JPH04331420A - Power source circuit - Google Patents

Abstract

PURPOSE:To raise a step-up ratio by using a component having a low withstand voltage. CONSTITUTION:One primary winding 12 and, secondary windings 141, 142, 143,..., 14n which are not connected to each other, are provided in a transformer 10. Rectifiers 201, 202, 203,..., 20n are respectively connected to the secondary windings, and connected in series with each other. Since a voltage obtained by integrating voltages output from the respective rectifiers is generated at both ends of a circuit in which the n pieces of the rectifiers are connected in series with each other, a turn ratio of the transformer can be reduced. Thus, the rectifiers can be formed of components each having a low withstand voltage.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a power supply circuit that is connected to a capacitive load such as an electrode part of a vibration damping device or a power transmission device using an electrorheological fluid, and applies a voltage to the capacitive load. The present invention relates to a power supply circuit used to apply and cut off the applied voltage, or to change the applied voltage continuously or stepwise.

0002

[Prior Art] Conventionally, electrorheological fluid applied devices such as vibration damping devices and power transmission devices utilize the viscosity of the electrorheological fluid by interposing an electrorheological fluid between electrodes and applying a voltage to the electrorheological fluid. It has been known. As the power supply circuit of this device, a power supply circuit consisting of a transformer and a rectifier circuit connected to the secondary winding of the transformer and provided with a capacitor and a diode is used. The responsiveness of the electrorheological fluid itself (the time from when a voltage is applied until the orientation of the molecules is completed and the viscosity becomes constant) is said to be several milliseconds or less, and in order to make the most of this characteristic, The response of the power supply circuit needs to be high-speed response of several milliseconds or less, preferably about 500 μsec or less.

[0003] Furthermore, when this electrorheological fluid application device is mounted on a vehicle, it is necessary to boost the voltage of the vehicle battery (12V) to about several KV to tens of KV, so a power supply circuit with a high boost ratio is required. It becomes necessary. Conventional techniques for improving the step-up ratio include increasing the turns ratio (secondary windings/primary windings) of the transformer and increasing the voltage doubling degree of the rectifier circuit.

0004

However, in the above-mentioned conventional technology, it is necessary to increase the withstand voltage of the parts constituting the transformer and the rectifier circuit, and it is also necessary to increase the voltage multiplier of the rectifier circuit, resulting in high costs and This leads to lower response speed and
A problem arises in that efficiency decreases.

The present invention was made to solve the above problems, and by making it possible to use components with low breakdown voltage and high response speed, that is, low loss, for the same boost ratio. , we have created a power supply circuit that can make the response of the power supply faster, increase efficiency, and reduce costs.Also, for the same cost, we can create a power supply circuit that can make the response of the power supply faster, increase efficiency, and increase the step-up ratio. The purpose is to provide.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a transformer including a primary winding and a plurality of secondary windings that are not interconnected; a plurality of rectifier circuits connected to each other and connected in series with each other;
It is composed of:

[0007]

The transformer of the present invention includes a plurality of secondary windings that are not interconnected. Therefore, when an alternating current or pulsating voltage is applied to the primary winding, an induced voltage is generated in each of the secondary windings. Since a rectifier circuit is connected to each of the secondary windings, the voltage induced in the secondary windings is converted into direct current by the rectifier circuit. Furthermore, since the rectifier circuits are connected in series, a voltage is generated across both ends of the series circuit, which is the sum of the DC voltages output from each of the rectifier circuits. That is, a voltage is generated whose magnitude corresponds to the number of secondary windings (rectifier circuits). Therefore, the primary winding and one
Even if the turns ratio with the secondary winding is made small and the voltage doubler of the rectifier circuit is made small, a voltage proportional to the number of secondary windings, that is, the number of rectifier circuits, will be generated from both ends of the series circuit. Therefore, the step-up ratio can be increased by decreasing the turns ratio of the transformer and the voltage doubler ratio of the rectifier circuit. This allows components such as diodes and capacitors that make up the rectifier circuit to be configured with components with low withstand voltage, that is, components with fast response speed and low loss, improving the response of the power supply and increasing efficiency. , it is possible to achieve cost reduction.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows this embodiment, and a step-up transformer 10 of this embodiment has one primary winding 12 and n secondary windings 141, 142, 14 which are not connected to each other.
3,..., 14n. An AC converter 16 composed of an inverter or the like is connected to the primary winding 12 of the step-up transformer 10. A DC power supply 18 is connected to this AC converter 16 . step-up transformer 10-2
Next winding 141, 142, 143,..., 14n
Each of the rectifier circuits 201, 202, 203
, ..., 20n are connected to each other. One output terminal of the rectifier circuit 201 is connected to the capacitive load 22, and the other output terminal is connected to one output terminal of the rectifier circuit 202. The other output terminal of the rectifier circuit 202 is connected to one input terminal of the rectifier circuit 203.
The other output terminal of 3 is connected to one output terminal of the rectifier circuit 204, and the following are similarly connected to the rectifier circuit 201,
202, 203, . . . , 20n are connected to each other in series. The other output end of the rectifier circuit 20n is connected to a capacitive load 22, and the voltage detector 24 is connected between one output end of the rectifier circuit 201 and the other output end of the rectifier circuit 20n. . This capacitive load 22 includes a capacitive component 42 and a resistive component 44. The output end of the voltage detector 24 is connected to a comparator 26 in which an output voltage set value is set. The output end of the comparator 26 is connected to the AC converter 16 via a voltage control circuit 28 that controls the voltage by pulse width modulation or the like.

