Transformer station's automatic voltage control method based on the control command coding
Technical field
The invention belongs to electric power system automatism voltage control technical field, transformer station's automatic voltage control method of particularly encoding based on control command.
Background technology
Automatism voltage control (AVC, Automatic Voltage Control) system is one of most important automatic control system of electric power system.The AVC system mainly adopts the tertiary voltage control model at present; Whole AVC system is divided into three levels: one-level voltage control (PVC; Primary Voltage Control); Secondary voltage control (SVC, Secondary Voltage Control) and tertiary voltage control (TVC, Tertiary Voltage Control).
The one-level voltage control is according to the difference of the object of control; Can be divided into power plant's one-level voltage control and transformer station's one-level voltage control: power plant's one-level voltage control is the control of the automatic excitation regulator equipment such as (AVR) to power generator; Since need the factor of consideration very complicated, therefore, in order to realize the closed-loop control of AVC system; Also need special AVC power substation be set at the power plant place, corresponding is provided with the AVC main website in the regional power grid control centre.The AVC main website carries out three grades and secondary voltage control calculating, according to result of calculation, issues the instruction of generator high voltage bus voltage control to the AVC power substation.After the AVC power substation is received the control command of generator high voltage bus; According to each equipment running in the power plant; Calculate the excitation regulation instruction that generates each operating generator; The control command that generator high voltage bus voltage follower AVC main website is issued, the voltage-controlled time constant of one-level generally are second levels.Similarly, transformer station's one-level voltage control also can adopt AVC transformer station substation control mode, promptly at the transformer station place AVC substation is set, and carries out the control command that the AVC main website issues.Control command is the idle regulated quantity of transforming plant main transformer depressor low-pressure side; Perhaps on-load tap-changing transformer gear regulated quantity; After the transformer station substation receives control command, select transforming plant main transformer depressor low-pressure side reactive apparatus to carry out the switching operation voluntarily and perhaps carry out the operation of on-load tap-changing transformer shift.
The AVC main website that the regional power grid control centre is provided with accomplishes three grades, secondary voltage control function.Wherein secondary voltage control is to liking power plant or transformer station.If controlling object is a power plant; In a control cycle (routine is 5 minutes), the regional maincenter busbar voltage optimization target values according to tertiary voltage control provides adopts sensitivity algorithm; In conjunction with the regulating power that send on the AVC power substation; COMPREHENSIVE CALCULATING goes out the relevant generator high voltage bus voltage control desired value of maincenter bus therewith, and issues control command and this power plant is carried out voltage control for the AVC power substation, and one-period issues the control command of a round.If the controlling object of secondary voltage control is a transformer station, the optimization target values of the regional maincenter busbar voltage that provides according to three grades of controls adopts sensitivity algorithm to obtain the busbar voltage control target of transformer stations all in this zone.But this desired value can not directly be used for control, and this and power plant's secondary voltage control are different.On the one hand, because the equipment of transformer station's control is discrete device, the voltage control of transformer station is discontinuous, has step evolution; On the other hand; Need take all factors into consideration the security constraint and the requirement of regulating target of the busbar voltage of high, medium and low three sides in the transformer station; Therefore in transformer station's secondary voltage control; Need be according to the equipment operation situation of transformer station, the regional maincenter busbar voltage optimization target values that provides in conjunction with tertiary voltage control carried out analysis-by-synthesis and calculated, and the control result of current available discrete device is estimated; Just can determine whether control command controlled and that generation equipment is concrete, be handed down to AVC transformer station substation and carry out.
Tertiary voltage control is calculated based on overall voltage and reactive power optimization; According to the idle distribution of present the whole network; Taking all factors into consideration the idle of power plant, transformer station exerts oneself and spare condition; Under the condition of considering security constraints such as voltage is qualified, trend is not out-of-limit, decreasing minimum with net is that optimization aim is optimized calculating, provides the optimum reactive Voltage Optimum desired value of the whole network.Because electric network reactive-load has distributivity and zonal characteristics; The AVC system is divided into several regions according to the characteristic of reactive power with electrical network automatically; Each zone selects main critical busses as the maincenter bus, and the voltage control target of maincenter bus adopts the given target of overall idle work optimization.Equipment in the same zone has close coupling property on the reactive power characteristic; Interregional equipment then possesses loose coupling property; The thinking of this subregion control meets the principle of electric network reactive-load layering and zoning control; By the on-line automatic completion of system during simultaneously this subregion, be " soft sectoring ", can adapt to the development and change of electrical network.
