Two-lap sequential control converters are usually adopted to supply and improve the power factor of input side. The line harmonic damage generated by a sequential control thyristor converter can be serious. To solve t...Two-lap sequential control converters are usually adopted to supply and improve the power factor of input side. The line harmonic damage generated by a sequential control thyristor converter can be serious. To solve this prob-lem and seek an optimum control strategy,we derived the changeable regular of the line-input-current,the fundamen-tal-frequency-current,the harmonic-current-content and the harmonic total distortion ratio of the converter at different firing angles. We obtained relevant data from experiments with a sequential control system of a DC 2.2kW/220V motor. With the example of the operating condition of a DC mine elevator,the harmonic current is two times approximately in sequential control compared to synchronous control when the firing angle of the two converters differs in 30°. At dif-ferent operating states of a two-lap connection converter,the ideal strategy is an exchange between sequential control and synchronous control,by which we can achieve the complementary goal of improving the power factor and har-monic effect. All analytical conclusions are supported by simulation and experimental results.展开更多
A fuzzy control scheme is presented according to the coal quantity in the main coal bunker, this method has a good dynamic response characteristic and is suited for complex nonlin-ear systems. The designation of self-...A fuzzy control scheme is presented according to the coal quantity in the main coal bunker, this method has a good dynamic response characteristic and is suited for complex nonlin-ear systems. The designation of self-adopting fuzzy controller, the working principle and functions of this system are also proposed, with the hardware and the main flow diagram of this system in-troduced in this paper.展开更多
基金Project GC06A523 supported by the Science and Technology Department of Heilongjiang Province
文摘Two-lap sequential control converters are usually adopted to supply and improve the power factor of input side. The line harmonic damage generated by a sequential control thyristor converter can be serious. To solve this prob-lem and seek an optimum control strategy,we derived the changeable regular of the line-input-current,the fundamen-tal-frequency-current,the harmonic-current-content and the harmonic total distortion ratio of the converter at different firing angles. We obtained relevant data from experiments with a sequential control system of a DC 2.2kW/220V motor. With the example of the operating condition of a DC mine elevator,the harmonic current is two times approximately in sequential control compared to synchronous control when the firing angle of the two converters differs in 30°. At dif-ferent operating states of a two-lap connection converter,the ideal strategy is an exchange between sequential control and synchronous control,by which we can achieve the complementary goal of improving the power factor and har-monic effect. All analytical conclusions are supported by simulation and experimental results.
文摘A fuzzy control scheme is presented according to the coal quantity in the main coal bunker, this method has a good dynamic response characteristic and is suited for complex nonlin-ear systems. The designation of self-adopting fuzzy controller, the working principle and functions of this system are also proposed, with the hardware and the main flow diagram of this system in-troduced in this paper.
