CN202486269U - State tester of electrical equipment - Google Patents

State tester of electrical equipment Download PDF

Info

Publication number
CN202486269U
CN202486269U CN2012200077565U CN201220007756U CN202486269U CN 202486269 U CN202486269 U CN 202486269U CN 2012200077565 U CN2012200077565 U CN 2012200077565U CN 201220007756 U CN201220007756 U CN 201220007756U CN 202486269 U CN202486269 U CN 202486269U
Authority
CN
China
Prior art keywords
voltage
unit
scalable
electrical equipment
leakage
Prior art date
Application number
CN2012200077565U
Other languages
Chinese (zh)
Inventor
廖国斌
周建平
刘珧
刘俊岭
李中军
黄志刚
王武君
Original Assignee
宝山钢铁股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 宝山钢铁股份有限公司 filed Critical 宝山钢铁股份有限公司
Priority to CN2012200077565U priority Critical patent/CN202486269U/en
Application granted granted Critical
Publication of CN202486269U publication Critical patent/CN202486269U/en

Links

Abstract

The utility model brings forward a state tester of electrical equipment. The state tester of electrical equipment comprises an adjustable AC voltage forming unit, an adjustable DC voltage forming unit, a leakage voltage and current display unit, and a test connection unit. The adjustable AC voltage forming unit is connected to a three-phase AC power source to generate three-phase AC voltages for testing. The adjustable DC voltage forming unit is connected to the three-phase AC power source to generate DC voltages for testing. The leakage voltage and current display unit is connected to the three-phase AC power source and the adjustable DC voltage forming unit, and is used for detecting leakage voltages and leakage currents and displaying values of the leakage voltages and leakage currents. The test connection unit is connected to the adjustable AC voltage forming unit and the adjustable DC voltage forming unit. The test connection unit is also connected to to-be-tested electrical equipment. The test connection unit is used for testing the to-be-tested electrical equipment through utilization of the three-phase AC voltages and the DC voltages for testing.

Description

The state verification appearance of electrical equipment

Technical field

The utility model relates to electric detective technology, relates in particular to a kind of state verification appearance of electrical equipment.

Background technology

Pass in time, no matter whether electric equipment operation, all has the performance degradation problem.In order to hold electrical equipment (device) state, conventional means is that the function element of main circuit implementation cycle property, resistance, electric capacity, inductance etc. are taked offline mode to detect or tested, and its detection means is different according to the difference of components and parts.This means are very original, time-consuming takes manpower, needs enough stop times.Under the not enough situation of current human resources, seldom carried out the detection of off-line electrical equipment device and tested, just under the situation of haveing no alternative but, just implemented.Yet this means only reflect the device deterioration, do not reflect for the whole deterioration of device.So, need a kind of electrical equipment state verification appearance.

Electrical equipment be can deterioration mainly to show as performance low, catastrophic failure will very easily take place then.The deterioration of electrical equipment does not generally influence its equipment operate as normal in limits, in case the degradation value of overstepping the extreme limit will break down and paroxysmal often fault (accident).So the on-line tracing of equipment state exactly in order to hold the degradation trend of electrical equipment, thereby avoids equipment failure (accident) to take place.

Almost all can require product is carried out voltage-withstand test both at home and abroad to various security appliance standards.This just can find out that voltage-withstand test is an important component part of security appliance standard.The Hi-pot test (High Voltage Test) that voltage-withstand test (Dielectric Voltage Withstand Test) just is commonly called as is higher than the voltage of its ratings and keeps the whether satisfactory test of insulating material and space length that certain hour comes determining apparatus through equipment being applied one.

The domestic existing utilization of high voltage equipment insulation on-line monitoring system case to developing: the insulated on-line monitoring of high voltage electric equipment is a kind of safety test; Be (the earth) leakage current and leakage current testing (Leakage Current Test) over the ground; Leakage current in leakage current and the leakage current is identical at root, and all is the atomic little electric current that insulation system produces under the effect of voltage.Their difference is that the leakage current in the voltage-withstand test is under the situation of high pressure, to produce, and the leakage current in the leakage current testing produces under rated voltage.

