Description of intermediate frequency power supply

Jul 08, 2022

Series resonance design can easily realize multi power supply smelting system, and the most common and typical is dual power supply system. The series resonant double output power cabinet and two furnace bodies form a smelting system with one electricity and two furnaces. The output power can be distributed steplessly and arbitrarily between the two furnace bodies, and the two furnace bodies can be powered at the same time, one for insulation and one for smelting, without using external switching devices to select the furnace body. The series resonance design of shennai power ensures the continuous and stable operation of the equipment and has a wide load matching range. The rectifier part of the power cabinet adopts a full open design, so the power factor is high and the high-order harmonic is small. The multi pulse design of the pulse further reduces the high-order harmonics. The unique rectifier trigger board design ensures the current balance between the incoming lines of each phase. At the same time, it implements soft start to prevent power shock and quickly cut off the power supply in case of failure. Digital signal transmission is realized through optical fiber, which has strong anti-interference ability and more stable system.

All components of series resonant double output intermediate frequency power supply are installed in a closed cabinet. The copper bars and tubes in the power cabinet are made of well-known domestic brands and are standardized. The components of the power cabinet are reasonably arranged, easy to maintain, and the wiring and wiring are standardized. Maintenance personnel can easily access all maintenance points. An isolating switch is set between rectifier and inverter. In case of inverter fault on one side, isolate the fault and continue to work with the power supply on the other side. The power cabinet is also equipped with smelting manager. It is a convenient smelting manager composed of man-machine interface. Its functions include: automatic furnace drying, cold furnace startup, fault diagnosis, fault information display and storage, operation information display, system status display, etc. A closed isolation control room is arranged on the upper part of the front door, which is equipped with the main control board, feedback board, control power supply and other control components, so that the signal of the main control board can be easily observed. The isolation control room does not require additional cooling. The main power electronic components of the power cabinet are water-cooled, and the temperature rise during the internal operation of the cabinet will not affect the isolation control room. At the same time, all electronic components on all electronic control circuit boards in the isolation control room are selected according to the high temperature level.

Installed on the front of the power supply, it is operated by the electric operating mechanism. There is a voltage loss coil for interlocking protection, and it has overcurrent protection. In case of overcurrent, it trips to protect and cut off the power supply from the incoming power supply to the power cabinet. The bridge rectifier converts AC into DC, providing a stable DC platform for the inverter. Two sets of series resonant inverter bridges, the output power can be steplessly and arbitrarily distributed between the two series resonant inverter bridges. Two sets of series resonant capacitor compensation devices to meet the dual output, which can simultaneously transmit power to two furnace bodies. The capacitor is installed in a fully enclosed capacitor cabinet and is made of high-strength cold-rolled steel plate.

At the same time, it is equipped with differential current mode, DC injection leakage furnace test alarm circuit, indicator light, leakage current meter and detection control circuit. During normal operation, it detects continuously. Turn off the power supply when the following conditions occur:

① Metal penetrates the furnace lining to the induction coil;

② There is too much moisture in the furnace lining;

③ Some electrical components have low resistance to ground.

Because the coil is made of oxygen free copper tube, the differential current mode and DC injection furnace leakage alarm circuit protect the whole coil, including effective coil and water-cooled coil. The differential current mode is an electronic protection with fast speed. When the output circuit has a flashover fault to ground, the differential current protection can respond at the fastest speed. DC injection furnace leakage alarm is a non electronic protection, which is relatively slow, but it can also detect furnace leakage when the power cabinet stops running. At the same time, shennai power can provide complete supporting equipment and various functional options according to customers' different configuration needs, so that you can feel the efficiency, convenience and safety brought by the newly developed products in an all-round way.