1 Scope
This part of GB 12668 specifies electromagnetic compatibility (EMC) requirements for power drive systems (PDSs). A PDS is defined in 3.1. These are adjustable speed a.c. or d.c. motor drives. Requirements are stated for PDSs with converter input and/or output voltages (line-to-line voltage), up to 35 kV a.c. r.m.s.
PDSs covered by this part are those installed in residential, commercial and industrial locations with the exception of traction applications, and electric vehicles. PDSs may be connected to either industrial or public power distribution networks. Industrial networks are supplied by a dedicated distribution transformer, which is usually adjacent to or inside the industrial location, and supplies only industrial customers. Industrial networks can also be supplied by their own electric generating equipment. On the other hand, PDSs can be directly connected to low-voltage public mains networks which also supply domestic premises, and in which the neutral is generally earthed (grounded).
The scope of this part, related to EMC, includes a broad range of PDSs from a few hundred watts to hundreds of megawatts. PDSs are often included in a larger system. The system aspect is not covered by this part but guidance is provided in the informative appendixes.
The requirements have been selected so as to ensure EMC for PDSs at residential, commercial and industrial locations. The requirements cannot, however, cover extreme cases which may occur with an extremely low probability. Changes in the EMC behavior of a PDS, as a result of fault conditions, are not taken into account.
The object of this part is to define the limits and test methods for a PDS according to its intended use. This part includes immunity requirements and requirements for electromagnetic emissions.
Note 1: Emission can cause interference in other electronic equipment (for example radio receivers, measuring and computing devices). Immunity is required to protect the equipment from continuous and transient conducted and radiated disturbances including electrostatic discharges. The emission and immunity requirements are balanced against each other and against the actual environment of the PDS.
This part defines the minimum EMC requirements for a PDS.
Immunity requirements are given according to the environment classification. Low-frequency emission requirements are given according to the nature of the supply network. High- frequency emission requirements are given according to four categories of intended use, which cover both environment and bringing into operation.
This part may be used for the assessment of PDS. It may also be used for the assessment of CDM or BDM (see 3.1), which can be marketed separately.
This part contains:
- conformity assessment requirements for products to be placed on the market;
- recommended engineering practice for cases where high frequency emissions cannot be measured before the equipment is placed on the market (such PDSs are defined in 3.2.6 as category C4).
Note 2: The first edition of this part identified that the intended use could require engineering for putting into service. This was done by the "restricted distribution mode". Equipment that used to be covered by the "restricted distribution mode" is covered in the second edition by categories C2 and C4 (see 3.2).
This part is intended as a complete EMC product standard for the EMC conformity assessment of products of categories C1, C2 and C3, when placing them on the market (see definitions 3.2.3 to 3.2.5).
Radio frequency emission of equipment of category C4 is only assessed when it is installed in its intended location. It is therefore treated as a fixed installation, for which this part gives rules of engineering practice in 6.5 and appendix E, although it gives no defined emission limits (except in case of complaint).
This part does not specify any safety requirements for the equipment such as protection against electric shocks, insulation co-ordination and related dielectric tests, unsafe operation, or unsafe consequences of a failure. It also does not cover safety and functional safety implications of electromagnetic phenomena.
In special cases, when highly susceptible apparatus is being used in proximity, additional mitigation measures may have to be employed to reduce the electromagnetic emission further below the specified levels or additional countermeasures may have to be employed to increase the immunity of the highly susceptible apparatus.
As an EMC product standard for PDSs, this part takes precedence over all aspects of the generic standards and no additional EMC tests are required or necessary. If a PDS is included as part of equipment covered by a separate EMC product standard, the EMC standard of the complete equipment applies.
