CN104779612A - Multi-PCC (point of common coupling) controlled micro-grid system control method based on PCS (power convert system) energy storing devices - Google Patents
Multi-PCC (point of common coupling) controlled micro-grid system control method based on PCS (power convert system) energy storing devices Download PDFInfo
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Abstract
The invention relates to a multi-PCC (point of common coupling) controlled micro-grid system control method based on PCS (power convert system) energy storing devices. According to the control method, a first PCC switching point and a second PCC switching point are arranged at connected points of a micro-grid system and a large grid system, a third PCC switching point is arranged on an inner common bus of the micro-grid system, the micro-grid system is controlled through controlling of the PCC switching points, and multiple PCS energy storing devices are connected onto the inner common bus. The control method comprises specific steps as follows: a), a step of electrical breakdown control; b), a step of grid power restoration control. Compared with the prior art, the first PCC switching point and the second PCC switching point are arranged at the connected points of the micro-grid system and the large grid system, and the third PCC switching point is arranged on the inner common bus of the micro-grid system, so that the control strategy of the micro-grid system for the PCS energy storing devices is realized through controlling of the three PCC switching points, and the method has the advantages of flexibility and convenience in control and the like.
Description
Technical field
The present invention relates to electric and electronic technical field, especially relate to a kind of micro-grid system control method of many PCC point control of Based PC S energy storage device.
Background technology
At present, in large-scale micro-grid system (as island microgrid system etc.) application, the rated capacity of separate unit PCS energy storage device cannot meet so huge generating and using electricity system, for ensureing the stability that large-scale micro-grid system runs, give full play to the coordinative role of PCS (Power Convert System) energy storage device to generate electricity end and load end, general employing multiple pc S energy storage device cooperation, makes up the problem that rated capacity cannot meet.
Chinese patent application CN 104218612A discloses the flexible grid-connected control method of a kind of micro-capacitance sensor based on points of common connection place overall-in-one control schema, at PCC place configuration energy-storage system and SSTS, the complete micro-capacitance sensor utilizing micro-capacitance sensor and power distribution network points of common connection place to collect and power distribution network information about power, coordinate the energy storage that this place configures, send idle to power distribution network when generation falls in distribution network voltage temporarily, consume unnecessary idle during voltage swell, alleviate Voltage Instability degree; Coordinate solid converting switch, improve micro-capacitance sensor from net switch speed and precision.But along with the increase gradually of power system capacity, single PCC point (Point of Common Coupling, points of common connection) control the connection of whole system and electrical network mode too single, cause the control strategy of internal system cannot realize the use of P/Q (being incorporated into the power networks) to multiple pc S energy storage device, V/F (islet operation) control model flexibly.
So need the micro-capacitance sensor network architecture of the multiple PCC points designing a kind of Based PC S energy storage device, to meet the flexible use of Large Copacity micro-grid system control strategy.
Summary of the invention
Object of the present invention be exactly in order to overcome above-mentioned prior art exist defect and a kind of micro-grid system control method controlling many PCC point control of flexible Based PC S energy storage device is provided.
Object of the present invention can be achieved through the following technical solutions:
A kind of micro-grid system control method of many PCC point control of Based PC S energy storage device, this control method arranges a PCC switching point and the 2nd PCC switching point at micro-grid system and bulk power system tie point place, the inside common bus of micro-grid system arranges the 3rd PCC switching point, by controlling the control realization micro-grid system of each PCC switching point, described inner common bus is connected with multiple pc S energy storage device, this control method specifically comprises:
A) electrical breakdown rate-determining steps;
B) power system restoration power supply control step.
