StarSine Power Quality Products Medium Voltage Static Voltage Regulator ( MV SVR ) MV SVR PROTECTS THE WHOLE FACILITY LOADS FROM VOLTAGE SAGS CAUSED BY UTILITY GRID FAULTS Voltage sags, whether due to lightning, wind, ice, rodent, traffic accident, or due to any other reason, either at distribution or transmission levels, are a significant cause of automated production line and continuous process line shutdowns. Voltage sag events are inevitable and expensive (a production loss in excess of $1 million per event is often claimed by semiconductor manufacturers or automotive assemblers). SatCon s patented MV SVR substantially increases reliability of electric power delivered to your facility load bus. The MV SVR mitigates voltage sags at minimal capital and operating costs by providing an improved level of power quality without the addition of any expensive energy storage device. SPS1123 All information contained herein was accurate at the time of printing Page 1
List of Benefits MV SVR Features Reliable Voltage Sag Ride Through No Energy Storage Used High Efficiency - Low Operating Costs Application Specific Engineered Units Environmentally Friendly Benefits to Automated Facility Operators Meets the ITI (CBEMA) voltage tolerance curve requirements for voltage sags up to 50% of nominal and duration up to 10 seconds Power to compensate for the voltage sag is accomplished by drawing additional current from the sagged utility source 99.7% for facility loads of 8 MVA and up, no additional heat removal air conditioning (A/C) is required Units engineered to meet site specific requirements; load size, system voltage, fault currents, ambient T & H extremes The MV SVR design utilizes dry-type transformers and power electronics ambient air cooled When to Use a MV SVR The MV SVR is designed to provide low cost alternative to expensive voltage regulators requiring energy storage. As shown in summary of an EPRI survey of power quality disturbances for an average site, figure 1, the vast majority of voltage sags that results in loss of a process critical load are in the 50 to 90% range of nominal voltage and up to 10 seconds of duration. The MV SVR fully compensates for these sag levels preventing the majority of typical facility downtimes to provide for a quick payback and for high return on investment solution. Figure 1: Average Site Power Quality Disturbance Distribution per EPRI survey SPS1123 All information contained herein was accurate at the time of printing Page 2
Design and Principle of Operation A MV SVR unit consists of three single-phase voltage regulator cells (VR Cells) and of a control and communication cell (CC Cell). As shown on the VR cell circuit diagram (or SVR unit single line diagram) in figure 2, each VR cell includes a booster transformer (2), with its primary winding connected in series with the utility source, a regulator transformer (1) with a tapped secondary winding, which is connected through a string of tap static / power semiconductor switches (3) to the booster transformer secondary, and a crowbar static / power semiconductor switch (4). FROM SOURCE / UTILITY FEEDER M BOOSTER TRANSFORMER SOURCE ISO-SWITCH PRI 2 CROWBAR STATIC SEC SWITCH RLC FILTER 4 SS BYPASS SWITCH M TAP STATIC 3 SWITCHES TAP 7 TAP 6 SEC TAP 1 OFF ON 1 SS BYPASS & ISO-SWITCH GEAR LOAD ISO-SWITCH PRI REGULATOR TRANSFORMER MV SVR- VOLTAGE REGULATOR (VR) CELL TO LOAD / FACILITY DISTRIBUTION Figure 2: MV-SVR Unit Single Line Diagram (VR Cell Circuit Diagram) While the source voltage is above 90% of its nominal the MV SVR is operated in its feedthrough or no-boost operating mode. In this mode the crowbar static switch is closed and all the tap static switches are open. Closed crowbar static switch will short out the booster transformer secondary providing for virtually no drop of the source voltage while passed to load terminals. Upon the occurrence of source voltage sag, the control logic will sense the instantaneous sagged voltage level, determine which tap static switch to turn on and will command the static crowbar switch to open (turn off). The lower the source voltage, the higher the voltage tap that will be selected and connected to the booster transformer secondary as soon as the crowbar static switch is effectively turned off. In this regulating or boosting operating mode the tap voltage will show up at the booster transformer primary side and will add onto the sagged source voltage rebuilding or compensating the source voltage while delivered to MV SVR load terminal to above 90% of nominal level. SPS1123 All information contained herein was accurate at the time of printing Page 3
