High - power high-frequency switching power supply
1. that full bridge phase shift soft switch control mode is adopt to eliminate the switching stress to the great extent, and the latest full bridge soft switch control IC in the United States is adopted, so that the function of automatically adjust and setting trigger pulse time sequence parameters is realized, the optimal IGBT switching time is achieved, and the IGBT switching loss is reduced to the minimum; and meanwhile, the synchronous rectification driving circuit is simplified by adopting the IC with the synchronous rectification driving function.
2. the advanced logic interlock control circuit is adopted to eliminate the false triggering of the pulse and overcome the short circuit of the bridge arm.
3. the problem of magnetic bias is eliminated, which mainly shows the following two aspects: ( 1 ) the main transformer adopts series DC isolation capacitor; ( 2 ) an automatic bias correction circuit is added.
4. the high-power high-frequency switching power supply adopts a multi-unit module parallel combination mode, and each unit module is controlled by high-speed digital network, so that the problems of signal attenuation and interference are well solved. At the same time, the control commands and parameters of each unit module are digitally transmitted by RS485 network through the whole machine controller, and each unit module has its own current and voltage automatic correction and adjustment system, so as to achieve the effect of complete current sharing.
5. the power supply module adopts the original imported IGBT ( Infineon, Siemens ) with better performance and higher efficiency as the main power device, and is matched with the low-loss and high-efficiency schottky diode packaged by Motorola and the synchronous rectifier tube with large current and low voltage drop as the rectifying device, thus improving the efficiency of the whole machine.
6. each module is exactly the same, replace the module, just dial the address code and need to replace the module, do not need to make any debugging.
7. each module has hot plug function, that is to say, the replacement module can be replaced without downtime, does not affect the user production.
8. high power high frequency switching power supply design are generally considered when using n + x redundant backup system, under normal circumstances, all module units are involved in the work, once one of the module failure, the system will automatically fault unit exit, other modules to share the fault unit current, make the total output voltage, current remains unchanged, at the same time can take out the fault module maintenance, greatly improve the reliability of the power supply.
Rs485 network control system ( single network )
1. RS485 network is used to concentrate the power supply, which has many advantages: simple control, high precision, only two-core shielded wire communication, simple wiring, digital transmission, high transmission precision, strong anti-interference ability, self-correction function and repeated data transmission function, strong interference ability, no signal attenuation, long communication distance, up to 1.2 km
2. each rectifier is internally provided with an RS485 network control card, which can convert analog signals in the rectifier into digital signals and transmit the digital signals to the upper computer / touch screen, and can simultaneously receive instructions from the upper computer / touch screen to control the power supply. All the power supplies are connected with the upper computer through the communication card and the PLC, each communication card can realize communication with 64 power supplies at the same time, and the number of the communication cards can be increased when the number of the communication cards exceeds 64
3. RS485 digital network rectifier itself has a digital intelligent controller, so need to change the power supply, only need to change the address of the power supply equipment, do not need to do any other adjustment, can be replaced, different models can be exchanged, maintenance is convenient and simple.
Rs485 network control system ( dual network )
Rs485 network control system ( two sets of network ) refers to the use of two sets of network control system, in the factory control, because the remote PC / touch screen and rectifier sometimes hundreds of meters apart, communication distance is very long, in order to avoid communication failure occurs in the way of digital transmission, using two sets of network control system, a set of system work, another set of system hot standby, when the main network communication failure, the system can automatically switch to the standby system work.
Profibus network control system
1. this set of network control system support general profibus network, site number can be arbitrary dial code, general GSD file, can support any network configuration, configuration mode is simple and easy to understand.
2. each control card ( a profibus slave site ) adopts RS485 network control mode to control the rectifier, RS485 communication line only need 2 core twisted pair shielded wire, can connect multiple rectifier with RS485 control card in series ( each site up to 13 )
3. the rectifier control and state part of the value, the user can define, without any restrictions.
4. support communication rate of 1.5 Mbps
Thyristor digital trigger control system
1. the digital trigger system solves the consistency problem of the pulse trigger signal, the trigger asymmetry degree is less than or equal to 0.07 degree,
Because analog trigger system can not keep consistency, it can make rectification equipment produce non-characteristic wave, so digital trigger can effectively reduce the interference to the equipment itself and the power grid.
2. the digital trigger system can provide the current system running control angle, running conduction angle value for PC display.
3. digital trigger system has advanced PID adjustment scheme, dynamic response time of 180 ms or less, overshoot of 1 % or less, and has to prevent the adjustment of oscillation, strict logic interlock circuit, prevent false triggering, pulse loss, out of sync, etc., with feedback line break or loss detection circuit, when the feedback line break or loss can identify and automatically enter the special pi adjustment state, and alarm. A plurality of PID adjusting schemes are prestored, so that the PID adjusting parameters can be automatically and manually set, the device is suitable for a plurality of use occasions, and the flexibility of the device is improved.
4. the digital control system has the phase sequence adaptive function, and provides two synchronization modes for users to select: one is three synchronization signals, and the other is a single synchronization signal.
5. the digital trigger system has a variety of given ways: manual given way can be selected to realize the conduction angle given under the condition of open loop; Or selecte an automatic given mode to realize closed-loop current regulation; It is also possible to allow that external current to be given by analog mean. Internal and external automatic given according to the principle of large effective work. The invention can realize undisturbed switch between manual open-loop and automatic closed-loop given modes.
6. the feedback signal can be DC current signal of DC current sensor, or select the AC transformer signal of rectifier transformer for feedback, can allow free switch between feedback, also can restrict each other, avoid accidental disconnection in the process of operation and cause current is too large.
7. digital trigger system also has the function of self - diagnosis, self - correction.
8. the digital trigger system has a dual channel system hot standby automatic switching function, normal work, the main channel work, when the main channel failure or power outage exit, standby channel immediately replace the main channel work, make the rectifier output is not affected, the whole process for undisturbed switch.