CN103166180A - Method and device for judging overload shedding for power system transformer - Google Patents
Method and device for judging overload shedding for power system transformer Download PDFInfo
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- CN103166180A CN103166180A CN2013100976298A CN201310097629A CN103166180A CN 103166180 A CN103166180 A CN 103166180A CN 2013100976298 A CN2013100976298 A CN 2013100976298A CN 201310097629 A CN201310097629 A CN 201310097629A CN 103166180 A CN103166180 A CN 103166180A
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Abstract
The invention discloses a method for judging overload shedding for a power system transformer. The method comprises the following steps of: S1, judging whether the overload shedding function of the transformer is input or not; S2, judging whether the load of the low voltage side of the transformer is overload or not; S3, judging whether the overload time of the transformer exceeds a definite time value or not; S4, judging whether tripping rounds are set in an overload shedding device of the transformer or not; S5, sequentially tripping partial circuit switches connected with the low voltage side of the transformer off by the overload shedding device of the transformer according to the tripping rounds; and S6, delaying for X seconds, and then returning to the step S2. A device for implementing the method comprises a transformer low voltage side current monitoring unit, an analog/digital (A/D) conversion unit, a logic control unit and a tripping output unit which are sequentially connected, wherein the input end of the current monitoring unit is connected with the output of a secondary winding of a transformer low voltage side current transformer, and the output of the tripping output unit is connected to a tripping coil control power supply of a tripping relay. The method and the device have the advantages that 1) the operation of the transformer is not required to be stopped during overload; 2) automatic operation is realized; and 3) load shedding is prevented from being artificially delayed.
Description
Technical field
The present invention relates to a kind of 110kV of electric power system and the transformer of above voltage and judge the method for transshipping cutting load.The invention still further relates to the device of the power system transformer judgement overload cutting load of realizing described method.
Background technology
Transformer-supplied: as depicted in figs. 1 and 2, traditional transformer and low-pressure side bus are for electrical schematic.Electric current flows into from the high-pressure side 2 of transformer 1, flows out from low-pressure side 3 after the transformer conversion, and the low-side switch of flowing through 4, low-pressure side current transformer 5 are until flow into bus 6, supply power to the user from bus to circuit F1 to circuit Fn again.Bus current also can supply power to another section bus 11 through bus connection switch 10.
Transformer belt load-bearing capacity: 12 circuits of normal access on the 110kV of electric power system at present and the low-pressure side bus of above grade transformer, article one, the on-load ability of circuit is about 500 amperes of left and right, if 12 all oeprations at full load of circuit, step down side will be exported 6000 Ampere currents, well beyond the transformer load ability.Therefore, the whole oeprations at full load of step down side institute's link will exceed the transformer-supplied ability.
Transformer can surpass its rated capacity operation a period of time.At present often with 1.0 to 1.2 times of transformer rated capacity as overload criteria.Also need not be out of service immediately when therefore, the load of transformer surpasses its rated capacity.
Present protection equipment for transformer also has overload protection function: when transformer overload; protective device monitors electric current and surpasses set point; start trip avoidance function after time-delay, tripping step down side switch or tripping bus connection switch are to guarantee that transformer can be because long term overloading damages.Table 1 is the step down side overload protection constant value tripping operation table of 63 megavolt-amperes, and this step down side rated current is 3500 amperes.
| Defencive function | Current ration | Overload time | Start-up function |
| Overload current 1 | 3800 amperes | 5 seconds | Warning is posted a |
| Overload current | |||
| 2 | 4350 amperes | 1 second | Tripping low-side switch, bus connection switch |
Certain step down side overload protection constant value tripping operation table of table 1.
Existing protection equipment for transformer is by low-pressure side current transformer monitoring low-pressure side electric current, and the determination methods of overload starting is described below:
When 1) protection equipment for transformer monitored the low-pressure side electric current and reaches the overload current definite value 1 of low value, after time-delay, if electric current still surpasses overload current definite value 1, the protective device warning of posting a letter determined processing method by the operator on duty.
When 2) protection equipment for transformer monitors the low-pressure side electric current and reaches the overload current definite value 2 of high value; after time-delay; if electric current still surpasses overload current definite value 2, protective device is sent out trip signal to step down side switch and bus connection switch, automatically excises all loads of transformer.
