阅读说明：本技术 一种多状态变压器故障模拟系统 (Fault simulation system of multi-state transformer ) 是由 梁洛耕 施武生 陈三伟 杨柳林 梁伟新 黄宇 钱晓东 梁云芳 高磊 陈伟智 于 2020-04-30 设计创作，主要内容包括：本发明公开一种多状态变压器故障模拟系统,包括：模拟变压器,包括变压器本体和用于模拟变压器多状态故障的若干种变压器故障模拟模组；所述变压器故障模拟模组包括故障模拟装置和检测装置；上位机,用于建立并储存若干个变压器多状态故障模型和若干个模拟方案；所述一个模拟方案对应一个或多个变压器多状态故障模型；所述变压器多状态故障模型的参数可设定；PLC控制系统,用于获得模拟方案,依据模拟方案对应的变压器多状态故障模型控制模拟变压器进行变压器故障模拟；所述所有模拟变压器的电路部件都通过PLC总线连接PLC控制系统；所述上位机采用Windows操作系统的PC机。本发明最大限度模拟还原了变压器故障的真实情况,全面模拟变压器多种故障状态及其组合。(The invention discloses a multi-state transformer fault simulation system, which comprises: the simulation transformer comprises a transformer body and a plurality of transformer fault simulation modules for simulating multi-state faults of the transformer; the transformer fault simulation module comprises a fault simulation device and a detection device; the upper computer is used for establishing and storing a plurality of transformer multi-state fault models and a plurality of simulation schemes; the simulation scheme corresponds to one or more transformer multi-state fault models; the parameters of the transformer multi-state fault model can be set; the PLC control system is used for obtaining a simulation scheme and controlling the simulation transformer to carry out transformer fault simulation according to a transformer multi-state fault model corresponding to the simulation scheme; the circuit components of all the analog transformers are connected with a PLC control system through a PLC bus; the upper computer adopts a PC of a Windows operating system. The invention furthest simulates and restores the real condition of the transformer fault and comprehensively simulates various fault states and combinations of the transformer.)

1. A multi-state transformer fault simulation system, comprising:

the simulation transformer comprises a transformer body and a plurality of transformer fault simulation modules for simulating multi-state faults of the transformer; the transformer fault simulation module comprises a fault simulation device and a detection device;

the upper computer is used for establishing and storing a plurality of transformer multi-state fault models and a plurality of simulation schemes; the simulation scheme corresponds to one or more transformer multi-state fault models; the parameters of the transformer multi-state fault model can be set;

the PLC control system is used for obtaining a simulation scheme and controlling the simulation transformer to carry out transformer fault simulation according to a transformer multi-state fault model corresponding to the simulation scheme;

the circuit components of all the analog transformers are connected with a PLC control system through a PLC bus; the upper computer adopts a PC of a Windows operating system;

the transformer fault simulation module comprises a current simulation module for simulating a transformer current fault, a voltage simulation module for simulating a transformer voltage fault, a heating simulation module for simulating a transformer heating fault, a resistance simulation module for simulating a transformer resistance fault and an insulation damage simulation module for simulating transformer insulation damage;

the transformer body comprises a main circuit, a sleeve, a tap switch, a connector lug, an oil tank, a winding, an iron core clamp and a gas relay; the bushing comprises a high-voltage bushing and a low-voltage bushing;

the detection device comprises an ammeter, a voltmeter, a signal thermometer and an oil level indicator;

the transformer multi-state fault model comprises a transformer winding loop circuit equation, a transient field circuit coupling mathematical model, a winding hot spot temperature model, a transformer bushing radial temperature distribution equation, a transformer oil temperature model, a heat conductor temperature field model, a heat flux density equation, a transformer single-phase grounding model, a transformer short-circuit current model and a PWM current regulation model.

2. The multi-state transformer fault simulation system of claim 1, wherein: the fault simulation device of the current simulation module comprises two anti-parallel switching tubes, a switching tube driving plate connected with the switching tubes and a PWM signal generator connected with the switching tube driving plate; the current generated by the PWM signal generator is applied to a grounding wire of the simulation transformer iron core clamp; the detection devices of the current simulation module are connected in series.

