JPS60200764A - 2-power source dc/dc converter - Google Patents

Abstract

PURPOSE:To separate an insulator between a main power source and the secondary battery and to reduce the variation in a load supplying voltage by using a stepup transformer of the quarternary winding, and connecting windings with the main power source, the secondary battery discharging circuit, the secondary battery charging circuit and a load. CONSTITUTION:A rectifier 20 to become a main power source and a DC power source circuit 30 which includes the secondary battery are connected through a DC/DC converter 10 with a load 40. The converter 10 includes a stepup transformer 100 of the quarternary winding, the primary winding is connected with the main power source, the secondary winding is connected with the load 40, the tertiary winding is connected with the secondary battery, and the quarternary winding generated at the voltage higher than the charging voltage of the secondary battery is connected together with a reverse blocking element 122 with the secondary battery. The voltage of the main power source is monitored by a voltage divider 141, and when the malfunction decreases, a switch 112 connected in series with the tertiary winding is operated to supply the power of the secondary battery to the load 40.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field to which the Invention Pertains) The present invention relates to a DC-DC converter that uses a four-turn green transformer and has two power sources, one for use and one for non-use.

[Description of prior art]

There are a wide variety of applications for power supply devices that receive power from commercial power sources and bank amplifier batteries. Examples of this application include dual AC/DC power supplies for portable radios and televisions, i-sources for measuring instruments and data transmission processing equipment, and large-scale emergency power supplies that supply power to building equipment.

As a conventional device of this type, a floating charging type secondary battery device is often used. In this device, since the terminal voltage of the secondary battery differs significantly between charging and discharging, there is a drawback that a voltage regulator must be provided on the load side separately from the power supply device. Furthermore, when it is necessary to insulate the commercial power supply circuit from the load equipment connected to this device, there is a drawback that a separate isolation device from this device must be provided.

[Object of the Invention] The present invention eliminates the above-mentioned drawbacks, and aims to provide a dual-power DC power supply that can supply electric power with little voltage fluctuation to the load connected to this device while being insulated and separated from the commercial power supply circuit. The purpose is to provide a DC converter.

[Key points of the invention]

The present invention provides a first DC power terminal to which a main power source is connected;
A first switching element that switches on and off the current of the first DC power supply terminal, which includes a second DC power supply terminal to which a secondary battery is connected, and a load terminal, and a current that is interrupted by the first switching element. A step-up transformer that supplies the primary winding, a rectifier circuit that rectifies the current in the secondary winding of the step-up transformer and supplies it to the load terminal, and a second DC power supply terminal that opens and closes the current of the second DC power terminal. a switching element, a tertiary winding of the step-up transformer to which current is supplied intermittently by the second switching element, a first control circuit that controls the first switching element, and a second switching element; When power supply voltage is supplied to the second control circuit that controls the element and the first DC power supply terminal,
and an automatic control means for operating the first control circuit and operating the second control circuit when the power supply voltage disappears at the first DC power terminal. A quaternary winding that generates a voltage higher than the charging voltage of the secondary battery is provided, and the quaternary winding is connected to the second terminal via a backflow prevention diode.

Further, it is preferable that the first and second control circuits are connected so that their operating power supply current is supplied from the second terminal.

[Explanation based on examples]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be explained with reference to the drawings.

FIG. 1 is a block configuration diagram showing the configuration of the apparatus of this embodiment. Further, FIG. 2 is a waveform diagram showing waveforms of each part of the device of this embodiment.

First, the configuration of this embodiment device will be explained based on FIG. In this embodiment, the device is referred to as a two-power DC-DC converter (hereinafter referred to as DC-1) C converter according to the present invention.

) 10 and a rectifying and smoothing circuit (hereinafter referred to as a rectifier) 20
, a DC power supply circuit 30 , a load 40 , and a first switch 45 . Here, the DC-DC converter 10 includes a step-up transformer 100 having a quaternary winding, and a first switching element i.
ll, the second switching element 112, the first backflow prevention diode (hereinafter referred to as the first diode) 121, the second backflow prevention diode (hereinafter referred to as the second diode) 122, and the rectifier. Diode 12 as a circuit
3, a first control circuit 131, and a second control circuit 132
, a first voltage divider 141 , a second voltage divider 142 , a negative logic element 150 , and a second switch 160 . The rectifier 20 is connected to an external AC commercial power source to serve as a main power source, and the DC power supply circuit 30 includes a secondary battery.

The first switching element 111 and the second switching element 112 are transistors.

The output of the rectifier 20 is connected to the first DC power supply terminal of the DC-DC converter 10, and the output of the DC power supply circuit 30 is connected to the DC-DC power supply terminal.
The second DC power supply terminal Q of the DC converter 10 is connected to
A load terminal of the C-DC converter 10 is connected to an input of a load 40 via a first switch 45.

