JP3470511B2 - Capacitor charger - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a capacitor charging device for periodically charging a load capacitor to a set voltage. 2. Description of the Related Art A first stage capacitor (load capacitor) of a magnetic compression power supply used as a power supply for an excimer laser stepper is charged periodically and repeatedly. FIG. 3 shows a circuit of the capacitor charging device. In the figure, INV1 is an inverter for initial charging (hereinafter simply referred to as INV1).
The primary winding P of the capacitor C1 and reactor L1 and the step-up transformer T1 for resonance is connected in series between the output terminals a _1, b _1, alternately switching elements S1, S2 in accordance with the resonance frequency of C1, L1 By switching to
Operates as a resonant inverter. [0003] INV2 is a sign adjustment inverter (hereinafter simply referred to as INV2), which includes a resonance capacitor C2, a reactor L2, and a step-up transformer T2 between output terminals a ₁ and b _1.
Are connected in series, and alternately switch the switching elements S3 and S4 in accordance with the resonance frequencies of C2 and L2, thereby operating as a resonance inverter. The secondary side S of each of the transformers T1 and T2
Rectifier RF1, RF to charge the load capacitor C ₀ is the
2 are connected. INV2 is set so that the switching frequency is higher and the charging voltage per operation is lower than INV1 . As shown in FIG. 4, the charge of the load capacitor C _O is started by operating the INV 1 for initial charging to rapidly charge the load capacitor C _O to a voltage V ₁ close to the target voltage V _CO, and to stop the INV 1. At the same time, the fine adjustment INV2 is operated to perform the fine adjustment charging so that the load capacitor C _O becomes the target voltage V _CO at a slightly lower charging rate. Since it is necessary to repeatedly charge the load capacitor C _{O at} a high speed, the target voltage V _{CO of the} load capacitor is required.
And the above voltage V ₁ is set, the DC voltage of the power supply E and the charging voltage of the load capacitor C _O are detected, and IN is set by the CPU.
The operation of V1 and INV2 is controlled. (For example, Japanese Patent Application Hei 8-1
No. 22095). [0007] The above-mentioned conventional capacitor charging device is uneconomical and requires a large device because two sets of transformers and rectifiers are provided for charging the load capacitor. [0008] The present invention has been made in view of the above problems, and an object of the present invention is to provide a capacitor charging device that can be reduced in size and inexpensive. According to the present invention, there is provided a capacitor charging apparatus comprising: a semiconductor device similar to a main circuit of a three-phase inverter;
First, second, and third serial arms,
3 series arms and a first series resonance circuit.
Switch to the frequency determined by the first series resonance circuit.
An initial charging inverter for performing the switching;
And a second series resonance circuit.
Switch according to the frequency determined by the two series resonant circuits.
Inverter for adjusting the pitch, which performs switching, and for initial charging
Input the resonance output of the inverter and the inverter for fine adjustment.
Step-up transformer and rectify the output of this step-up transformer
And a rectifier that charges the load capacitor.
It is a sign. According to each of the above-described devices, the number of transformers and rectifiers, which conventionally required two each, is reduced to one each. Embodiment 1 FIG. 1 shows a circuit of a capacitor charging device. In the figure, INV1 and INV2 are inverters for initial charging and charging adjustment, C1 and L1 and C2 and L2 are INV1 and I
An NV2 resonance capacitor and a reactor, T3 is a step-up transformer having _two primary windings P ₁ and P _2, and a winding P1
Is connected in series between the output terminals a ₁ and b _{1 of} INV1 together with the capacitor C1 and the reactor L2, and the winding P2 is connected to the output terminal a of INV2 together with the capacitor C2 and the reactor L2.
It is connected between the _2, b _2. RF3 is the transformer T3 2
A rectifier for charging the load capacitor C _O connected to the next winding S. With the above configuration, INV
When the switching elements S1 and S2 are alternately switched in accordance with the resonance frequencies of C1 and L1, INV1 operates as a resonance inverter, and the transformer T3 and the rectifier R
The load capacitor C _O is charged via F3. Similarly I
