CN107783040A - A kind of modeling method of brush direct current motor electromagnetic interference, apparatus and system - Google Patents
A kind of modeling method of brush direct current motor electromagnetic interference, apparatus and system Download PDFInfo
- Publication number
- CN107783040A CN107783040A CN201710994520.2A CN201710994520A CN107783040A CN 107783040 A CN107783040 A CN 107783040A CN 201710994520 A CN201710994520 A CN 201710994520A CN 107783040 A CN107783040 A CN 107783040A
- Authority
- CN
- China
- Prior art keywords
- brush motor
- direct current
- model
- parameters
- electromagnetic interference
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000005259 measurement Methods 0.000 claims abstract description 63
- 239000011159 matrix material Substances 0.000 claims description 40
- 238000012545 processing Methods 0.000 claims description 11
- 238000013461 design Methods 0.000 abstract description 3
- 238000011161 development Methods 0.000 abstract description 2
- 238000012827 research and development Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 15
- 230000008569 process Effects 0.000 description 8
- 230000006870 function Effects 0.000 description 7
- 238000004364 calculation method Methods 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
- 239000004020 conductor Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000004891 communication Methods 0.000 description 3
- 238000005094 computer simulation Methods 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000004804 winding Methods 0.000 description 3
- 230000005672 electromagnetic field Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/34—Testing dynamo-electric machines
- G01R31/343—Testing dynamo-electric machines in operation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/0864—Measuring electromagnetic field characteristics characterised by constructional or functional features
- G01R29/0892—Details related to signal analysis or treatment; presenting results, e.g. displays; measuring specific signal features other than field strength, e.g. polarisation, field modes, phase, envelope, maximum value
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/30—Circuit design
- G06F30/36—Circuit design at the analogue level
- G06F30/367—Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- Electromagnetism (AREA)
- Control Of Direct Current Motors (AREA)
Abstract
This application provides a kind of modeling method of brush direct current motor electromagnetic interference, apparatus and system, method includes：Obtain target measurement data corresponding with the model parameter of equivalent-circuit model, equivalent-circuit model is the model established based on electromagnetic interference caused by brush direct current motor, and model parameter includes the current parameters of common mode admittance parameter, differential mode admittance parameter and current source；The model parameter of equivalent-circuit model is determined based on target measurement data, obtains model of the equivalent-circuit model with model parameter as brush direct current motor electromagnetic interference.The application provide modeling method it is simple, versatility is good, engineering practicability is strong, be advantageous to predict during designing and developing, analyze, improve Electro Magnetic Compatibility, improve efficiency of research and development, reduce development cost, and, the model of the electromagnetic interference of foundation can use as a component in the electric system-level EMC analysis comprising brush direct current motor, be favorably improved the efficiency of system-level EMC Design.
Description
Technical Field
The invention relates to the technical field of electromagnetic interference modeling, in particular to a modeling method, a device and a system for electromagnetic interference of a direct-current brush motor.
Background
A dc brush motor is a rotating electrical machine that includes a brush device and is capable of converting dc electrical energy into mechanical energy or converting mechanical energy into dc electrical energy. In contrast to dc brushless motors, brush devices are used to draw in or out dc voltages and dc currents. The DC brush motor is the basis of all motors, and has the characteristics of quick start, timely braking, capability of smoothly regulating the speed in a large range, relatively simple control circuit and the like.
However, the current change and spark caused by commutation when the dc brush motor works can cause significant electromagnetic interference, which makes the dc brush motor become an important electromagnetic interference source in the electronic and electrical system. International and national electromagnetic compatibility standards impose strict requirements on electromagnetic interference, and direct current brushed motors must meet the test standards of conducted emission and radiated emission. Therefore, it is very important to analyze the electromagnetic interference of the dc brush motor for product design.
Currently, a method for performing electromagnetic interference analysis on a dc brush motor includes: the method of empirical analysis and repeated test and the method of computer modeling simulation are the future development trend because the method of computer modeling simulation can predict the performance of electromagnetic interference in advance and save the cost and time of repeated test. The computer modeling method in the prior art generally obtains an approximate model according to the current waveform which is directly measured or roughly estimated and the basic parameters of a winding, is limited, is only suitable for partial motors, has no universality, needs a large amount of input of circuit diagrams, winding diagrams, device detailed parameters, structure digital analogy and the like in modeling, has any input deviation influencing the precision of the model, and has the disadvantages of complicated modeling process, longer period and lower engineering practicability.
Disclosure of Invention
In view of this, the present invention provides a modeling method, an apparatus and a system for electromagnetic interference of a dc brush motor, which are used to solve the problems that the modeling method in the prior art is limited, is only suitable for partial motors, has no universality, requires a large amount of inputs of circuit diagrams, winding diagrams, device detailed parameters, structural digital models, etc., any input deviation affects the accuracy of the model, the modeling process is complicated, the period is long, and the engineering practicability is low, and the technical scheme is as follows:
a modeling method for electromagnetic interference of a direct current brush motor comprises the following steps:
acquiring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common-mode interference and differential-mode interference, and the model parameters comprise common-mode admittance parameters, differential-mode admittance parameters and current parameters of a current source;
determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
The obtaining of target measurement data corresponding to model parameters of the equivalent circuit model includes:
obtaining a first scattering parameter matrix obtained by measuring a power input line of the direct current brush motor by a vector network analyzer;
obtaining voltage parameters obtained by measuring the direct current brush motor by voltage measuring equipment when the direct current brush motor generates interference current;
and obtaining a second scattering parameter matrix obtained by measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire by the vector network analyzer.