2 Normative References
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 2900.83-2008 Electrotechnical Terminology – Electrical and Magnetic Devices (IEC 60050-151:2001, IDT)
GB/T 4365-2003 Electrotechnical Terminology – Electromagnetic Compatibility (idt IEC 60050(161):1990)
GB/T 12668.1-2002 Adjustable Speed Electrical Power Dive Systems – Part 1: General Requirements – Rating Specifications for Low Voltage Adjustable Speed D.C Power Drive Systems (IEC 61800-1:1997, IDT)
GB/T 12668.2-2002 Adjustable Speed Electrical Power Drive Systems – Part 2: General Requirements – Rating Specifications For Low Voltage Adjustable Frequency A.C. Power Drive Systems (IEC 61800-2:1998, IDT)
GB/T 12668.4-2006 Adjustable Speed Electrical Power Dive Systems – Part 4: General Requirements – Rating Specifications for A.C. Power Drive Systems above 1 000 V A.C. not Exceeding 35 kV (IEC 61800-4:2002, IDT)
GB/T 17626.3-2006 Electromagnetic Compatibility – Testing and Measurement Techniques – Radiated Radio-frequency Electromagnetic Field Immunity Test (IEC 61000-4-3:2002, IDT)
GB/T 17626.8-2006 Electromagetic Compatibility – Testing and Measurement Techniques – Power Frequency Magnetic Field Immunity Test (IEC 61000-4-8:2001, IDT)
GB/Z 17625.5-2000 Electromagnetic Compatibility – Limits – Assessment of Emission Limits for Fluctuating Loads in MV and HV Power Systems (idt IEC 61000-3-7:1996)
GB/Z 17625.6-2003 Electromagnetic Compatibility – Limits – Limitation of Emission of Harmonic Currents in Low-voltage Power Supply Systems for Equipment with Rated Current Greater than 16A (IEC TR 61000-3-4:1998, IDT)
GB/Z 18039.5-2003 Electromagnetic Compatibility – Environment – Electromagnetic Environment for Low-frequency Conducted Disturbances and Signalling in Public Power Supply Systems (IEC 61000-2-1:1990, IDT)
IEC 60050-131:2002 International Electrotechnical Vocabulary (IEV) – Chapter 131: Circuit Theory
IEC 60146-1-1:1991 Semiconductor Convertors – General Requirements and Line Commutated Convertors – Part 1-1:Specifications of Basic Requirements
IEC 60364-1:2001 Electrical Installations Of Buildings – Part 1: Fundamental Principles, Assessment of General Characteristics, Definitions
IEC 60664-1:1992 Insulation Coordination for Equipment within Low-Voltage Systems – Part 1:Principles, Requirements And Tests
IEC 61000-1-1 Electromagnetic Compatibility (EMC) – Part 1:General – Section 1: Application and Interpretation of Fundamental Definitions and Terms
IEC 61000-2-2:2002 Electromagnetic Compatibility (EMC) – Part 2: Environment – Section 2: Compatibility Levels for Low-Frequency Conducted Disturbances and Signalling in Public Low-Voltage Lower Supply Systems
IEC 61000-2-4:2002 Electromagnetic Compatibility (EMC) – Part 2: Environment – Section 4: Compatibility Levels in Industrial Plants for Low-Frequency Conducted Disturbances
IEC 61000-2-6:1995 Electromagnetic Compatibility (EMC) – Part 2: Environment – Section 6: Assessment of the Emission Levels in the Power Supply of Industrial Plants as Regards Low-Frequency Conducted Disturbances
IEC 61000-3-2:2000 Electromagnetic Compatibility (EMC) – Part 3: Limits – Section 2: Limits for Harmonic Current Emissions (Equipment with Input Current ≤ 16 A per Phase)
IEC 61000-3-3:1994 Electromagnetic Compatibility (EMC) – Part 3-3: Limits – Limitation of Voltage Changes, Voltage Fluctuations and Flicker in Public Low-Voltage Supply Systems for Equipment with Rated Current ≤ 16 A per Phase and Subject to Conditional Connection
IEC 61000-3-11:2000 Electromagnetic Compatibility (EMC) – Part 3-11: Limits – Limitation of Voltage Changes, Voltage Fluctuations and Flicker in Public Low-Voltage Supply Systems for Equipment With Rated Current ≤ 75 A and Subject to Conditional Connection
IEC 61000-4-2 Electromagnetic Compatibility (EMC) – Part 4-2: Testing and Measurement Techniques – Electrostatic Discharge Immunity Test Basic EMC Publication
IEC 61000-4-4:1995
Amendment 1 (2000)
Amendment 2 (2001) Electromagnetic Compatibility (EMC) – Part 4: Testing and Measurement Techniques – Section 4: Electrical Fast Transient/Burst Immunity Test – Basic EMC Publication
IEC 61000-4-5:1995 Electromagnetic Compatibility (EMC) – Part 4: Testing and Measurement Techniques – Section 5: Surge Immunity Test
IEC 61000-4-6:2003 Electromagnetic Compatibility (EMC) – Part 4-6: Testing and Measurement Techniques – Immunity to Conducted Disturbances, Induced by Radio-Frequency Fields
CISPR 11 Industrial, Scientific and Medical (ISM) Radio-Frequency Equipment – Electromagnetic Disturbance Characteristics – Limits and Methods of Measurement
CISPR 14 Electromagnetic Compatibility – Requirements for Household Appliances, Electric Tools and Similar Apparatus
CISPR 16-1 Specification for Radio Disturbance and Immunity Measuring Apparatus and Methods – Part 1: Radio Disturbance and Immunity Measuring Apparatus
CISPR 212:2003 Information Technology Equipment – Radio Disturbance Characteristics – Limits and Methods of Measurement
3 Terms and Definitions
For the purpose of this document, the following terms and definitions apply.
3.1 Overview
For the purposes of this document, definitions related to EMC and to relevant phenomena to be found in GB/T 4365-2003, in CISPR, and also, the following additional definitions apply.
