High Voltage Frequency Converter
The Frequency Converter takes high-speed DSP as the control core, adopts space voltage vector control technology and power unit series multi-level technology.With high reliability,easy operation and high performance as the design goals,it can meet the needs of users for various types of load speed regulation,energy saving and production process improvement .
System structure:
The structure of high voltage inverter is shown in Figure , includes phase shifting transformer, power cells and controller. 6kV series inverter contains 5 cells each phase, 15 cells in total. 10kV series inverter contains 8 cells each phase, 24 cells in total.
The structures of power cell are common, which are shown in Figure , it is the AC - DC - AC single phase inverter circuit, rectifier diodes are for the three phase full-wave, IGBT inverter bridge controlled by sinusoidal PWM technology
Features:
*Comprehensive waveform display and recording
The main control system can monitor the input current, voltage, output voltage and current in real time, display the waveform, and analyze the harmonic of each phase voltage and current, which is helpful for users to master various electrical parameters of the equipment
*Double loop control power supply, stable and reliable.
*High power density: small cell size, modular design; The whole machine is compact in structure and occupies little space.
*DC braking technology: when the motor is rotating (below 10Hz), DC braking current is applied to force the motor from rotating state to stopping state.
*Current limiting technology: when the inverter is running, if the current exceeds the limit value, limit the increase of current by reducing the frequency until the current is less than the limit value, and the inverter returns to the normal operating frequency.
*Overvoltage stall technology: during frequency reduction of the frequency converter, the motor generates electricity. When the bus rises, the frequency converter automatically lengthens the frequency reduction time to prevent the shutdown problem caused by bus overvoltage.
*Multiple control modes: local control, remote control box control and DCS control can be selected; Support MODBUS, PROFIBUS and other communication protocols; Frequency setting can be set on site, communication, etc; Support frequency preset, acceleration and deceleration functions.
*Acceleration and deceleration self-adaptive function: the frequency converter adjusts the acceleration time or limits the operating frequency of the motor according to the current load current of the motor, so as to limit the current and realize the function of no current during acceleration. During frequency reduction of frequency converter, the frequency reduction time is adjusted according to the bus voltage, so as to achieve the function of no overvoltage during frequency reduction.
*Black box function and intelligent analysis:
The equipment has the function of automatically recording the operation status and displaying, and can view the output current, output voltage, set frequency, operation frequency, input current and input voltage values of 200 points (100ms) before and after the protection, which is convenient for daily maintenance and rapid abnormal diagnosis.
Application fields
u Power generation fields
Water given pump, Condensate pump, Circulating pump, Booster fan, Compressor, Induced draft fan, Vacuum fan
u Petroleum fields
Air compressor, Induced draft fan, Injection pump, Submersible pump, Water circulating pump, Brine pump, Oil pump
u Coal and Mine fields
Hoister, Axial fans, Cleaning pumps, Mixing pumps, Dust fan, Mud pump, Water pump, Feed pumps, drain pump
u Metallurgy fields
Dust fan, Blast furnace blowers, Compressor fan, Oxygen Compressor, Feed pumps, SO2 fans, Cleaning pumps, Gas compressors
u Cement, and building materials fields
Raw mill fan, Cement mill fans exhaust fan, Heat fan mill, Dust fan, Circulating fan, Pressure fan
u Municipal areas
Pressure pump, Hot water circulation pumps, Sewage pumps, The water supply pump, Fan
u Chemical industry
Pressure pump, Compressor, Pump, Soft water pump, Blower, Fan
u Other fields
Air pump test stand, Wind tunnel test device
Technic parameter:
Type | Two quadrant high-voltage VFD | Four quadrant high-voltage VFD |
Applied motor power(kw) | 200kw-12000kw(4-pole motor is the standard,6-12pole motor is selected according to current) | 200kw-2000kw(4-pole motor is the standard,6-12pole motor is selected according to current) |
Rated output | Rated power(kw) | Rated power motor rated voltage 200kw-12000kw | Rated power motor rated voltage 200kw-2000kw |
Rated current(A) | Rated current of motor rated voltage | Rated current of motor rated voltage |
Overload capacity | 105% continuous,130% allow 1 minute,150% allow 3 seconds.180% immediate protection | 150% continuous,180% allow 1 minute.250% immediate protection |
Output voltage(KV) | Three-phase 0-6kv,(0-10kv) |
Waveform | Mutiplexed SPWM sine wave |
Input voltage | Phase/frequency/voltage | Three phase 50Hz 0-6kv,(0-10kv) |
Allowed volatility | Voltage:±10% Frequency:±5% -15%~35% derating for continuous operation. |
Basic performance | Start frequency | 0-10Hz can be set |
Accuracy | Analog setting:less than 0.3% of Max. frequency setting value(25± 10℃) Digital setting:less than 0.1% of Max. frequency setting value(-10± 50℃) |
Resolution | Analog setting:1/2000 of the Max. frequency setting value Digital setting:0.01hz(below 99.99hz) 0.1Hz(above 100hz) |
Efficiency | ≥98% at rated output |
Working | Power factor | ≥0.95 |
Operation | Local control(touch screen,cabinet door swtich)operation,remote extemal control operation,upper computer operation(optional) |
Given frequency | Touch screen digital given,muti-speed given,external control analog signal(DC4~20MA)given |
Working status output | Ralay status output,inverter fault,alarm.working/stop and other status indication |
Touch secreen | Input/output voltage,Input/output current,set value,fault status of each unit.working status,transformer status,bus voltage of each unit,etc. |
Protection function | Motor overcurrent, whole machine overvoltage, whole machine undervoltage, unit overcurrent, unit overvoltage, unit overheating, unit input phase loss, optical fiber communication failure, etc. |
Cooling method and enclosure protection grade | Forced air cooling/IP31 |
Control | Acceleration and deceleration time | 0.01~6000.0S, the acceleration and deceleration time can be set separately |
Voltage/Frequency Characteristics | Set by the set V/F curve |
PID | Manually set PID parameters |
Auxiliary function | V/F curve, low frequency compensation, rated current, current protection limit setting |
High voltage isolation | Electromagnetic coupling, multi-channel fiber optic transmission |
Control power input | AC 220V 2KVA |
Environment | Applicable places | Indoor, no corrosive or conductive gas, dust, direct sunlight, below 1000 meters above sea level (can be customized for high altitude areas) |
Ambient temperature/humidity | -10℃~+40℃/20~90%RH without condensation |
Vibration | 5m/s2 (below 0.6g) |
Storage temperature | -20 to +65°C (suitable for short-term storage such as transportation) |
| | | | |