Wherein the determining model parameters of the equivalent circuit model based on the target measurement data comprises:
calculating the common mode admittance parameters and the differential mode admittance parameters through the first scattering parameter matrix;
and calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix, and calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measuring equipment.
Wherein, voltage measurement equipment measures the voltage parameter that DC brushed motor obtained when obtaining DC brushed motor produces interference current, include:
acquiring a first voltage of a power supply positive end of the direct current brush motor relative to a shielding layer of a first shielding wire and a second voltage of a power supply negative end of the direct current brush motor relative to a shielding layer of a second shielding wire, which are measured by the voltage measuring equipment;
wherein, the direct current has the power positive end of brush motor to pass through first shielded wire with power supply's power positive end is connected, the direct current has the power negative end of brush motor to pass through the second shielded wire with power supply's power negative end is connected, power supply sets up in the shielded box, the shielded box with the direct current has the brush motor all to set up on electrically conductive dull and stereotyped, the shielded box with electrically conductive dull and stereotyped electrical connection, the direct current have the electrically conductive shell of brush motor with electrically conductive dull and stereotyped electrical connection.
A modeling device for electromagnetic interference of a direct current brush motor comprises a measurement data acquisition module and a model parameter determination module;
the measurement data acquisition module is used for acquiring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common mode interference and differential mode interference, and the model parameters comprise common mode admittance parameters, differential mode admittance parameters and current parameters of a current source;
the model parameter determining module is used for determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
A modeling system for electromagnetic interference of a direct current brush motor comprises: a data processing device and a measuring device;
the measurement equipment is used for measuring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common mode interference and differential mode interference, and the model parameters comprise common mode admittance parameters, differential mode admittance parameters and current parameters of a current source;
the data processing device is used for obtaining the target measurement data from the measurement device, determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
Wherein the measuring device comprises: a vector network analyzer and a voltage measuring device;
the vector network analyzer is used for measuring a power input line of the direct current brush motor to obtain a first scattering parameter matrix;
the voltage measuring equipment is used for measuring voltage parameters when the direct current brush motor generates interference current;
the vector network analyzer is further used for measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire to obtain a second scattering parameter matrix.
The data processing device is specifically configured to calculate the common-mode admittance parameter and the differential-mode admittance parameter through the first scattering parameter matrix; and calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix, and calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measurement device.
The voltage measuring device is specifically configured to measure a first voltage of a positive power supply terminal of the dc brushed motor relative to a shielding layer of the first shielding line, and a second voltage of a negative power supply terminal of the dc brushed motor relative to a shielding layer of the second shielding line;
wherein, the direct current has the power positive terminal of brush motor to pass through first shielded wire is connected with power supply's power positive terminal, the direct current has the power negative terminal of brush motor to pass through the second shielded wire with power supply's power negative terminal is connected, power supply sets up in the shielded box, the shielded box with the direct current has the brush motor all to set up on electrically conductive dull and stereotyped, the shielded box with electrically conductive dull and stereotyped electrical connection, the direct current have brush motor electrically conductive shell with electrically conductive dull and stereotyped electrical connection.
The vector network analyzer has a direct current isolation function, and a shielding wire is directly connected to the vector network analyzer;
or,
the vector network analyzer has no function of isolating direct current, and the shielding wire is connected with a device for isolating direct current and then connected to the vector network analyzer.
The technical scheme has the following beneficial effects:
the modeling method, the modeling device and the modeling system for the electromagnetic interference of the direct current brush motor can obtain target measurement data corresponding to model parameters of an equivalent circuit model, determine the model parameters of the equivalent circuit model based on the target measurement data, and obtain the equivalent circuit model with the model parameters as the model for the electromagnetic interference of the direct current brush motor.