The utility model content

The utility model proposes a kind of state verification appearance of electrical equipment, comprising: the scalable alternating voltage forms the unit, the scalable DC voltage forms unit, leakage voltage and current displaing unit and test linkage unit.

The scalable alternating voltage forms the unit and is connected to three-phase alternating-current supply, generates test and uses three-phase alternating voltage.The scalable DC voltage forms the unit and is connected to three-phase alternating-current supply, generates test and uses DC voltage.Leakage voltage and current displaing unit are connected to three-phase alternating-current supply and the scalable DC voltage forms the unit, detects leakage voltage and leakage current and shows leakage voltage and value of leakage current.The test linkage unit is connected to the scalable alternating voltage and forms unit and scalable DC voltage formation unit; The test linkage unit is also connected to electrical equipment to be measured, test linkage unit use test with three-phase alternating voltage with test with vdct electrical equipment to be measured.

In one embodiment; The scalable alternating voltage forms the unit and scalable DC voltage formation unit is connected to three-phase alternating-current supply through power contactor and three-phase from even pressure regulator; Power contactor connects three-phase alternating-current supply; Three-phase is connected with power contactor from even pressure regulator, and three-phase is connected to the scalable alternating voltage from even pressure regulator and forms unit and scalable DC voltage formation unit.

In one embodiment, scalable alternating voltage formation unit comprises boost isolating transformer and alternating voltage and electric current leakage display device.The isolating transformer that boosts is connected to three-phase from even pressure regulator.Alternating voltage and electric current leakage display device are connected to the isolating transformer that boosts.

In one embodiment, the scalable DC voltage form that the unit comprises that voltage transformation is opened, the uncontrollable rectifier of three-phase, leakage voltage and current sampling device and leakage voltage and current analog display device.The voltage transformation switch is connected to three-phase from even pressure regulator.The uncontrollable rectifier of three-phase is connected to the voltage transformation switch.Leakage voltage and current sampling device are connected to the uncontrollable rectifier of three-phase.Leakage voltage and current analog display device are connected to leakage voltage and current sampling device.

In one embodiment, leakage voltage and current displaing unit comprise control power transformer, control power indicator, test starting and stopping mechanism and numerical value display unit.The control power transformer is connected to three-phase alternating-current supply.The control power indicator is connected to the control power transformer.The test starting and stopping mechanism is connected to beginning and the end of control power indicator with the control test.The numerical value display unit is connected to the scalable DC voltage and forms the unit to show the numerical value of leakage voltage and electric current.

In one embodiment, the test linkage unit comprises fairing and inverter.Fairing is connected to the scalable alternating voltage and forms unit and electrical equipment to be measured, and test is carried out rectification and put on electrical equipment to be measured with three-phase alternating voltage.Inverter is connected to the scalable DC voltage and forms unit and electrical equipment to be measured, and test is carried out inversion and put on electrical equipment to be measured with DC voltage.

The state verification appearance of the electrical equipment of the utility model can be applied to power electronic equipment, the electric kinematic train of alternating current-direct current, RHVC, medium-high frequency supply unit, and the tracking and testing data are grasped the degradation trend of these electrical equipments.

Description of drawings

Fig. 1 has disclosed the structural drawing according to the state verification appearance of the electrical equipment of an embodiment of the utility model.

Fig. 2 has disclosed the physical circuit figure according to the state verification appearance of the electrical equipment of an embodiment of the utility model.

Fig. 3 has disclosed the physical circuit figure according to the state verification appearance of the electrical equipment of an embodiment of the utility model.

Embodiment

With reference to shown in Figure 1, the utility model has disclosed a kind of state verification appearance of electrical equipment, comprises that the scalable alternating voltage forms unit 102, the scalable DC voltage forms unit 104, leakage voltage and current displaing unit 106 and test linkage unit 108.

With reference to embodiment shown in Figure 1, the scalable alternating voltage forms unit 102 and is connected to three-phase alternating-current supply through power contactor 101 and three-phase from even pressure regulator 103 with scalable DC voltage formation unit 104.Wherein power contactor 101 directly connects three-phase alternating-current supply, and three-phase is connected with power contactor 101 from even pressure regulator 103, and three-phase is connected to the scalable alternating voltage from even pressure regulator 103 and forms unit 102 and scalable DC voltage formation unit 104.