During AVC system actual motion, issue in the process of control command to AVC transformer station, will face two major issues in the AVC main website.One of which, when AVC main website and AVC transformer station substation data source not simultaneously, possibly have error in measurement, if directly descend main transformer low-pressure side idle work optimization desired value, can produce the situation of incorrect idle adjusting direction.For example the idle value of the current sampling of transforming plant main transformer depressor low-pressure side obtained of AVC main website is 45MVAR (capacitive); And the idle value of current sampling that AVC transformer station substation obtains through other data source is 55MVAR (capacitive); The main transformer low-pressure side idle work optimization desired value that AVC main website side is carried out secondary voltage control calculating generation is 50MVAR (capacitive); It is the idle input of AVC main website expectation main transformer low-pressure side 5MVAR capacitive reactive power; But; If directly assign main transformer low-pressure side idle work optimization desired value 50MVAR (capacitive), then the operation of the idle 5MVAR of the withdrawing from capacitive reactive power of main transformer low-pressure side can be made in AVC transformer station substation, expects the in the opposite direction of adjusting with the AVC main website; They are two years old; Because of communication port disturbs, when continuous identical control command was received in AVC transformer station substation, this moment, AVC transformer station substation can not judge whether this control command is repetitive instruction; If, probably cause the toning of transformer substation voltage according to receiving that control command regulates.
Summary of the invention
The object of the invention is the weak point that overcomes prior art; A kind of transformer station's automatic voltage control method based on the control command coding is proposed; This method be in the AVC main website when reactive apparatus regulated quantity and the transformer gear regulated quantity of transforming plant main transformer depressor low-pressure side are sent in AVC transformer station substation; Adopt a kind of coded system, accurately receive the secondary voltage control instruction that the AVC main website is assigned, carry out the secondary voltage control strategy to guarantee AVC transformer station substation; Follow the controlled target that the AVC main website sets, finally reach effect the automatism voltage control of transformer station.
The transformer station's automatic voltage control method based on the control command coding that the present invention proposes is characterized in that, may further comprise the steps:
1) secondary voltage control cycle, the AVC main website gathers the current throwing of transforming plant main transformer depressor low-pressure side reactive apparatus and moves back state, carries out transformer station's secondary voltage control and calculates, and produces the regulated quantity of transforming plant main transformer depressor low-pressure side reactive apparatus.When transformer station is equipped with the Loading voltage regulator transformer and is set at adjustable gears, gather the current gear of transformer of carrying to be arranged and calculate and produce on-load tap-changing transformer gear regulated quantity;
2) the AVC main website value of regulating according to transforming plant main transformer depressor low-pressure side reactive apparatus needs with regulate direction and generate transformer station's control command coding, this control command coding by transforming plant main transformer depressor low-pressure side reactive apparatus control command coding and on-load tap-changing transformer separately control command coding two parts forms (main transformer of installing when transformer station is the Loading voltage regulator transformer and generates on-load tap-changing transformer parted hair control command when being set at adjustable gears and encode):
Wherein, transforming plant main transformer depressor low-pressure side reactive apparatus control command is encoded to 4 integers, and each bit value is defined as:
The idle adjusting direction of thousands digit value representation main transformer low-pressure side with " 1 " expression excision capacitive reactive power, drops into capacitive reactive power with " 2 " expression, and other numerical value are thought disable instruction;
Hundred bit value represent that a control command issues round, and numerical value increases progressively circulation from " 1 "-" 5 ", guarantee when sending instructions under the AVC main website is each that this bit value is different with last round instruction; If hundred bit value in the scope of " 1 "-" 5 ", are not thought disable instruction; The control command coding of going up round is preserved in AVC transformer station substation, obtain the control command coding of new round after, if find that hundred bit value of this control command coding are identical with last round numerical value, think this not renewal of round instruction;
Ten is the value that drops into or excise transforming plant main transformer depressor low-pressure side capacitive reactive power with the units value, and span is the positive integer of " 0 "-" 9 ", and unit is MVAR; If currently need not increase or reduce transforming plant main transformer depressor low-pressure side capacitive reactive power, ten be encoded to " 00 " with a position;
On-load tap-changing transformer control command separately is encoded to 4 integers, and each bit value defined declaration is following:
Thousands digit value representation on-load tap-changing transformer is regulated direction separately, rises separately with " 1 " expression, falls separately with " 2 " expression, and other numerical value are thought disable instruction;
Hundred bit value represent that an instruction issues round, and numerical value increases progressively circulation from " 1 "-" 5 ", guarantee when sending instructions under the AVC main website is each that this bit value is different with last round instruction; If hundred bit value in the scope of " 1 "-" 5 ", are not thought disable instruction; The control command coding of going up round is preserved in AVC transformer station substation, obtain the control command coding of new round after, if find that hundred bit value of this control command coding are identical with last round numerical value, think this not renewal of round instruction;
Ten with the units value for rising separately or falling gear value separately, once at most only rise or fall 1 grade of parted hair, thus ten have only " 01 " perhaps " 00 " with an effective value of position, other numerical value are thought disable instruction;
3) the AVC main website sends main transformer low-pressure side reactive apparatus control command to AVC transformer station substation; And when transformer station is equipped with the Loading voltage regulator transformer and is set at adjustable gears; Send on-load tap-changing transformer control command separately through the different communication passage; AVC transformer station decodes according to the definition of coding numerical value after receiving the substation control command, carries out real-time regulated to transforming plant main transformer depressor low-pressure side is idle with the on-load tap-changing transformer gear according to decoded control command then; If AVC transformer station substation surpasses when not receiving the legal control command of having upgraded in 15 minutes, think that the AVC main website withdraws from, AVC transformer station substation automatically switches to local runtime, controls according to AVC transformer station substation predetermined manner; If AVC transformer station substation is received the legal control command of having upgraded again, transfer automatically then that to receive AVC main website control command be distant place state of a control to;
4) after AVC main website control command issues and finishes, wait for getting into the next round secondary voltage control cycle, change step 1)
Characteristics of the present invention and effect
The present invention is the transformer station's automatic voltage control method that proposes based on the control command coding.Two major issues that control command occurs when adopting 4 integer-valued coded systems, this coded system to consider AVC system actual motion.One of which; What control command was assigned is the idle increment of transforming plant main transformer depressor low-pressure side; But not directly assign optimization target values; Can avoid like this occurring when AVC main website and AVC transformer station substation data source not simultaneously, possibly have error in measurement, thereby produce the situation of incorrect idle adjusting direction.Its two, encoded packets contain control command round information, avoid disturbing because of communication port, when continuous identical control command is received in AVC transformer station substation, can judge that whether this control command is upgraded, and avoids causing the toning of transformer substation voltage according to round information.And, if the control command of new round is not received in the interior AVC transformer station of certain hour substation, think that then the AVC main website withdraws from, AVC transformer station substation transfers local control model to.If AVC transformer station substation is received new control command again, then transferring the instruction of reception AVC main website automatically to is distant place state of a control.Transformer station's control command coded system that the present invention proposes has considered that employing issues control increment and two key factors of control command round information, can guarantee the actual normal operation of AVC system.
The method that the present invention proposes can be integrated in the on-the-spot operational system, realizes the automatism voltage control to transformer station.
Embodiment
The transformer station's automatic voltage control method based on the control command coding that the present invention proposes specifies as follows:
The present invention includes following steps:
1) a secondary voltage control cycle (routine is 5 minutes) beginning; The AVC main website gathers the current throwing of transforming plant main transformer depressor low-pressure side reactive apparatus and moves back state; Carry out transformer station's secondary voltage control and calculate, produce the regulated quantity of transforming plant main transformer depressor low-pressure side reactive apparatus.When transformer station is equipped with the Loading voltage regulator transformer and is set at adjustable gears, gather the current gear of transformer of carrying to be arranged and calculate and produce on-load tap-changing transformer gear regulated quantity (the regulated quantity computational methods are routine techniques); For example No. 1 main transformer low-pressure side of A transformer station reactive apparatus need drop into the 45MVAR capacitive reactive power.This main transformer is an on-load tap-changing transformer, and adjustable gears, and current gear is " 1 ", and regulating target is " 2 " shelves, raises one grade.