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 embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic flowchart of a modeling method for electromagnetic interference of a dc brush motor according to an embodiment of the present invention;
fig. 2 is a schematic diagram of a dc brush motor and an equivalent circuit model established based on electromagnetic interference generated by the dc brush motor according to an embodiment of the present invention;
fig. 3 is a schematic flow chart of an implementation process of determining a common mode admittance parameter and a differential mode admittance parameter of an equivalent circuit model in the modeling method for electromagnetic interference of a dc brushed motor according to the embodiment of the present invention;
fig. 4 is a schematic diagram of a power input line of a dc brush motor measured by a vector network analyzer in a modeling method of electromagnetic interference of the dc brush motor according to an embodiment of the present invention;
fig. 5 is a schematic flowchart of an implementation process of determining a current parameter of a current source of an equivalent circuit model in the modeling method of electromagnetic interference of a dc brush motor according to the embodiment of the present invention;
FIG. 6 is a schematic diagram of a voltage parameter measurement arrangement of a current source according to an embodiment of the present invention;
FIG. 7 is a schematic diagram of an equivalent circuit of a voltage parameter measurement arrangement of a current source according to an embodiment of the present invention;
FIG. 8 is a schematic view of a measurement setup of the shielded wires and the power supply in an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a modeling apparatus for electromagnetic interference of a dc brush motor according to an embodiment of the present invention;
fig. 10 is a schematic structural diagram of a modeling system for electromagnetic interference of a dc brush motor according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the present invention provides a modeling method for electromagnetic interference of a dc brush motor, please refer to fig. 1, which shows a flow diagram of the modeling method, and may include:
step S101: and acquiring target measurement data corresponding to the model parameters of the equivalent circuit model.
The equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common mode interference and differential mode interference, the common mode interference is interference of positive and negative ends of a power supply of the direct-current brush motor relative to the conductive shell, and the differential mode interference is interference generated between the positive and negative ends of the power supply of the direct-current brush motor. Since the interference sources include source impedance/source admittance, source current/source voltage, the present embodiment utilizes differential mode admittance, common mode admittance and current sources to characterize common mode interference and differential mode interference. Referring to fig. 2, a schematic diagram (a) of the dc brush motor and a schematic diagram (b) of an equivalent circuit model established based on electromagnetic interference generated by the dc brush motor are shown.
Step S102: and determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct-current brush motor.
Wherein the model parameters include a common-mode admittance parameter YCM+And YCM-Differential mode admittance parameter YDMAnd the current parameters I + and I-of the current source.
The modeling method of the electromagnetic interference of the direct-current brush motor provided by the embodiment of the invention can obtain the target measurement data corresponding to the model parameters of the equivalent circuit model, and further determine the model parameters of the equivalent circuit model based on the target measurement data, so that the model of the electromagnetic interference of the direct-current brush motor is obtained.
Referring to fig. 3, a schematic flow chart of an implementation process of obtaining target measurement parameters corresponding to a common-mode admittance parameter and a differential-mode admittance parameter in the modeling method for electromagnetic interference of a dc brushed motor according to the foregoing embodiment and determining the common-mode admittance parameter and the differential-mode admittance parameter of an equivalent circuit model based on the target measurement parameters is shown, and the implementation process may include:
step S301: and acquiring a first scattering parameter matrix obtained by measuring a power input line of the direct current brush motor by the vector network analyzer.
In this embodiment, a power input line of the dc brush motor may be measured by a vector network analyzer to obtain a first scattering parameter matrix, i.e., an S parameter matrix. The vector network analyzer can measure the amplitude and the phase of the scattering parameter of a single-port network or a two-port network.
Specifically, as shown in fig. 4, the positive power supply end and the conductive shell of the dc brush motor are respectively connected to the inner core and the outer conductor at one end of one coaxial cable, the negative power supply end and the conductive shell are respectively connected to the inner core and the outer conductor at one end of the other coaxial cable, and the other ends of the two coaxial cables are respectively connected to the first port and the second port of the vector network analyzer.
The S-parameter matrix measured by the vector network analyzer can be expressed as:
wherein S is11、S12、S21、S22Are complex numbers that include both amplitude and phase. It should be noted that the scattering parameter is an important parameter in microwave transmission, and for the case that the first port is a transmitting port and the second port is a receiving port, S is12For reverse transmission coefficients, i.e. isolation, S21For the forward transmission coefficient, i.e. gain, S11For input reflection coefficient, i.e. input return loss, S22To output the reflection coefficient, i.e. the output return loss.
Step S302: common mode admittance parameters and differential mode admittance parameters are calculated based on the first scattering parameter matrix.
After obtaining the scattering parameter matrix, the common mode admittance parameter and the differential mode admittance parameter can be calculated through the scattering parameter matrix, specifically, the common mode admittance parameter and the differential mode admittance parameter are calculated through the scattering parameter matrix by using the following formula (1) and formula (2):
wherein,as a scattering parameter matrix, YrThe matching resistor is used for connecting a vector network analyzer and a coaxial cable of a direct current brush motor with the vector network analyzer. For a common 50 ohm system, Yr is 0.02.
Referring to fig. 5, an implementation process of obtaining a target measurement parameter corresponding to a current parameter of a current source and determining the current parameter of the current source of an equivalent circuit model based on the target measurement parameter is shown, where the process may include:
step S501: and obtaining voltage parameters obtained by measuring the direct current brush motor by the voltage measuring equipment when the direct current brush motor generates interference current.