The scalable alternating voltage forms unit 102 and is connected to three-phase alternating-current supply, generates test and uses three-phase alternating voltage.In the embodiment shown in fig. 1, the scalable alternating voltage forms unit 102 and is connected to three-phase alternating-current supply through power contactor 101 and three-phase from even pressure regulator 103.This scalable alternating voltage forms unit 102 and comprises boost isolating transformer 120 and alternating voltage and electric current leakage display device 122.The isolating transformer 120 that boosts is connected to three-phase from even pressure regulator 103.Alternating voltage and electric current leakage display device 122 are connected to the isolating transformer 120 that boosts.

The scalable DC voltage forms unit 104 and is connected to three-phase alternating-current supply, generates test and uses DC voltage.In the embodiment shown in fig. 1, the scalable DC voltage forms unit 104 and is connected to three-phase alternating-current supply through power contactor 101 and three-phase from even pressure regulator 103.This scalable DC voltage forms unit 104 and comprises the uncontrollable rectifier of voltage transformation switch 140, three-phase 142, leakage voltage and current sampling device 144 and leakage voltage and current analog display device 146.Voltage transformation switch 140 is connected to three-phase from even pressure regulator 103.The uncontrollable rectifier 142 of three-phase is connected to voltage transformation switch 140.Leakage voltage and current sampling device 144 are connected to the uncontrollable rectifier 142 of three-phase.Leakage voltage and current analog display device 146 are connected to leakage voltage and current sampling device 144.

Leakage voltage and current displaing unit 106 are connected to three-phase alternating-current supply and the scalable DC voltage forms unit 104, and leakage voltage and current displaing unit 106 detect leakage voltage and leakage current and show leakage voltage and value of leakage current.With reference to embodiment shown in Figure 1, leakage voltage and current displaing unit 106 comprise control power transformer 160, control power indicator 162, test starting and stopping mechanism 164 and numerical value display unit 166.Control power transformer 160 is connected to three-phase alternating-current supply.Control power indicator 162 is connected to control power transformer 160.Test starting and stopping mechanism 164 is connected to beginning and the end of control power indicator 162 with the control test.Numerical value display unit 166 is connected to the scalable DC voltage and forms unit 104 to show the numerical value of leakage voltage and electric current.

Test linkage unit 108 is connected to the scalable alternating voltage and forms unit 102 and scalable DC voltage formation unit 104, and test linkage unit 108 is also connected to electrical equipment to be measured 200.Test linkage unit 108 use tests with three-phase alternating voltage with test with vdct electrical equipment 200 to be measured.With reference to embodiment shown in Figure 1, this test linkage unit 108 comprises fairing 180 and inverter 182.Fairing 180 is connected to the scalable alternating voltage and forms unit 102 and electrical equipment 200 to be measured so that test is carried out rectification and put on electrical equipment to be measured 200 with three-phase alternating voltage.Inverter 182 is connected to the scalable DC voltage and forms unit 104 and electrical equipment 200 to be measured so that test is carried out inversion and put on electrical equipment to be measured 200 with DC voltage.

Fig. 2 and Fig. 3 are the physical circuit figure according to the state verification appearance of the electrical equipment of an embodiment of the utility model.Wherein Fig. 2 has disclosed the scalable alternating voltage and has formed unit, scalable DC voltage formation unit and test linkage unit circuit partly.Fig. 3 has disclosed the circuit of leakage voltage and current displaing unit part.

In conjunction with Fig. 2 and shown in Figure 3, the state verification appearance of the electrical equipment of the utility model utilization conventional electrical appliance equipment combination function is implemented electrical equipment is carried out state verification.This measuring technology characterizes its state deterioration condition based on leakage current characteristic after mainly bearing voltage based on electric components; And usually electric components has certain electric current and flows through when bearing rated voltage; What apply permission again surpasses voltage (the mains voltage maximum undulating quantity that desirable device can bear), sees that its electric current just can judge with situation of change whether this element well or not exists unusually.In addition, for for the first time can be as the original comparison foundation of unit state, and compare to analyze and just can very clearly know that whether device is in deterioration through after operation a period of time device being recorded data to the test data of device.Adopting the pressure regulator purpose is for the test of the electrical equipment device that satisfies different electric pressures, so just can apply in a flexible way in various electrical equipments.Adopting diode rectification to obtain DC voltage (pressure regulator is leaned in pressure regulation equally), is in order to satisfy the requirement of type electrical equipment state verifications such as picture continuous-current plant, ac-dc-ac inverter device equally.

