Folinn - Model DZB20HV Series - High Voltage Variable Frequency Speed Control System

Strong system stability

• Adopt Alternating-Direct-Alternating high pressure mode of sine wave SPWM superposition technology, superposition quarantine and power unit series;
• High integration technology and the full digital control system, strong anti-jamming capability                           
• Adopt twin-channel power supply automatic switchover supply design for control system, to guarantee stability of system;
• Manual bypass of complete machine, automatic bypass optional; while inverter faults, switch to power frequency for operation is available;
• Bypass function of circuit achieves redundancy design of power units;
• Duplicated hot-redundancy function optional: redundancy design; in some important occasions, two pieces offrequency conversion systems are used at the same time to drive a motor; while faults of one inverter, it can switch to the other frequency conversion system suddenly to guarantee continuous operation of system;
• Instantaneous stop/no stop function: while momentary power failure, feedback energy can be used to maintain short-time operation of inverter, and enhance system reliability;
• Power device voltage, sufficient electric current safety design margin, for enhancing  system reliability.

Vectorization V/F technology

• Although vector control mode has a favorable performance in theory, it is very sensitive with high-voltage motor parameters. If motor parameters are not stable, the performance will be given at a discount. But the parameter values of high-voltage motor`s stator resistance, rotor resistance, stator inductance, rotor inductance, stator mutual inductance and rotor mutual inductance are very small; and in operation process, due to increasing temperature and other factors, great changes will be generated. Real-time monitoring will be very difficult, so it is difficult to exert the performance of vector control performance. Fuling Electric mixes with low-pressure vector control technology and high-pressure vector control technology, and makes vectorization over the regular V/F control technology. The excellent performance of vector control is available, and it will not be sensitive to motor parameters.

Optimized PWM modulation technology

• The driving feature of three-phase motor is applied. On a basis of general PWM modulation technology, triple frequency harmonic shall be injected, and it can enhance utilization ratio of DC bus voltage better than traditional PWM modulation technique. It can reach 15% in theory. But triple frequency harmonic voltages are common-mode voltages, and current will not be generated within motors, so it will not have effects on motor operations. This technology can reduce unit input voltages, make units work under lower voltages, and enhance units stability.

Comprehensive parameter records

• High-voltage inverter displays multiple items of operational parameter records, including equipment frequency, stator voltage, stator current, draught fan pressure, power unit status, alarming record, faults record, self-diagnosis, etc.;
• All the parameter information can be uploaded to DCS by communication, and a comprehensive information record of abnormal information will be available on touch screen, so that field personnel can solve the problem more exactly and roundly.

Unit IGBT twin driving technology

• Unit IGBT adopts the unique twin driving technology. In the same carrier frequency, the on-off times of IGBT are reduced to effectively decrease switching loss, reduce IGBT heating, and enhance stability and efficiency of complete machine.
• Diversification of communication modes
• Strong parameter adjustment function, and the operations of start and operational mode can be set upon the spot working condition;
• Multiple upper computer communicating functions, quarantine 485 interface, standard MODBUS RTU communication protocol, optional PROFIBUS DP, and industrial ethernet communication protocol;
• Abundant extensible terminals, and equip inverter with expansion capability.
• Powerful monitoring function and protection function
• Perfect protection function. The power units are equipped with up to 16 protection functions, which guarantee the normal function of the power units.
• The electrical parts provide more than 20 super strong protection for the power source of inverter, overcurrent of motor, overload, undervoltage and temperature, etc.

Main system optimization

• The up-to-date type dual-core design uses the newest DSP and FPGA, which reduces devices and improves the stability;
• The software and hardware design of the master control system is internationally leading with the least devices. It’s simple and reliable;
• The traditional structure of base plate plus various function boards are no longer used. All the devices are distributed on a PCB, which completely eradicates the malfunction caused by poor contact of connectors.
• High efficiency, high power factor, low harmonic wave design.
• In cases of rated load, the overall efficiency ≥96%, and the input power factor≥95%;
• In cases of rated load, the input and output side harmonic content are both ＜2%;
• The optimized processing of DSP controlling system to modulation waveform ensures the perfect output without harmonic wave.
• More excellent energy-saving effect
• It is equipped with good energy-saving function. Normally, V/F control is normal value. The voltage is adjusted automatically, and the energy-saving effect is better;
• It is provided with many V/F curve controls that optimize the output voltage with different loading to reach different torque elevation.
• Galloping start of the inverter
• Reconnect the power ( within 10 seconds) after the bus of main power supply powers down. The inverter can automatically track the revolving speed of motor to fast find matched frequency to recover the operation ;
• The machine is not required to stop when power frequency changes the frequency. The inverter will automatically track the revolving speed of motor and run automatically, which ensures the rapidity of the system;
• Non-impact smooth start of the revolving motor can be realized, which is especially suitable for large inertia loading occasions, such as draught fans, etc.

Small volume

• Power density is improved through the structure optimization. The volume of complete machine is reduced by 20% than the peers, which reduces the on-site installation area.