A power drive system (PDS) consists of a motor and a complete drive module (CDM). It does not include the equipment driven by the motor. The CDM consists of a basic drive module (BDM) and its possible extensions such as the feeding section or some auxiliaries (e.g. ventilation). The BDM contains converter, control and self-protection functions. Figure 1 shows the boundary between the PDS and the rest of the installation and/or manufacturing process. GB 12668.1-2002, GB 12668.2-2002 and GB 12668.4-2002 give details for these definitions.
Figure 1 Definition of the Installation and its Content
If the PDS has its own dedicated transformer, this transformer is included as a part of the CDM.
3.2 Intended use
3.2.1
first environment
environment that includes domestic premises, it also includes establishments directly connected without intermediate transformers to a low-voltage power supply network which supplies buildings used for domestic purposes
Note: Houses, apartments, commercial premises or offices in a residential building are examples of first environment locations.
3.2.2
second environment
environment that includes all establishments other than those directly connected to a low- voltage power supply network which supplies buildings used for domestic purposes
Note: Industrial areas, technical areas of any building fed from a dedicated transformer are examples of second environment locations.
3.2.3
PDS of category C1
PDS of rated voltage less than 1 000 V, intended for use in the first environment
3.2.4
PDS of category C2
PDS of rated voltage less than 1 000 V, which is neither a plug in device nor a movable device and, when used in the first environment, is intended to be installed and commissioned only by a professional
Note: A professional is a person or an organization having necessary skills in installing and/or commissioning power drive systems, including their EMC aspects.
3.2.5
PDS of category C3
PDS of rated voltage less than 1 000 V, intended for use in the second environment and not intended for use in the first environment
3.2.6
PDS of category C4
PDS of rated voltage equal to or above 1 000 V, or rated current equal to or above 400 A, or intended for use in complex systems in the second environment
3.3 Location, ports and interfaces
3.3.1
in situ (for test)
location where the equipment is installed for its normal use by the end user
3.3.2
test site (radiation)
a site meeting requirements necessary for correctly measuring, under defined conditions, electromagnetic fields emitted by a device under test
[GB/T 4365-2003]
3.3.3
port
access to a device or network where electromagnetic energy or signals may be supplied or received or where the device or network variables may be observed or measured
[IEV 131-12-60]
Note: Figure 2 illustrates the diversity of the ports of a PDS.
3.3.4
enclosure port
physical boundary of the PDS through which electromagnetic fields may radiate or impinge (see Figure 2)
3.3.5
port for process measurement and control
input/output (I/O) port for a conductor or cable which connects the process to the PDS as defined in Clause 3 (see Figure 2)
3.3.6
power port
port which connects the PDS to the power supply which also feeds other equipment
3.3.7
main power port
power port which feeds the PDS for only the power which, after electrical power conversion, is converted by the motor into mechanical power
3.3.8
auxiliary power port
power port which feeds only the auxiliaries of the PDS, including the field circuit if any
3.3.9
mechanical link
mechanical connection between the shaft of the motor of the PDS and the driven equipment of the process as defined in Clause 3
3.3.10
signal interface
input/output (I/O) connection for a line connecting the basic drive module or complete drive module (BDM/CDM) to another part of the PDS (see Figure 2)
Figure 2 Internal Interfaces of the PDS and Examples of Ports
3.3.11
power interface
connections needed for the distribution of electrical power within the PDS (see Figure 3 and explanation in Clause E.1 of appendix E)
Note: The power interfaces of the PDS may have different forms and extensions.
- Within the CDM/BDM
A power interface may be the connection for distribution of electrical power from one part of the BDM/CDM to another part of the BDM/CDM. One power interface may be common to different components of the PDS. For examples, see Figures 3 and 4.
Figure 3 shows a power interface which distributes power from an input converter (where power is converted from the mains to another type (here d.c. power)) to output inverters (where power is converted from an intermediate form (here d.c.) to another type (here a.c.) which can be directly applied to a.c. motors). Figure 4 shows a power interface which distributes power from the secondary of a transformer (which is part of the CDM) to individual BDMs.
- Within the PDS
Note that the connection between the inverter and the motor or the motors is also a power interface. It is the last power interface before the conversion to mechanical power.
Figure 3 Power Interfaces of a PDS with Common D.C. Bus
Figure 4 Power Interfaces with Common Input Transformer
3.3.12
PCC, IPC, PC
these definitions are given in IEC 61000-2-4
Note: Briefly:
- PCC is the point of common coupling on a public network;
- IPC is the in-plant point of coupling;
- PC is the point of coupling (for either of these cases).