In Fig. 2 and Fig. 3; Electrical equipment to be measured can be considered unknown quantity; After electrical equipment feeds normal volume voltage, under this rated voltage, always have an electric current (usually less than 1A) inflow device, distributed capacitance flows back to power supply through installing over the ground again; This electric current of inflow device just is referred to as leakage current (different with usually said leakage current) under the rated voltage bearing, and just can directly reflect the degradation of device internal electric components and parts performance according to this leakage current.

With reference to shown in Figure 2, the principle of work that the scalable alternating voltage forms the unit is following: T1 is an automatic coupling voltage regulator, and effect is to exchange (direct current) voltage range for the test that obtains broad.Automatic coupling voltage regulator T1 answers zero setting during use.Pressure regulator T2 rises and isolates and boosting, also is on-line testing appearance security needs.Contact K1-1 is the main contact head of main contactor K1, connects three-phase supply L1, L2, the L3 of tester.PV1 is the indication of test alternating voltage, and PV2 then is the DC voltage indication; PA1, PA2, PA3 show total leakage current (like power electronic devices SCR, IGBT, IGCT etc. and capacitor) of the alternating current of electric device to be tested." S " among Fig. 2 in the reometer loop is the insulation inserted block; So that show seal in (general PA1, PA2, three reometers of PA3 get final product with a table) of meter; When device fabrication was dispatched from the factory, when this equipment of giving added rated voltage, inflow device had a very little electric current (electric current below the ampere level); Because it is not high that device is gone up the electric current meter accuracy, can not reflect the following electric current of a peace.So, select for use the precision of reometer to want high here, can reflect the electric current below the ampere level; This electric current is defined as the prospective current of this power electronic equipment here; This prospective current with equipment operation year number increase, the device performance deterioration increases, so, just be referred to as leakage current to this prospective current that has changed; Yet, according to the situation of change of this leakage current just can easily grasp its power electronic equipment equipment state whether very.ETU, ETV, ETW are the three-phase p-wire pincers of tester, only need corresponding three-phase power input end that vises tested device during test.

Continue with reference to shown in Figure 2; The principle of work that the scalable DC voltage forms the unit is following: the effect of switch BN is the test specification that enlarges DC voltage; Make the application of instrument more flexible, it is high dc voltage output for low dc voltage output, switch BN cater to the right side that switch BN caters to the left side.U 1 is the uncontrollable rectifier bridge of three-phase full-wave, is mainly used in the generation DC voltage, and this voltage is typically connected to the inverter input end.RO is a current-limiting resistance, and R1, R2, R3, R4 are divider resistances, obtains DC voltage DCV as voltage sampling signal from R3, delivers to leakage voltage current values display unit and is shown by digital voltmeter.Obtain DC current DCA sampled signal from R5, here as the current detecting of little electric current (electric current below 1 ampere), this electric current shows and is shown by the digital electronic ammeter in the control circuit.PV2 is that the table meter of tester DC voltage shows, PA4 is the DC leakage current value when showing PV2 voltage, and the table meter to be considered in order meeting the needs of different users with the purpose that numeral shows, can to have been met the demands with digital demonstration usually.Whether very the state that this DC leakage current has reflected inverter and load, basic identical with exchanging the leakage current principle.XT is that test signal is held altogether; ET+, ET-are the vdct pincers of instrument output, can be used for flexibly and the connecting of tested power electronic equipment intermediate circuit (P, N).

In Fig. 2, comprise that also some auxiliary circuits: T3 is this instrument control power transformer, HL is a power light; SB1-2 is the test start button, and K1 is the primary power contactor, and KOC is the overcurrent protection contact; SB1-1 is that test stops key; U2 is that Control current is used the direct current rectifier bridge, and 7812 is stabilized voltage supply, obtains the numerical value display circuit that positive-negative power is supplied with DC leakage voltage and electric current respectively.

