摘要:
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.
摘要:
A frequency converter includes a radiating section having a base and fins for radiating heat from a power semiconductor, a circuit substrate being provided at an opposite side of the fins with respect to the base, a housing that covers the circuit substrate, a guide for flowing air between the housing and the circuit substrate toward a downstream side of the fins, and a fan. The fan flows the air flown to the downstream side of the fins by the guide toward an upstream side of the fins.
摘要:
A frequency converter includes a circuit substrate, a housing that covers at least the circuit substrate, a radiating section in which gases at an intake face are exhausted from an exhaust face so as to radiate heat, a fan provided on the exhaust face of the radiating section, and a guide provided on the housing to direct gases around the circuit substrate toward the intake face.
摘要:
An electric circuit module comprising: an electric device comprising an electric circuit to serve for passage and interruption of electric current, a packing material packing the electric circuit and a plurality of wiring members to electrically connect the electric circuit with an external circuit; and a heat sink to radiate heat from the electric device. The electric circuit module includes a fixture to fix the heat sink and the electric device together so that a heat radiating surface of the electric device comes into contact with the heat sink. The fixture is formed with a recess to accommodate therein a part of the electric device so that the heat radiating surface of the electric device is exposed from the fixture. When the electric device is fixed to the heat sink by the fixture, the heat radiating surface comes into contact with the heat sink.
摘要:
A control system for controlling a PWM inverter so that the inverter drives an induction motor at a variable voltage and a variable frequency while keeping constant a ratio of the output voltage of the inverter to the output frequency thereof, is disclosed which includes current component detecting means for detecting an effective current corresponding to a load, from the input current of the induction motor, frequency setting means for setting the output frequency of the PWM inverter, flux setting means for setting the amount of magnetic flux generated in the induction motor, correcting-frequency calculating means for calculating a frequency correcting quantity proportional to the effective current, and correcting-flux calculating means for calculating a flux correcting quantity proportional to the effective current. In a case where the detected effective current is judged to be less than a predetermined value, the frequency correcting quantity is added to the set output frequency to obtain an output frequency command, and the sum of the flux correcting quantity and the set amount of magnetic flux is multiplied by the value of the output frequency command to obtain an output voltage command, for the purpose of controlling the operation of the PWM inverter on the basis of the output frequency command and the output voltage command.
摘要:
A power module constructs a pressurizing tool by laminating an elastic member as well as a DC positive-side wiring member and DC negative-side wiring member in which currents flow in opposite directions. The pressurizing tool presses a first fixing tool, and then the first fixing tool presses semiconductor equipment. The semiconductor equipment is fixed to a heat dissipating member with its heat dissipating surface brought into surface contact with side wall surfaces of the heat dissipating member.The power module can enhance heat dissipation between a heat dissipating member and semiconductor equipment, and enables the semiconductor equipment to be fixed to the heat dissipating member without adding other components to the power module.
摘要:
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.
摘要:
An object of the present invention is to lower the voltage applied to the starting resistor of the starting circuit in a switching power supply circuit to reduce the power loss especially when the receiving voltage is high and thereby provide a small and inexpensive switching power supply circuit. According to the present invention, a switching power supply circuit comprises: a DC voltage section having two or more capacitors connected in series; and a PWM control circuit for receiving DC power supply from the DC voltage section and performing switching control on a primary side of a transformer in order for the switching power supply circuit to output a DC voltage of different voltage specifications; wherein the starting resistor for the PWM control circuit is connected to a connection point of the capacitors.
摘要:
A low noise, compact and low cost electric power converter employing a compact common mode transformer, and incorporating a line filter can reduce a leakage current, and can maintain predetermined leakage current reduction effect even if installation condition of the electric power converter or a characteristics of a semiconductor switching element is varied. The electric power converter including a capacitor, a first electrode, a second electrode, a first magnetic body, on which the first electrode and the second electrode are wound to form an LC composite element, connecting electrodes electrically connected to respective of both ends of the first and second electrodes, a second magnetic body for interlinking both ends of the first magnetic body, a coil wound around the second magnetic body in the same winding direction as the first and second electrodes wound around the first magnetic body and a resistor for shorting the output of the coil.
摘要:
An ON holding circuit is provided which outputs a signal which identifies an ON state of an insulated gate transistor to a gate voltage input circuit, and inhibits the gate voltage input circuit from being responsive to an input signal which identifies an OFF state of the insulated gate transistor when an overcurrent adjusting circuit operates continuously.