2) the AVC main website value of regulating according to transforming plant main transformer depressor low-pressure side reactive apparatus needs with regulate direction and generate transformer station's control command coding, this control command coding by main transformer low-pressure side reactive apparatus control command coding and on-load tap-changing transformer separately control command coding two parts forms (main transformer of installing when transformer station is the Loading voltage regulator transformer and generates on-load tap-changing transformer parted hair control command when being set at adjustable gears and encode):
Wherein, for avoiding transmitting negative value, main transformer low-pressure side reactive apparatus control command is encoded (hereinafter to be referred as idle instruction), and this instruction is 4 integers, and each bit value is defined as:
The idle adjusting direction of thousands digit value representation main transformer low-pressure side with " 1 " expression excision capacitive reactive power, drops into capacitive reactive power with " 2 " expression, and other numerical value are thought disable instruction;
Hundred bit value represent that a control command issues round (control cycle issues a round control command), and numerical value increases progressively circulation from " 1 "-" 5 ", and the AVC main website guarantees when issuing control command that this bit value is different with last round control command at every turn; If hundred bit value in the scope of " 1 "-" 5 ", are not thought disable instruction; The control command coding of going up round is preserved in AVC transformer station substation, obtain the control command coding of new round after, if find that hundred bit value of this control command coding are identical with last round numerical value, think this not renewal of round instruction;
Ten is the value that drops into or excise transforming plant main transformer depressor low-pressure side capacitive reactive power with the units value, and span is the positive integer of " 0 "-" 9 ", and unit is MVAR; If currently need not increase or reduce transforming plant main transformer depressor low-pressure side capacitive reactive power, ten be encoded to " 00 " with a position then, this control command is idle hold instruction;
For example, first round, the AVC main website needs the capacitive reactive power of transforming plant main transformer depressor low-pressure side excision 20MVAR, generates idle coding " 1120 "; The second round AVC main website needs transformer station to keep current capacitive reactive power, generates instruction idle being encoded to " 1200 "; The transforming plant main transformer depressor low-pressure side that needs third round time AVC main website drops into the capacitive reactive power of 5MVAR, generates idle command coding and is " 2305 ";
For avoiding transmitting negative value, on-load tap-changing transformer control command separately is encoded to 4 integers, and each bit value defined declaration (is designated hereinafter simply as instruction separately) as follows:
Thousands digit value representation on-load tap-changing transformer is regulated direction separately, rises separately with " 1 " expression, falls separately with " 2 " expression, and other numerical value are thought disable instruction;
Hundred bit value represent that an instruction issues round, and numerical value increases progressively circulation from " 1 "-" 5 ", guarantee when sending instructions under the AVC main website is each that this bit value is different with last round instruction; If hundred bit value in the scope of " 1 "-" 5 ", are not thought disable instruction; The control command coding of going up round is preserved in AVC transformer station substation, obtain the control command coding of new round after, if find that hundred bit value of this control command coding are identical with last round numerical value, think this not renewal of round instruction;
Ten with the units value for rising separately or falling gear value separately, once at most only rise or fall 1 grade of parted hair, thus ten have only " 01 " perhaps " 00 " with an effective value of position, other numerical value are thought disable instruction.
