Summary of the invention
For above-mentioned Unified Power Quality Controller protection act not in time, the problem that safety is the highest, this
Bright proposition is a kind of the most in time, the protection system of the Unified Power Quality Controller that safety is higher.
A kind of protection system of Unified Power Quality Controller, including:
It is separately positioned on the first chopper and second chopper at the two ends of series coupled transformator primary side;Its
In, the described secondary side of series coupled transformator is connected with the part in series of Unified Power Quality Controller;
The branch circuit parallel connection constituted with described series coupled transformator, described first chopper and the second chopper
Anti-parallel thyristor;
Be arranged on described Unified Power Quality Controller part in series and described series coupled Circuit Fault on Secondary Transformer it
Between the 3rd chopper;
It is arranged on the 4th chopper between described Unified Power Quality Controller parallel connection part and load;
Fiveth chopper in parallel with described anti-parallel thyristor;
The controller being connected with described anti-parallel thyristor and each described chopper;
When be short-circuited earth fault time, described controller controls the conducting of described anti-parallel thyristor, described the
Five breaker closings, described first to fourth breaker open operation;
Described controller exports a pair normally opened point and is connected in the trip(ping) circuit of described 5th chopper;
Described 5th chopper exports four tripping operations that normally opened point is connected to described first to fourth chopper respectively
As cascading trip in loop;
Wherein, detect whether when described Unified Power Quality Controller works to occur short circuit grounding fault or
Fault current;It is to control the parallel connection part locking of described Unified Power Quality Controller, described part in series
The bypass of upper brachium pontis, lower brachium pontis locking or upper brachium pontis locking, the bypass of lower brachium pontis, described controller to described instead
Parallel thyristors sends Continuity signal, controls described anti-parallel thyristor and turns on and maintain, described controller pair
Described 5th chopper sends reclosing command, controls described 5th breaker closing, takes over described inverse parallel brilliant
Described series coupled transformator is bypassed by brake tube;Control described first to fourth breaker open operation.
In the protection system of the Unified Power Quality Controller of the present invention, when be short-circuited earth fault time, therefore
Barrier electric current is concatenated coupling transformer primary side, and now, described controller controls described anti-parallel thyristor leads
Logical, described series coupled transformator is bypassed, owing to anti-parallel thyristor reception turn-on command is QA
Time quickly, generally within 10ms, therefore, it is possible to make protection act the quickest;Described 5th breaks
Road device closes a floodgate, and takes over described anti-parallel thyristor and bypass by described series coupled transformator, it is to avoid described the most also
The ON time of connection IGCT is long and affects service life;Described first to fourth breaker open operation, makes institute
Stating Unified Power Quality Controller the most thoroughly to disconnect with system and load, safety is higher.
The protection control method of the protection system of the Unified Power Quality Controller of a kind of present invention, including following
Step:
S101, detects whether short circuit grounding fault or fault current occur, if it is, perform step S102
To S105;
S102, controls the parallel connection part locking of described Unified Power Quality Controller, bridge on described part in series
Arm bypass, lower brachium pontis locking or upper brachium pontis locking, the bypass of lower brachium pontis;
S103, described controller sends conducting to described anti-parallel thyristor and triggers signal, control described anti-the most also
Connection turn on thyristors;
S104, described controller sends reclosing command to described 5th chopper, controls described 5th chopper
Close a floodgate;
S105, described controller sends separating brake instruction, controls described first described first to fourth chopper
Sub-switching operation is carried out to the 4th chopper.
In the protection control method of the protection system of the Unified Power Quality Controller of the present invention, in described unification
Detect whether that short circuit grounding fault or fault current occur during electric energy quality controller work.Control described system
The parallel connection part locking of one electric energy quality controller, on described part in series brachium pontis bypass, lower brachium pontis locking or
Person's upper brachium pontis locking, the bypass of lower brachium pontis, first pass through the submodule locking of internal mode massing multilevel converter
With bypass condition, described Unified Power Quality Controller is protected.Further, described controller to described instead
Parallel thyristors sends Continuity signal, makes described anti-parallel thyristor turn on and maintain, by described series coupled
Transformator bypasses, owing to anti-parallel thyristor receives the turn-on command QA time quickly, generally at 10ms
Within, therefore, it is possible to make protection act the quickest;Then, described controller is to described 5th open circuit
Device sends reclosing command, makes described 5th breaker closing, takes over described anti-parallel thyristor by described series connection
Coupling transformer bypasses, it is to avoid the ON time of described anti-parallel thyristor is long and affects service life;Make
Described first to fourth breaker open operation, makes described Unified Power Quality Controller the most thorough with system and load
Disconnecting, safety is higher.
Detailed description of the invention
Refer to the structural representation that Fig. 2, Fig. 2 are the protection systems of Unified Power Quality Controller of the present invention.
The protection system of described Unified Power Quality Controller, including:
It is separately positioned on the first chopper CB1 and second chopper at the two ends of series coupled transformator primary side
CB2;Wherein, the secondary side of described series coupled transformator connects with the part in series of Unified Power Quality Controller
Connect;
With propping up that described series coupled transformator, described first chopper CB1 and the second chopper CB2 are constituted
The anti-parallel thyristor SCR that road is in parallel;
Be arranged on described Unified Power Quality Controller part in series and described series coupled Circuit Fault on Secondary Transformer it
Between the 3rd chopper CB3;
It is arranged on the 4th chopper CB4 between described Unified Power Quality Controller parallel connection part and load;
With described 5th chopper CB5 in parallel for anti-parallel thyristor SCR;
The controller (not shown) being connected with described anti-parallel thyristor SCR and each described chopper;
When be short-circuited earth fault time, described controller control described anti-parallel thyristor SCR conducting, institute
State the 5th chopper CB5 to close a floodgate, described first to fourth breaker open operation.
In the protection system of the Unified Power Quality Controller of the present invention, when be short-circuited earth fault time, therefore
Barrier electric current is concatenated coupling transformer primary side, and now, described controller controls described anti-parallel thyristor leads
Logical, described series coupled transformator is bypassed, owing to anti-parallel thyristor reception turn-on command is QA
Time quickly, generally within 10ms, therefore, it is possible to make protection act the quickest;Described 5th breaks
Road device closes a floodgate, and takes over described anti-parallel thyristor and bypass by described series coupled transformator, it is to avoid described the most also
The ON time of connection IGCT is long and affects service life;Described first to fourth breaker open operation, makes institute
Stating Unified Power Quality Controller the most thoroughly to disconnect with system and load, safety is higher.Described unification
The protection system of electric energy quality controller is made up of anti-parallel thyristor and chopper.Its use jumbo instead
Parallel thyristors carries out error protection to MMC type UPQC.
The parallel connection part inverter of UPQC is directly connected in the circuit between load and system, the part in series change of current
Device is then via series coupled transformator incoming transport system, as shown in Figure 2.Described MMC type UPQC
The agent structure of connection in series-parallel part is modularization multi-level converter, by the increase of inverter submodule number
Improve capacity and the electric pressure thereof of device, as shown in Figure 1.Described MMC type UPQC inverse parallel is brilliant
Brake tube is arranged on series coupled transformator primary side, and remaining five chopper is separately mounted to series coupled transformation
Device with in system junction, series coupled transformator is connected with system with load junction, UPQC parallel connection part
Place, UPQC part in series and coupling transformer junction and series coupled transformator primary side.
The selection of described anti-parallel thyristor SCR need to consider load-side and be short-circuited institute under failure condition
The maximum fault current being subjected to.
For reaching more preferably to protect control effect, the fit system of each described chopper of described protection system
May be configured as:
Described controller exports a pair normally opened point and is connected in the trip(ping) circuit of described 5th chopper CB5;Institute
State the tripping operations that the 5th chopper CB5 output four is connected to described first to fourth chopper respectively to normally opened point to return
As cascading trip in road.
The described fiveth chopper CB5 output four in parallel with described series coupled transformator primary side is to (passive
Point) normally opened point is connected in the trip(ping) circuit of remaining four chopper respectively as cascading trip;
Described controller a pair (without source point) normally opened point of output of UPQC is connected to and described 5th chopper
In the trip(ping) circuit of CB5, it is ensured that the 5th chopper CB5 described in during UPQC fault first closes a floodgate holding supply lines
Road is unobstructed, then is each turned off remaining 4 chopper;
Further, described 3rd chopper CB3 and described 4th chopper CB4 also can be set and respectively export one
Normally closed point is connected in the closing circuit of described 5th chopper CB5.
2 choppers (the 3rd chopper CB3 and the 4th open circuits at UPQC connection in series-parallel part access system
Device CB4) in arbitrary tripping operation of breaking down, need in parallel with described series coupled transformator 10 primary side
Five chopper CB5 are closed at, and the most above-mentioned 2 choppers respectively export a pair normally closed point and are connected to described
In the closing circuit of the 5th chopper CB5, reach fast linked effect.
Refer to the protection control method that Fig. 3, Fig. 3 are the protection systems of Unified Power Quality Controller of the present invention
Schematic flow sheet.
The protection control method of the protection system of the Unified Power Quality Controller of the present invention, comprises the following steps:
S101, detects whether short circuit grounding fault or fault current occur, if it is, perform step S102
To S105;
In this step, whether detecting system breaks down phenomenon, or whether detecting system breaks down electric current;
Step S102 is then carried out if there is fault or overcurrent phenomenon;If do not broken down and overcurrent phenomenon,
Skip step S102 to continue to run with to step S105, system;
S102, controls the parallel connection part locking of described Unified Power Quality Controller, bridge on described part in series
Arm bypass, lower brachium pontis locking or upper brachium pontis locking, the bypass of lower brachium pontis;
In this step, MMC type UPQC parallel connection side converter blocking upper and lower brachium pontis submodule, series side
Brachium pontis submodule bypass (locking), lower brachium pontis submodule locking (bypass) on inverter;
S103, described controller sends conducting to described anti-parallel thyristor SCR and triggers signal, controls described
Anti-parallel thyristor SCR turns on;
In this step, switch board sends conducting to anti-parallel thyristor SCR and triggers signal, makes inverse parallel brilliant
Brake tube SCR action, anti-parallel thyristor SCR action, shunting device series side coupling transformer;
S104, described controller sends reclosing command to described 5th chopper, controls described 5th chopper
Close a floodgate;
In this step, switch board is to fiveth chopper in parallel with described series coupled transformator primary side
CB5 sends reclosing command, makes the 5th chopper CB5 close a floodgate.
Preferably, after described 5th chopper CB5 closes a floodgate, described controller stops described inverse parallel brilliant
Brake tube SCR sends conducting and triggers signal, controls described anti-parallel thyristor SCR and turns off.Further, make
Anti-parallel thyristor SCR turns off at next current zero-crossing point.
S105, described controller sends separating brake instruction, controls described first described first to fourth chopper
Sub-switching operation is carried out to the 4th chopper.
Switch board sends breaker open operation instruction, makes to arrange series coupled transformator and the first of system junction
Chopper CB1, be arranged on series coupled transformator and load junction the second chopper CB2, be arranged on
UPQC series side and the 3rd chopper CB3 of series coupled transformator junction, to be arranged on UPQC in parallel
Side carries out sub-switching operation with the 4th chopper CB4 of system junction simultaneously, terminates.
In the protection control method of the protection system of the Unified Power Quality Controller of the present invention, in described unification
Detect whether that short circuit grounding fault or fault current occur during electric energy quality controller work.Control described system
The parallel connection part locking of one electric energy quality controller, on described part in series brachium pontis bypass, lower brachium pontis locking or
Person's upper brachium pontis locking, the bypass of lower brachium pontis, first pass through the submodule locking of internal mode massing multilevel converter
With bypass condition, described Unified Power Quality Controller is protected.Further, described controller to described instead
Parallel thyristors sends Continuity signal, makes described anti-parallel thyristor turn on and maintain, by described series coupled
Transformator bypasses, owing to anti-parallel thyristor receives the turn-on command QA time quickly, generally at 10ms
Within, therefore, it is possible to make protection act the quickest;Then, described controller is to described 5th open circuit
Device sends reclosing command, makes described 5th breaker closing, takes over described anti-parallel thyristor by described series connection
Coupling transformer bypasses, it is to avoid the ON time of described anti-parallel thyristor is long and affects service life;Make
Described first to fourth breaker open operation, makes described Unified Power Quality Controller the most thorough with system and load
Disconnecting, safety is higher.
When load side or system side are short-circuited earth fault, system voltage will bear directly against system resistance
Resist and series coupled transformator primary side, due to system impedance and series coupled transformator primary impedance phase
More a lot of than little, major part false voltage will mainly act on transformator primary side, Circuit Fault on Secondary Transformer general
Induce high voltage.Even if UPQC part in series does not works, under the effect of diode uncontrollable rectifier, public
Common DC bus voltage still can raise.The most when a failure occurs it, need to adopt an effective measure device is entered
Row quickly isolates and exits, to avoid fault current that device is caused damage.
If load-side there occurs three-phase shortcircuit earth fault, fault current flows through system impedance and becomes with series coupled
Depressor primary side, in the protection control method of the present invention, the rapid locking of UPQC parallel connection part, part in series
The bypass of upper brachium pontis, lower brachium pontis locking or upper brachium pontis locking, the bypass of lower brachium pontis.Described anti-parallel thyristor SCR
Accepting controller turn-on command quick acting, bypassed by described series coupled transformator, movement time is 10ms
Within, the 5th chopper CB5 accepts controller reclosing command, and first to fourth chopper accepts controller and divides
Lock instructs, and UPQC Safe withdrawing runs, error protection tenth skill.
Rough schematic view such as Fig. 1 of the agent structure-modularization multi-level converter of Unified Power Quality Controller
Shown in, three-phase is in series with inducer by 2N submodule respectively, is divided into upper and lower two brachium pontis.Fault
Under state, by the locking of the submodule of modularization multi-level converter and bypass condition, device need to be protected
Protect.As shown in Figure 1 when in submodule, T1, T2 set to 0, submodule is in blocking;When in submodule
T1, T2 set to 0 respectively, put 1, and submodule is in bypass condition.
The protection system of the Unified Power Quality Controller of the present invention and protection control method thereof also have and following have
Benefit effect:
First, the present invention can quickly bypass string after short trouble occur in load side, system side in 10ms
Connection coupling transformer, it is achieved to UPQC coupling transformer and the protection of series side inverter;
Second, the present invention can complete further system and jump after the serious short trouble 10ms of generation being detected
Lock is stopped transport and is protected, and owing to quickly bypassing series coupled transformator, system short-circuit impedance will not change, be
System higher level's fault protection is unaffected;
3rd, device can be carried out in the case of anti-parallel thyristor tripping by the present invention by breaker actuation
Second protection, improves the reliability and safety of device.
Embodiment described above only have expressed the several embodiments of the present invention, and it describes more concrete and detailed,
But therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that, for this area
Those of ordinary skill for, without departing from the inventive concept of the premise, it is also possible to make some deformation and
Improving, these broadly fall into protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be with appended
Claim is as the criterion.