Described electrical breakdown rate-determining steps is specially:
A01) detect whether there is the instruction of plan isolated island, if so, then enter plan isolated island control strategy, perform step a02), if not, then enter unplanned isolated island control strategy;
A02) judge whether the 3rd PCC switching point closes, if so, then perform step a03), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, perform step a06);
A03) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a04), if not, then perform step a05);
A04) mark a PCS energy storage device and enter V/F pattern, disconnect the 2nd PCC switching point and a PCC switching point successively, the PCS energy storage device to mark sends and turns V/F instruction;
A05) disconnect the 2nd PCC switching point and a PCC switching point successively, send to all PCS energy storage devices simultaneously and turn V/F instruction;
A06) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a07), if not, then perform step a08);
A07) the PCS energy storage device marking two micro-capacitance sensor subsystems respectively enters V/F pattern, disconnects a PCC switching point and the 2nd PCC switching point simultaneously, and the PCS energy storage device to two station symbol notes sends and turns V/F instruction;
A08) disconnect a PCC switching point and the 2nd PCC switching point simultaneously, send to all PCS energy storage devices and turn V/F instruction.
In described unplanned isolated island control strategy, the 2nd PCC switching point and a PCC switching point are and disconnect simultaneously.
Described power system restoration power supply control step is specially:
B01) judge whether the 3rd PCC switching point closes, if so, then perform step b02), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, perform step b06);
B02) judge whether PCS energy storage device is in unit V/F pattern, if so, then the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern, perform step b03), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b03);
B03) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and microgrid side be all consistent, if so, then stop regulate the same period, perform step b05), if not, then perform step b04);
B04) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b03);
B05) a closed PCC switching point, and the instruction turning P/Q pattern is sent to PCS energy storage device, judge whether all PCS energy storage devices normally run, if so, then close a PCC switching point, if not, then return step b05);
B06) judge whether PCS energy storage device is in unit V/F pattern, if, then respectively the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern in two micro-capacitance sensor subsystems, perform step b07), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b07);
B07) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and two microgrid sides be all consistent respectively, if so, then stop regulate the same period, perform step b09), if not, then perform step b08);
B08) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b07);
B09) close a PCC switching point and the 2nd PCC switching point simultaneously, and send the instruction turning P/Q pattern to PCS energy storage device, judge whether all PCS energy storage devices normally run, if, then closed 3rd PCC switching point, if not, then returns step b09).
Described to PCS energy storage device carry out the same period regulate be specially:
The voltage magnitude of a PCC switching point grid side, frequency and the regulating command same period is sent to the PCS energy storage device being in V/F pattern.
Described PCS energy storage device is provided with at least 4.
Compared with prior art, the present invention is directed to the many PCC point designs existed in micro-grid system, propose a kind of new type of control method switched for PCS energy storage device and from net, have the following advantages:
(1) the present invention arranges a PCC switching point and the 2nd PCC switching point at micro-grid system and bulk power system tie point place, the inside common bus of micro-grid system arranges the 3rd PCC switching point, by the control of 3 PCC switching points, realize the control strategy of micro-grid system to PCS energy storage device, control flexible;
(2) the present invention conveniently can realize electrical breakdown control and power system restoration power supply control.
Accompanying drawing explanation
Fig. 1 is the network architecture schematic diagram of micro-grid system in the present invention;
Fig. 2 is the schematic flow sheet of electrical breakdown rate-determining steps in the present invention;
Fig. 3 is the schematic flow sheet of power system restoration power supply control step in the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.The present embodiment is implemented premised on technical solution of the present invention, give detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.
The present embodiment provides a kind of micro-grid system control method of many PCC point control of Based PC S energy storage device, as shown in Figure 1, this control method arranges a PCC switching point 1 (PCC1) and the 2nd PCC switching point 2 (PCC2) at micro-grid system and bulk power system tie point place, the inside common bus of micro-grid system arranges the 3rd PCC switching point 3 (PCC3), by controlling the control realization micro-grid system of each PCC switching point.PCS energy storage device can arrange multiple stage as required, in the present embodiment, inner common bus is connected with 4 PCS energy storage devices 4.
The control method of the present embodiment specifically comprises:
A) electrical breakdown rate-determining steps;
B) power system restoration power supply control step.
