Abstract: Stainless steel foil with improved durability to repeated bending under the extreme bending conditions demanded of foldable displays and rollable displays. This stainless steel foil is flexible stainless steel foil comprising rolled stainless steel foil with a thickness of 0.1 mm or less, having a tensile strength of 1,800 MPa or more, and having a maximum height roughness of Rz of 0.35 ?m or less obtained from a roughness curve of the stainless steel foil surface as measured in the same direction as a tensile direction.

Abstract: The purpose of the present invention is to provide a speed detection method for maintaining a fine time axis resolution and a power conversion device that uses the method. This power conversion device comprises an inverter for converting DC voltage into AC voltage and supplying the same to a motor, a motor speed calculation unit for calculating the speed of the motor from output pulses obtained from an encoder connected to the motor, and a control unit for receiving the motor speed from the motor speed calculation unit and controlling the inverter. In the power conversion device, the motor speed calculation unit measures the duty cycle of the output pulses, calculates the speed using the half cycles of the output pulses if the duty cycle is within a prescribed range from 50%, and calculates the speed using the full cycles of the output pulses if the duty ratio is outside of the prescribed range from 50%.

Abstract: With the aim of improving the reliability of a power conversion device for driving a motor, this power conversion device is provided with a rectifying portion for rectifying an AC voltage and outputting a DC voltage, a smoothing capacitor for smoothing the DC voltage, an inverter portion into which the DC voltage is input and which outputs AC power, an inverter drive portion for outputting a gate signal to the inverter portion, a regenerative braking portion connected in parallel with the smoothing capacitor, a regenerative braking drive portion for outputting a gate signal to the regenerative braking portion, a control portion for outputting drive signals to the inverter drive portion and the regenerative braking drive portion, a regenerative braking overcurrent detecting portion for outputting an overcurrent detection signal if the current flowing through the regenerative braking portion exceeds a determination value, and a latch portion into which the overcurrent detection signal output from the regenerati

Abstract: Provided are a power conversion device and a remote monitoring system capable of calculating the life of a power semiconductor device with high accuracy. In order to achieve the above purpose, a power conversion device, which controls the flow or interruption of a current with an inverter having a power semiconductor device and performs desired power conversion, comprises: a motor control unit which calculates a gate signal on the basis of a current value, a speed command, and a carrier frequency detected by a current sensor and controls the inverter; a temperature history calculator which estimates the loss of the power semiconductor device and calculates a temperature history; a temperature history storage device which stores the calculation result of the temperature history; and a damage calculator which calculates damage to the power semiconductor device from the temperature history read from the temperature history storage device.

Abstract: The purpose of the present invention is to provide a speed detection method for maintaining a fine time axis resolution and a power conversion device that uses the method. This power conversion device comprises an inverter for converting DC voltage into AC voltage and supplying the same to a motor, a motor speed calculation unit for calculating the speed of the motor from output pulses obtained from an encoder connected to the motor, and a control unit for receiving the motor speed from the motor speed calculation unit and controlling the inverter. In the power conversion device, the motor speed calculation unit measures the duty cycle of the output pulses, calculates the speed using the half cycles of the output pulses if the duty cycle is within a prescribed range from 50%, and calculates the speed using the full cycles of the output pulses if the duty ratio is outside of the prescribed range from 50%.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: A temperature detection method for a semiconductor device and a power conversion apparatus are disclosed. A temperature detection device is used to detect the temperature for thermal protection of a power semiconductor device. The temperature detection device is placed in the proximity of a component having the power semiconductor device packaged therein, and either an emitter terminal or a collector terminal of the power semiconductor device. Since the temperature detection device is mounted on a circuit board, it does not require insulation from a cooling fin on which the power semiconductor device is mounted and lead wires can be eliminated.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: In the present invention, miniaturization of an electric power conversion system is made possible while the reduction of a rise in temperature is achieved through a cooling operation by a cooling fan. The electric power conversion system is provided with a casing for covering cooling fins for cooling power semiconductors, a main circuit board having a driver circuit for driving the power semiconductors, and a cover for covering up the main circuit board. The system includes a first airflow hole provided at a part of the main circuit board, on the upper side of an air-intake provided in the cover, and a second airflow hole provided on the lower side of the first airflow hole, and on the lower side of the cooling fins, wherein air from the second airflow hole is driven to the cooling fins by a cooling fan.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: For applications in a facility where a power conversion apparatus is frequently started and stopped, a power conversion apparatus and a power cycle longevity estimation method are provided which improve an ease of use of the facility. The power conversion apparatus comprises power conversion circuits to supply ac power of variable voltage and variable frequency, a detection circuit to detect a temperature of the power semiconductor in the power conversion circuits, and a computation device to calculate a power cycle longevity of the power semiconductor based on a maximum temperature rise detected by the detection circuit.

