This part of GB/T 12668 gives the methods for the determination of voltage on the power interface of power drive systems (PDS's).
Note: The power interface, as defined in the GB/T 12668 series, is the electrical connection used for the transmission of the electrical power between the converter and the motor(s) of the PDS.
This part is applicable to for the determination of the phase to phase voltages (line voltage) and the phase to ground voltages (phase voltage) at the converter and at the motor terminals.
These guidelines are limited in the first issue of this document to the following topologies with three phase output:
—indirect converter of the voltage source type, with single phase diode rectifier as line side converter;
—indirect converter of the voltage source type, with three phase diode rectifier as line side converter;
—indirect converter of the voltage source type, with three phase active line side converter.
All specified inverters in this part are of the pulse width modulation type, where the individual output voltage pulses are varied according to the actual demand of voltage versus time integral.
Other topologies are excluded of the scope of this part.
Safety aspects are excluded from this part and are stated in GB/T 12668.5 series. EMC aspects are excluded from this part and are stated in GB/T 12668.3.
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.
IEC 61000-2-4 Electromagnetic compatibility (EMC)—Part 2-4: Environment —Compatibility levels in industrial plants for low-frequency conducted disturbances
3 Overview and Terms and Definitions
3.1 Overview of the System
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. If the PDS has its own dedicated transformer, this transformer is included as a part of the CDM.
In this part, the following agreement for all symbols is set, that:
—the index "head" means the peak value;
—the index "star" means bipolar value.
For a given drive topology, the voltage waveform patterns between the later defined sections are in principal constant as shape (including peak values), while their amplitudes depend on the suited operating voltages, assumed as reference values in each section.
Depending on the considered section interface and on the nature of the examined voltages (differential or common mode quantities), the reference voltages between sections are average DC or RMS fundamental AC quantities.
The actual voltage values shown between sections in the differential mode model and in the common mode model are evaluated as peak values: they are obtained starting from the corresponding reference values, multiplied by suited factors including the effect of the overvoltage phenomena.
GB/T 12668.8-2017 The following standards are cited:
GB/T 12668.8-2017 Cited by the following standards: