JPH036151Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to improvement of load fluctuation characteristics in a linking chain converter type multi-output DC stabilized power supply device.

(Prior Art) As a small capacity multi-output DC stabilized power supply device, for example, the one shown in FIG. 1 has been used in the past.

This device is derived from a linking chain yoke converter type DC stabilizing power supply circuit a, a main power supply part A and an output transformer T, which stabilizes the rectified output from the rectifier filter circuit RF by a series dropper type DC stabilizing circuit b. The sub-power supply unit is B1, which rectifies the output by rectifier filter circuits _RF1 and _RF2 , and stabilizes it by series dropper type DC stabilization circuits _b1 and _b2, respectively, to create _a slave output.
It consists of B ₂ . In the main power supply section A in Figure 1, Inv is the inverter circuit, T is the output transformer, _N1 is its primary winding, _N21 , _N22 , _N23 are the secondary windings, _Nc control winding, DV _s error voltage detection circuit,
CP is a control signal generation circuit. The detected error voltage output from the error voltage detection circuit DV _s by comparing the output voltage V _s with the reference voltage controls the control signal generation circuit CP via the phototransistor PT and photodiode PD forming a photocoupler, and the output voltage is The inverter circuit _Iov is controlled on and off so that _Vs remains constant. Further, Q is a control transistor, and DV _p is a voltage detection circuit, which controls the control transistor Q based on the detected voltage output to make the output voltage V _p constant. Next, in the sub power supply sections B ₁ and B ₂ , RF ₁ and RF ₂ are rectifying filter circuits, Q' and Q'' are control transistors, respectively, and DV ₀₁ and DV ₀₂ are voltage detection circuits, respectively. This stabilizes the voltages V ₀₁ and V ₀₂ .

(Problems with the Prior Art) By the way, such a multi-output DC stabilized power supply device is composed of a feedback-controlled channel, a so-called master output circuit, and other channels, which are not directly feedback-controlled, a so-called slave output circuit. Those that use the cross regulation method can reduce the size of the output transformer by making the on-off cycle of the inverter circuit I _ov faster, and at the same time, by using the cross regulation method, it is possible to construct a multi-output circuit at a low cost. Moreover, it has advantages such as low switching noise due to the series dropper type DC stabilization circuit.

However, on the other hand, it has the disadvantages of poor slave output fluctuations due to load fluctuations in the master output circuit, that is, cross regulation, and poor load fluctuation characteristics, that is, load regulation of the slave output circuit. There is a drawback that an error in the number of windings results in variations in the slave output circuit voltage.

The present invention eliminates the above-mentioned drawbacks and provides an inexpensive, highly stable multi-output DC stabilized power supply device with good regulation, which can be widely used as a power source for devices with different load conditions.
Next, the details will be explained using the drawings.

[Structure of the idea]

(Means for solving the problem) Figure 2 is a circuit diagram of the principle of the present invention (parts with the same symbols as in Figure 1 indicate equivalent parts), and the features of the present invention are as follows. . That is, unlike FIG. 1, error voltage detection circuits DV _s1 and DV s2 are provided not only in the main power supply section _A but also on each output shaft of the rectifying filter circuits RF ₁ and RF ₂ of each of the sub power supply sections B ₁ and B ₂ . and form power supply circuits A, A ₁ , and A ₂ with the same configuration, and add their respective detected error voltages to an AND circuit (AND circuit) LO to obtain an AND, thereby controlling the inverter circuit I _ov. It is characterized by the following.

(Functions and Effects) As is well known in the linking chain converter type DC stabilized power supply circuit, when the output voltage V _s rises above the set value, the control signal generation circuit
CP operates to control the on/off period of the inverter circuit _Iov to return the output voltage _Vs to the set value.
Conversely, when the output voltage V _s drops below the set value, the feedback control system becomes an open loop and feedback control is no longer performed, so the inverter circuit I _ov changes to the output voltage
Operates to raise V _s to the set value.

Therefore _, as in the circuit of the _present invention shown in FIG.
When the control signal generation circuit CP is configured to be controlled by the AND output of DV _s , DV _s1 , and DV _s2 ,
When the output voltages of the rectifier filter circuits RF, RF ₁ , and RF ₂ fall below the specified values, the control system of the DC stabilized power supply circuit becomes an open loop and works to increase the output voltage, and this operation causes a voltage drop. When the output voltage of the power supply unit returns to the set value, it is stopped.

Therefore _, the emitters _and
Set the voltage drop between the collectors to the minimum voltage that can be stably controlled, and calculate each voltage drop at that time as △V _F ,
At the same time as △V _F1 and △V _F2 , each rectified output voltage V _s ,
V _s1 , V _s2 as V _s =V ₀ +△V _F ,Vs ₁ =V ₀₁ +△V _F1 ,
Set V _s2 = V ₀₂ +△V _F2 . Then the output voltage
If even one channel of V _s , V _s1 , and V _s2 falls below the set value, the control unit CP of the DC stabilized power supply circuit
The inverter circuit I _ov is boosted and controlled, so that the voltage drop between the emitter and collector of each control transistor is not reduced. Therefore, all channels have a minimum output voltage guarantee function,
Stabilized output voltages V ₀ , V ₀₁ , and V ₀₂ can be obtained.