For example, the first round AVC main website needs transformer station to fall one grade of on-load tap-changing transformer gear separately, and generating separately, command coding is " 2101 "; The second round AVC main website need keep transformer station's on-load tap-changing transformer gear separately, and generating separately, command coding is " 2200 "; Third round time AVC main website needs transformer station to rise one grade of on-load tap-changing transformer gear separately, and generating separately, command coding is " 1301 ";
3) the AVC main website sends idle instruction to AVC transformer station substation; And when transformer station is equipped with the Loading voltage regulator transformer and is set at adjustable gears; Send instruction separately through the different communication passage; AVC transformer station decodes according to the definition of coding numerical value after receiving the substation control command, carries out real-time regulated to transforming plant main transformer depressor low-pressure side is idle with the on-load tap-changing transformer gear according to decoded control command then; If surpassing, AVC transformer station substation do not receive that (routine was 15 minutes to the legal control command of having upgraded in 15 minutes; Also can set the longer or shorter time) according to actual conditions; Think that the AVC main website withdraws from; AVC transformer station substation automatically switches to local runtime, does not promptly accept AVC main website control command, controls according to AVC transformer station substation predetermined manner; If AVC transformer station substation is received the legal control command of having upgraded again, transfer automatically then that to receive AVC main website control command be distant place state of a control to;
For example, first round, idle regulating command " 1120 " is received the substation by AVC transformer station, regulating command " 2101 " separately, transforming plant main transformer depressor low-pressure side will be excised the capacitive reactive power of 20MVAR, and the on-load tap-changing transformer gear falls one grade; Idle instruction " 1200 " is received in the second round AVC transformer station substation, instruction " 2200 " separately, and transformer station keeps current capacitive reactive power, and the on-load voltage regulation transformation keeps current gear; Idle instruction " 2305 " is received in third round time AVC transformer station substation, instruction " 1301 " separately, and transforming plant main transformer depressor low-pressure side will drop into the capacitive reactive power of 5MVAR, and the on-load tap-changing transformer gear rises one grade; Four-wheel, idle instruction " 2305 " is received the substation by AVC transformer station, and instruction " 2301 " separately then judges that by hundred bit value drawing this instruction does not upgrade, and AVC transformer station is failure to actuate the substation.
Equally, if certain round receives that idle instruction is " 3315 ", kilobit numerical value is not " 1 " perhaps " 2 ", thinks that this idle instruction is a disable instruction.If certain round receives that idle instruction is " 1620 ", hundred bit value think that this idle instruction is a disable instruction not between " 1 "-" 5 ".If certain round receives that instruction separately is " 3101 ", kilobit numerical value is not " 1 " perhaps " 2 ", thinks that instruction is illegal.If certain round receives that separately instruction is " 1601 ", hundred bit value are thought that this instructs separately and are disable instruction not between " 1 "-" 5 ".If certain round receives that separately instruction is " 2502 ", ten is not " 01 " perhaps " 00 " with the units value, thinks that this instructs separately to be disable instruction.When receiving disable instruction, all be failure to actuate in AVC power transformation substation.
If AVC transformer station substation surpasses when not receiving the legal control command of having upgraded in 15 minutes; Think that the AVC main website withdraws from, AVC transformer station substation automatically switches to local runtime, does not promptly accept AVC main website control command; Control according to AVC transformer station substation predetermined manner; After for example transferring local runtime to, AVC transformer station substation control main transformer low-pressure side drops into the capacitive reactive power of 20MVAR, and the on-load tap-changing transformer gear remains unchanged.If AVC transformer station substation is received the legal control command of having upgraded again, for example receive idle instruction " 2420 ", separately instruction: " 2401 " are four-wheel time legal control command, transfer automatically then that to receive AVC main website control command be distant place state of a control to;
4) after AVC main website control command issues and finishes, wait for getting into the next round secondary voltage control cycle, change step 1).
Idle with No. 1 main transformer low-pressure side of A transformer station, the on-load tap-changing transformer gear, adopting the control command of four codings is embodiment, and the transformer station's automatic voltage control method based on the control command coding of the present invention is described, this method may further comprise the steps:
1) a secondary voltage control cycle begins; The AVC main website gathers the current throwing of transforming plant main transformer depressor low-pressure side reactive apparatus and moves back state and the current gear of transformer of carrying is arranged; Carry out transformer station's secondary voltage control and calculate, produce the capacitive reactive power that No. 1 main transformer low-pressure side of A transformer station need be excised 20MVAR.The current gear of on-load tap-changing transformer is " 1 ", and regulating target is " 2 " shelves, raises one grade.
2) the AVC main website generates transformer station's control command coding, generates idle command coding " 1X20 "; Generating separately, command coding is " 1X01 "; Hundred bit value are got " X ", represent the sequence number of this round.
3) the AVC main website sends idle instruction " 1X20 " and instruction " 1X01 " separately through different communication ports to AVC transformer station substation; AVC transformer station decodes according to the definition of coding numerical value after receiving the substation control command coding; Then according to decoding; No. 1 main transformer low-pressure side excision 20MVAR capacitive reactive power of the A of transformer station, the gear of on-load tap-changing transformer rises one grade.
4) after the instruction of AVC main website issues and finishes, wait for getting into the next round secondary voltage control cycle, change step 1).