3. The multi-state transformer fault simulation system of claim 1, wherein: the fault simulation device of the voltage simulation module is a voltage generator capable of outputting power frequency, 3-order, 5-order, 7-order and 9-order harmonic voltages with continuously adjustable amplitude of 0-200V.

4. The multi-state transformer fault simulation system of claim 1, wherein: the fault simulation device of the heating simulation module comprises a temperature control device; the temperature control device adopts temperature negative feedback closed loop PID control; the on-off control of the temperature control device adopts an electronic switch controlled by non-contact alternating-current voltage zero-crossing conduction; and the fault simulation device of the heating simulation module is dispersedly arranged in the sleeve, the connector lug, the oil tank and on the winding.

5. The multi-state transformer fault simulation system of claim 1, wherein: the resistance simulation module comprises an adjustable resistor; the adjustable resistor is connected with the tapping switch through an electric shock connection contactor; and the resistance simulation modules are connected to the lead-out wires of the windings of each phase in a dispersed manner.

6. A method of multi-state transformer fault simulation according to any of the above described transformer fault simulation systems of claims 1-5, comprising the steps of:

(1) selecting a simulation scheme on the upper computer or manually controlling the upper computer to start the PLC control system to directly jump to the step (3);

(2) inputting parameters on the upper computer;

(3) the PLC control system starts an analog transformer;

(4) the simulation transformer carries out fault simulation;

(5) when fault simulation is carried out, the PLC control system judges whether the simulation transformer meets set parameters; if not, returning to the step (3); if yes, continuing to carry out fault simulation;

(6) after the fault simulation is finished, the PLC control system transmits the data of the actual fault simulation back to the upper computer; the upper computer judges that the data of the actual fault simulation is compared with the data calculated by the transformer multi-state fault model, and if the comparison results are the same, the comparison is finished; and (4) if the comparison results are different, the upper computer corrects the actual fault simulation data, establishes a new model, stores the new model in the upper computer, and returns to the step (3) after the parameters are re-introduced into the PLC control system.

Technical Field

The invention relates to the technical field of operation and maintenance of transformers and power transformation, in particular to a multi-state transformer fault simulation system.

Background

The transformer is an indispensable electrical device in a power system, and is widely applied to links of transmission, distribution and use of electric energy of the power system. Therefore, the safe and stable operation of the power transformer plays an important role in the safe and reliable power supply of the whole power grid, and once the power transformer fails, a series of problems such as wide spread, high overhauling difficulty, long overhauling period, heavy economic loss and the like can be caused.

Common transformer failures are: iron core faults including local short circuit of the iron core, multipoint grounding of the iron core, magnetic saturation, discharge faults and the like; winding faults including winding turn-to-turn short circuit, winding phase-to-phase short circuit, winding ground short circuit, winding overheating, winding breakage and the like; major insulation faults including insulation breakdown, creeping discharge, oil flow electrification and the like; faults of the voltage-regulating tap switch body include oil leakage, poor sealing of the box body, unqualified direct-current resistance, burning loss of a contact and the like; lead faults including unqualified installation quality, untight lead connection, insufficient soldering and false soldering, lead overheating in the running process of the transformer, unqualified lead quality or partial breakage, insulation breakdown caused by damp insulation and the like; casing failures including casing flashover, casing overheating, pressure-equalizing ball suspension discharge, and the like; the structural part faults comprise oil leakage outside an oil tank, oil temperature rise of a strong oil air-cooled transformer, water in strong oil water-cooled transformer oil, misoperation of a gas relay and the like.

In a word, the transformer has various faults and complex mechanisms, and particularly, the electromagnetic change process of the internal fault is abstract, so that when the internal winding of the transformer has a fault, the change of the internal electrical quantity cannot be accurately estimated, and the correct action rate of the transformer protection is influenced. Therefore, the characteristics of the transformer when different faults occur are analyzed, and the state simulation is carried out, so that the method has important significance for the analysis of the faults of the transformer, the improvement and perfection of protective measures and the training of operation and maintenance personnel. The existing transformer fault simulation system is mainly based on computer simulation, cannot be determined by the complexity of transformer faults and the temperature distribution and change of an electromagnetic field, has a large difference between the modeling accuracy and the actual condition, is mainly limited to metal contact simulation by physical simulation, and hardly has temperature and current change simulation.