There is following shortcoming in above-mentioned protection equipment for transformer overload start mode:
Need excise whole loads when 1) transshipping: when transformer load surpasses the overload current definite value of high value, will starting transformer overcurrent tripping function, tripping low-side switch and bus connection switch make all circuits on low-pressure side bus all lose power supply, stop supplying power for outside;
Need when 2) transshipping by artificial treatment: when transformer load surpasses the overload current of low value, will start the function of posting a letter of reporting to the police, the inessential line load of operator on duty's cut-out;
3) overload-alarm is processed untimely with the expansion accident: when transformer load surpasses the overload current definite value of low value; will start the function of posting a letter of reporting to the police; if the operator on duty does not have monitoring on the scene; timely cut-out line load; and transformer load continues to increase, and when reaching the overload current definite value of high value, protective device is with tripping low-side switch and bus connection switch; make bus loss of pressure, all circuit loses power supply.
Summary of the invention
First technical problem to be solved by this invention just is to provide and a kind ofly transformer overload can be detected and send out trip signal and the method for the power system transformer judgement overload cutting load that is unlikely to all to stop power supply in all cases in when overload from trend low-pressure side line switching.
For solving the problems of the technologies described above, the technical scheme that the present invention takes is as follows:
A kind of determination methods of transformer overload cutting load logic comprises the steps:
S1 judges whether transformer overload cutting load function drops into: do not drop into termination, drop into and enter next step;
S2 judges whether the step down side load transships: nonoverload stops, and overload enters next step;
S3 judges whether overtime definite value of transformer load overload time: the time that is no more than stops, and overtime enters next step;
S4 judges whether transformer overload cutting load device sets the tripping operation round: do not set termination, set and enter next step;
The partial line way switch that S5 transformer overload cutting load device connects by tripping operation round tripping step down side successively;
S6 time-delay X (can be set by the user) after second, returned to step S2.
Second technical problem to be solved by this invention just is to provide a kind of device of realizing the power system transformer judgement overload cutting load of said method.
For solving the problems of the technologies described above, the technical scheme that the present invention takes is as follows:
A kind of device 1 of power system transformer judgement overload cutting load, comprise successively the step down side current monitoring unit 2, A/D converting unit 3, logic control element 4 and the tripping operation output unit 5 that connect, the input termination transformer low voltage of current monitoring unit 2 is the secondary side winding output of current transformer 21, and the output of tripping operation output unit 5 is connected to the breaking coil of tripping relay 6 and controls power supply.
Described current monitoring unit 4 comprises and is arranged in current transformer 21 and the current cable 22 that step down side connects successively; the composition of described logic control element 4 and annexation are: whether overload cutting load function drops into judge whether signal 101 and overload cutting load device are set tripping operation round judgement signal 102 and inputted respectively first and logic element 105, the traffic overload time whether the overtime definite value judge signal 103 and low-pressure side load whether transship judgement signal 104 input respectively second with logic element 106, first exports respectively the 8th and logic element 107 with logic element 105 and second to logic element 106, the 8th with the output of logic element 107 tripping relay 109 to round 1 after the first tripping operation outlet brace 108, the output of the tripping relay 109 of round 1 after the first delay cell 1010 with low-pressure side load whether transship judgement signal 104 input respectively the 4th with logic element 1011, the 4th with the output of logic element 1011 tripping relay 1013 to round 2 after the second tripping operation outlet brace 1012, the output of the tripping relay 1013 of round 2 after the second delay cell 1014 with low-pressure side load whether transship judgement signal 4 input respectively the 5th with logic element 1015, the 5th with the output of logic element 1015 tripping relay 1017 to round 3 after the 3rd tripping operation outlet brace 1016,-------so same structure, until the tripping relay 1018 of starting round 5.
The tripping relay of tripping operation one round can start a line switching or many line switching tripping operations arbitrarily.
Operation principle:
The step down side current transformer changes into little electric current with large electric current with mutual inductor ratio, is sent to the current sample module by current cable, then converts Weak current to; Weak current is sent to the A/D converting unit, converts the digital quantity current signal to, is sent to logic control element; The CUP arithmetic element is calculated electric current and whether is reached the overload current definite value, if surpass, signals selectively to the output unit that trips by the tripping operation round, by the tripping operation of tripping operation output unit starting transformer low-pressure side partial line way switch, cut-out load; If electric current is no more than the overload current definite value, this device is failure to actuate.
