high-capacity impedance measurement equipment.
Drawings
FIG. 1 is a system structure diagram of a high-voltage large-capacity impedance measurement device according to an embodiment of the present invention;
fig. 2 is a switching control method of the high-voltage large-capacity impedance measurement device according to an embodiment of the present invention;
fig. 3 is a simulation waveform of switching control of the high-voltage large-capacity impedance measurement device according to an embodiment of the present invention.
Detailed Description
As shown in fig. 1, a switching control method for a high-voltage large-capacity impedance measurement device is characterized in that the high-voltage large-capacity impedance measurement device mainly comprises a high-voltage large-capacity broadband voltage disturbance injection device, a signal processing unit, a broadband impedance calculation and monitoring unit and a control unit. The input of the high-voltage large-capacity broadband voltage disturbance injection device is connected to a high-voltage power grid in parallel through a normally-open switch S1; the output of the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into a high-voltage line of the new energy power generation equipment to be tested through a normally-open switch S2 to provide a voltage disturbance source, and the normally-closed switch S3 serves as a bypass switch of the output of the high-voltage high-capacity broadband voltage disturbance injection device.
As shown in fig. 2, a switching control method for a high-voltage high-capacity impedance measurement device is characterized in that a high-voltage high-capacity broadband voltage disturbance injection device in the high-voltage high-capacity impedance measurement device mainly comprises the following steps:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is put into use, S1 and S2 are in an open state, S3 is in a closed state, and the new energy power generation equipment to be tested normally generates power;
2) s1 is closed, three-phase uncontrollable rectification of the high-voltage large-capacity broadband voltage disturbance injection device is pre-charged, after the voltage of the direct current side is stabilized, the inversion part of the high-voltage large-capacity broadband voltage disturbance injection device starts no-load self-detection, the inversion modulation wave is set to be 0 after the self-detection is completed, and the output voltage of the inversion part is expected to be 0;
3) then S2 is closed, the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into the circuit, and the output voltage of the device is 0 at the moment, so that large impact cannot be generated;
4) and finally, S3 is cut off, all output currents of the new energy power generation equipment to be measured flow through the high-voltage high-capacity broadband voltage disturbance injection device, the high-voltage high-capacity broadband voltage disturbance injection device can emit expected voltage waveforms after the system is stabilized, and the high-voltage high-capacity impedance measurement equipment can start to perform broadband impedance online measurement.
As shown in fig. 2, a switching control method for a high-voltage high-capacity impedance measurement device is characterized in that a high-voltage high-capacity broadband voltage disturbance injection device in the high-voltage high-capacity impedance measurement device mainly comprises the following steps during the operation of cutting off:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is cut off, S1 and S2 are in a closed state, and S3 is in an open state;
2) setting an inversion modulation wave of the high-voltage large-capacity broadband voltage disturbance injection device to be 0, and expecting the output voltage of an inversion part to be 0;
3) s3 is closed, S2 is opened after the system is stabilized, and the high-voltage high-capacity broadband voltage disturbance injection device is cut off from the line;
4) and (3) stopping the operation of all the IGBTs of the high-voltage high-capacity broadband voltage disturbance injection device, then disconnecting S1, cutting off the device, and enabling the new energy power generation equipment to be tested to generate power uninterruptedly in the whole switching process.
As shown in FIG. 3, ea、eb、ecThree-phase output voltage v of high-voltage large-capacity broadband voltage disturbance injection devicepLa、vpLb、vpLcThree-phase input voltage i of new energy power generation equipment to be testedpa、ipb、ipcFor the three-phase input current of the new energy power generation equipment to be tested, the simulation waveform shows that no large impact occurs in the whole switching process of the high-voltage large-capacity broadband voltage disturbance injection device.
Claims (1)
1. The input of a high-voltage high-capacity broadband voltage disturbance injection device is connected in parallel to a high-voltage power grid through a normally open switch S1; the output of the high-voltage high-capacity broadband voltage disturbance injection device is connected in series into a high-voltage line of the new energy power generation equipment to be tested through a normally open switch S2 to provide a voltage disturbance source, and the normally closed switch S3 is used as a bypass switch for the output of the high-voltage high-capacity broadband voltage disturbance injection device; the method is characterized in that the switching control method of the high-voltage large-capacity impedance measurement equipment comprises the switching operation control and the cutting operation control of the high-voltage large-capacity broadband voltage disturbance injection device; the high-voltage large-capacity broadband voltage disturbance injection device in the high-voltage large-capacity impedance measurement equipment comprises the following steps of:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is put into use, S1 and S2 are in an open state, S3 is in a closed state, and the new energy power generation equipment to be tested normally generates power;
2) s1 is closed, three-phase uncontrollable rectification of the high-voltage large-capacity broadband voltage disturbance injection device is pre-charged, after the voltage of the direct current side is stabilized, the inversion part of the high-voltage large-capacity broadband voltage disturbance injection device starts no-load self-detection, the inversion modulation wave is set to be 0 after the self-detection is completed, and the output voltage of the inversion part is expected to be 0;
3) s2 is closed, and the high-voltage high-capacity broadband voltage disturbance injection device is connected in series to the line;
4) s3 is cut off, all output currents of the new energy power generation equipment to be tested flow through the high-voltage large-capacity broadband voltage disturbance injection device, the high-voltage large-capacity broadband voltage disturbance injection device sends expected voltage waveforms after the system is stabilized, and the high-voltage large-capacity impedance measurement equipment starts to perform broadband impedance online measurement;
the operation of the high-voltage large-capacity broadband voltage disturbance injection device in the high-voltage large-capacity impedance measurement equipment comprises the following steps:
1) before the high-voltage large-capacity broadband voltage disturbance injection device is cut off, S1 and S2 are in a closed state, and S3 is in an open state;
2) setting an inversion modulation wave of the high-voltage large-capacity broadband voltage disturbance injection device to be 0, and expecting the output voltage of an inversion part to be 0;
3) s3 is closed, S2 is opened after the system is stabilized, and the high-voltage high-capacity broadband voltage disturbance injection device is cut off from the line;
4) and (4) stopping the operation of all the IGBTs of the high-voltage large-capacity broadband voltage disturbance injection device, then disconnecting S1, cutting off the device, and generating power uninterruptedly by the new energy power generation equipment to be tested in the whole switching process.
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| CN110850175B (en) * | 2019-11-19 | 2022-03-04 | 大连海事大学 | Direct current micro-grid line impedance detection method and device based on low-frequency current injection |
| CN112881822B (en) * | 2021-01-07 | 2023-06-02 | 国网河北省电力有限公司电力科学研究院 | Detection method and equipment for voltage control function of wind farm |
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