When the switching elements S3 and S4 of NV2 are alternately switched according to the resonance frequencies of C2 and L2, INV
2 operates as a resonant inverter, and charges the load capacitor C _O via the transformer T3 and the rectifier RF3. [0014] Thus, the INV1 and INV2 By operating as shown in FIG. 4, it is possible to conventional similarly charged fast and accurately load capacitor C _O to the target voltage V _CO. According to this embodiment, the conventional two
Since only one transformer and one rectifier are required, the apparatus can be reduced in size and inexpensive. Embodiment 2 FIG. 2 shows a circuit of a capacitor charging device. In the figure, INV3 is an inverter for initial charging and fine adjustment, and is a switching element S1-S having diodes connected in anti-parallel.
6 is composed of three series arms like the three-phase inverter, and the first series arm (S
, S4) and the third series arm (S3, S6) as an initial charging inverter,
2, S5) and the third series arm (S3, S6) are used as a fine adjustment inverter. [0017] C1 and L1 and C2 and L2 capacitor and a reactor for the series resonance, T4 for the boost transformer, a resonant C1, L1 is the first series arm (S1, S4) an output terminal a ₁ and the transformer T4 the primary winding is connected between one end of the P _1, the resonant C2, L2 the second series arm (S2,
Is connected between one end of the output terminal a ₂ and the primary winding P ₁ of S5), the other end of the primary winding P ₁ and the third series arm (S
3, S6). RF3 in the rectifier are connected to output by rectifying the output of the secondary winding S of the transformer T4 to the load capacitor C _O. With the above configuration, INV
3 switching elements S1, S6 and S3, S4 to C1,
When switching is performed alternately in accordance with the resonance frequency of L1, the initial charging inverter composed of the elements S1, S4, S3, and S6 operates as a resonance inverter, and charges the load capacitor C _O via the transformer T4 and the rectifier RF3. . Similarly, switching elements S2, S5 and S3, S
6 is switched alternately in accordance with the resonance frequencies of C2 and L2, the inverter for adjusting the sampling composed of the elements S2, S5, S3 and S6 operates as a resonance inverter, and the load capacitor C is connected via the transformer T4 and the rectifier RF3. _O
Charge. [0019] Thus, the initial charging inverter and fine adjustment inverter by operating as shown in FIG. 4, it is possible to conventional similarly charged fast and accurately load capacitor C _O to the target voltage V _CO . According to this embodiment, since there is only one inverter, transformer and rectifier, the device can be further reduced in size and inexpensive. According to the present invention, since the number of transformers and rectifiers constituting a circuit is one, it is economical, and the apparatus can be made inexpensive and small.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram of a capacitor charging device according to a first embodiment. FIG. 2 is a circuit diagram of a capacitor charging device according to a second embodiment. FIG. 3 is a circuit diagram of a conventional capacitor charging device. FIG. 4 is a graph illustrating a switching time. [Description of References] INV1… Inverter for initial charging INV2… Inverter for fine adjustment INV3… Inverters C1 and C2 for initial charging and charging adjustment… Resonance capacitors L1 and L2… Resonance reactors TR1 to 4 ... ... Rectifier C _O ... Load capacitors S1 to S6 ... Switching element E ... DC power supply for inverter.

Continuation of the front page (51) Int.Cl. ⁷ identification code FI H02M 7/48 H01S 3/097 A (56) References JP-A-3-253258 (JP, A) JP-A 8-186981 (JP, A JP-A-7-322611 (JP, A) JP-A-2-139487 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) 00 H02M 3/335 H02M 7/48

Claims (1)

(57) [Claims] [Claim 1] Semiconductor same as main circuit of three-phase inverter
It has first, second, and third series arms
And the first and third series arms and the first series resonance circuit.
And a frequency determined by the first series resonance circuit.
Inverter for initial charging that switches according to
And second and third series arms and a second series resonance circuit.
To the frequency determined by the second series resonance circuit.
And the inverter for initial charge and the inverter for fine adjustment.
The boost transformer to which the vibration output is input, and the output of this boost transformer is rectified to charge the load capacitor.
Capacitor charging device comprising a rectifier, in that it consists of electricity.