Toshiba Mitsubishi-Electric Industrial Systems Corporation

Mitsubishi Heavy Industries Limited

Wisconsin Alumni Research Foundation

Ryo Iida

Robert Donald Lorenz

Takashi Nakagami

Yang Xu

Yukai Wang

Yusuke Yoshino

A protection device is capable of protecting a load drive system at an appropriate timing according to a temperature of a power semiconductor. The protection device includes: a capacitor configured to output a voltage according to a charge accumulated by a first current; and a protection circuit configured to: (i) determine whether or not the voltage output by the capacitor exceeds a certain threshold value; (ii) generate a second current having a magnitude according to information related to the temperature of the power semiconductor which drives a load; and (iii) change a magnitude of the first current based on the second current.

Protection device, load drive system, protection method, and recording medium

An energization evaluation test equipment for an input filter of a large capacity PWM converter by reducing the power supply capacity to the equipment under test is provided. The energization evaluation test is equivalent to an actual load test. An equipment under test has an input filter connected to an output terminal of an AC power source and a PWM converter connected to an output terminal of the input filter to convert an AC power source to a DC power source. The evaluation test equipment includes a PWM converter input filter and a PWM converter configured similarly to the PWM converter input filter and the PWM converter of the equipment under test, respectively, a direct current reactor connected to an output terminal of a PWM converter of the equipment under test, a PWM controller for controlling the PWM converter of the equipment under test and controlling the PWM converter of the energization evaluation test equipment, wherein, outputs of the PWM converter of the equipment under test and the PWM converter of the energization evaluation test equipment are connected in series via the direct current reactor, and the PWM controller is performed so that the output voltage of the PWM converter of the equipment under test becomes a desired value and the output current of the PWM converter of the energization evaluation test equipment becomes a desired value.

Energization evaluation test equipment of a PWM converter input filter

A controller includes a torque command value calculation module configured to calculate a torque command based on a speed command of the motor, an output voltage controlling module configured to control an output voltage of the power converter based on the torque command calculated by the torque command value calculation module, a voltage command value correcting module configured to correct a voltage command to the power converter based on a measured output voltage from the power converter, a flux estimation module configured to estimate stator flux and rotor flux of the motor in a subsequent control period based on the voltage command by the voltage command value correcting module and a measured current of the stator and a motor speed estimation module configured to estimate a speed of the motor in a subsequent control period based on the flux estimated by the flux estimation module.

Controller for power converter

Growing community of inventors

Tokyo, Japan

Ryo Iida