In this embodiment, the positive power terminal of the dc brush motor is connected to the positive power terminal of the power supply through the first shielding wire, the negative power terminal of the dc brush motor is connected to the negative power terminal of the power supply through the second shielding wire, the power supply is disposed in the shielding box, the shielding box and the dc brush motor are both disposed on the conductive plate, the shielding box is electrically connected to the conductive plate, and the conductive housing of the dc brush motor is electrically connected to the conductive plate, as shown in fig. 6. It should be noted that, the direct current brush motor and the power supply are connected by the shielding wire and the conductive flat plate, so as to ensure that the power supply, such as the storage battery, the current transmission path, i.e. the wire harness, and the interference source, i.e. the direct current brush motor, are at the equipotential, and at the same time ensure that the interference current flows inside the shielding system, and is not emitted in the form of electromagnetic waves to cause energy reduction.
After the connection arrangement, a first voltage of the positive power supply terminal of the dc brush motor relative to the shielding layer of the first shielding wire and a second voltage of the negative power supply terminal of the dc brush motor relative to the shielding layer of the second shielding wire are measured by a voltage measuring device such as a voltage probe, and an equivalent circuit is shown in fig. 7, Y in fig. 7bFor shielding lines and admittance of power supply, YpIs the admittance of the voltage measuring device, which is a known fixed value given by the manufacturer of the voltage measuring device.
Step S502: and obtaining a second scattering parameter matrix obtained by measuring the shielding wire connected with the vector network analyzer and the power supply connected with the shielding wire by the vector network analyzer, and calculating the admittance of the shielding wire and the power supply based on the second scattering parameter matrix.
When the vector network analyzer is used for measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire, the positive end of the power supply is connected with the first port of the vector network analyzer, and the negative end of the power supply is connected with the second port of the vector network analyzer, as shown in fig. 8, it should be noted that when the shielding wire and the power supply are measured, the vector network analyzer needs to have a function of isolating direct current, because the vector network analyzer may be burnt out if the direct current is not isolated, and if the vector network analyzer does not have the function of isolating direct current, the shielding wire can be connected with a device for isolating direct current, and then the device is connected with the vector network analyzer.
The second scattering parameter matrix, i.e. the S parameter matrix, measured by the vector network analyzer can be expressed as:
wherein S isb11、Sb12、Sb21、Sb22Are complex numbers that include both amplitude and phase.
Obtaining a second scattering parameter matrix SbThereafter, the scattering matrix S can be passedbThe admittance of the shielded wire and the power supply is calculated using equations (3) and (4):
where Yr is the matching resistance of the coaxial line and the vector network analyzer such as the vector network analyzer, and for a common 50 ohm system, Yr is 0.02.
Step S503: and calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measuring equipment.
Specifically, the current parameter of the current source is calculated by using formula (5) through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding line and the power supply and the admittance of the voltage measuring device:
wherein Y is an admittance matrix of the DC brush motor composed of common mode admittance parameters and differential mode admittance parameters, and Y isbFor shielding lines and admittance of power supply, YpFor admittance of voltage measuring devices, V+Is a first voltage, V-Is a second voltage, I+And I-Is a current parameter of the current source.
After the equivalent circuit model is constructed and the model parameters of the equivalent circuit model are determined, the model of the electromagnetic interference of the direct current brush motor is obtained, and the model can be used in circuit simulation software such as pSpice or electromagnetic field simulation software such as CST. The method has the advantages that the equivalent circuit model and the model parameters of the equivalent circuit model are added to simulation software, so that the electromagnetic interference characteristic of the direct-current brush motor can be simulated, conducted emission and radiated emission required by an electromagnetic compatibility test standard are predicted, the conducted emission generally needs to calculate the voltage or current of a power supply end, the radiated emission generally needs to calculate an electromagnetic field at a certain distance, the electromagnetic interference model provided by the invention can be completed under the simulation software as long as the electromagnetic interference model is established, the model can also be used as an assembly in the electronic and electrical system-level electromagnetic compatibility analysis including the direct-current brush motor, and the efficiency of system-level electromagnetic compatibility design is improved.
Corresponding to the above method, an embodiment of the present invention further provides a modeling apparatus for electromagnetic interference of a dc brush motor, please refer to fig. 9, which shows a schematic structural diagram of the modeling apparatus, and the modeling apparatus may include a measurement data obtaining module 901 and a model parameter determining module 902.
The measurement data obtaining module 901 is configured to obtain target measurement data corresponding to a model parameter of an equivalent circuit model, where the equivalent circuit model is a model established based on electromagnetic interference generated by a dc brush motor, the electromagnetic interference generated by the dc brush motor includes common mode interference and differential mode interference, and the model parameter includes a common mode admittance parameter, a differential mode admittance parameter, and a current parameter of a current source.
And a model parameter determining module 902, configured to determine a model parameter of the equivalent circuit model based on the target measurement data, and obtain the equivalent circuit model with the model parameter as a model of electromagnetic interference of the dc brush motor.
The modeling device for the electromagnetic interference of the direct-current brush motor, provided by the embodiment of the invention, can obtain target measurement data corresponding to the model parameters of the equivalent circuit model, and further determine the model parameters of the equivalent circuit model based on the target measurement data, so that the model for the electromagnetic interference of the direct-current brush motor is obtained.
In the modeling apparatus provided in the above embodiment, the measurement data obtaining module 901 may include: a first acquisition submodule, a second acquisition submodule and a third acquisition submodule.
