Functional block diagram of the TRIM/PoW relay
Use of the TRIM/PoW with a shunt reactor
General presentation
The TRIM/PoW device is designed for the controlled switching of reactors, capacitors and power transformers (TRIM function: “TRansformer Inrush current Minimizer”).
Energising the various components of a power network, such as transformers, capacitor banks or reactors, always involves a risk of transient overvoltages and overcurrents. De-energising these components can also cause overvoltages and restrikes. For example, energising an unloaded transformer often causes inrush currents of extremely high amplitude. This damages the mechanical structure and the insulation of the windings, and shortens the life of the transformer.
The most effective way to deal with these problems is to remove their root cause: finding the optimum instant for energising and de-energising. The purpose of controlled switching is to determine this instant (point on wave) and to delay the closing and opening commands of the circuit breaker accordingly.
Different electrical equipment naturally requires different energising strategies because of their distinct physical characteristics. The “Point-on-Wave” (PoW) switching functionality applies to the controlled energising and de-energising of reactors, capacitors and power transformers (as the TRIM function).
Although it belongs to the control and command family, the TRIM/PoW is part of the DAUT family of the PROTECTA range. Like the latter, it is modular in both hardware and software terms. Thanks to this, the modules are assembled and configured according to the user’s needs; from then on, the software determines the functions (SFB).
Our control and command relays are specially designed for versatile automation and control functions on power networks, such as supply switching, voltage measurement point switching, automatic synchronising, arc suppression coil control, etc.
The EuroCAP configuration software, available free of charge, provides a user-friendly and flexible application for protection, control and measurement functions, allowing the use of fully customisable devices.
General features
- Native intelligent electronic device (IED) compliant with the IEC 61850 standard, Edition 2 compatible
- Scalable hardware adapting to different applications
- Rack width of 84TE or 42TE (height: 3U)
- The predefined factory configuration can be customised to the user’s specifications with the powerful EuroCAP tool
- Flexible protection and control functionalities to meet specific user requirements
- Advanced HMI functionalities via a colour touch screen and a built-in web server, extended measurement, control and monitoring functions
- User-configurable LCD displays, able to show single line diagrams (SLD) with switchgear position indication and control, as well as measurement values and several types of controllable objects.
- Various protection setting groups available
- Enhanced circuit breaker monitoring and control
- High-capacity disturbance recorder (DRE) and event logging (data stored in non-volatile memory):
- DRE supporting up to 32 analogue signal channels and 64 digital signal channels.
- The event recorder can store more than 10,000 events.
- Several mounting methods: rack-mounted; flush-mounted; semi-flush-mounted; wall-mounted; wall-mounted with terminals; flush-mounted with IP54-rated cover.
- Wide range of communication protocols
- Ethernet communication: IEC 61850; IEC 60870-5-104; DNP3.0 TCP; Modbus TCP
- Serial communication: DNP3.0; IEC 60870-5-101/103; MODBUS, SPA
- The PROTECTA range can handle several communication protocols simultaneously.
- Built-in self-monitoring function to detect internal hardware or software errors.
- Various time sources available: NTP server; minute pulse; legacy protocol master; IRIG-B000 or IRIG-B12X
Applications
The TRIM/PoW device is a unique integrated electronic device designed for the controlled switching of reactors, capacitors and power transformers. The optimum switching instant is calculated from the network voltage and from the residual flux measured in the iron cores at the last interruption. The TRIM/PoW device can be used with three-phase circuit breakers with either ganged or independent pole operation; a version for single-phase circuit breakers (railway applications) is also available.
This control and command electronic device integrates a wide range of control and supervision functions, allowing full control and the implementation of user-defined interlocking schemes for the primary switchgear of the substation.
Field of application
- Controlled switching of reactors, capacitors and power transformers.
- Control device for three-phase or single-phase two-winding transformers, with a TRIM function and several additional control functions
- The circuit breaker type is defined by the parameter settings (individual, common, with or without a fixed delay between pole switching)
- As the residual flux is measured in the winding cores, the TRIM function works correctly even if the transformer is fitted with long cables having high capacitances
- Programmable closing schemes
- The resulting inrush current can optionally be measured.
Protection and control functions
The TRIM configuration measures the three-phase voltages on both sides of the circuit breaker of the transformer to be switched. These measurements are required to calculate the optimum closing instant of the circuit breaker in order to obtain inrush currents with minimum peak values. Current measurement is optional; it can provide information on the effectiveness of the controlled switching. This configuration also includes a circuit breaker control function, as well as optional additional control functions for the circuit breaker and the disconnector.
Click on the link to download the general documentation : Technical documentation PROTECTA Line
Operation manual : TRIM OMC1 14LA0771582
Click on the link to access the technical documentation to attach to your order : DOCACOM_PROTECTA
