SDV Smart Device for Voltage Regulation and OLTC Monitoring

In a market that is more and more demanding for Quality of Supply, with stricter parametersfor acceptable supply limits there is an urgent need for tools that can adapt to this reality and provideacceptable voltage regulation.

In this context, the Smart Device for Voltage Regulation and OLTC Monitoring – SDV offers a solution that goes beyond the traditional and well known “90” relays. With novel resources providingoptimal control of voltage levelsfulfilling the most demanding regulations of this sector (e.g. ANEEL resolution 505).

Main Features

• Multiple configuration settings for regulation, activated by schedule according to time and day of the week or remote control;
• Two Ethernet fibre optics ports or RJ-45;
• Communication protocols: Modbus-RTU, Modbus/CTP, DNP 3,0, DNP 3.0/CTP and IEC 61850;
• RS-485 port for integrated operation with SPS paralleling supervisors, (not requiring the COMM-04 communication module) parallel commands as well as status information via communication protocols;
• Current measuring with clip-on CT increasing safety for the installation and maintenance personnel;
• Multi-measurement Function: displays of voltages in the transformer and load, voltage deviation, current, active, reactive and apparent power, load percentage, power and power factor;
• Adjustable VT/CT lag, from 0 – 300deg., allowing any variation of VT/CT connection;
• Independent actuation times for increase or decrease of voltage, with linear timing, linear in steps or inverse curve modes;
• Line drop compensation via resistance and reactance adjustments or through the simplified voltage drop percentage method (Z compensation).
• Control Center blocking in case of overcurrent and undervoltage.
• Selectable action in the event of overvoltage: blocking via the Control Center or quick voltage reduction;
• Three tap measuring inputs, facilitating the control three mono-phase transformers in one bank.
• Local and Remote and manual/automatic OLTC command;
• Parallel control between transformers or banks using Master-Follower, CirculatingCurrent or a combination of both methods in case of single-phase banks;
• Automating blocking of the tripped OLTC;
• OLTC Maintenance Assistant;
• Six signalling relays with programmable operation type and functions (NO/NC);
• Three analogoutputs for remote indication of variables.Configurable output band:        0…1, 0…5, 0…10, 0…20, or 4…20 mA.
• The combination of two analog outputs allows bipolar operation with the following bands:        -1…1, -5…5, -10…10 and -20…20 mA;
• Four inputs for dry contacts for remote commands, such as regulation program change, parallel control and others;
• Rugged construction, exceeding the EMC standards for operation in severe substationelectromagnetic conditions and operating temperature of -40 to 85ºC;
• Universal voltage , of 85~265 Vac or 85~275 Vdc;
• Compact dimensions, saving space and reducing panel cost;
• High brightness VFD display (Vacuum Fluorescent Display) readable under any lighting and temperature conditions;
• Non-volatile mass memory for measurements and alarms, internal clock maintained without the use of batteries, not requiring maintenance;

Accessories

PT100ΩW Temperature Sensor at 0ºC

Top  oil  temperature  in  power  transformers  is  usually  measured  by  a  temperature  sensor  installed  in  a thermowell on the transformer’s cover.  The sensors used with the IDV must be a Pt100W at 0ºCThese sensors are supplied with the appropriate size and fittings to suit the thermowells.

We also supply weather shields for ambient temperature measurement.

External Clip-on CTs (Split Core)

The use of external clip-on CTs with a split core window allows the installation of the temperature monitors without directly connecting the bushing CT secondary to the IDM. This eliminates the risk of accidentally opening the secondary and allows installation during transformer operation.

Outdoor cabinets

The IDV must always be installed in a shelter against the weather. The IDV can be installed in the transformer control panel. When this is inconvenient as when retrofitting old transformers the IDV can be supplied in a weatherproof cabinet.