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This paper describes the fundamental characteristics of a new magnetic oscillation direct current/alternating current (dc-ac) power converter that had fast recovery diodes added to it. The converter is constructed with a non-linear magnetic core and power MOSFETs. An ac-voltage source such as that for line electric power is connected in series to an excitation winding of the magnetic circuit. The converter can supply electric power to the ac-voltage source, and its output electric power can be controlled with a small signal current that flows through the control winding. The waveform for the output current of the converter is almost sinusoidal. The output electric power of the converter was increased by adding the fast recovery diodes outside the MOSFETs to cancel and replace the body-diodes of the MOSFETs.

This paper describes the numerical analysis of fundamental characteristics of a magnetic oscillation direct current/alternating current (dc-ac) power converter that can supply electric power to an ac-voltage source such as a line electric power source. We present a simulation model of the magnetic oscillation circuit based on a general purpose circuit simulation program called “SPICE” to quantitatively analyze it. The simulation results of the fundamental characteristics agree well with those from experiments. A method of improving the characteristics to control the output electric power, which is based on the analytical results, is also described in this paper.

This paper describes fundamental characteristics of a magnetic oscillation-type dc-ac power converter using bridge-connected magnetic circuit. An ac-voltage source such as the line electric power source is connected to an excitation winding of the magnetic oscillation circuit in series. The dc-ac converter can supply electric power to the ac-voltage source, and can control its output electric power with small dc-current, which flows through a winding of a U-form core of the bridge-connected magnetic circuit. Operation principle and fundamental characteristics of the converter are presented in this paper.

This paper describes the fundamental characteristics of a magnetic oscillation dc-ac power converter using a magnetic control device called a bridge-connected magnetic circuit. An ac-voltage source such as a line electric power source is connected in series to an excitation winding of the magnetic oscillation circuit. The converter can supply electric power to the ac-voltage source, and can control its output electric power by means of a small dc current that flows through a winding of a U-form core that composes the bridge-connected magnetic circuit. The characteristics of the converter in controlling the output electric power are described in this paper.

This paper describes fundamental characteristics of a direct current/alternating current (dc-ac) converter utilizing magnetic oscillation. An ac-voltage source such as the line electric power source is connected to an excitation winding of the magnetic oscillation circuit in series. The dc-ac converter can supply electric power to the ac-voltage source, and can control electric power with small signal current, which flows through a control winding. The electric power conversion efficiency of the dc-ac converter is improved by adding a small switching circuit into the converter. Output current waveform of the converter is almost sinusoidal.

In previous papers, we presented a magnetic oscillation dc-ac converter with sinusoidal output. An ac-voltage source such as line electric power is connected to the excitation winding of a magnetic circuit in series. The current flowing through the ac-voltage source can be controlled by small signal-current flows through the control winding of the magnetic circuit, according to the law of equal ampere turns. The converter can, therefore, supply electric power to the ac-voltage source when a small signal current is in phase with the voltage of the ac-voltage source. In this paper, we present a new magnetic oscillation dc-ac converter using a bridge-connected magnetic circuit. A small signal current is generated by utilizing the bridge-connected magnetic circuit, and the output electric power of the converter can be controlled by the dc current of a U-form core winding for the bridge-connected magnetic circuit. The characteristics of the converter in controlling the output electric power are described in this paper.

In a previous paper, we proposed a magnetic oscillation type dc-ac converter with sinusoidal output. An ac-voltage source is connected to an excitation winding of the magnetic circuit in series. The converter can supply electric power to the ac-voltage source because the current flowing through the ac-voltage source can be controlled by small signal-current flows through a controlled winding of the magnetic circuit according to the law of equal ampere-turns. This converter could be used in an electric-power interconnection system. This converter, however, does not have enough power conversion efficiency for practical use yet. In this paper, we present a new magnetic oscillation-type dc-ac converter with improved efficiency. The basic characteristics of the converter are described in this paper.

In a previous paper, we proposed a bridge-connected magnetic circuit with parallel output winding made up with a toroidal core with a rectangular B-H loop, a U-form core with low permeability, and two diodes. The value of the magnetic saturation flux of the toroidal core apparently decreases when the value of the dc current flowing in the U-form core winding increases, maintaining the rectangular B-H loop. In this paper, we present a new ferro-resonant circuit constructed by using the bridge-connected magnetic circuit with parallel output winding. The amplitude of the output voltage of the ferro-resonant circuit can be easily controlled by adjusting the dc current of U-form core.