Abstract: The invention provides a technique and a product in which for a frequency converter supplying electric power to, for example, a motor, a downsizing, lightening or the like of the frequency converter is realized while providing a filter apparatus reducing electromagnetic noises and the like. The filter apparatus reducing electromagnetic noises and the like is provided near a main circuit terminal board of the frequency converter, and the filter apparatus is connected directly to a main circuit terminal as a wiring drawing portion of the frequency converter. Part of a housing of the frequency converter and part of a filter housing are fitted to each other to fix the filter housing to the frequency converter.

Abstract: The performance of a power transducer is improved while efficiently using a power semiconductor also by managing the permissible duty factor of the power semiconductor in the regenerative braking circuit provided in the power transducer. The user is allowed to set, through an operation panel provided on the power transducer, the resistance value of the regenerative braking resistor for thermally consuming the rotational energy generated during motor deceleration. The power transducer performs the steps of: calculating the current which flows in the regenerative braking circuit from the resistance value setting; obtaining the generation loss of the power semiconductor in the regenerative braking circuit with the calculated current value; and determining the permissible duty factor of the power semiconductor from the obtained generation loss.

Abstract: The present invention provides an electric power converter in which a tip portion of a cooling fin on an air flow inlet side is limited to flow a large quantity of air around a connection portion, where the fin efficiency is high, of a base surface of the cooling fin and the fin so that the cooling efficiency of the cooling fin can be improved. By providing the limiting member, air or atmosphere flowing into the cooling fin is directed to flow toward the fin near the base surface. Further, by providing the limiting member, an area of a portion from which the air or atmosphere flows into the cooling fin is also limited so that the velocity of the air or atmosphere flow becomes high. By these functions and the like, the cooling efficiency of the cooling fin can be increased as compared to the prior art.

Abstract: A power converter in which a filter apparatus reducing noises is connected to a wiring drawing portion, wherein a conductor plate is arranged along an inner wall of a filter housing of said filter apparatus, and part of a housing of said frequency converter and part of a filter housing of said filter apparatus are fitted to each other to fix said filter housing to the housing of said frequency converter.

Abstract: A power converter in which a filter apparatus is connected to a wiring drawing portion, said filter apparatus including: a condenser element having an electronic part having an insulator as a dielectric material held between conductor plates; a sealing agent sealing said condenser element; a filter circuit comprising said condenser element; a connection conductor establishing wiring connections of said filter circuit; and a filter housing supporting said sealing agent.

Abstract: A power converter connected to a wiring drawing portion of a frequency converter, said filter apparatus including: a condenser element having an electronic part having an insulator as a dielectric material held between conductor plates; a sealing agent sealing said condenser element; a filter circuit comprising said condenser element; a connection conductor establishing wiring connections of said filter circuit; and a filter housing supporting said sealing agent.

Abstract: A filter apparatus connected to a wiring drawing portion of a frequency converter, said filter apparatus including: a condenser element having an electronic part having an insulator as a dielectric material held between conductor plates; a sealing agent sealing said condenser element; a filter circuit comprising said condenser element; a connection conductor establishing wiring connections of said filter circuit; and a filter housing supporting said sealing agent wherein said filter apparatus is fixed to said frequency converter based on a positioning portion provided in part of the housing of said frequency converter.