Abstract: This invention relates to the technical field of harmonic elimination for ferromagnetic resonance for a voltage transformer (abbreviated as PT), in particular, to a harmonic elimination method for ferromagnetic resonance for an active resistance-matching voltage transformer based on PID-adjustment, including compiling a resistance matching algorithm; designing and building a harmonic elimination control system based on the PID control strategy; presetting an active resistance-matching strategy; designing an engineering scheme for placing resistors.

Abstract: This invention relates to the technical field of harmonic elimination for ferromagnetic resonance for a voltage transformer (abbreviated as PT), in particular, to a harmonic elimination method for ferromagnetic resonance for an active resistance-matching voltage transformer based on PID-adjustment, including compiling a resistance matching algorithm; designing and building a harmonic elimination control system based on the PID control strategy; presetting an active resistance-matching strategy; designing an engineering scheme for placing resistors.

Abstract: An energy conversion device is provided. The energy conversion device includes a reversible pulse-width modulation (PWM) rectifier (102) and a motor coil (103). The motor coil (103) includes L sets of winding units, and each set of winding unit is connected with the reversible PWM rectifier (102), where L?2 and is a positive integer. At least two sets of heating circuits of a to-be-heated device are formed by an external power supply (100), the reversible PWM rectifier (102), and the winding units in the motor coil (103). The energy conversion device controls the reversible PWM rectifier (102) according to a control signal, so that a current outputted from the external power supply (100) flows through at least two sets of winding units in the motor coil (103) to generate heat.

Abstract: An ultra-high performance concrete (UHPC) with waste brick powder and preparation method and application thereof are provided, which relates to the technical field of concrete. The preparation method includes the following steps: stimulating activity of a brick powder by a method of mechanically stimulating activity to obtain waste brick powder; and preparing UHPC according to a mass ratio of cement to waste brick powder of 5:5-7:3 to obtain the UHPC with waste brick powder. The UHPC is prepared by treating waste bricks from construction waste (mechanically stimulating activity) to make waste brick powder with activity, therefore partially replacing cement. The UHPC is applied in a construction field.

Abstract: An ultra-high performance concrete (UHPC) with waste brick powder and preparation method and application thereof are provided, which relates to the technical field of concrete. The preparation method includes the following steps: stimulating activity of a brick powder by a method of mechanically stimulating activity to obtain waste brick powder; and preparing UHPC according to a mass ratio of cement to waste brick powder of 5:5-7:3 to obtain the UHPC with waste brick powder. The UHPC is prepared by treating waste bricks from construction waste (mechanically stimulating activity) to make waste brick powder with activity, therefore partially replacing cement. The UHPC is applied in a construction field.