In a previous paper, we proposed an oscillating circuit that included a bridge-connected magnetic circuit. A square-shaped output voltage is obtained in the oscillating circuit. The pulse width in the positive and negative half-cycles of the output voltage changes with the current flow in the U-form core windings and the signal voltage applied to the exciting windings. Furthermore the average value of the output voltage varies in proportion to the product of the current value and the signal voltage value. In this paper, we present a dc power-measuring circuit as an application of the oscillating circuit. The dc power measuring circuit proposed here has various advantageous characteristics, including a simple construction and a very small zero-drift in the output voltage.

In this paper, we describe a numerical model of a bridge-connected magnetic circuit for use in the SPICE simulation system. The model was devised on the basis of a bridge-connected magnetic circuit with saturation and hysteresis effects. As an example of application of the SPICE model, we analyzed using a bridge-connected magnetic circuit and a saturable core the transient behavior of a power measurement circuit caused by the principle of magnetic oscillation, The calculated results agree well with measurements. A SPICE model of the bridge-connected magnetic circuit presented here is useful for analysis and design optimization of power measurement circuits.

This paper describes the operating characteristics of a new reactor circuit using an inductance, a transformer and a resistance. The reactor circuit utilizes both the line and phase voltages of three-phase voltage source, and can reduce the 5th harmonic component of output voltage by changing the value of resistance connected to the transformer. An application of the reactor circuit to a filter circuit to remove the 5th harmonic voltages of three-phase source is presented in this paper.

In this paper, we propose a new sinusoidal-wave inverter utilizing magnetic oscillation circuit.

The authors describe the operating characteristics of an oscillating circuit using a bridge-connected magnetic circuit and another magnetic core. A square-shape output voltage is obtained in the oscillating circuit. The pulsewidth in positive and negative half cycles of output voltage changes with the current of the U-form core windings and with the signal voltage applied to the exciting windings. The mean value of the output voltage varies in proportion to the product of the current and the signal voltage. Utilizing this feature, an application of the oscillating circuit to a novel power measuring circuit of simple construction is presented. >

Application of a single-crystal 3% silicon-iron sheet with A rectangular B-H loop and very high induction to a bridge-connected magnetic circuit is described. The maximum flux value of the silicon-iron sheet in the magnetic circuit is controlled by the DC current. Utilizing this feature, a parametric transformer with variable output voltage was developed. The transformer is described. >

In the previous paper, we reported a reactor circuit which can decrease the 5th harmonic component from its output voltage[1]. In this paper, we describe fundamental operation of a bridge-connected three-leg magnetic circuit. The magnetic circuit is constructed by combining a three-leg core and a E-shape core, and can remove the 5th harmonic fluxes in the three-leg core. An application of the magnetic circuit to a removable 5th harmonic voltage transformer is also described in this paper.

This paper describes the performance characteristics of a bridge-connected magnetic circuit in ac control. The value of output current is easily controlled by varying the phase difference between the control current and supply voltage.The operation characteristics of a push-pull circuit using two bridge-connected magnetic circuits are also described in this paper.

This paper describes operating characteristics of a new parametric transformer with variable output voltage. The parametric transformer is constructed with two of a bridge-connected magnetic circuit, and the value of the parametrically-generated output voltage is easily controlled by dc current. An application of the parametric transformer to a dc power stabilizer with high performance is presented in this paper.

This paper describes performance characteristics of a bridge‐connected magnetic circuit with single output winding in dc control. The difference between positive and negative amplitudes of output current changes with the dc control current. An application of the bridge‐connected magnetic circuit to a dc current detector is presented in this paper.

This paper describes frequency characteristics of the bridge-connected magnetic circuit with parallel output winding. The control characteristics for various supply frequencies are calculated under simple assumptions. An application of the magnetic circuit to a power controller is presented in this paper.

This paper describes an analysis of the amorphous bridge-connected magnetic circuit in ac control. The value of output current is easily controlled by the phase difference between the control current and the supply voltage. The calculated values of the output characteristics agree well with the experimental ones.

The operating characteristics under ac control of a bridge-connected magnetic circuit, consisting of an amorphous toroidal magnetic core and a U-shape core were analyzed. The centerpiece was ac-driven and the output current agreed well with the calculated current. In particular, the output current may be controlled by varying the phase angle of the ac control current in the range from O° to 180°. A theoretical analysis in some detail is presented.