3.4 Components of the PDS
3.4.1
converter (of the BDM)
the unit which changes the form of electrical power supplied by the mains to the form fed to the motor(s) by changing one or more of the voltage, current and/or frequency
Note 1: The converter comprises electronic commutating devices and their associated commutation circuits. It is controlled by transistors or thyristors or any other power switching semiconductor devices.
Note 2: The converter can be line-commutated, load-commutated or self-commutated and can consist, for example, of one or more rectifiers or inverters.
3.4.2
(electric) motor
electric machine intended to transform electric energy into mechanical energy
[IEV 151-13-41]
3.4.3
motor (of the PDS)
for the purposes of this part, the motor includes all sensors which are mounted on it and which are relevant for supporting the operating mode and interacting with a CDM
3.4.4
sub-component (of the PDS)
for the purposes of this part, a component of the PDS may be divided in subcomponents, each of them being a physical piece of equipment which can be operated separately with an intrinsic function defined by the manufacturer
Note: As an example, the control unit of a CDM may be a sub-component.
4 Common Requirements
4.1 General Conditions
All phenomena, from the emission or immunity point of view, shall be considered individually. The limits are given for conditions which do not consider the cumulative effects of different phenomena.
For a realistic assessment of the EMC situation, a typical configuration shall be chosen.
The application of tests for evaluation of immunity depends on the particular PDS, its configuration, its ports, its technology and its operating conditions (see appendixes).
4.2 Tests
4.2.1 Conditions
IEC 60146-1-1 and GB 12668.2-2002 distinguish between type test, routine test and special test. Unless otherwise stated, all the tests specified in this part are type tests only. The equipment shall meet the EMC requirements when measured by the test methods specified in this part.
Note: Due to local radio transmission legislation, some immunity tests can be subject to conditions which restrict the choice of location where they can be performed.
If necessary, safeguards shall be taken against any unintended effects on the total process that may result from an equipment failure while an EMC test is being conducted.
For the tests, unless otherwise specified by the manufacturer, the CDM shall be connected to a standard motor of adequate ratings with a cable and earthing rules defined by the manufacturer. In some cases, passive load conditions (resistive, or resistive and inductive) may additionally be applied (for example, for evaluation of the low-frequency emissions).
The description of the tests, the test methods, the characteristics of the tests and the test setups are given in the referred standards and are not repeated here. If, however, modifications or additional requirements and information or specific test methods are needed for practical implementation and application of the tests, then they are given in this part.
4.2.2 Test report
The test results shall be documented in a test report. The report shall clearly and unambiguously present all relevant information of the tests (for example: load conditions, cable laying, etc.). A functional description and detailed acceptance criteria provided by the manufacturer shall be noted in the test report.
Within the test report, the chosen test arrangements shall be justified. A sufficient number of terminals shall be selected to simulate actual operating conditions and to ensure that all relevant types of termination are covered. The tests shall be carried out at the rated supply voltage and in a reproducible manner.
4.3 Documentation for the User
The setting of limits and the structure of this part are based on the understanding that the installer and user are responsible for following the EMC recommendations of the manufacturer.
The manufacturer shall supply the documentation necessary for the installer of a BDM, CDM, or for the user of a PDS for the correct installation into a typical system or process in the intended environment.
If special EMC measures are necessary to fulfil the required limits, these shall be clearly stated in the user documentation. Where relevant, these can include:
- maximum and minimum acceptable supply network impedance;
- the use of shielded or special cables (power and/or control);
- cable shield connection requirements;
- maximum permissible cable length;
- cable segregation;
- the use of external devices such as filters;
- the correct bonding to functional earth.
If different devices or connection requirements apply in different environments, this shall also be stated.
A list of auxiliary equipment (for example, options or enhancements) that can be added to the PDS, and which complies with the immunity and/or emission requirements shall be made available.
This information may also be covered in some part of the test report to clarify the final recommended arrangement.
Contents
Foreword i
1 Scope
2 Normative References
3 Terms and Definitions
4 Common Requirements
4.1 General Conditions
4.2 Tests
4.3 Documentation for the User
5 Immunity Requirements
5.1 General Conditions
5.2 Basic Immunity Requirements – Low-Frequency Disturbances
5.3 Basic Immunity Requirements – High-Frequency Disturbances
5.4 Application of Immunity Requirements - Statistical Aspect
6 Emission
6.1 General Emission Requirements
6.2 Basic Low-Frequency Emission Limits
6.3 Conditions Related to High-frequency Emission Measurement
6.4 Basic High-frequency Emission Limits
6.5 Engineering Practice
6.6 Application of Emission Requirements – Statistical Aspects
Appendix A (Informative) EMC Techniques
Appendix B (Informative) Low-frequency Phenomena
Appendix C (Informative) Reactive Power Compensation – Filtering
Appendix D (Informative) Considerations on High-frequency Emission
Appendix E (Informative) EMC Analysis and EMC Plan
Bibliography