The first acquisition submodule is used for acquiring a first scattering parameter matrix obtained by measuring a power input line of the direct-current brush motor by the vector network analyzer.
And the second acquisition submodule is used for acquiring voltage parameters obtained by measuring the direct current brushed motor by the voltage measuring equipment when the direct current brushed motor generates interference current.
And the third acquisition submodule is used for acquiring a second scattering parameter matrix obtained by the vector network analyzer measuring a shielding wire connected with the second acquisition submodule and a power supply connected with the shielding wire.
Further, the second obtaining submodule is specifically configured to obtain a first voltage, measured by the voltage measuring device, of a positive power supply terminal of the dc brushed motor relative to the shielding layer of the first shielding line, and a second voltage, measured by the voltage measuring device, of a negative power supply terminal of the dc brushed motor relative to the shielding layer of the second shielding line.
The power supply positive end of the direct current brush motor is connected with the power supply positive end of the power supply through the first shielding wire, the power supply negative end of the direct current brush motor is connected with the power supply negative end of the power supply through the second shielding wire, the power supply is arranged in the shielding box, the shielding box and the direct current brush motor are both arranged on the conductive flat plate, the shielding box is electrically connected with the conductive flat plate, and the conductive shell of the direct current brush motor is electrically connected with the conductive flat plate.
In the modeling apparatus provided in the above-described embodiment, the model parameter determination module includes: the device comprises a first calculation submodule, a second calculation submodule and a third calculation submodule.
And the first calculation submodule is used for calculating the common mode admittance parameters and the differential mode admittance parameters through the first scattering parameter matrix.
And the second calculation submodule is used for calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix.
And the third calculation submodule is used for calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measurement equipment.
The embodiment of the present invention further provides a modeling system for electromagnetic interference of a dc brush motor, please refer to fig. 10, which shows a schematic structural diagram of the system, and may include: a data processing device 1001 and a measuring device 1002.
The measurement device 1002 is configured to measure target measurement data corresponding to a model parameter of an equivalent circuit model, where the equivalent circuit model is a model established based on electromagnetic interference generated by a dc brush motor, the electromagnetic interference generated by the dc brush motor includes common mode interference and differential mode interference, and the model parameter includes a common mode admittance parameter, a differential mode admittance parameter, and a current parameter of a current source.
And the data processing device 1001 is used for acquiring target measurement data from the measurement device, determining model parameters of the equivalent circuit model based on the target measurement data, and acquiring the equivalent circuit model with the model parameters as a model of electromagnetic interference of the direct-current brush motor.
According to the modeling system for the electromagnetic interference of the direct-current brush motor, the measuring equipment can measure target measurement data corresponding to the model parameters of the equivalent circuit model, the data processing equipment can determine the model parameters of the equivalent circuit model based on the target measurement data, and therefore the model for the electromagnetic interference of the direct-current brush motor can be obtained.
In the system provided in the foregoing embodiment, the measurement device 1002 may include: vector network analyzer and voltage measuring device.
And the vector network analyzer is used for measuring a power input line of the direct current brush motor to obtain a first scattering parameter matrix.
When measurement is performed, as shown in fig. 4, the positive power supply end and the conductive shell of the dc brush motor are respectively connected to the inner core and the outer conductor at one end of one coaxial cable, the negative power supply end and the conductive shell are respectively connected to the inner core and the outer conductor at one end of the other coaxial cable, and the other ends of the two coaxial cables are respectively connected to the first port and the second port of the vector network analyzer.
And the voltage measuring equipment is used for measuring voltage parameters when the direct current brush motor generates interference current.
Further, the voltage measuring device measures a first voltage of the positive power supply terminal of the dc brushed motor with respect to the shielding layer of the first shielding wire, and a second voltage of the negative power supply terminal of the dc brushed motor with respect to the shielding layer of the second shielding wire. The power supply positive end of the direct current brush motor is connected with the power supply positive end of the power supply through the first shielding wire, the power supply negative end of the direct current brush motor is connected with the power supply negative end of the power supply through the second shielding wire, the power supply is arranged in the shielding box, the shielding box and the direct current brush motor are both arranged on the conductive flat plate, the shielding box is electrically connected with the conductive flat plate, and the conductive shell of the direct current brush motor is electrically connected with the conductive flat plate. It should be noted that, the direct current brush motor and the power supply are connected by the shielding wire and the conductive flat plate, so as to ensure that the power supply, such as the storage battery, the current transmission path, i.e. the wire harness, and the interference source, i.e. the direct current brush motor, are at the equipotential, and at the same time ensure that the interference current flows inside the shielding system, and is not emitted in the form of electromagnetic waves to cause energy reduction.
And the vector network analyzer is also used for measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire to obtain a second scattering parameter matrix.