Operation Performance Operation of the MV SVR during a voltage sag event is demonstrated through source V input and load V output waveforms as shown at figure 3. The sag event was initiated at the negative peak during the shown third cycle after which source voltage stayed depressed at about 60% of its nominal for about 6 cycles. Source V Input Load V Output SVR Figure 3: MV SVR input and output voltages during no-boost and boosting operation It takes normally a quarter of a cycle for MV SVR control logic to detect the sagged voltage, to select the appropriate tap voltage and to start with rebuild or compensation of the source voltage. In subsequent half cycle the source voltage waveform is rebuilt beyond the 90% of nominal and passed to the facility load. Then the MV SVR load terminal voltage for inputs of voltage sags of up to 50% of nominal voltage and up to 10 seconds of duration at its line terminals fully meets the ITI (new CBEMA) voltage tolerance curve requirements. In addition, the MV SVR logic must determine if the source voltage sagged because of a fault on the load side or on the source side of the MV SVR. For voltage sag caused by downstream faults, the MV SVR stays in the no-boost mode until the appropriate downstream protection device clears the fault. The crowbar static switch is sized to withstand the full level of fault current for up to two recloser operations without the need for a rapid-closure of electro-mechanical bypass switch. This allows more flexibility in selecting bypass and isolation switchgear for MV SVR installations. Figure 4: MV SVR Switching Assembly SPS1123 All information contained herein was accurate at the time of printing Page 4
Technical Specifications Continuos Current (CC) Rating: Short-Circuit Current, 1 second: Nominal System Voltage Range: Frequency: Lightning Impulse Basic Insulation Level, BIL: 100 A through 1200 A Up to 12 ka RMS Sym 2.4 kv through 34.5 kv 50 Hz or 60Hz Up to 150 kv Voltage Sag Rebuild Capability: Maximum Inserted Voltage: 35% - 40% of nominal voltage Source Voltage Compensated: Beyond 90% Maximum Sag Rebuild Time: ½ cycle (8.33 ms for 60 Hz) Other SVR Unit Technical Data: Minimum Efficiency at > 75% of the CC Rating: Load Power Factor Range: Ambient Temperature Range: Ambient Humidity Range: Ambient Electro-Magnetic Compatibility (EMC): 99.7% (3 MVA minimum load) 0.75 inductive to 0.75 capacitive -10 C to 40 C standard 0-95% RH non-condensing Select IEEE, IEC, and FCC Std. Equipment Layout PLAN VIEW D PHASE A CELL PHASE B CELL PHASE C CELL Unit Installation Dimensions: 21 W x 20 D x 12 H for 300A, 21kV MV SVR Unit W Unit Weight: ELEVATION PHASE A CELL PHASE B CELL PHASE C CELL H 35,000 lbs. Approx. for 300A, 21kV MV SVR Unit BOTTOM INTERCONNECTION CABLE ENTRY SPS1123 All information contained herein was accurate at the time of printing Page 5
Improved Uptime of Your Business MV SVR is designed to improve the uptime of your business by significantly improving the reliability of electric power service. Businesses, which can particularly benefit from MV SVR improved power service include: Manufacturers of semiconductors and its production tools Operators of automotive assembly lines Operators of paper machines, plastic film machines and other continuous process machine types Owners of industrial parks and commercial building complexes MV SVR Design Patent: U.S. Patent Number 6,137,277 For more information about how MV SVR can specifically benefit your operation and be fitted in your facility power service application please refer to SatCon Power Systems (formerly Inverpower Controls) product pages and virtual library at www.satconpowersystems.com or contact us directly: ISO 9001 Certified SatCon Power Systems Canada Ltd. Telephone: 905-639-4692 835 Harrington Court Fax: 905-639-0555 Burlington, Ontario, Canada L7N 3P3 E-mail: sales@satcon.com SPS1123 All information contained herein was accurate at the time of printing Page 6