JP2005223867A - Stepup pulse power supply using magnetic energy regeneration switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply of a large pulse current which increases a starting current by generating a voltage higher than a power supply voltage in a charge storing capacitor and discharging it, using a magnetic energy regeneration switch. <P>SOLUTION: When a magnetic energy regeneration switch is driven with a continued on-pulse string which a pulse width is narrowed so as to supply a minor pulse current to a load with inductance connected to a power supply in series, during quiescent time of the load, a voltage develops and is stored in the charge storing capacitor. When the voltage is fully stepped up, a large current pulse is generated by driving the switch with a long on-pulse of the switch and discharging from the capacitor to the load quickly, and large power is obtained at the time of starting a device driven by electromagnetic force. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a power supply for supplying a pulse current.

  In a solenoid, solenoid valve, or motor driven by applying electromagnetic force of current, a load that excites the drive coil by turning on and off the voltage from the power source with a semiconductor switch, and the current can be regarded as a circuit of inductance L and resistance R The magnetic field is generated by flowing in the magnetic field, the magnetic energy is accumulated in the coil, and the driving force is generated to perform mechanical work outside.

  However, since there is an inductance, it takes time for the current to rise, and in order to speed it up, it is necessary to apply a high voltage. This is called the forcing voltage, and several times the voltage that maintains the steady current is applied, and this is called the forcing rate. In addition, when the work is finished and the driving force is maintained and the motor is stationary, for example, the current should be maintained at one third, but since there is no means for reducing the current, if the current continues to flow, Increases and coil heating problems arise.

In a power supply that sends a pulse current to a circuit with inductance, magnetic energy that can store the energy of the current that flows in the inductance when the current is cut off in the capacitor and recover the current by regenerating the capacitor energy to the load the next time it is turned on There is a regenerative switch. Since the necessary voltage is automatically regenerated from the inductance, it can be said that the power source of the equipment has only a voltage corresponding to the resistance, so that the power factor of the power source is good. The regenerative voltage is accumulated after the next time, and the voltage gradually rises in a time equivalent to the time constant of the circuit. Therefore, the expected effect is insufficient at the first pulse.
Patent Publication 2000-358359

  The problem to be solved by the invention is that, in a solenoid, a solenoid valve, a motor, etc. driven by applying an electromagnetic force of current, the driving force at the start time exceeds the static friction and resists the moment of inertia. As an electromagnetic drive system, it is important to design speed and efficiency as an electromagnetic drive system, and the power source is also required to increase the drive force at the start.

  When a magnetic energy regenerative switch is connected in series with a DC power supply to drive a load with inductance, the regenerative voltage compensates the voltage for the inductance after the next pulse, and the first time is accumulated in the capacitor. It was twice the power supply voltage.

  In the present invention, a magnetic energy regenerative switch is connected in series between the power source and the load, and current energy is accumulated at the time of turning on and off, and the load is regenerated without loss. This utilizes the effect that the energy flows in and the DC voltage of the capacitor rises indefinitely.

  The magnetic energy regenerative switch is connected in series between the power supply and the load with inductance, and the voltage is stored in the storage capacitor by repeating the on / off operation by ultrashort pulses, and finally the resistance of the load is changed to the power supply voltage. The capacitor voltage takes advantage of the phenomenon that the capacitor voltage rises higher than the power supply voltage until the divided current value is reached.

  The reason for this is that if the pulse time width of turning on the magnetic energy regenerative switch is made small here, the magnetic energy regenerative switch is turned off while the current rises, and the current value determined by the resistance cannot be obtained.

  Then, the voltage of the storage capacitor further increases until the current value determined by the resistance is reached. Here, conventionally, the role of the magnetic energy regenerative switch is that the storage capacitor absorbs the magnetic energy of the current and discharges it. It can be considered as a power factor correction device that automatically generates a voltage for compensating the power factor to 1.

  In other words, when the magnetic energy regenerative switch continuously generates a short on-pulse, a slight current pulse flows through the inductance and resistance of the load, and the voltage increases in the storage capacitor due to the off-state. Flows in.

  Similar to the operation of a flyback voltage raising circuit, the flyback method does not apply a voltage higher than the power supply voltage to the coil excitation, but this method has a switch in series with the circuit and the voltage of the storage capacitor is the power supply voltage. At the same time, it increases the current in the circuit, and as the voltage accumulates, the voltage rise is increasingly accelerated.

  The generated voltage is used for the next pulse generation. It has a feed-forward effect in which the generated voltage increases, and a bootstrap (a bootstrap famous as a method of walking in the sky while pulling a shoelace) circuit.

  A magnetic energy regenerative switch connected in series between the power supply and the load is applied to the switch with a short on-pulse train continuously during the system standby time, and the load gradually applies a voltage to the storage capacitor with a current that does not move. Raise. After that, when you want to actually move the electromagnetic drive device that becomes the load, applying a long on-pulse causes a large discharge current of the capacitor to flow to the load, and after the capacitor voltage becomes zero, the steady current determined by the power supply voltage is Flowing. A large driving force is obtained by the discharge current of the capacitor, and then a steady driving force is obtained.

