A Kind Of Energy-saving Bell Furnace Power Control System Research And Implementation

High-temperature sintering is a very important aspect of the produce process of the multilayer ceramic capacitors (MLCC), in order to obtain high-quality capacitors, a bell furnace that is hermetic and atmosphere in which is under control is needed. The target of the paper is atmosphere-style bell furnace of an electronic components manufacturer in Guangdong Province. The traditional chopper power regulation technology is applied in the temperature control system of the equipment, which would pollute the power grid because of abundant harmonic wave and low power factor. During the entire process of capacitor manufacturing, the cost that is spent on power consumption accounted for nearly30%of the whole cost. If power consumption in this aspect could be cut down, it will help the company Control production costs and enhance the competitiveness in the market.A new power control system is designed in this paper, which is base on multi-voltage synthesis theory. By using two back-to-back power switches connected together as the main circuit topology and combined with detection circuit, the system could regulate the temperature of the bell furnace. The paper focus on hardware design of the power control system and mainly to solve the following problems:1, Select low on-state impedance power switch, design main circuit structure which is used to control frequency alternating current according to the electrical characteristics of the power switch.2, Design the control strategy of the power switch according to multi-voltage synthesis theory and main circuit topology.3, Investigate related computational method of the power switch that is used in parallel to complete the design task of the main circuit.4, An improved thermal design program is proposed to effectively reduce the temperature of the semiconductor power devices.5, Introduce power electronic device protection circuit and the snubber circuit design methods.6, Complete the hardware design of the drive circuit and measurement circuit. Data that is obtained from software simulation and recorded from on-field debugging shows that the power control system designed in the paper contains less harmonic wave and has a higher power factor, it shows high precision of temperature control and excellent stability and reliability. Compared with the old equipment of the factory, the new one saves more than15%energy.