YANTRA HARVEST Meduim Voltage Drives YANTRA HARVEST ENERGY PVT. LTD. Office No. 101, 102, 103, Plot No. 84, Survey No. 40, Ambedkar Road, Sangamwadi, Near RTO Office, Pune - 411001 (India) Tel / Fax : +91 20 26053200 E-mail - sales@yantraharvest.com, www.yantraharvest.com
Introduction Yantra-Harvest, a winning partnership of experience, technology and achievements in the Indian automation industry, now introduce HARSVERT-A, the new generation VFD from Yantra Harvest which is a multi-cell VFD with series-connect units, high voltage input and output. Beijing Leader & Harvest Electric Technologies co. Ltd is YANTRA HARVEST a high-technology company specializing in the R&D, manufacture, sales and service of medium voltage variable frequency system. Today, Beijing Leader is a market leader in the manufacture of VFDs in China, having catapulted to great heights within a short span of 5 years. They are an ISO 9001:2000 company, with a spectacular sales record to their credit. With a manufacturing unit in the Changping Yangfang Industrial Area of Beijing Leader & Harvest has always endeavored to meet the growing need of users and foster technological advance. Beijing Leader & Harvest has installed more than 3000 MV Drives which are working satisfactorily in various industry segments.
Capabilities Yantra primary technical services include automation and electrical engineering design, systems analysis, testing and support, systems integration, field service and commissioning, control, monitoring, testing and repair, with expertise in industries like: Oil and Gas Chemical and Petro-chemical Plants Automotive Plants Steel Plants Nylon and Tyre cord Plants Water and Effluent Treatment Power Generation and Utilities Pulp and Paper Pharmaceutical Industries Food and Beverages Textile Consumer Products Yantra is India's first company to have executed the largest MV Drive projects in India for MRPL and HPCL. LEADER & HARVEST has tirelessly endeavored to develop the medium voltage variable frequency drive (VFD) with high technology for years, meeting many challenges and quality demands in China. The products have passed the demanding test and inspection of the National Electrical Control Distribution Equipment Quality Supervision Inspection Center and the China Electric Power Research Institute as well as the product appraisal of the State Bureau of Machine Building Industry to obtain the Appraisal and Approval Certificate of New Product and New Technology granted by the State Economic and Trade Commission. LEADER & HARVEST relies on the first class technology foundation of a State Key Laboratory (Tsinghua University) and its experienced R & D team that continuously focuses on innovation and high quality. Their technical know-how and diligence has resulted in high-tech products, and after exploring market demands they have teamed up with production to introduce newer and better products.
Harnessing power, harvesting profits Application of HARSVERT-A medium voltage VFD series Power generation: Boiler feed Pumps Condenser water pump, I D Fans F D Fans P A Fans CW Pump Metal: Dusting Fans, Furnace Fans Descaling Pumps Converter ID Fans Petrochemical and chemical: Oil Transfer Pumps Compressors City construction: Water-supply Pump Compressors Mining: YANTRA HARVEST Mortar Pumps Fans / Blower Conveyer Paper & Pulp: I D Fans P A Fans In the above industries, the application of the HARSVERT-A medium voltage VFD series achieves smooth speed and flux control, which saves vast energy compared with the control of using the traditional wind shields or valves. Under certain circumstances, users' technological need is the reason of changing the speed of the fans and pumps. The HARSVERT-A medium voltage VFD series have remarkably high control accuracy, which can completely satisfy the technological requirements.
