基于储能电感的超声波发射电路本安化方法研究

Research on intrinsic safety design of ultrasonic transmitting circuit based on energy storage inductance

针对煤矿千米定向钻机钻进过程中应用超声波换能器对钻孔状态监测时存在需要高电压驱动和本质安全化无法兼备的问题,提出了一种基于储能电感的本安型超声波发射电路。介绍了发射电路的基本原理,理论研究了换能器等效阻抗和稳压管动态电阻对激励脉宽的影响;分析了发射电路内部和输出本质安全特性,据此给出了本质安全参数的判断标准和一种高电压本安型超声波发射电路参数计算方法。实验结果表明:在设计参数范围内,200 V幅值的激励脉冲宽度能够可达2~3μs,大于设计值1.5μs;测量储能电感电流为0.9 A,换能器等效电容为1.05μF,分别小于本安条件下的电流1 A、电容100μF。因此,本文所提方法得到的电路参数能够在输出高电压激励脉冲下,满足本质安全要求。

The high voltage driving and intrinsic safety cannot be combined when the ultrasonic transducer is used to monitor the drilling condition of kilometer directional drilling machines.To address this issue,an intrinsically safe ultrasonic transmitting circuit based on energy storage inductance is proposed.The basic principle of the transmitting circuit is introduced,and the effects of the equivalent impedance of the transducer and the dynamic resistance of the regulator on the discharge time and exciting pulse width of the energy storage inductance are studied theoretically.The internal and output intrinsic safety characteristics of transmitting circuit are analyzed.Then,a judgment standard of intrinsic safety parameters and a parameter calculation method of high voltage intrinsically safe ultrasonic transmitting circuit are illustrated.Experimental results show that the exciting pulse width of 200 V amplitude can reach 2~3μs in the range of design parameters,which is greater than the design value of 1.5μs.The measured energy storage inductance current is 0.9 A and the equivalent capacitance of the transducer is 1.05μF.The current is smaller than 1 A and capacitance is smaller than 100μF under intrinsically safe condition.Therefore,the circuit parameters obtained by the proposed method can meet the intrinsic safety requirements under the output of high voltage exciting pulse.