Disclosure of Invention

The invention aims to provide a multi-state transformer fault simulation system which can simulate and restore the real condition of transformer faults to the maximum extent and comprehensively simulate various fault states and combinations of the transformers.

To achieve the above object, there is provided a multi-state transformer fault simulation system, comprising:

the simulation transformer comprises a transformer body and a plurality of transformer fault simulation modules for simulating multi-state faults of the transformer; the transformer fault simulation module comprises a fault simulation device and a detection device;

the upper computer is used for establishing and storing a plurality of transformer multi-state fault models and a plurality of simulation schemes; the simulation scheme corresponds to one or more transformer multi-state fault models; the parameters of the transformer multi-state fault model can be set;

the PLC control system is used for obtaining a simulation scheme and controlling the simulation transformer to carry out transformer fault simulation according to a transformer multi-state fault model corresponding to the simulation scheme;

the circuit components of all the analog transformers are connected with a PLC control system through a PLC bus; the upper computer adopts a PC of a Windows operating system;

the transformer fault simulation module comprises a current simulation module for simulating a transformer current fault, a voltage simulation module for simulating a transformer voltage fault, a heating simulation module for simulating a transformer heating fault, a resistance simulation module for simulating a transformer resistance fault, an insulation damage simulation module for simulating transformer insulation damage and an oil level simulation module for simulating an oil level fault;

the transformer body comprises a main circuit, a sleeve, a tap switch, a connector lug, an oil tank, a winding, an iron core clamp and a gas relay; the bushing comprises a high-voltage bushing and a low-voltage bushing;

the detection device comprises an ammeter, a voltmeter, a signal thermometer and an oil level indicator;

the transformer multi-state fault model comprises a transformer winding loop circuit equation, a transient field circuit coupling mathematical model, a winding hot spot temperature model, a transformer bushing radial temperature distribution equation, a transformer oil temperature model, a heat conductor temperature field model, a heat flux density equation, a transformer single-phase grounding model, a transformer short-circuit current model and a PWM current regulation model.

Particularly, the fault simulation device of the current simulation module comprises two anti-parallel switching tubes, a switching tube driving plate connected with the switching tubes and a PWM signal generator connected with the switching tube driving plate; and the current generated by the PWM signal generator is applied to a grounding wire of the analog transformer core clamp.

Particularly, the fault simulation device of the voltage simulation module is a voltage generator capable of outputting power frequency, 3-order, 5-order, 7-order and 9-order harmonic voltages with continuously adjustable amplitude of 0-200V.

Particularly, the fault simulation device of the heating simulation module comprises a temperature control device; the temperature control device adopts temperature negative feedback closed loop PID control; the on-off control of the temperature control device adopts an electronic switch controlled by non-contact alternating-current voltage zero-crossing conduction; and the fault simulation device of the heating simulation module is dispersedly arranged in the sleeve, the connector lug, the oil tank and on the winding.

Particularly, the resistance simulation module comprises an adjustable resistor; the adjustable resistor is connected with the tapping switch through an electric shock connection contactor; and the resistance simulation modules are connected to the lead-out wires of the windings of each phase in a dispersed manner.

In particular, the oil level simulation module comprises a circulating oil pump.

A method for simulating the fault of a multi-state transformer according to the fault simulation system comprises the following steps:

(1) selecting a simulation scheme on the upper computer or manually controlling the upper computer to start the PLC control system to directly jump to the step (3);

(2) inputting parameters on the upper computer;

(3) the PLC control system starts an analog transformer;

(4) the simulation transformer carries out fault simulation;

(5) when fault simulation is carried out, the PLC control system judges whether the simulation transformer meets set parameters; if not, returning to the step (3); if yes, continuing to carry out fault simulation;

(6) after the fault simulation is finished, the PLC control system transmits the data of the actual fault simulation back to the upper computer; the upper computer judges that the data of the actual fault simulation is compared with the data calculated by the transformer multi-state fault model, and if the comparison results are the same, the comparison is finished; and (4) if the comparison results are different, the upper computer corrects the actual fault simulation data, establishes a new model, stores the new model in the upper computer, and returns to the step (3) after the parameters are re-introduced into the PLC control system.