Compared with prior art, the present invention has following beneficial effect:
1) transformer overload need not to stop transport, and only needs the cut-out line load.When transformer overload, apparatus of the present invention can monitor electric current and surpass the overload current definite value, and starting overload cutting load function connects the partial line way switch to low-pressure side and sends out trip signal, and the cut-out line load, reduce transformer load selectively;
2) transformer overload cutting load follow procedure automatic operation.The inventive method is calculated with the CPU computing and is judged whether to reach the cutting load condition, and the line switching by setting round judgement excision load need not manual operation, and can avoid the people is that misoperation causes the excision line switching incorrect;
3) stop manually to incur loss through delay cutting load and cause the expansion accident.Apparatus of the present invention can be started the cutting load function automatically, and follow procedure sends the order of jumping circuit switch.All operations all can be by the delay time action of adjusting.Even be applied in unwatched transformer station, also cut-out is loaded automatically.Avoid transformer overload tripping step down side switch, cause whole circuits to lose power supply.
Description of drawings
Fig. 1 is transformer overload cutting load apparatus structure schematic diagram of the present invention;
Fig. 2 is transformer overload cutting load logic judgement schematic diagram of the present invention;
It is transformer overload cutting load method flow diagram of the present invention in Fig. 3.
Embodiment
As shown in Figure 3, the determination methods of transformer overload cutting load logic of the present invention comprises the steps:
S1 judges whether transformer overload cutting load function drops into: do not drop into termination, drop into and enter next step;
S2 judges whether the step down side load transships: nonoverload stops, and overload enters next step;
S3 judges whether overtime definite value of transformer load overload time: the time that is no more than stops, and overtime enters next step;
S4 judges whether transformer overload cutting load device sets the tripping operation round: do not set termination, set and enter next step;
The line switching that S5 transformer overload cutting load device connects by tripping operation round tripping some transformers low-pressure side successively;
X is after second in the S6 time-delay, returns to step S2.
As shown in Figure 1, realize the device 1 of the power system transformer judgement overload cutting load of said method, comprise the step down side current monitoring unit 2, A/D converting unit 3, logic control element 4 and the tripping operation output unit 5 that connect successively; Current monitoring unit 2 comprises and is arranged in current transformer 21 and the current cable 22 that step down side connects successively; The input termination transformer low voltage of current monitoring unit 2 is the secondary side winding output of current transformer 21, and the output of tripping operation output unit 5 is connected to the breaking coil of tripping relay 6 and controls power supply.
At first, draw the little electric current of secondary from the secondary winding of step down side current transformer 21 with current cable 22, the little electric current of secondary is linked into the input of current monitoring unit 2, convert Weak current to through current monitoring unit 2 internal current instrument transformers, Weak current is input to A/D converting unit 3, converts the digital quantity current signal to, and the digital quantity current signal is input to logic control element 4, calculate this digital quantity current signal by logic control element, judge whether electric current surpasses the overload current value.
the composition of logic control element 4 and annexation are: whether overload cutting load function drops into judge whether signal 101 and overload cutting load device are set tripping operation round judgement signal 102 and inputted respectively first and logic element 105, the traffic overload time whether the overtime definite value judge signal 103 and low-pressure side load whether transship judgement signal 104 input respectively second with logic element 106, first exports respectively the 8th and logic element 107 with logic element 105 and second to logic element 106, the 8th with the output of logic element 107 tripping relay 109 to round 1 after the first tripping operation outlet brace 108, the output of the tripping relay 109 of round 1 after the first delay cell 1010 with low-pressure side load whether transship judgement signal 104 input respectively the 4th with logic element 1011, the 4th with the output of logic element 1011 tripping relay 1013 to round 2 after the second tripping operation outlet brace 1012, the output of the tripping relay 1013 of round 2 after the second delay cell 1014 with low-pressure side load whether transship judgement signal 4 input respectively the 5th with logic element 1015, the 5th with the output of logic element 1015 tripping relay 1017 to round 3 after the 3rd tripping operation outlet brace 1016,-------so same structure, until the tripping relay 1018 of starting round 5.
if the step down side electric current surpasses the overload current value, transformer will transship, transformer overload cutting load device internal processes is by the starting of tripping operation round, to 5 trip signals of tripping operation output unit, the cutting load order that tripping operation output unit 5 is received logic control element, adhesive output contact 51, the adhesive of output contact 51 is connected the coil of tripping relay 6 and is controlled power supply, the coil of tripping relay 6 is controlled power supply through control cables 51, output contact 51 forms path, the line switching that on starting tripping relay 6, normal opened contact connects, the line switching institute on-load that on excision tripping relay 6, normal opened contact connects.