When system is normally run, 3 PCC switching points are in closure state, and as shown in Figure 2, electrical breakdown rate-determining steps is specially:
A01) detect whether there is the instruction of plan isolated island, if so, then enter plan isolated island control strategy, perform step a02), if not, then enter unplanned isolated island control strategy;
A02) judge whether the 3rd PCC switching point closes, if, then micro-grid system is a large microgrid, perform step a03), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, now need to give instruction respectively to 2 micro-capacitance sensor subsystems at detection PCS energy storage device list V/F or many V/F simultaneously, to ensure the continued power of 2 sub-micro-grid systems, perform step a06);
A03) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a04), if not, then perform step a05);
A04) mark a PCS energy storage device and enter V/F pattern, disconnect the 2nd PCC switching point and a PCC switching point successively, the PCS energy storage device to mark sends and turns V/F instruction;
A05) disconnect the 2nd PCC switching point and a PCC switching point successively, send to all PCS energy storage devices simultaneously and turn V/F instruction;
A06) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a07), if not, then perform step a08);
A07) the PCS energy storage device marking two micro-capacitance sensor subsystems respectively enters V/F pattern, disconnects a PCC switching point and the 2nd PCC switching point simultaneously, and the PCS energy storage device to two station symbol notes sends and turns V/F instruction;
A08) disconnect a PCC switching point and the 2nd PCC switching point simultaneously, send to all PCS energy storage devices and turn V/F instruction.
Unplanned isolated island control strategy is with the difference of plan isolated island, the disjunction mode of the one PCC switching point, the 2nd PCC switching point is different, plan isolated island the one PCC switching point and the 2nd PCC switching point are when the 3rd PCC switching point closes, for ensureing that PCS energy storage device V/F patten transformation is stablized, need have successively, can not simultaneously disjunction, unplanned isolated island then can disjunction the one PCC switching point and the 2nd PCC switching point simultaneously.
During micro-grid system isolated power grid, if now power system restoration is powered, then issue simultaneous interconnecting instruction.As shown in Figure 3, power system restoration power supply control step is specially:
B01) judge whether the 3rd PCC switching point closes, if so, then perform step b02), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, need to carry out corresponding command operating to two micro-capacitance sensor subsystems respectively, perform step b06);
B02) judge whether PCS energy storage device is in unit V/F pattern, if so, then the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern, perform step b03), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b03);
Carry out regulating the same period to PCS energy storage device and be specially:
The voltage magnitude of a PCC switching point grid side, frequency and the regulating command same period is sent to the PCS energy storage device being in V/F pattern.
B03) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and microgrid side be all consistent, if so, then stop regulate the same period, perform step b05), if not, then perform step b04);
B04) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b03);
B05) a closed PCC switching point, and the instruction turning P/Q pattern is sent to PCS energy storage device, judge whether all PCS energy storage devices normally run, if so, then close a PCC switching point, complete simultaneous interconnecting, if not, then return step b05);
B06) judge whether PCS energy storage device is in unit V/F pattern, if, then respectively the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern in two micro-capacitance sensor subsystems, perform step b07), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b07);
B07) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and two microgrid sides be all consistent respectively, if so, then stop regulate the same period, perform step b09), if not, then perform step b08);
B08) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b07);
B09) close a PCC switching point and the 2nd PCC switching point simultaneously, and send the instruction turning P/Q pattern to PCS energy storage device, judge whether all PCS energy storage devices normally run, if so, then close the 3rd PCC switching point, complete simultaneous interconnecting, if not, then step b09 is returned).
Claims (6)
1. the micro-grid system control method of many PCC point control of a Based PC S energy storage device, it is characterized in that, this control method arranges a PCC switching point and the 2nd PCC switching point at micro-grid system and bulk power system tie point place, the inside common bus of micro-grid system arranges the 3rd PCC switching point, by controlling the control realization micro-grid system of each PCC switching point, described inner common bus is connected with multiple pc S energy storage device, this control method specifically comprises:
A) electrical breakdown rate-determining steps;
B) power system restoration power supply control step.