System Principle System Structure The structure of HARSVERT-A series medium voltage VFD is shown in fig A The system is composed of phase shifting transformer, power cells and controller. The 3300V series have 12 power cells, and every 4 cells make The fundamentals up a phase in series. The 6600V series have 18 power cells, every 6 cells make up a phase in series. The 11000V series have 27 power cells, and every 9 cells make up a phase in series. The structures of 3300V, 6600V and 11000V series VFDs are shown in fig A, B and C. Fig. A :System structure of 3.3kV series VFD Fig. B : System structure of 6.6 kv series VFD Fig. C : System structure of 11kV series VFD Power Cell Structure of HARSVERT-A Medium Voltage VFD The power cells are completely identical in structure, and can be replaced with each other. The circuit structure is shown in fig 3.2, it is a basic three phase input, single phase output AC-DC-AC VFD circuit. The rectifier is a threephase diode bridge. Controlling the IGBT inverter By sinwave PWM, the output voltage waveform is shown in fig 3.3. Input Side Structure The phase shifting transformer supplies power to each power cell on the input side. The transformer's secondaries are divided into three groups; for 3300V series, 24-pulse rectifier mode is formed; for 6600V series, 36-pulse rectifier mode is formed; for 11000V series, 48-pulse rectifier mode is formed. This multi-pulse Output Side Structure See fig A and fig B At the output side, each cell's U and V output terminals are connected in series to form a star connection to supply power to the motor. By overlapping each cell's PWM wave, we can get the multilevel SPWM waveform shown in fig E It has a excellent sineshape, small dv/dt, no cable and motor insulation destruction, no output filter for long output cable, no motor derating, and can be used in driving the old motor directly. Meanwhile the motor harmonic is reduced greatly, the mechanical vibration is eliminated, and the overlap rectifier mode greatly improves the line current waveform quality, and the load power factor can be improved up to near 1. In addition, the independence of the transformer's secondaries makes the power cell s main circuit relatively separate, It's similar to the normal low-voltage VFD, therefore, easy to utilize the mature technologies R S T mechanical stress of shaft and vanes is reduced. When a certain power cell has a fault, by automatically closing the relay K shown in fig C, the fault cell can be bypassed out without effect on other cells and-the VFD can run at a derated mode; so the loss due to the motor's suddenly shutting down can be reduced in many situations. A+ A- B+ K U V Fig. E : The PWM Step Wave of the Output phase voltage of High-Voltage inverter System
Building intelligence at every step Cell Bypass (Optional) Harsvert-A Drive has a cell bypass feature which makes the Drive "N-1" redundant. Easy to use Operator Interface Interface Terminal Membrane keypad includes function keys, cursor selection key for menu navigation, item selection and data entry. Standard operator device cluster includes, start, stop, and emergency stop pushbuttons, local/remote selector switch and local speed potentiometer. Integral Transformer Factory wired integral isolation transformer for easy, low cost, installation. Compatible with Standard Motors without Derating YANTRA HARVEST Motor-friendly waveforms have been the trademark of Harsvert Drive with near sinusoidal output current and voltage waveforms at all speeds and loads. Standard induction or synchronous motors are compatible without derating. Inverter duty motors are not required.
Qualities that make HARSVERT-A VFD unique Voltage source VFD, direct input of 3.3,4.16, 6.6, 11 kv, direct output of 3.3, 4.16, 6.6, 11 kv, no output transformer necessary. High efficiency. High input power factor, no power factor correction devices. Low input harmonic current, full accordance with IEEE 519-1992, no input harmonic filters required. Sinusoidal multi-level PWM output wavefrom, no output harmonic filters required, directly connected to the shafts or the vanes, allowing the maximal length of the output cable of 1000m. Friendly Human-Machine interface, easy to operate. Modular design of the power circuits simplifies maintenance routine. Medium voltage circuits are connected with controller by the optical fibers, which keep the controller safe and away from the disturbance. Complete fault monitor functions, accurate fault alarm and protection. Integrated cooling blower. The control logic can be conveniently changed in the integrated PLC. Offer both field control and remote control in monitor station. Support most of the industrial standard protocois. (Profibus, Modbus, TCP/IP etc.) Compatible with industrial standard signal of 0-10V/4-20mA. Open loop or closed loop operation with the integrated PID regulator. Complete system parameter set-up function of VFD. Easy installation. Excellent performance/ price ratio. Standard Specifications of HARSVERT-A VFD series Rated Output Capacity 250-6250 kva Applicable Motor Output 200-5000 kw Output Cell cascaded, Multi-level SPWM output Rated output Current < 600 A Rated input and output Voltage 3300-11000 V 10% Input Frequency Tolerance 45-55Hz Input Power Factor 0.95 (>20% of full load) System Efficiency > 0.96 (full load, including the input transformer) Output Frequency Scope 0.5 Hz - 120 Hz Output Frequency Resolution 0.01 Hz Overload Endurance 120% of rated current for 1 minute; 150% immediately Analogue Input Four channels, 0-10 V or 4-20 ma, more channels available Accel/ Decel Time 0.1-3000 sec. adjustable (load dependent) Logical Control Input/Output Signals Expandable by user's need 0 0 0 Ambient Temperature 0-40 C (45 C & 50 C available on demand) 0 Storage/Ttransportation Temperature -40-70 C Cooling Methods Air cooling or closed loop liquid cooling (Liquid to Air/Liquid heat exchanger available) Ambient Humidity < 90%, no condensation Altitude Maximum 1000 m above MSL; higher available Enclosure IP20, IP21, IP31 Size (WxHxD) 3300-10600 mm x 2480 mm x 1300 mm Weight 3000-19000 Kg Qualify Assurance ISO 9001:2000