When the vector network analyzer is used to measure the shielded wire and the power supply, the positive terminal of the power supply is connected to the first port of the vector network analyzer, and the negative terminal of the power supply is connected to the second port of the vector network analyzer, as shown in fig. 8. It should be noted that, when the shielded line and the power supply are measured, the vector network analyzer needs to have a function of isolating direct current, and if the vector network analyzer does not have the function of isolating direct current, the shielded line may be connected to a device for isolating direct current first, and then the device is connected to the vector network analyzer.
After obtaining the data measured by the measurement device, the data processing device 1001 calculates model parameters of the equivalent circuit model based on the data, specifically, calculates common mode admittance parameters and differential mode admittance parameters through the first scattering parameter matrix; and calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix, and calculating the current parameter of the current source through the common-mode admittance parameter, the differential-mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measuring equipment.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.
In the several embodiments provided in the present application, it should be understood that the disclosed method, apparatus, and device may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of devices or units through some communication interfaces, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment. In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. A modeling method for electromagnetic interference of a direct current brush motor is characterized by comprising the following steps:
acquiring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common-mode interference and differential-mode interference, and the model parameters comprise common-mode admittance parameters, differential-mode admittance parameters and current parameters of a current source;
determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
2. The modeling method of electromagnetic interference of a direct current brush motor according to claim 1, wherein the obtaining of target measurement data corresponding to model parameters of an equivalent circuit model comprises:
obtaining a first scattering parameter matrix obtained by measuring a power input line of the direct current brush motor by a vector network analyzer;
obtaining voltage parameters obtained by measuring the direct current brush motor by voltage measuring equipment when the direct current brush motor generates interference current;
and obtaining a second scattering parameter matrix obtained by measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire by the vector network analyzer.
3. The modeling method of electromagnetic interference of a direct current brush motor according to claim 2, wherein the determining model parameters of the equivalent circuit model based on the target measurement data comprises:
calculating the common mode admittance parameters and the differential mode admittance parameters through the first scattering parameter matrix;
and calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix, and calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measuring equipment.
4. The modeling method for electromagnetic interference of the direct current brush motor according to claim 2, wherein the obtaining of the voltage parameter obtained by measuring the direct current brush motor by the voltage measuring device when the direct current brush motor generates the interference current comprises:
acquiring a first voltage of a power supply positive end of the direct current brush motor relative to a shielding layer of a first shielding wire and a second voltage of a power supply negative end of the direct current brush motor relative to a shielding layer of a second shielding wire, which are measured by the voltage measuring equipment;
wherein, the direct current has the power positive end of brush motor to pass through first shielded wire with power supply's power positive end is connected, the direct current has the power negative end of brush motor to pass through the second shielded wire with power supply's power negative end is connected, power supply sets up in the shielded box, the shielded box with the direct current has the brush motor all to set up on electrically conductive dull and stereotyped, the shielded box with electrically conductive dull and stereotyped electrical connection, the direct current have the electrically conductive shell of brush motor with electrically conductive dull and stereotyped electrical connection.
5. A modeling device for electromagnetic interference of a direct current brush motor is characterized by comprising a measurement data acquisition module and a model parameter determination module;
the measurement data acquisition module is used for acquiring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common mode interference and differential mode interference, and the model parameters comprise common mode admittance parameters, differential mode admittance parameters and current parameters of a current source;
the model parameter determining module is used for determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
6. A modeling system for electromagnetic interference of a direct current brush motor is characterized by comprising: a data processing device and a measuring device;
the measurement equipment is used for measuring target measurement data corresponding to model parameters of an equivalent circuit model, wherein the equivalent circuit model is a model established based on electromagnetic interference generated by the direct-current brush motor, the electromagnetic interference generated by the direct-current brush motor comprises common mode interference and differential mode interference, and the model parameters comprise common mode admittance parameters, differential mode admittance parameters and current parameters of a current source;
the data processing device is used for obtaining the target measurement data from the measurement device, determining model parameters of the equivalent circuit model based on the target measurement data, and obtaining the equivalent circuit model with the model parameters as a model of the electromagnetic interference of the direct current brush motor.
7. The modeling system of claim 6, wherein the measurement device comprises: a vector network analyzer and a voltage measuring device;
the vector network analyzer is used for measuring a power input line of the direct current brush motor to obtain a first scattering parameter matrix;
the voltage measuring equipment is used for measuring voltage parameters when the direct current brush motor generates interference current;
the vector network analyzer is further used for measuring a shielding wire connected with the vector network analyzer and a power supply connected with the shielding wire to obtain a second scattering parameter matrix.
8. The modeling system of claim 7, wherein the data processing device is specifically configured to calculate the common mode admittance parameters and the differential mode admittance parameters from the first scattering parameter matrix; and calculating the admittance of the shielding wire and the power supply through the second scattering parameter matrix, and calculating the current parameter of the current source through the common mode admittance parameter, the differential mode admittance parameter, the voltage parameter, the admittance of the shielding wire and the power supply and the admittance of the voltage measurement device.
9. The modeling system of claim 7, wherein the voltage measuring device is specifically configured to measure a first voltage of a positive power supply terminal of the dc brushed motor with respect to a shield of a first shield wire and a second voltage of a negative power supply terminal of the dc brushed motor with respect to a shield of a second shield wire;
wherein, the direct current has the power positive terminal of brush motor to pass through first shielded wire is connected with power supply's power positive terminal, the direct current has the power negative terminal of brush motor to pass through the second shielded wire with power supply's power negative terminal is connected, power supply sets up in the shielded box, the shielded box with the direct current has the brush motor all to set up on electrically conductive dull and stereotyped, the shielded box with electrically conductive dull and stereotyped electrical connection, the direct current have brush motor electrically conductive shell with electrically conductive dull and stereotyped electrical connection.
10. The modeling system of claim 7, wherein the vector network analyzer has a function of isolating direct current, and a shielded wire is directly connected to the vector network analyzer;
or,
the vector network analyzer has no function of isolating direct current, and the shielding wire is connected with a device for isolating direct current and then connected to the vector network analyzer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710994520.2A CN107783040B (en) | 2017-10-23 | 2017-10-23 | Modeling method, device and system for electromagnetic interference of direct-current brush motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710994520.2A CN107783040B (en) | 2017-10-23 | 2017-10-23 | Modeling method, device and system for electromagnetic interference of direct-current brush motor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107783040A true CN107783040A (en) | 2018-03-09 |
| CN107783040B CN107783040B (en) | 2020-06-05 |
Family
ID=61433889
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710994520.2A Active CN107783040B (en) | 2017-10-23 | 2017-10-23 | Modeling method, device and system for electromagnetic interference of direct-current brush motor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107783040B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111025038A (en) * | 2019-08-28 | 2020-04-17 | 湖南大学 | Prediction method and system for radiation electromagnetic interference of electric drive system |
| EP3786650A1 (en) * | 2019-08-27 | 2021-03-03 | Robert Bosch GmbH | Method and device for providing a behaviour model for simulating electromagnetic interference emissions of an electrical or electronic component |
| DE102019212783A1 (en) * | 2019-08-27 | 2021-03-04 | Robert Bosch Gmbh | Method and device for providing a behavior model for the simulation of electromagnetic interference emissions from an electrical or electronic component |
| CN113311238A (en) * | 2021-07-09 | 2021-08-27 | 福州大学 | Method for measuring impedance between cables by using two ports |
| CN113378358A (en) * | 2021-05-20 | 2021-09-10 | 同济大学 | Modeling simulation method for conduction and radiation interference of direct-current brush motor |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101901286A (en) * | 2010-07-09 | 2010-12-01 | 北京航空航天大学 | Modeling method for leading cable and chassis to be equivalent to interference sources under complex electromagnetic environment |
| CN103543348A (en) * | 2012-07-16 | 2014-01-29 | 曾彧婕 | Electromagnetic compatibility detection method of new energy automobile |
| CN104698860A (en) * | 2015-02-05 | 2015-06-10 | 北京理工大学 | Conduction electromagnetic interference simulation system for alternating-current motor inverter power circuit of electric car |
| CN105071723A (en) * | 2015-06-16 | 2015-11-18 | 吉林大学 | Brushed direct current motor compound control method design by three-step approach |
| CN105354397A (en) * | 2015-12-08 | 2016-02-24 | 中国科学院电工研究所 | Design method for common-mode electro-magnetic interference filter for motor drive system |
| JP2017062170A (en) * | 2015-09-25 | 2017-03-30 | 株式会社日立製作所 | Rotary machine diagnostic system |
| CN106569406A (en) * | 2016-11-07 | 2017-04-19 | 华侨大学 | Brush DC motor model parameter quick identification method based on scale transform |
| US20170184640A1 (en) * | 2014-09-12 | 2017-06-29 | Carnegie Mellon University | Systems, Methods, and Software for Planning, Simulating, and Operating Electrical Power Systems |
| CN106991263A (en) * | 2017-05-25 | 2017-07-28 | 清华大学 | A kind of modeling method of mesolow distribution transformer winding thunder and lightning wideband model |
-
2017
- 2017-10-23 CN CN201710994520.2A patent/CN107783040B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101901286A (en) * | 2010-07-09 | 2010-12-01 | 北京航空航天大学 | Modeling method for leading cable and chassis to be equivalent to interference sources under complex electromagnetic environment |
| CN103543348A (en) * | 2012-07-16 | 2014-01-29 | 曾彧婕 | Electromagnetic compatibility detection method of new energy automobile |
| US20170184640A1 (en) * | 2014-09-12 | 2017-06-29 | Carnegie Mellon University | Systems, Methods, and Software for Planning, Simulating, and Operating Electrical Power Systems |
| CN104698860A (en) * | 2015-02-05 | 2015-06-10 | 北京理工大学 | Conduction electromagnetic interference simulation system for alternating-current motor inverter power circuit of electric car |