  Since general electromagnetic driving force is required to be large at the time of starting and is often lower than that after that, starting current by magnetic energy regenerative switch can be obtained, so steady current becomes low current corresponding to the driving force of maintenance If it prepares, it will reduce the power consumption and the heat generation amount of the drive coil.

  FIG. 1 shows an embodiment, in which a DC regenerative switch 3 is inserted into a circuit in which a DC voltage power source 1 drives an electromagnetic relay 2 to form a switch. The control circuit 4 generates an on / off gate signal for the semiconductor switch. In the case of the embodiment, as shown in FIG. 1, a series of short pulses are continuously output as on pulses.

  The storage capacitor accumulates several times the power supply voltage in a continuous short pulse, but when sufficient voltage is generated, switching to the long pulse causes the current value to rise and the capacitor to discharge and load the load. A large current flows and a large driving force is generated.

  FIG. 1 shows an embodiment in which the load is 1 mH and the resistance is 5 ohms with a power supply voltage of 5 V. In the magnetic energy regenerative switch, since the current is unidirectional, the diode can be substituted for the diode 33. When the P-MOSFET 31 is used, there is an advantage that an external diode is omitted. A diode may be externally attached to the reverse conducting semiconductor switch. A short on-pulse train has 30 microseconds and a frequency of 10 kHz.

  FIG. 2 shows the result of the simulation calculation by the computer of this circuit, and the voltage rises to about 15 V in the storage capacitor 100 microfarad in 45 milliseconds. It can be seen that when the short on-pulse, which was 15 microseconds when the voltage has sufficiently increased to the target, is changed to 10 milliseconds long, the capacitor is fully discharged, and a current that is 2.5 times larger than the conventional current flows to the load.

  When the discharge ends, the current becomes about 1 A, which is a value determined by the voltage and resistance, and continues until the pulse ends. When the long pulse conduction ends, the short pulse continuous conduction mode is set, and the capacitor is charged again.

  If the inductance and resistance of the load are insufficient for this operation, the effect can be further increased by adding an additional inductance and an additional switch P-MOSFET 3 as shown in FIG. The switch is controlled to be turned on when the capacitor is charged and turned off when the capacitor is discharged.

  As a result, in any case of the inductance and resistance of the load, the pulse width and interval for determining the charging time and charging voltage of the capacitor can be determined, which is effective.

  FIG. 4 shows the result of the simulation calculation by the computer. The voltage due to the continuous short pulse rises to 50 V, and the peak current due to the long pulse discharge rises to A.

  When applied to an apparatus using pulsed electromagnetic force, it can be used to increase the pulling force at the start and increase the rotational force. However, if configured as in the second embodiment, the load can be determined from the power supply voltage in any case. Since a much higher voltage can be applied, a device that requires a high voltage at the beginning of starting, such as a discharge applied power supply, can be driven with a simple configuration called a switch.

  If the power supply for the relay circuit is used, even if the supply voltage is lowered, sufficient operation speed can be obtained, so that power consumption can be reduced.

1 shows Example 1 of a step-up pulse power supply according to the present invention. It is a figure which shows the simulation result of the current voltage waveform of the pressure | voltage rise pulse power supply Example 1 which concerns on this invention. 2 shows a step-up pulse power supply according to a second embodiment of the present invention. It is a figure which shows the simulation result of the current voltage waveform of the pressure | voltage rise pulse power supply Example 2 which concerns on this invention.

Explanation of symbols

10 Boost Pulse Power Supply 20 DC Voltage Source 30 Magnetic Energy Regenerative Switch 31 Semiconductor Switch (P-MOSFET)
32 Magnetic energy storage capacitor 33 Diode 40 Control means 50 Load inductance 60 Load resistance 70 Additional inductance 71 Additional semiconductor switch (P-MOSFET)

Claims (2)

A magnetic power regenerative switch that supplies a pulse current to an inductive load is connected in series, and is a pulse power source that is used as a supply current to the inductive load that switches the current,
The pulse power supply comprises a magnetic energy regenerative switch connected in series with a voltage source and a load, and a control means for sending a signal to a gate for on / off control of the switch, so that a weak current is energized for a short time during a load operation pause period. By repeating the above, a high voltage is generated in the energy storage capacitor of the magnetic energy regenerative switch, and the generated voltage is energized as a unit during the operation of the load. The auxiliary inductance is connected in series between the magnetic energy regenerative switch and the load, and the auxiliary switch is provided in parallel with the load, and the auxiliary switch is turned on during the idle period in which a high voltage is generated in the magnetic energy storage capacitor. 2. The magnetic energy storage capacitor is boosted by repeating short-time energization for boosting as described above by turning on / off the current flowing through the auxiliary inductance while not passing the current through the load. A pulse power supply device with a boosting function described in 1.

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