The invention has the beneficial effects that:

the invention carries out fault simulation on the actual transformer through the upper computer and the PLC control system, adopts the combination of software and hardware, and furthest simulates and restores the real condition of the transformer fault. By means of the multi-state fault model of the transformer, comprehensive faults of the multi-state transformer can be analyzed, the model can be improved, an operation protection scheme according with actual conditions can be formulated according to simulation conditions, and multiple fault states and combinations of the transformer can be simulated comprehensively. The simulation technical support is provided for transformer operation, fault analysis, protection scheme determination and the like, and the simulation technical support can be used for training and researching scientific research personnel, transformer operation and maintenance technical personnel and students in electrical colleges and universities, and can be repeatedly researched at will and meet the training condition for practice.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic view of the overall structure of the present invention; wherein, (a) and (b) are the same transformer body, and (a) is the integral structure diagram of the transformer body; (b) is an internal structure diagram of the transformer body.

FIG. 2 is a flow chart of a method according to an embodiment of the present invention.

In the figure, ▲ is a mounting node of a heating simulation module, ★ is a mounting node of a current simulation module and a voltage simulation module, ● is a mounting node of a resistance simulation module,the installation node of the oil level simulation module is ◆ signal thermometers, 1 signal thermometer, 2 nameplate, 3 moisture absorber, 4 conservator, 5 oil level indicator, 6 explosion-proof tube, 7 gas relay, 8 high-voltage bushing, 9 low-voltage bushing, 10 tap switch, 11 heat-dissipation oil tube, 12 iron core, 13 winding, 14 oil drain valve, 15 guide rail, 16 ground terminal, 17 oil purifier, 18 transformer oil, 19 oil tank.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, and the scope of the present invention will be more clearly and clearly defined.

As shown in fig. 1, the multi-state transformer fault simulation system according to this embodiment includes a simulation transformer, an upper computer, and a PLC control system.

The simulation transformer comprises a transformer body and a plurality of transformer fault simulation modules for simulating multi-state faults of the transformer. The transformer fault simulation module comprises a fault simulation device and a detection device. The transformer body comprises a main circuit, a sleeve, a tap switch, a connector lug, an oil tank, a winding, an iron core clamp and a gas relay. The bushings include a high voltage bushing and a low voltage bushing. The detection device comprises an ammeter, a voltmeter, a signal thermometer and an oil level indicator.

And the upper computer is used for establishing and storing a plurality of transformer multi-state fault models and a plurality of simulation schemes. One simulation scheme corresponds to one or more transformer multi-state fault models. The parameters of the transformer multi-state fault model can be set.

And the PLC control system is used for obtaining the simulation scheme and controlling the simulation transformer to carry out transformer fault simulation according to the transformer multi-state fault model corresponding to the simulation scheme.

And all circuit components of the analog transformer are connected with the PLC control system through a PLC bus. The upper computer adopts a PC of a Windows operating system.

The transformer fault simulation module comprises a current simulation module for simulating a transformer current fault, a voltage simulation module for simulating a transformer voltage fault, a heating simulation module for simulating a transformer heating fault, a resistance simulation module for simulating a transformer resistance fault, an insulation damage simulation module for simulating transformer insulation damage and an oil level simulation module for simulating an oil level fault. The diagram of fig. 1 shows the positions where the transformer fault simulation modules are mounted on the transformer body.