The rectifier circuit 201, as shown in FIG.
It consists of a triple voltage rectifier circuit. This triple voltage rectifier circuit is composed of diodes 301, 321, 341 and capacitors 361, 381, 401. Note that the rectifier circuits 202, 203, . . . , 2
0n also has the same configuration, so the same parts are given corresponding symbols and their explanation will be omitted.

According to this embodiment, when alternating current is applied from the alternating current converter 16 to the primary winding 12, the secondary windings 141, 1
A voltage is induced in each of the rectifier circuits 201, 202, 203, .
. , 20n and applied to the capacitive load 22. In addition, rectifier circuits 201, 202, 20
The voltage output from the series circuit consisting of 3, .
8, the output voltage is feedback-controlled to the set output voltage value.

In this embodiment, n
A rectifier circuit is connected to each secondary winding using two secondary windings, and the rectifier circuits are connected in series with each other. Therefore, the voltage generated across this series circuit is the sum of the voltages output from each rectifier circuit. Assuming that the outputs of each rectifier circuit are the same voltage, in order to obtain the same step-up ratio as before,
The winding ratio of one secondary winding may be 1/n. Further, the voltage doubler ratio of the rectifier circuit can also be lowered depending on the number of rectifier circuits used. Therefore, the diodes and capacitors that make up the rectifier circuit can be configured with ones with low withstand voltage, which improves response and efficiency.
Cost reduction and miniaturization can be achieved.

When the voltage applied to the capacitive load 22 is cut off, the capacitors 401, 402, 403
, . . . , 40n, the charge stored in the capacitive component 42 is discharged via the resistive component 44. In this embodiment, in order to speed up this discharge response, the capacitor 4 is
The capacitances C1, C2, C3,..., Cn of 01, 402, 403, . . . , 40n are determined to satisfy the following equation.

[0013]

[Formula 1] Note that when all capacitances are set to the same value Cc, the following equation is obtained.

[0014]

[Formula 2] However, C2 is the capacitance of the capacitive component 42 of the capacitive load 22, R is the resistance value of the resistive component 44, and (C1+C2
)R represents the discharge time constant. This K is several msec
It is preferably 500 μsec or less, C2 is 150PF, and R is about 2MΩ. As described above, according to this embodiment, the capacitance of the capacitor contributing to the discharge of the rectifier circuit is determined so that the discharge time constant is equal to or less than a predetermined value, so that the discharge response can be made faster.

FIG. 3 shows rectifier circuits 201, 202, 20.
Another example of 3,..., 20n is shown below. These rectifier circuits are comprised of double voltage rectifier circuits. This double voltage rectifier circuit is composed of diodes 461, 481 and capacitors 501, 521. In addition,
Since the rectifier circuits 202, 203, .

Furthermore, when a double voltage rectifier circuit is used, the capacitors 501, 521, 502, 522,
..., 50n, 52n capacitance C1, C1
',C2,C2',C3,C3',...,C
n and Cn' may be determined to satisfy the following formula.

[0017]

[Formula 3] Note that when all the capacitances are set to the same value C0, the following equation is obtained.

[0018]

[Equation 4] This example is suitable for an in-vehicle electrorheological fluid application device that boosts the voltage from 12V to several KV to tens of KV because it is possible to increase the boost ratio by using parts with low withstand voltage. There is.

[0019] In the above, an example was explained in which DC is converted to AC and applied to the primary winding of the transformer, but AC may also be applied directly to the primary winding, or pulsating voltage may be applied. You may also do so.