Further, the first DC power supply terminal of the DC-DC converter 10 is connected to one terminal of the primary winding 101 of the step-up transformer 100 and the input of the first voltage divider 141.
A first output of 41 is connected to an enable signal terminal of the first control circuit 131 and a negative logic element 150, an output of the negative logic element 150 is connected to an enable signal terminal of the second control circuit 132, and the first output of the negative logic element 150 is connected to an enable signal terminal of the second control circuit 132. The second output of the voltage divider 141 is connected to a common potential. Further, the second DC power terminal of the DC-DC converter 10 is connected to one terminal of the third winding 103 of the step-up transformer 100, one terminal of the fourth winding 104, and the second switch 160. , the second switch 160 is connected to the control power terminal of the first control circuit 131 and the control power terminal of the second control circuit 132.

The other terminal of the first winding 101 of the step-up transformer 100 is connected to the anode of the first diode 121, and the cathode of the first diode 121 is connected to the collector of the first switching element 111. The base of the element 111 is connected to the first control signal terminal of the first control circuit 131, and the emitter of the first switching element 111 is connected to the first control signal terminal of the first control circuit 131.
31 second control signal terminal and a common potential. Further, the other terminal of the fourth winding 104 of the step-up transformer 100 is connected to the cathode of the second diode 122, and the anode of the second diode F'122 is connected to the common potential. Furthermore, the third winding 1 of the step-up transformer 100
03 is connected to the collector of the second switching element 112, the base of the second switching element 112 is connected to the first control terminal of the second control circuit 132, and the base of the second switching element 112 is connected to the first control terminal of the second control circuit 132. The emitter is connected to a second control signal terminal of second control circuit 132 and a common heavy metal.

One terminal of the second winding 102 of the step-up transformer 100 is connected to the anode of the diode 123.
The cathode of 23 is connected to the load terminal of the DC-DC converter 10, the other terminal of the second winding 102 of the step-up transformer 100 is connected to a common potential, and the cathode of the diode 123
The cathode of is connected to the input of the second voltage divider 142, and the first output of the second voltage divider 142 is connected to the first control circuit 131.
and the sense signal terminal of the second control circuit 132, and the second output of the second voltage divider 142 is connected to a common potential.

Next, the operation of this embodiment device will be explained based on FIGS. 1 and 2. Here, the waveform diagrams (1) to (4) in FIG.
5) to (7) show the waveforms at the time of input from the DC power supply circuit 30 including the secondary battery, and (1) shows the waveform at the time of input from the first switching element 1.
11, (2) is the waveform of the base voltage of the first switching element 1.
(3) is the waveform of the cathode voltage of the second diode 122, (4) is the waveform of the anode voltage of the third diode 123, and (5) is the waveform of the second opening/closing voltage. (6) is the waveform of the base voltage of the element 112, (7) is the waveform of the collector voltage of the second switching element 112.
shows the waveform of the anode voltage of the third diode 123.

Here, when the output voltage of the DC power supply circuit 30 maintains the specified value, the first switching element 111 is in a conductive state and the step-up transformer continues to accumulate magnetic energy. The primary winding 101 and the tertiary winding 103 of the step-up transformer are connected so that the collector of the second switching element 112 does not take a negative value until the second switching element 111 becomes non-conductive and the handover fly hack period begins. The winding ratio between the

There are two types of normal operation of this DC-DC converter 10. The first normal operation mode is when the main power voltage is established via the rectifier 20, and in this case, power is supplied to the load 40 and the secondary battery included in the DC power supply circuit 30 is charged. done at the same time. In the second normal operation mode, when the main power supply voltage drops abnormally, in this case, power is continuously supplied to the load 40.

During these two types of normal operations, both the first switch 45 and the second switch 160 are closed. Further, the selection of the first normal operation mode and the second normal operation mode is determined depending on whether the voltage value of the AC voltage that supplies power to the rectifier 20 is equal to or higher than a specified value.

However, if this voltage value is higher than the specified value, the voltage signal applied to the enable terminal of the first control circuit 131 via the voltage divider 141 causes the first control circuit 131 to be activated.
is in the operating state, and this voltage signal is further applied to the enable terminal of the second control circuit 132 via the negative logic element 150, causing the second control circuit 132 to become inactive, and the first control circuit 132 to be in the inactive state. The circuit is in a state where the normal mode of operation can be performed.

Further, when the voltage value of the AC voltage that supplies power to the rectifier 20 is less than the specified value, the first control circuit 131 becomes inactive, while the second control circuit 132 becomes active, The circuit is in a state where a second normal mode of operation can be performed.