Tripping operation round setting principle: unessential circuit is arranged on preferential round, and important line is arranged on the hysteresis round and does not even access the tripping operation output unit.
Transformer overload cutting load logic judging circuit of the present invention is as shown in Figure 2:
S1) whether judgement overload cutting load function drops into;
S2) judgement is whether the line tripping round is set;
S3) judgement is whether transformer load surpasses definite value;
S4) judgement is the transformer overload time whether to surpass definite value:
If have, sending out trip signal to tripping tripping operation round is 1 output contact, and making and being connected on the tripping operation round is line switching tripping operation on 1 output contact; Tripping tripping operation round be 1 line switching after, through time-delay Tset, continue press the S3 judgement after time-delay, be 2 output contact to the round that trips as satisfying, sending out trip signal, making and being connected on the tripping operation round is that line switching on 2 output contact trips.Continue judgement, until till starting the 6th line switching tripping operation of taking turns.As not satisfying S3 in deterministic process, transformer nonoverload is described, the judgement of overload cutting load is so far, and initial condition is returned in the logic judgement.
If nothing is failure to actuate, continue to monitor the transformer load situation.
Each is taken turns on the control loop of tripping operation outlet, being provided with tripping operation outlet brace 1, selects whether to use trip avoidance function on this round by the user.The brace that closes, tripping operation is connected, and the cutting load function can be started this line switching tripping operation; Disconnect sheet, overload cutting load function still can be started, but can the jumping circuit switch.
The transformer overload computational methods:
Ie-step down side rated current, unit: ampere;
S-transformer rated capacity, unit: volt-ampere;
U-step down side rated voltage, unit: volt;
T-step down side current transformer ratio
Ie=[S/（√3*U）]/T
Transformer overload exceeds the transformer rated current with transformer and judges.
Consider that transformer has overload capacity, the transformer overload current value can be slightly larger than load current value, but should jump less than transformer the overload current value of low-side switch.
Therefore optional transformer overload cutting load electric current I max=1.1～1.2Ie, transship the optional 5-15 of time-delay Tset second.
Claims (2)
1. the determination methods of a transformer overload cutting load logic, comprise the steps:
S1 judges whether transformer overload cutting load function drops into: do not drop into termination, drop into and enter next step;
S2 judges whether the step down side load transships: nonoverload stops, and overload enters next step;
S3 judges whether overtime definite value of transformer load overload time: the time that is no more than stops, and overtime enters next step;
S4 judges whether transformer overload cutting load device sets the tripping operation round: do not set termination, set and enter next step;
The partial line way switch that S5 transformer overload cutting load device connects by tripping operation round tripping step down side successively;
X is after second in the S6 time-delay, returns to step S2.
2. realize the device (1) of the power system transformer judgement overload cutting load of method as claimed in claim 1 for one kind, it is characterized in that: comprise the step down side current monitoring unit (2), A/D converting unit (3), logic control element (4) and the tripping operation output unit (5) that connect successively, the input termination transformer low voltage of current monitoring unit (2) is the secondary side winding output of current transformer (21), and the output of tripping operation output unit (5) is connected to the breaking coil of tripping relay (6) and controls power supply;
composition and the annexation of described logic control element (4) are: whether overload cutting load function drops into judge whether signal (101) and overload cutting load device are set the tripping operation round and judged that signal (102) inputs respectively first and logic element (105), the traffic overload time whether the overtime definite value judge signal (103) and low-pressure side load whether transship judgement signal (104) input respectively second with logic element (106), first with logic element (105) and second and logic element (106) export respectively the 8th and logic element (107) to, the 8th with the output of logic element (107) tripping relay (109) to round 1 after the first tripping operation outlet