Abstract: This article introduces the application of multi-level high-voltage frequency converter of Anbangxin Electronics Co., Ltd. on Tangshan Jingdong Cement tail exhaust fan. The working principle and production process of the frequency conversion system are analyzed. The results show that Anbangxin high-voltage frequency converter is in the cement industry. It can adapt well to the special working conditions of the industry and can completely replace imported equipment from abroad. It can achieve effective energy-saving and reduce equipment investment.
Keywords: high-voltage frequency converter cement industry fan energy saving
1 Introduction
Shenzhen Ampang Electronics Co., Ltd. main features of high-voltage inverter
l Well-known domestic high-voltage frequency conversion brand, high reliability, more than four years of safe operation experience, suitable for power plants, steel mills, cement, petrochemical and other applications
l Adopt all-digital speed sensorless vector control technology, with high control accuracy and fast response speed, greatly better than ordinary V/F control technology
l Excellent performance, very few input and output harmonics (36-pulse rectification, 13-level reversal)
l The internal transformer is dry, with insulation class H, higher than ordinary F class, high reliability, and easy maintenance
l Adapt to the grid fluctuation requirements, the grid voltage can be reduced up to 65%, and the inverter can continue to work without tripping
l Voltage source high voltage inverter, input power factor is greater than 0.96 in almost the entire speed section
l Smallest volume (including transformers), low cost of civil construction
l High-high structure, direct output 6KV high voltage, no change to the motor
l Unit failure automatic bypass function to ensure the safety and reliability of user production
l Chinese PC operation interface to bring convenience to users
l High efficiency of inverter, higher than 98.5%
l High IP30 protection level, higher than ordinary IP20, low user requirements
l Humidity up to 95%
l Anbang letter company has 10 offices and 22 representative offices across the country, 24 hours to respond to any user needs
l The performance of Anbang letter company is widely used in iron and steel, thermal power, cement, petrochemical, and water supply industries. Its performance is remarkable, its operation is reliable, and it brings good social and economic benefits to users.
Frequency conversion equipment basic components
36-pulse diode rectification, 13-level IGBT/PWM inverter
Integrated input dry isolation transformer with temperature measuring element
Protection class IP30, air-cooled throughout the frequency conversion system, air-conditioning cooling outside the cabinet
High voltage cabinet door protection chain
Control UPS
With PROFIBUS-DP communication interface
Basic performance of the inverter
l Inverter is a high-high structure, 6KV direct output, no need to output step-up transformer, the output is a series phase-shift type PWM, the output phase voltage is at least 13 levels, the line voltage is at least 25 level
l System integration design, including input dry isolation transformer, inverter and other components and internal connections, users only need to connect high voltage input, high voltage output, low voltage control power supply and control signal line. The entire system is tested as a whole before leaving the factory
l 36-pulse rectifier input meets and exceeds the most stringent requirements of IEEE 519-1992 and GB/T14519-93 standards for voltage distortion and current distortion
l Power factor up to or exceeding 0.96 within 20 to 100% load change (no power factor compensation required)
l The sinusoidal output current and voltage waveform can be output without the use of a filter frequency converter. There is no special requirement for the motor. An ordinary asynchronous motor can be used without derating the motor. With soft start function, there is no drop in grid voltage caused by motor starting shock, ensuring motor safety and long-term operation
l The inverter output waveform will not cause the motor resonance, and the torque ripple is less than 0.1%. Fan surge phenomenon can be avoided. Inverter has resonance frequency skip function
l The frequency conversion device does not require any output cable length, and the motor is not affected by common mode voltage and dv/dt
l Inverter can be used for no-load debugging without output motor, and can also be used for no-load debugging with low voltage without 6KV high voltage.
l Control adopts speed sensorless vector control and the starting torque can reach 200%
l The inverter has a strong ability to adapt to the voltage fluctuation of the power grid, and the voltage can still be derated when the voltage is lower than 35%.
l The inverter efficiency is 98.5%
l The control system adopts all-digital microcomputer control and self-diagnosis function
l Automatic detection of motor parameters and automatic optimization of control system parameters
l The inverter power unit communicates with the main control system using optical fiber connection, which has high communication speed and anti-jamming capability and good security.
l Automatic fault function of the unit fault, which can still guarantee system operation when the unit fails
l The control system has on-line detection of inverter input voltage, current, input power factor, output voltage, current, power, frequency, motor speed, etc.
l Frequency accuracy: ±0.5% (all factors)
l Overload capacity is 120%, 1min, to meet pump and fan load requirements
l Adjustable speed range: 0-100% continuously adjustable
l Acceleration/deceleration time 0.1-3600 seconds (can be set according to load conditions)
l Output frequency 0-120HZ (can be set according to the motor)
l Ambient temperature is -15 to +40°C, 95% relative humidity, 1000 meters above sea level
l The anti-seismic capability of the inverter is 7 grades, vibration 0.5G
l The critical speed can be skipped (a total of 3 groups can be set arbitrarily)
l User-adjustable digital meter, which can display speed, current, voltage, power, power consumption, etc.
Inverter control interface (can be expanded according to user requirements)
l 2 4 ~ 20mA or 0 ~ 10V analog input
l 4 4-20mA analog output or 0-10V for outputting motor voltage and frequency indication signals (expandable)
l 10 points switch passive input: automatic start/stop, manual start/stop, tight stop, reset, etc.
l 10 point switch passive output: frequency converter ready, operation, fault, etc. (capacity 220VAC/5A)
l 4-point switch passive output: capacity 220VDC/5A
l Inverter with PROFIBUS-DP communication interface, can transmit the output frequency, output voltage and other parameters to the PLC or DCS through the communication interface
structure
l The power unit of the inverter is a modular design. It can be withdrawn, moved and replaced from the rack. All units can be interchanged. The replacement unit does not require special tools. The time for replacing a unit is generally less than 10 minutes.
l Inverter side uses high switching frequency IGBT devices to ensure a good output waveform
l The isolation transformer on the input side can protect the motor from common mode voltage
l Air-cooled inside the entire frequency conversion system, external air-conditioning cooling
protection
l Frequency conversion device has overvoltage, overcurrent, undervoltage, phase loss, inverter overload, inverter overheat, motor overload, output ground, output short circuit and other protection functions
l The frequency conversion device has various protections of the isolation transformer
l Inverter with speed tracking restart function
Field Test
After the installation of the equipment is completed, Anbang letter company is responsible for checking the internal wiring and external wiring of the equipment to ensure successful debugging.
The frequency conversion device can withstand long-term operation under the conditions specified in the tender.
Measure inverter input and output voltage and current waveforms and harmonic content (When the motor starts, frequency is 25Hz, frequency is 38Hz, frequency is 50Hz)
Motor start performance test, start the motor, observe the current waveform and amplitude of the inverter output line, check the starting performance of the motor requires a small starting current, start torque, ensure stable start of the motor