A kind of mixed DC closed loop test system and implementation method
Technical field
Patent of the present invention relates to HVDC Transmission Technology and closed test thereof, particularly closed loop test system and its implementation of a kind of sending end to be customary DC receiving end be mixed DC of flexible direct current.
Background technology
In customary DC power transmission engineering, extensively adopt line commutation transverter (the Line-Communicated Converter based on thyristor at present, LCC), be specially adapted to Large Copacity high voltage and transmit electricity at a distance occasion, but the problem of commutation failure is existed for receiving end weak pattern system.In recent years along with the development of the new forms of energy such as wind-power electricity generation, Technology of HVDC based Voltage Source Converter is got more and more the concern of experts and scholars and engineer applied both at home and abroad.Flexible direct current adopts modularization multi-level converter (the Voltage Source Converter based on full control devices such as IGBT, VSC), control is more flexible compared with customary DC, the four-quadrant realizing power controls, particularly there is not commutation problem, be applicable to new forms of energy access electrical network and the occasion such as power to passive network.
The relative merits of comprehensive customary DC and flexible direct current, a kind of mixed DC adopting sending end to be customary DC receiving end to be flexible direct current, can be used for overcoming customary DC exists commutation failure problem to receiving end weak pattern system.The invention provides the implementation method that a kind of receiving end is the mixed DC closed loop test system of flexible direct current, for the research of mixed DC Control protection characteristic and closed test thereof provide effective test method, simple, convenient.
Summary of the invention
A kind of receiving end is the object of the present invention is to provide to be mixed DC closed loop test system and the implementation method of flexible direct current; for solving the protection feature research of mixed DC Systematical control and closed test thereof that receiving end is flexible direct current, for the Control protection characteristic studying the mixed DC system that receiving end is flexible direct current provides effective test platform and method.
Above-mentioned purpose of the present invention is realized by following technological means:
The invention provides the mixed DC closed loop test system that a kind of receiving end is flexible direct current, include the closed loop test system set up and be made up of the LCC valve control device of the MMC simulator of the Real Time Digital Simulator of simulation mixed DC system, real-time simulation workstation, analog module multilevel converter, MMC valve control device, MMC unit control protection device, IO board, photoelectric conversion device, customary DC, LCC unit control protection device and mixed DC system coordination control device.
The described mixed DC system simulated in real-time simulator includes AC system, alternating current filter, ac bus, AC circuit breaker, customary DC unit, flexible direct current unit and large step-length interface circuit and little step-length interface circuit;
Described alternating current filter is parallel to the ac bus of customary DC side, the DC side of described customary DC unit and flexible direct current unit respectively by 50us large step-length interface circuit and 2.5us little step-length interface circuit interconnected, AC is connected on described ac bus by AC circuit breaker;
Described customary DC includes three-phase three winding converter power transformer, 12 pulse conversion device LCC and direct current reactors based on thyristor; Described three-phase three winding converter power transformer is connected with ac bus by AC circuit breaker; The DC side of described 12 pulse conversion devices is connected with large step-length interface circuit by direct current reactor; The AC of described 12 pulse conversion devices by two 6 pulse conversion units respectively with Y winding and the D winding switching of three-phase three-winding transformer secondary side; Described 6 pulse conversion units are made up of three thyristor groups parallel connections, and each thyristor groups is made up of two thyristors of connecting, and the tie point of two 6 pulse conversion circuit is parallel with grounding switch;
Described flexible direct current includes modularization multi-level converter MMC, three-phase double winding tietransformer, by-pass switch and starting resistance; The primary side of described three-phase double winding tietransformer is connected to described AC circuit breaker, and secondary side is connected to described starting resistance; Described by-pass switch is parallel to starting resistance, and the other end of described starting resistance is connected to the AC of modularization multi-level converter.The DC side of described modularization multi-level converter by little step-length interface circuit and large step-length interface circuit interconnected.Modularization multi-level converter is made up of three-phase six brachium pontis, and each brachium pontis is made up of a brachium pontis reactor and multiple submodule;
Described submodule comprises an IGBT pipe respectively, the 2nd IGBT manages, manage antiparallel first diode with an IGBT, manage antiparallel second diode with the 2nd IGBT and capacitor is formed; The collector of a described IGBT pipe is connected with the emitter of the 2nd IGBT pipe, and described capacitor one end is connected with the emitter of an IGBT pipe, and the described capacitor other end is connected with the collector of the 2nd IGBT pipe.
Real-time simulation workstation is crossed netting twine with the PB5 disposable plates cartoon of Real Time Digital Simulator and is connected, for calculating the electrical network of mixed DC system; The PB5 board of Real Time Digital Simulator is adopted to simulate the little step-length emulation of 2.5us of flexible direct current respectively, and the large step-length emulation of the 50us of customary DC and other circuit.Described two pieces of PB5 boards by the backboard communication of Real Time Digital Simulator, and use Fiber connection.
PB5 board in described Real Time Digital Simulator is connected with IO board by optical fiber, for realizing the input and output of analog quantity and digital quantity signal; PB5 board is connected with modularization multi-level converter MMC simulator, for MMC model emulation by optical fiber; MMC simulator is connected with MMC valve control device by optical fiber, controls for the submodule switching realizing MMC; MMC valve control device is connected with MMC unit control protection device with cable, for realizing the control objectives of flexible direct current by optical fiber; MMC unit control protection device is connected with IO board by cable, for analog quantity and digital quantity signal mutual.
Described IO board is connected with photoelectric conversion device by cable, and the electric signal that IO board exports is changed into light signal by photoelectric conversion device, then is connected with the LCC valve control device of customary DC, for realizing the trigging control of 12 pulse conversion devices by optical fiber; LCC valve control device is connected with LCC unit control protection device with cable, for realizing the control objectives of customary DC by optical fiber; LCC unit control protection device is connected with IO board by cable, for analog quantity and digital quantity signal mutual;
Described MMC unit control protection device is connected with mixed DC system coordination control device by optical fiber and cable with LCC unit control protection device, controls for the mixed DC system coordination realizing sending end customary DC and receiving end flexible direct current.
The present invention provides the implementation method of this mixed DC closed loop test system simultaneously, comprises the steps:
Step 1, sets up the mixed DC system Real-Time Model that sending end is customary DC, receiving end is flexible direct current in real-time simulation workstation;
Step 2, to be linked the PB5 disposable plates of real-time simulation workstation and Real Time Digital Simulator by netting twine and connects, for calculating the electrical network of mixed DC system;
Step 3, is connected with MMC simulator by the PB5 process board of optical fiber by Real Time Digital Simulator.The valve group parameters such as valve group submodule number, brachium pontis reactance value, submodule capacitance are passed to MMC simulator by Real Time Digital Simulator PB5 process board, and the valve group states such as submodule running status, brachium pontis total voltage, submodule capacitor voltage are back to Real Time Digital Simulator PB5 process board by MMC simulator;
Step 4, MMC simulator is connected with MMC valve control device by optical fiber, controls for the submodule switching realizing MMC; Submodule capacitor voltage, bridge arm current are given MMC valve control device by international AURORA agreement by MMC simulator, and submodule trigger pulse is given MMC simulator by AURORA agreement by MMC valve control device;
Step 5, the PB5 disposable plates cartoon in Real Time Digital Simulator is crossed optical fiber and is connected with IO board, for realizing the input and output of analog quantity and digital quantity signal; MMC valve control device is connected with MMC unit control protection device with cable, for realizing the control objectives of flexible direct current by optical fiber; MMC unit control protection device is connected with IO board by cable, for analog quantity and digital quantity signal mutual;
Step 6, IO board is connected with photoelectric conversion device by cable, and the electric signal that IO board exports is changed into light signal by photoelectric conversion device, then is connected with the LCC valve control device of customary DC, for realizing the trigging control of 12 pulse conversion devices by optical fiber; LCC valve control device is connected with LCC unit control protection device with cable, for realizing the control objectives of customary DC by optical fiber; LCC unit control protection device is connected with IO board by cable, for analog quantity and digital quantity signal mutual;
Step 7, described MMC unit control protection device is connected with mixed DC system coordination control device by optical fiber and cable with LCC unit control protection device, controls for the mixed DC system coordination realizing sending end customary DC and receiving end flexible direct current.
Receiving end provided by the invention is mixed DC closed loop test system and the implementation method of flexible direct current; it is the mixed DC Systematical control protection feature research of flexible direct current and the closed loop test of device thereof that the closed loop test system set up can be used for receiving end; simple to operate, convenient and practical.
Accompanying drawing explanation
The present invention is further illustrated to utilize accompanying drawing.
The schematic diagram of Fig. 1 to be a kind of receiving end of the present invention be mixed DC closed loop test system of flexible direct current;
Fig. 2 is that in the present invention, a kind of receiving end is the mixed DC system construction drawing of flexible direct current;
Fig. 3 is the topology diagram of customary DC 12 pulse conversion device;
Fig. 4 is the topology diagram of flexible direct current MMC transverter;
Fig. 5 is the topology diagram of MMC transverter Neutron module;
In Fig. 1 to Fig. 5, comprising:
Real Time Digital Simulator (1), real-time simulation workstation (2), PB5 board (3), MMC simulator (4), MMC valve control device (5), MMC unit control protection device (6), IO board (7), photoelectric conversion device (8), LCC valve control device (9), LCC unit control protection device (10), mixed DC system coordination control device (11);
AC system (12), alternating current filter (13), ac bus (14), exchange main circuit breaker (15),
Customary DC unit (16), three-phase three winding converter power transformer (161), 12 pulse conversion units (162), reactor (163), large step-length interface circuit (17), little step-length interface circuit (18);
Flexible direct current unit (19), modularization multi-level converter (191), by-pass switch (192), starting resistance (193), three-phase double winding tietransformer (194);
6 pulse conversion devices (20), thyristor (21), grounding switch (22);
Multi-level inverter bridge arm (23), brachium pontis reactor (24), submodule (25);
IGBT pipe (26), anti-also diode (27), capacitor (28).
Embodiment
The invention will be further described with the following Examples.
Embodiment;
The present invention carry a kind of receiving end be the mixed DC closed loop test system of flexible direct current as shown in Figure 1, include Real Time Digital Simulator (1), real-time simulation workstation (2), PB5 board (3), MMC simulator (4), MMC valve control device (5), MMC unit control protection device (6), IO board (7), photoelectric conversion device (8), LCC valve control device (9), LCC unit control protection device (10), mixed DC system coordination control device (11).
The implementation method of a kind of sending end to be customary DC receiving end be mixed DC closed loop test system of flexible direct current comprises the steps:
1) sending end set up in real-time simulation workstation is as shown in Figure 2 customary DC, receiving end is the mixed DC system Real-Time Model of flexible direct current;
2) by netting twine, real-time simulation workstation (2) is connected with the PB5 process board (3) of Real Time Digital Simulator (1), for calculating the electrical network of mixed DC system;
3) be connected (4) with MMC simulator by the PB5 process board (3) of optical fiber by Real Time Digital Simulator.The valve group parameters such as valve group submodule number, brachium pontis reactance value, submodule capacitance are passed to MMC simulator (4) by Real Time Digital Simulator PB5 process board (3), and the valve group states such as submodule running status, brachium pontis total voltage, submodule capacitor voltage are back to Real Time Digital Simulator PB5 process board (3) by MMC simulator (4);
4) MMC simulator (4) is connected with MMC valve control device (5) by optical fiber, controls for the submodule switching realizing MMC; Submodule capacitor voltage, bridge arm current are given MMC valve control device (5) by international AURORA agreement by MMC simulator (4), and submodule trigger pulse is given MMC simulator (4) by AURORA agreement by MMC valve control device (5);
5) the PB5 process board (3) in Real Time Digital Simulator is connected with IO board (7) by optical fiber, for realizing the input and output of analog quantity and digital quantity signal; MMC valve control device (5) is connected with MMC unit control protection device (6) with cable by optical fiber, for realizing the control objectives of flexible direct current; MMC unit control protection device (6) is connected with IO board (7) by cable, for analog quantity and digital quantity signal mutual;
6) IO board (7) is connected with photoelectric conversion device (8) by cable, the electric signal that IO board (7) exports is changed into light signal by photoelectric conversion device (8), be connected with LCC valve control device (9) of customary DC by optical fiber again, for realizing the trigging control of 12 pulse conversion devices; LCC valve control device (9) is connected with LCC unit control protection device (10) with cable by optical fiber, for realizing the control objectives of customary DC; LCC unit control protection device (10) is connected with IO board (7) by cable, for analog quantity and digital quantity signal mutual;
7) described MMC unit control protection device (6) is connected with mixed DC system coordination control device (11) by optical fiber and cable with LCC unit control protection device (10), controls for the mixed DC system coordination realizing sending end customary DC and receiving end flexible direct current.
The invention provides a kind of closed loop test system for sending end to be customary DC receiving end the be mixed DC of flexible direct current, simple to operate, convenient and practical.For the Control protection characteristic that research receiving end is the mixed DC system of flexible direct current, provide effective closed loop test platform.
Finally should be noted that; above embodiment is only in order to illustrate technical scheme of the present invention but not limiting the scope of the invention; although be explained in detail the present invention with reference to preferred embodiment; those of ordinary skill in the art is to be understood that; can modify to technical scheme of the present invention or equivalent replacement, and not depart from essence and the scope of technical solution of the present invention.