| CN105071723A (en) * | 2015-06-16 | 2015-11-18 | 吉林大学 | Brushed direct current motor compound control method design by three-step approach |
| JP2017062170A (en) * | 2015-09-25 | 2017-03-30 | 株式会社日立製作所 | Rotary machine diagnostic system |
| CN105354397A (en) * | 2015-12-08 | 2016-02-24 | 中国科学院电工研究所 | Design method for common-mode electro-magnetic interference filter for motor drive system |
| CN106569406A (en) * | 2016-11-07 | 2017-04-19 | 华侨大学 | Brush DC motor model parameter quick identification method based on scale transform |
| CN106991263A (en) * | 2017-05-25 | 2017-07-28 | 清华大学 | A kind of modeling method of mesolow distribution transformer winding thunder and lightning wideband model |
Non-Patent Citations (4)
| Title |
|---|
| 张飞: "电动汽车电机驱动系统传导电磁干扰的建模和实验研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 * |
| 汪泉弟: "低压永磁直流电机的传导电磁干扰模型", 《电机与控制学报》 * |
| 肖芳等: "PWM驱动电机系统传导干扰等效电路模型", 《变频器世界》 * |
| 郑琦琦等: "电机驱动系统的电磁干扰抑制方法研究", 《电气传动》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3786650A1 (en) * | 2019-08-27 | 2021-03-03 | Robert Bosch GmbH | Method and device for providing a behaviour model for simulating electromagnetic interference emissions of an electrical or electronic component |
| DE102019212783A1 (en) * | 2019-08-27 | 2021-03-04 | Robert Bosch Gmbh | Method and device for providing a behavior model for the simulation of electromagnetic interference emissions from an electrical or electronic component |
| DE102019212808A1 (en) * | 2019-08-27 | 2021-03-04 | Robert Bosch Gmbh | Method and device for providing a behavior model for the simulation of electromagnetic interference emissions from an electrical or electronic component |
| CN111025038A (en) * | 2019-08-28 | 2020-04-17 | 湖南大学 | Prediction method and system for radiation electromagnetic interference of electric drive system |
| CN113378358A (en) * | 2021-05-20 | 2021-09-10 | 同济大学 | Modeling simulation method for conduction and radiation interference of direct-current brush motor |
| CN113311238A (en) * | 2021-07-09 | 2021-08-27 | 福州大学 | Method for measuring impedance between cables by using two ports |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107783040B (en) | 2020-06-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107783040B (en) | Modeling method, device and system for electromagnetic interference of direct-current brush motor | |
| CN110188381B (en) | Method and system for constructing simulation model for electromagnetic interference prediction | |
| CN108680813B (en) | Electromagnetic interference modeling simulation method and device | |
| CN101714184B (en) | Behavioral level modeling system for circuit board level electromagnetic compatible sensitivity | |
| US20140300370A1 (en) | Efficient Method Based on the Electromagnetic Time Reversal to Locate Faults in Power Network | |
| CN108345753B (en) | Crosstalk noise prediction method for non-parallel cable | |
| Yang et al. | Using a two-step finite-difference time-domain method to analyze lightning-induced voltages on transmission lines | |
| CN104537261B (en) | A kind of containing through circuit interference predicting method in cable cabinet based on field circuit method | |
| CN102156788B (en) | Method for simulating transmission property of partial discharge signal in power cable | |
| Li et al. | Measurement-based modeling and worst-case estimation of crosstalk inside an aircraft cable connector | |
| Reuter et al. | Influence of a traction battery's input impedance on conducted emissions of an automotive HV inverter | |
| CN109709435B (en) | Method for measuring shielding effectiveness of high-voltage shielding cable of electric automobile | |
| CN110378008B (en) | Method for analyzing influence of cable parameters of electric drive system on electromagnetic interference of system | |
| Reuter et al. | The influence of network impedance on conducted disturbances within the high-voltage traction harness of electric vehicles | |
| Grassi et al. | SPICE behavioral modeling of RF current injection in wire bundles | |
| Wang et al. | Estimation of multi‐conductor powerline cable parameters for the modelling of transfer characteristics | |
| CN105373612B (en) | A kind of spacecraft ground connection figure automatic creation system and its method | |
| CN105158562A (en) | Time-frequency domain data processing method for whole machine lightning indirect effect experiments | |
| Antonini et al. | Spice equivalent circuit of a two-parallel-wires shielded cable for evaluation of the RF induced voltages at the terminations | |
| US11454656B2 (en) | Signal generating device and measurement device | |
| JP2014225875A (en) | Method and device for determining resistance of electric wire | |
| CN112347912A (en) | Converter transformer running state judgment method and device based on black box model | |
| Skibin et al. | High frequency cable models for system level simulations in power electronics applications | |
| Beltramelli et al. | Modeling conducted noise propagation along high-voltage DC power buses for electric vehicle applications | |
| Li et al. | Measurement-based models for crosstalk within a connector shell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: 4 / F, building 1, No.14 Jiuxianqiao Road, Chaoyang District, Beijing 100020 Patentee after: Beijing Jingwei Hirain Technologies Co.,Inc. Address before: 8 / F, block B, No. 11, Anxiang Beili, Chaoyang District, Beijing 100101 Patentee before: Beijing Jingwei HiRain Technologies Co.,Ltd. |
|
| CP03 | Change of name, title or address |