brace (108), the output of the tripping relay of round 1 (109) after the first delay cell (1010) with low-pressure side load whether transship judgement signal (104) input respectively the 4th with logic element (1011), the 4th with the output of logic element (1011) tripping relay (1013) to round 2 after the second tripping operation outlet brace (1012), the output of the tripping relay of round 2 (1013) after the second delay cell (1014) with low-pressure side load whether transship judgement signal (4) input respectively the 5th with logic element (1015), the 5th with the output of logic element (1015) tripping relay (1017) to round 3 after the 3rd tripping operation outlet brace (1016),-------so same structure, until the tripping relay (1018) of starting round 5.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103489259A (en) * | 2013-08-16 | 2014-01-01 | 国家电网公司 | High-voltage user local cost control intelligent electric energy meter |
| CN104362589A (en) * | 2014-11-27 | 2015-02-18 | 国家电网公司 | Sectionalized protection device for high overload distribution transformer |
| CN105404780A (en) * | 2015-11-25 | 2016-03-16 | 国网山东省电力公司电力科学研究院 | Multi-parameter integrated analysis transformer overload capability evaluating method |
| CN105743082A (en) * | 2016-04-27 | 2016-07-06 | 武汉大学 | Overload switching device suitable for DC power distribution system |
| CN109560541A (en) * | 2018-11-05 | 2019-04-02 | 国网宁夏电力有限公司电力科学研究院 | A kind of overload and blanking method |
| CN110867829A (en) * | 2019-10-25 | 2020-03-06 | 广东电网有限责任公司 | Distribution transformer protection measurement and control device based on transformer overload capacity protection |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2116276U (en) * | 1992-02-18 | 1992-09-16 | 俞大泓 | Circuit breaker with time controlling and load limiting |
| CN101299532A (en) * | 2007-11-08 | 2008-11-05 | 江苏省电力公司 | Closed-loop self-adaption emergency control method for large electric network ''('centralized coordination, demixing control') '' |
| CN101557101A (en) * | 2008-10-14 | 2009-10-14 | 吴宏斌 | Relay protection method for eliminating failure in transformer dead zone |
| CN202026149U (en) * | 2011-04-29 | 2011-11-02 | 河南省电力公司驻马店供电公司 | Electric network voltage limit load centralized control system |
| CN202759216U (en) * | 2012-09-07 | 2013-02-27 | 常熟市森源电气科技有限公司 | Overload alarm device for power transformer |
-
2013
- 2013-03-25 CN CN201310097629.8A patent/CN103166180B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2116276U (en) * | 1992-02-18 | 1992-09-16 | 俞大泓 | Circuit breaker with time controlling and load limiting |
| CN101299532A (en) * | 2007-11-08 | 2008-11-05 | 江苏省电力公司 | Closed-loop self-adaption emergency control method for large electric network ''('centralized coordination, demixing control') '' |
| CN101557101A (en) * | 2008-10-14 | 2009-10-14 | 吴宏斌 | Relay protection method for eliminating failure in transformer dead zone |
| CN202026149U (en) * | 2011-04-29 | 2011-11-02 | 河南省电力公司驻马店供电公司 | Electric network voltage limit load centralized control system |
| CN202759216U (en) * | 2012-09-07 | 2013-02-27 | 常熟市森源电气科技有限公司 | Overload alarm device for power transformer |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103489259A (en) * | 2013-08-16 | 2014-01-01 | 国家电网公司 | High-voltage user local cost control intelligent electric energy meter |
| CN103489259B (en) * | 2013-08-16 | 2016-06-29 | 国家电网公司 | A kind of high-voltage user local cost control intelligent electric energy meter |
| CN104362589A (en) * | 2014-11-27 | 2015-02-18 | 国家电网公司 | Sectionalized protection device for high overload distribution transformer |
| CN104362589B (en) * | 2014-11-27 | 2017-08-25 | 国家电网公司 | A kind of sectionalised protection device for high overload distribution transformer |
| CN105404780A (en) * | 2015-11-25 | 2016-03-16 | 国网山东省电力公司电力科学研究院 | Multi-parameter integrated analysis transformer overload capability evaluating method |
| CN105404780B (en) * | 2015-11-25 | 2019-03-26 | 国网山东省电力公司 | A kind of transformer overload capability assessment method of multiparameter exponential family |
| CN105743082A (en) * | 2016-04-27 | 2016-07-06 | 武汉大学 | Overload switching device suitable for DC power distribution system |
| CN109560541A (en) * | 2018-11-05 | 2019-04-02 | 国网宁夏电力有限公司电力科学研究院 | A kind of overload and blanking method |
| CN109560541B (en) * | 2018-11-05 | 2022-04-22 | 国网宁夏电力有限公司电力科学研究院 | Overload parallel cutting method |
| CN110867829A (en) * | 2019-10-25 | 2020-03-06 | 广东电网有限责任公司 | Distribution transformer protection measurement and control device based on transformer overload capacity protection |
| CN110867829B (en) * | 2019-10-25 | 2022-04-19 | 广东电网有限责任公司 | Distribution transformer protection measurement and control device based on transformer overload capacity protection |
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