Next, a specific example of the above-mentioned capacitive load will be explained with reference to FIG. This specific example relates to a vehicle suspension that combines a vibration damping device 60 and an air spring 62. The vibration damping device 60 includes cylindrical flexible membrane bodies 64, 6
It is equipped with 6. An end of a piston 68 is inserted into one end of each of the cylindrical flexible membrane bodies 64 and 66 to make them liquid-tight, and the cylindrical flexible membrane bodies 64 and 66 are connected by the piston 68. The other ends of the cylindrical flexible membrane bodies 64 and 66 are made liquid-tight by metal face plates 70 and 72, respectively, thereby forming a sealed chamber 74 within the cylindrical flexible membrane bodies 64 and 66. There is. The face plates 70 and 72 have a rod-shaped positive electrode 80 passing through the face plates 70 and 72 and a constriction passage 8 between the positive electrode 80 and the positive electrode 80 .
2 and a cylindrical negative electrode 78 , and are connected by a connecting member 76 that passes through the piston 60 and is guided by a guide member 65 . A portion of the connecting member 76 that passes through the face plate 72 is covered with a stopper 88 made of an elastic body. The positive electrode 80 and the load electrode 78 and the positive electrode 80 and the face plates 70 and 72 are insulated by an insulating material 84 made of synthetic resin, ceramics, etc., interposed between them. Further, holes 86 are formed near both ends of the negative electrode 78, and the holes 86 form a closed chamber 74 and a throttle passage 8.
2 are in communication. An electrorheological fluid is sealed in the sealed chamber 74 and the throttle passage 82.

A flange is formed on the outer periphery of the intermediate portion of the piston 60, and a bottomed cylindrical inner cylinder 90 is attached to this flange. An eye hook 92 is provided on the bottom surface of the inner cylinder 90 for attaching this device to a mounting site on a vehicle.

One end of an outer cylinder 94 is attached to the face plate 70. A flexible sleeve 96 is attached to the other end of this outer cylinder 94.
One end of the flexible sleeve 96 is airtightly attached, and the other end of the flexible sleeve 96 is airtightly attached to the outer periphery of the cylinder. Therefore,
An air chamber 98 is formed between the inside of the outer cylinder 94 and the inside of the inner cylinder 90.
will be constructed. The inside of the outer cylinder 94 and the inside of the inner cylinder 90 are communicated through a through hole 100 formed in the flange. An air spring is constructed by filling air in the air chamber 98.

The electrodes of the vehicle suspension vibration damping device constructed as described above are connected to the power supply circuit described above. At this time, since the voltage of the vehicle battery is 12V, the power supply circuit output is set to about 10KV.

[0024] Such a vibration damping device can exhibit a vibration damping function when no electric field exists between the electrodes, and when an electric field is generated between the electrodes, the viscosity of the electrorheological fluid increases the intensity of the electric field. The vibration damping force increases with the strength of the electric field, so by selecting the strength of the electric field, it is possible to exert a vibration damping force of the desired magnitude.

In the vibration damping device described above, the connecting member 7
6 can be placed outside the sealed chamber 74, but in order to downsize the device, the piston 60 can be passed through it and placed inside the sealed chamber 74, as shown in the figure. In this case, guiding the sliding movement of the connecting member 76 with respect to the piston 60 by the respective guide members 65 attached to the upper and lower end portions of the piston 60 makes the movement smooth. , and the connecting member 7
This is preferable in order to prevent the piston 3 from coming into contact with the piston 3.

Note that each guide member 65 does not require a liquid-tight seal between it and the connecting member 76, and a tight fit between the two can be avoided.
Actuation of the coupling member 76 by small forces can be made possible.

By the way, in this example, the throttle passage 82 in the connecting member is made into a cylindrical shape to provide the required cross-sectional area, but the shape can be changed as necessary to each cylinder shape, a columnar shape with an appropriate outline, etc. The constriction passage 82 thus formed can be modified by a hole 86 provided in each end portion of the connecting member 76 to connect the respective flexible membrane body 64, 6.
By opening on the inside of each flexible membrane body 6, the flow of the electrorheological fluid located inside each flexible membrane body 1 to the throttle passage 82 is ensured.

According to the vibration damping device constructed as described above, in addition to being able to increase the length of the throttle passage 82, the cross-sectional area of the passage can be made as small as required, and the risk of mutual contact between components can be avoided. Since it can be removed completely, the vibration damping function of the device can be improved as desired without any disadvantages.

[0029]

[Effects of the Invention] As explained above, according to this embodiment,
Since a rectifier circuit is connected to each of the multiple secondary windings that are not connected to each other, and these rectifier circuits are connected in series, it is possible to increase the step-up ratio using components with low withstand voltage, thereby reducing costs. Moreover, it is possible to provide a power supply circuit with high efficiency and high speed response.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the invention.

FIG. 2 is a circuit diagram of the rectifier circuit of FIG. 1;

FIG. 3 is a circuit diagram of the rectifier circuit of FIG. 1;

FIG. 4 is a sectional view showing an example of a load used in the above embodiment.

[Explanation of symbols]

60 Vibration damping device 62 Air spring

Claims (1)

[Claims] 1. A transformer comprising a primary winding and a plurality of secondary windings that are not interconnected; and a plurality of rectifier circuits connected to each of the secondary windings and connected in series with each other. , including the power supply circuit.