The transformer multi-state fault model comprises a transformer winding loop circuit equation, a transient field circuit coupling mathematical model, a winding hot spot temperature model, a transformer bushing radial temperature distribution equation, a transformer oil temperature model, a heat conductor temperature field model, a heat flux density equation, a transformer single-phase grounding model, a transformer short-circuit current model and a PWM current regulation model:

transformer winding loop circuit equation:

transient field path coupling mathematical model:

winding hot spot temperature model:

radial temperature distribution equation of the transformer bushing:

the transformer oil temperature model:

heat conductor temperature field model:

heat flux density equation:

the single-phase grounding model of the transformer is as follows:

transformer short circuit current model:

PWM current regulation model:

the fault simulation device of the current simulation module comprises two anti-parallel switch tubes, a switch tube drive plate connected with the switch tubes and a PWM signal generator connected with the switch tube drive plate. The current generated by the PWM signal generator is applied to the grounding wire of the analog transformer core clamp. The PWM signal generator of the present embodiment has a continuous operation mode and an intermittent operation mode, i.e., a continuous output current and an intermittent output current, and the intermittent time can be arbitrarily adjusted by the PLC controller.

The fault simulation device of the voltage simulation module is a voltage generator capable of outputting power frequency, 3-order, 5-order, 7-order and 9-order harmonic voltages with continuously adjustable amplitude of 0-200V.

The fault simulation device of the heating simulation module comprises a temperature control device. The temperature control device adopts temperature negative feedback closed loop PID control. The on-off control of the temperature control device adopts an electronic switch controlled by non-contact alternating-current voltage zero-crossing conduction; . The fault simulation device of the heating simulation module is dispersedly arranged in the sleeve, the connector lug, the oil tank and on the winding. The temperature control device of the embodiment can be adjusted within the range of the current ambient temperature to 150 ℃.

The resistance simulation module comprises an adjustable resistor. The adjustable resistor is connected with the tapping switch through an electric shock connecting contactor. The resistance simulation module is connected to the lead-out wires of the windings of each phase in a dispersed manner.

The oil level simulation module comprises a circulating oil pump.

The simulation scheme of this embodiment, such as a simulation scheme for simulating a fault of a transformer core, may control a PWM signal generator of a current simulation module to generate a current with adjustable magnitude, time-varying control, and controllable current intensity and intermittent time to simulate a multipoint grounding and discharging fault of the transformer core; the simulation scheme of the transformer winding faults can simulate faults such as winding turn-to-turn short circuit, winding interphase short circuit, winding ground short circuit, winding overheating, winding disconnection and the like through the control of the resistance simulation module and the heating simulation module; the simulation scheme of the fault of the voltage-regulating tapping switch body simulates the faults of unqualified direct-current resistance, poor contact, contact burning loss and the like by controlling the voltage simulation module and the resistance simulation module and controlling the series connection of the adjustable resistance and changing the contact area and tightness of the adjustable resistance through variable difference; the heating simulation scheme of the sleeve adopts a heating simulation module to controllably heat and simulate the overheating phenomenon of the lead in the fault process of the lead; the PLC control system can also control detection devices such as a signal thermometer, a gas relay and an oil level indicator, and simulate the malfunction of instrument misoperation.

As shown in fig. 2, in this embodiment, (1) an analog scheme is selected on the upper computer or the upper computer is manually controlled to start the PLC control system and directly jump to step (3);

(2) inputting parameters on the upper computer;

(3) the PLC control system starts an analog transformer;

(4) the simulation transformer carries out fault simulation;

(5) when fault simulation is carried out, the PLC control system judges whether the simulation transformer meets set parameters; if not, returning to the step (3); if yes, continuing to carry out fault simulation;

(6) after the fault simulation is finished, the PLC control system transmits the data of the actual fault simulation back to the upper computer; the upper computer judges that the data of the actual fault simulation is compared with the data calculated by the transformer multi-state fault model, and if the comparison results are the same, the comparison is finished; and (4) if the comparison results are different, the upper computer corrects the actual fault simulation data, establishes a new model, stores the new model in the upper computer, and returns to the step (3) after the parameters are re-introduced into the PLC control system.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, various changes or modifications may be made by the patentees within the scope of the appended claims, and within the scope of the invention, as long as they do not exceed the scope of the invention described in the claims.