Fig. 3 has disclosed the principle of work of leakage voltage and current displaing unit.XT15 is that numeral shows that use synchronizing signal, fundamental purpose is exactly guarantee the voltage of leakage current value under corresponding with it synchronous.DCV, DCA are DC voltage sampled signal and the leakage current sampled signals that forms the unit from the scalable DC voltage, its digital display unit by operational amplifier, trigger, and voltage, the digital display tube of electric current and KOC overcurrent report to the police and form.

The state verification appearance of the electrical equipment of the utility model can be applied to power electronic equipment, the electric kinematic train of alternating current-direct current, RHVC, medium-high frequency supply unit, and the tracking and testing data are grasped the degradation trend of these electrical equipments.

Claims (6)

1. the state verification appearance of an electrical equipment is characterized in that, comprising:
The scalable alternating voltage forms the unit, is connected to three-phase alternating-current supply, generates test and uses three-phase alternating voltage;
The scalable DC voltage forms the unit, is connected to three-phase alternating-current supply, generates test and uses DC voltage;
Leakage voltage and current displaing unit are connected to three-phase alternating-current supply and scalable DC voltage and form the unit, detect leakage voltage and leakage current and show leakage voltage and value of leakage current;
The test linkage unit; Be connected to the scalable alternating voltage and form unit and scalable DC voltage formation unit; The test linkage unit is also connected to electrical equipment to be measured, the test linkage unit use said test with three-phase alternating voltage with test with the said electrical equipment to be measured of vdct.
2. the state verification appearance of electrical equipment as claimed in claim 1; It is characterized in that; Said scalable alternating voltage forms the unit and scalable DC voltage formation unit is connected to three-phase alternating-current supply through power contactor and three-phase from even pressure regulator; Said power contactor connects three-phase alternating-current supply, and three-phase is connected with power contactor from even pressure regulator, and three-phase is connected to the scalable alternating voltage from even pressure regulator and forms unit and scalable DC voltage formation unit.
3. the state verification appearance of electrical equipment as claimed in claim 2 is characterized in that, said scalable alternating voltage forms the unit and comprises:
The isolating transformer that boosts is connected to said three-phase from even pressure regulator;
Alternating voltage and electric current leakage display device are connected to the said isolating transformer that boosts.
4. the state verification appearance of electrical equipment as claimed in claim 2 is characterized in that, said scalable DC voltage forms the unit and comprises:
The voltage transformation switch is connected to said three-phase from even pressure regulator;
The uncontrollable rectifier of three-phase is connected to said voltage transformation switch;
Leakage voltage and current sampling device are connected to the uncontrollable rectifier of said three-phase;
Leakage voltage and current analog display device are connected to said leakage voltage and current sampling device.
5. the state verification appearance of electrical equipment as claimed in claim 1 is characterized in that, said leakage voltage and current displaing unit comprise:
The control power transformer is connected to three-phase alternating-current supply;
The control power indicator is connected to said control power transformer;
The test starting and stopping mechanism is connected to said control power indicator, the beginning and the end of control test;
The numerical value display unit is connected to said scalable DC voltage and forms the unit, shows the numerical value of leakage voltage and electric current.
6. the state verification appearance of electrical equipment as claimed in claim 1 is characterized in that, said test linkage unit comprises:
Fairing is connected to the scalable alternating voltage and forms unit and electrical equipment to be measured, and test is carried out rectification and put on electrical equipment to be measured with three-phase alternating voltage;
Inverter is connected to the scalable DC voltage and forms unit and electrical equipment to be measured, and test is carried out inversion and put on electrical equipment to be measured with DC voltage.
CN2012200077565U 2012-01-10 2012-01-10 State tester of electrical equipment CN202486269U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2012200077565U CN202486269U (en) 2012-01-10 2012-01-10 State tester of electrical equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2012200077565U CN202486269U (en) 2012-01-10 2012-01-10 State tester of electrical equipment

Publications (1)

Publication Number Publication Date
CN202486269U true CN202486269U (en) 2012-10-10

Family

ID=46960683

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2012200077565U CN202486269U (en) 2012-01-10 2012-01-10 State tester of electrical equipment

Country Status (1)