2. the micro-grid system control method of many PCC point control of Based PC S energy storage device according to claim 1, is characterized in that, described electrical breakdown rate-determining steps is specially:
A01) detect whether there is the instruction of plan isolated island, if so, then enter plan isolated island control strategy, perform step a02), if not, then enter unplanned isolated island control strategy;
A02) judge whether the 3rd PCC switching point closes, if so, then perform step a03), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, perform step a06);
A03) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a04), if not, then perform step a05);
A04) mark a PCS energy storage device and enter V/F pattern, disconnect the 2nd PCC switching point and a PCC switching point successively, the PCS energy storage device to mark sends and turns V/F instruction;
A05) disconnect the 2nd PCC switching point and a PCC switching point successively, send to all PCS energy storage devices simultaneously and turn V/F instruction;
A06) judge whether PCS energy storage device is in unit V/F pattern, if so, then perform step a07), if not, then perform step a08);
A07) the PCS energy storage device marking two micro-capacitance sensor subsystems respectively enters V/F pattern, disconnects a PCC switching point and the 2nd PCC switching point simultaneously, and the PCS energy storage device to two station symbol notes sends and turns V/F instruction;
A08) disconnect a PCC switching point and the 2nd PCC switching point simultaneously, send to all PCS energy storage devices and turn V/F instruction.
3. the micro-grid system control method of many PCC point control of Based PC S energy storage device according to claim 2, is characterized in that, in described unplanned isolated island control strategy, the 2nd PCC switching point and a PCC switching point are and disconnect simultaneously.
4. the micro-grid system control method of many PCC point control of Based PC S energy storage device according to claim 1, is characterized in that, described power system restoration power supply control step is specially:
B01) judge whether the 3rd PCC switching point closes, if so, then perform step b02), if not, then micro-grid system two micro-capacitance sensor subsystems respectively, perform step b06);
B02) judge whether PCS energy storage device is in unit V/F pattern, if so, then the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern, perform step b03), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b03);
B03) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and microgrid side be all consistent, if so, then stop regulate the same period, perform step b05), if not, then perform step b04);
B04) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b03);
B05) a closed PCC switching point, and the instruction turning P/Q pattern is sent to PCS energy storage device, judge whether all PCS energy storage devices normally run, if so, then close a PCC switching point, if not, then return step b05);
B06) judge whether PCS energy storage device is in unit V/F pattern, if, then respectively the adjustment same period is carried out to the PCS energy storage device being in unit V/F pattern in two micro-capacitance sensor subsystems, perform step b07), if not, then the adjustment same period is carried out to all PCS energy storage devices, perform step b07);
B07) judge that whether voltage magnitude, the phase angle of a PCC switching point grid side and two microgrid sides be all consistent respectively, if so, then stop regulate the same period, perform step b09), if not, then perform step b08);
B08) judge whether regulating time is greater than setting threshold, if so, then regulate the same period unsuccessfully, if not, then readjust, return step b07);
B09) close a PCC switching point and the 2nd PCC switching point simultaneously, and send the instruction turning P/Q pattern to PCS energy storage device, judge whether all PCS energy storage devices normally run, if, then closed 3rd PCC switching point, if not, then returns step b09).
5. the micro-grid system control method of many PCC point control of Based PC S energy storage device according to claim 1, is characterized in that, described to PCS energy storage device carry out the same period regulate be specially:
The voltage magnitude of a PCC switching point grid side, frequency and the regulating command same period is sent to the PCS energy storage device being in V/F pattern.
6., according to the micro-grid system control method of many PCC point control of the arbitrary described Based PC S energy storage device of claim 1-5, it is characterized in that, described PCS energy storage device is provided with at least 4.
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