First, in the first normal operation mode, the first control circuit 131
The magnetic energy of the first winding 101 of the step-up transformer 100 accumulated during the conduction period of the first switching element 111 controlled by the control signal of this first switching element 111
becomes non-conductive, the third diode 123 is connected via the second winding 102, the second diode 122 is connected via the fourth winding 104, or the third diode is connected via the second winding 102. diode 123 and the fourth winding 104 to the second diode 122 . In the circuit including the second diode 122, the distributed power charges the secondary battery included in the DC power supply circuit 30, while in the circuit including the third diode 123, the distributed power charges the secondary battery included in the DC power supply circuit 30. Power is supplied to the load 40 via one switch 45 .

When the first switch 45 is operated to the open state in this first normal operation mode circuit state, all the power output from the rectifier 20 is consumed for charging the secondary battery included in the DC power supply circuit. .

Also, I) the voltage value of the load terminal of the C-DC converter 10 is detected, and a signal corresponding to this is sent to the first control circuit 1.
31 and a second control circuit 132, where a charging control signal is generated to perform charging control of the secondary battery in the circuit state of the first normal operation mode.

Next, in the second normal operation mode, power is supplied from the DC power supply circuit 30. In this case, the second control circuit 132
The third winding 103 of the step-up transformer accumulated during the conduction period of the third switching element 112 controlled by the control signal of
The magnetic energy is supplied to the third diode 123 via the second winding 102 when the second switching element 112 becomes non-conductive. In the circuit including the third diode 123, this supplied power is transferred to the first switch 45.
Power is supplied to the load 40 via. In this case, voltage is induced in the first winding 101 and the fourth winding 104, but power is not distributed due to the backflow prevention operations of the first diode and the second diode, respectively.

In this example device, the control circuit is composed of a first control circuit 131 and a second control circuit 132.
The present invention can be implemented even if the control circuits are combined into two control circuits.

Further, the present invention can also be implemented by using a voltage corresponding to the voltage at the second DC power supply terminal as the detection voltage for executing charging control of the secondary battery that is being supplied with power to the load 40.

〔Effect of the invention〕

As explained above, the present invention allows charging control to be freely set like Seiko's float type DC power supply, so the life of the secondary battery is maintained and automatic switching between the commercial power supply and the secondary battery is achieved. can be executed continuously in time. Furthermore, since the voltage fluctuation rate of the voltage applied to the load is extremely poor, there is no need to provide a voltage regulator on the load side separately from the power supply circuit, and therefore the installation conditions for devices serving as the load are relaxed. Furthermore, since the commercial power supply circuit and the load circuit can be insulated and separated by the step-up transformer, there is no concern that leakage current from the commercial power supply circuit will enter the load circuit.

Therefore, it can be used as a stabilized uninterruptible power supply for medical equipment, etc., which requires safety, and a remarkable effect can be produced.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing the configuration of an apparatus according to an embodiment of the present invention. The 20th is a waveform diagram showing voltage waveforms of main parts of the device according to the embodiment of the present invention. 10... DC-DC converter, 20... Rectifier, 30
...DC power supply circuit, 40...Load, 45.160.
...Switch, 100...y pressure 1 to lance, 111.
112...Switching element, 121.122.123...
Diode, 131.132... Control circuit, 141.
142...Voltage divider, 150...Negation logic element. Naotaka Ide, patent attorney and agent for patent applicant Yokogawa Medical Systems Co., Ltd.

Claims (1)

[Claims] (11) comprising a first DC power terminal to which a main power source is connected, a second DC power terminal to which a secondary battery is connected, and a load terminal; a first switching element that switches on and off the current; a step-up transformer whose primary winding is supplied with the current that is intermittent by the first switching element; and a step-up transformer that rectifies the current in the secondary winding of the step-up transformer and the load terminal. a rectifier circuit that supplies the current to the second DC power supply terminal; a second switching element that switches on and off the current of the second DC power terminal; and a tertiary winding of the step-up transformer to which the current that is interrupted by the second switching element is supplied. When sufficient power supply voltage is supplied to the first control circuit that controls the first switching element, the second control circuit that controls the second switching element, and the first DC power terminal, , an automatic control means for operating the first control circuit and operating the second control circuit when the power supply voltage of the first DC power supply terminal becomes insufficient or disappears, The step-up transformer is provided with a quaternary winding that generates a voltage higher than the charging voltage of the secondary battery, and the quaternary winding is connected to the second terminal of "2" through a backflow prevention diode. (2) The first and second control circuits are connected so that the operating power supply current is supplied from the second terminal. Dual power DC DC converter.