Abstract: A die assembly is disclosed. The die assembly includes a die, one or more die pads on a first surface of the die and a die attach film on the die where the die attach film includes one or more openings that expose the one or more die pads and that extend to one or more edges of the die.

Abstract: A die assembly is disclosed. The die assembly includes a die, one or more die pads on a first surface of the die and a die attach film on the die where the die attach film includes one or more openings that expose the one or more die pads and that extend to one or more edges of the die.

Abstract: A simulation evaluation model of a high voltage ride through capability includes a wind turbine system aerodynamic model, a torque control model, a converter model, and a high voltage fault generating device model connected in sequence; the wind turbine system aerodynamic model is configured to calculate an airflow input power; the torque control model is configured to calculate a rotor electromagnetic torque according to the airflow input power; the high voltage fault generating device model is configured to simulate a high voltage fault and output a predetermined voltage on a low voltage side of a transformer; and the converter model is configured to calculate a stator reactive current, an active power and a reactive power of the wind turbine system during the high voltage fault according to the airflow input power, the rotor electromagnetic torque and the predetermined voltage on the low voltage side of the transformer.

Abstract: A stability measuring method for a synchronous generator includes: S11: collecting electrical quantities, and setting an alarm PQ curve of the synchronous generator; S12: calculating a dynamic reactive power reserve, an inductive dynamic reactive power reserve and a capacitive dynamic reactive power reserve of the synchronous generator; S13: calculating a dynamic reactive power reserve target value, an inductive dynamic reactive power reserve target value and a capacitive dynamic reactive power reserve target value of the synchronous generator; and S14: calculating a capacitive stability, an inductive stability and a stability of the synchronous generator.

Abstract: Preparation methods of a high modulus carbon fiber (HMCF) and a precursor (mesophase pitch (MP)) thereof are provided. The preparation method of MP includes: separating components with a molecular weight distribution (MWD) of 400 to 1,000 from a heavy oil raw material through size-exclusion chromatography (SEC); subjecting the components to ion-exchange chromatography (IEC) to obtain modified feedstock oil, where, the components are passed through macroporous cation-exchange and anion-exchange resins in sequence to remove acidic and alkaline components; and subjecting the modified feedstock oil to thermal polycondensation and carbonization to obtain high-quality MP with prominent spinnability. With high mesophase content, low softening point, low viscosity, and prominent meltability and spinnability, the obtained MP is a high-quality raw material for preparing HMCFs. The obtained MP can be subjected to melt spinning, pre-oxidation, carbonization, and graphitization to obtain an MP-based HMCF.

Abstract: A simulation evaluation model of a high voltage ride through capability includes a wind turbine system aerodynamic model, a torque control model, a converter model, and a high voltage fault generating device model connected in sequence; the wind turbine system aerodynamic model is configured to calculate an airflow input power; the torque control model is configured to calculate a rotor electromagnetic torque according to the airflow input power; the high voltage fault generating device model is configured to simulate a high voltage fault and output a predetermined voltage on a low voltage side of a transformer; and the converter model is configured to calculate a stator reactive current, an active power and a reactive power of the wind turbine system during the high voltage fault according to the airflow input power, the rotor electromagnetic torque and the predetermined voltage on the low voltage side of the transformer.