Country Link
CN (1) CN202486269U (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103412211A (en) * 2013-07-22 2013-11-27 淮南矿业(集团)有限责任公司 Rapid test device of small electrical equipment
CN105337508A (en) * 2015-11-14 2016-02-17 哈尔滨理工大学 Device for testing turn-to-turn insulation of electric reactor
CN105554212A (en) * 2015-12-03 2016-05-04 上海斐讯数据通信技术有限公司 Electric leakage detection method of mobile terminal and mobile terminal of electric leakage detection method
CN107037347A (en) * 2017-03-24 2017-08-11 宁波北仑国际集装箱码头有限公司 The power device measurement apparatus that a kind of ports handling machine is used
CN107101675A (en) * 2017-06-20 2017-08-29 宁波铭富汽车零部件有限公司 Starter motor electromagnetic switch detects streamline
CN107284966A (en) * 2017-06-20 2017-10-24 宁波铭富汽车零部件有限公司 A kind of automatic detection flow line

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103412211A (en) * 2013-07-22 2013-11-27 淮南矿业(集团)有限责任公司 Rapid test device of small electrical equipment
CN105337508A (en) * 2015-11-14 2016-02-17 哈尔滨理工大学 Device for testing turn-to-turn insulation of electric reactor
CN105554212A (en) * 2015-12-03 2016-05-04 上海斐讯数据通信技术有限公司 Electric leakage detection method of mobile terminal and mobile terminal of electric leakage detection method
CN105554212B (en) * 2015-12-03 2018-05-18 上海斐讯数据通信技术有限公司 A kind of mobile terminal of mobile terminal electrical leakage detecting method and electrical leakage detecting method
CN107037347A (en) * 2017-03-24 2017-08-11 宁波北仑国际集装箱码头有限公司 The power device measurement apparatus that a kind of ports handling machine is used
CN107101675A (en) * 2017-06-20 2017-08-29 宁波铭富汽车零部件有限公司 Starter motor electromagnetic switch detects streamline
CN107284966A (en) * 2017-06-20 2017-10-24 宁波铭富汽车零部件有限公司 A kind of automatic detection flow line

Similar Documents

Publication Publication Date Title
US9322866B2 (en) Method and apparatus for transformer diagnosis
Hui et al. Assessing utility harmonic impedance based on the covariance characteristic of random vectors
CN101571563B (en) Integrative electric energy quality monitoring terminal
EP3045930B1 (en) Testing system of gis electronic mutual inductor and method therefor
ES2346959T3 (en) Measurement devices.
US9389268B1 (en) System for locating a fault in a power distribution system comprising at least one DC voltage distributed resource having a controllable voltage source converter
Bollen Algorithms for characterizing measured three-phase unbalanced voltage dips
Hong et al. Winding condition assessment of power transformers based on vibration correlation
CN103698695B (en) The method of testing that a kind of multifunctional high pressure breaker electrical characteristic test device is performed
CN1892240B (en) On-line monitoring method for dissipative current value in leakage current of lightning protector
CN101788615B (en) Simple method for detecting phase sequence of three-phase industrial-frequency alternating current and detection device
ES2539185T3 (en) Diagnostic device of a DC link capacitor of an inverter
KR20070085378A (en) Leak current breaker and method
Dell'Aquila et al. New power-quality assessment criteria for supply systems under unbalanced and nonsinusoidal conditions
ES2533797T3 (en) Device and method for detecting a ground fault
WO2012059061A1 (en) Method and device for quality-monitoring of high-voltage electrical energy
CN204361912U (en) Motor drive
Chang et al. On tracking the source location of voltage sags and utility shunt capacitor switching transients
CN101470154B (en) Pressure-resistant test system
Muscas Power quality monitoring in modern electric distribution systems
CN102540001B (en) Method of checking alternating current loop of a 500kV transformer substation through carrying out simulated through-type three-phase short circuit
Wang et al. Calculation of the phase-angle-jump for voltage dips in three-phase systems
CN203490313U (en) PT secondary loop multi-point grounding alarming and positioning system
CN104677927A (en) Distribution transformer winding material detection system and method
CN103782509A (en) System for detecting internal winding faults of a synchronous generator, computer program product and method

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant