摘要:
A switching power source apparatus has a series circuit connected to both ends of a DC power source Vdc1 and having a reactor L3, a primary winding 5a of a transformer T, and a switch Q1, a series circuit connected to both ends of the primary winding and having an auxiliary switch Q2 and a clamp capacitor C3, a saturable reactor SL1 connected in parallel with the primary winding, a rectifying-smoothing circuit D1, D2, L1, C4 for rectifying and smoothing a voltage generated on a secondary winding 5b, and a control circuit 10 for alternately turning on/off the switches Q1 and Q2 and turning off the switch Q2 if a current of the switch Q2 increases due to saturation of the saturable reactor SL1. The reactor L3 is made of leakage inductance between the primary and secondary windings. In the transformer T, the primary winding is divided into two sections that are connected in series, the secondary winding is arranged between the two sections of the primary winding, and the numbers of turns of the two sections of the primary winding are adjusted to adjust the leakage inductance to saturate the saturable reactor SL1.
摘要:
A DC/DC converter according to the present invention includes a first switch connected to both ends of the DC power supply through a primary winding of a first transformer, a second switch connected to both ends of the DC power supply through a primary winding of a second transformer, a first series circuit connected between a node to which the primary winding of the first transformer and one end of the first switch are connected, and another end of the first switch, the first series circuit including a first diode, a smoothing capacitor, and an additional winding of the first transformer, which is connected to the primary winding of the first transformer in series, a second series circuit connected between a node to which the primary winding of the second transformer and one end of the second switch are connected, and another end of the second switch, the second series circuit including a second diode, the smoothing capacitor, and an additional winding of the second transformer, which is connected to the primary winding of the second transformer in series, a reactor connected to both ends of a series circuit in which a secondary winding of the first transformer and a secondary winding of the second transformer are connected in series, and a control circuit which turns on and off the first and second switches with a phase difference of half a cycle.
摘要:
A DC/DC converter according to the present invention includes first and second transformers, each including a primary winding and a secondary winding, the primary winding including first and second windings, a first diode connected to both ends of a series circuit including the DC power supply, a first switch, and the first winding of the first transformer, a second diode connected to both ends of a series circuit including the DC power supply, a second switch, and the first winding of the second transformer, a first series circuit connected to both ends of the first diode, the first series circuit including the second winding of the first transformer and a smoothing capacitor, a second series circuit connected to both ends of the second diode, the second series circuit including the second winding of the second transformer and the smoothing capacitor, a reactor connected to both ends of a series circuit including the secondary winding of the first transformer and the secondary winding of the second transformer, and a control circuit which turns on and off the first and second switches with a phase difference of half a cycle.
摘要:
The present invention provides a DC-DC converter including a first series circuit connected to both ends of a first switch and formed of a winding of a first transformer, a first reactor, a first diode, and a smoothing capacitor, a second diode connected to a connection point of a primary winding of the first transformer, the winding of the first transformer and the first switch, and to one end of the smoothing capacitor, a second series circuit connected to both ends of a second switch and formed of a winding of a second transformer, a second reactor, a third diode, and the smoothing capacitor, a fourth diode connected to a connection point of a primary winding of the second transformer, the winding of the second transformer and the second switch, and to the one end of the smoothing capacitor, a third reactor connected to both ends of a series circuit of a secondary winding of the first transformer and a secondary winding of the second transformer, and a control circuit which alternately turns on the first switch and the second switch every ½ cycle, turns off the first switch during an on-period of the second switch, and turns off the second switch during an on-period of the first switch.
摘要:
A power factor improving circuit including: a boost reactor that inputs a rectified voltage obtained by rectifying an AC power supply voltage of an AC power supply by a rectifier circuit; a main switch that inputs the rectified voltage through the boost reactor and is turned on/off; a converting section that converts a voltage obtained when the main switch is turned on/off into a DC output voltage; and a control section that controls turn-on/off of the main switch to shape an AC power supply current to a sine wave form, controls an output voltage of the converting section to a predetermined voltage, and controls a switching frequency of the main switch according to a value of current flowing into the AC power supply, or that of current flowing into the rectifier, or that of current flowing into the main switch.
摘要:
A switching power supply includes: a first series circuit, connected to both terminals of a direct current power supply Vdc1, in which a primary winding 5a of a transformer T, a reactor L3 and a first switch Q1 are connected in series; a second series circuit, connected to both terminals of the primary winding 5a and the reactor L3, which includes a switch Q2 and a capacitor C3; a smoothing circuit D1, D2, L1, C4; and a control circuit 10 alternately turning on and turning off the switches Q1, Q2. The transformer T includes: a main core 21, formed with a magnetic circuit, on which the primary and secondary windings 5a, 5b are wound with a given gap 23; and a plurality of auxiliary cores 24a, 24b disposed in the given gap 23 with a given distance in a circumferential direction of the primary winding 5a. Further, the reactor L3 is formed of a leakage inductance of the transformer T.
摘要:
An amplifying circuit, which generates a compensation current based on a detection result of a leakage current flowing between an AC power source for supplying power and a power converting circuit section, includes a main amplifier having transistors and a correction amplifier connected in parallel to the main amplifier. Capacitors are connected between each base of transistors, forming the main amplifier and the correction amplifier, and a ground line, and between an output terminal of the correction amplifier and the ground line, respectively, and an impedance ratio of these capacitors is adjusted, thereby adjusting an amplification ratio.
摘要:
A power factor improving circuit including: a boost reactor that inputs a rectified voltage obtained by rectifying an AC power supply voltage of an AC power supply by a rectifier circuit; a main switch that inputs the rectified voltage through the boost reactor and is turned on/off; a converting section that converts a voltage obtained when the main switch is turned on/off into a DC output voltage; and a control section that controls turn-on/off of the main switch to shape an AC power supply current to a sine wave form, controls an output voltage of the converting section to a predetermined voltage, and controls a switching frequency of the main switch according to a value of current flowing into the AC power supply, or that of current flowing into the rectifier, or that of current flowing into the main switch.
摘要:
A DC conversion apparatus includes a switch converting a DC voltage of a DC power source to a high-frequency voltage by being turned ON/OFF via a primary winding of a transformer, a series circuit of a switch and a clamp capacitor being connected to both ends of the primary winding, a synchronous rectifying circuit performing synchronous rectification of a high-frequency voltage generated at a secondary winding, a smoothing circuit smoothing a rectified output of the synchronous rectifying circuit by a smoothing reactor and a smoothing capacitor, a capacitor storing energy stored in the smoothing reactor due to a current backflow of the synchronous rectifying circuit caused under light load condition, a switch being turned ON in synchronization with the switch and returning the energy stored in the capacitor to the clamp capacitor on the primary side via the transformer, and a control circuit turning the switch and the switch ON/OFF states alternately.
摘要:
A DC/DC converter includes a first transformer and a second transformer each having primary windings and secondary windings respectively having first windings and second windings, a second switch connected to both ends of a first series circuit, a fourth switch connected to both ends of a second series circuit, a third series circuit being connected to both ends of the second switch and having the second winding and a second DC power supply, a fourth series circuit being connected to both ends of the fourth switch and having the second winding and the second DC power supply, a reactor connected to both ends of a series circuit having the secondary windings, and a control circuit turning ON/OFF the first and third switches with a phase difference of a half cycle and turning ON/OFF the second and fourth switches with a phase difference of a half cycle.