In addition to this, the output voltages Vs, Vs ₁ and Vs ₂ decrease as the load becomes heavier, so the voltage drop between the emitter and collector of the control transistor of each series dropper type DC stabilizing circuit becomes smaller. Therefore, the collector loss of the channel with the reduced output voltage works advantageously even under heavy load conditions, and the loss is smaller than that of the conventional cross regulation system.

As a result, the present invention takes advantage of the advantages of the compact, low-noise, and inexpensive cross-regulation method that consists of a DC stabilizing power supply circuit and a series dropper type DC stabilizing circuit, while also influencing the magnitude of the load for each output channel. Therefore, it is possible to provide a low-loss DC stabilized power supply circuit that can obtain a highly stabilized output voltage without being affected.

(Embodiment) Fig. 3 is a circuit diagram of an embodiment of the present invention using a linking chain converter type DC stabilized power supply circuit, in which T is the output transformer, N ₁ is the primary winding, and N ₂₁ is the output transformer. , N ₂₂ , N ₂₃ are the secondary windings, N _c is the control winding, Q ₁ is the main switching transistor, D ₁ , D ₂
is a diode, _C1 is a capacitor, _R1 , _R2 , and _R3 are resistors, and these form an inverter circuit _Iov .
Q ₂ is a control transistor, C ₂ is a capacitor, R ₄ is a resistor, and D ₃ is a diode, which together form a control signal generation circuit CP. D ₄ , D′ ₄ , D″ ₄ are diodes, C ₃ , C′ ₃ , C″ ₃ are capacitors, and these form rectifier filter circuits RF, RF ₁ , RF ₂ . R ₅ , R′ ₅ , R″ ₅ and R ₆ , R′ ₆ , R″ ₆ and R ₇ ,
R′ ₇ and R″ ₇ are resistors, and SR, SR′, and SR″ are shunt regulators, and these constitute the error voltage detection circuit.
PD, PD′, and PD″ forming DV _s , DV _s1 , and DV _s2 are photodiodes, and PT, PT′, and PT″ are phototransistors.
PC′, PC″ are formed, phototransistors PT,
The emitters and collectors of PT′ and PT″ are connected in series to form error voltage detection circuits DV _s , DV _s1 ,
The logical product of the outputs of DV _s2 is taken to control the control signal generation circuit CP, and the linking chain yoke converter DC stabilized power supply circuit a is thus formed.

Q ₃ , Q′ ₃ , Q″ ₃ are control transistors, R ₈ ,
R′ ₈ , R _{″ 8} and R ₉ , R′ ₉ , R″ 9 and R ₁₀ , R′ ₁₀ , R″ ₁₀
is a resistor, Q ₄ , Q′ ₄ , Q″ ₄ are transistors, ZD,
ZD′, ZD″ are Zener diodes, which form the error voltage detection circuits DV ₀ , DV ₀₁ , DV ₀₂ , and these form the series dropper type DC stabilizing circuits b, b ₁ , b Then, the power supply sections A, A ₁ and _{A 2 are} formed, and the operation described above using FIG. 2 is performed.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional device, FIG. 2 is a circuit diagram of the principle of the present invention, and FIG. 3 is a circuit diagram of an embodiment of the present invention. A...Main power supply section, _B1 , _B2 ...Sub-power supply section, a...Linking chain converter type DC stabilization power supply circuit, b, _b1 , _b2 ...Series dropper type DC stabilization circuit, I _ov ...Inverter Circuit, Q ₁ ... transistor, R ₁ , R ₂ , R ₃ ... low resistance, D ₁ , D ₂ ... diode,
C ₁ ...Capacitor, CP...Control signal generation circuit, Q ₂ ...
Transistor, C ₂ ... Capacitor, R ₄ ... Resistor, D ₃
…diode, PC, PC′, PC″…hot cutter,
PD, PD′, PD″…Photodiode, PT, PT′,
PT″…Phototransistor, T…Output transformer,
RF, RF ₁ , RF ₂ ... Rectifier filter circuit, D ₄ , D′ ₄ ,
D″ ₄ …Diode, _C3 , _C′3 , C″ ₃ …Capacitor,
DV _s , DV _s1 , DV _s2 ...error voltage detection circuit, SR,
SR′, SR″…shunt regulator, R ₅ , R′ ₅ ,
R″ ₅ , R ₆ , R′ ₆ , R″ ₆ , R ₇ , R′ ₇ , R″ ₇ …Resistance,
DV ₀ , DV ₁ , DV ₂ ...Error voltage detection circuit, Q ₃ , Q′ ₃ ,
Q″ ₃ …transistor, R ₈ , R′ ₈ , R″ ₈ , R ₉ , R′ ₉ ,
R″ ₉ , _R10 , _R′10 , R″ ₁₀ …Resistor, _Q4 , _Q′4 , Q″ ₄ …Transistor, ZD, ZD′, ZD″…Zena diode.

Claims (1)

[Claims for Utility Model Registration] An inverter, a rectifying and smoothing circuit for its output, and an error voltage of the output voltage of the rectifying and smoothing circuit are detected, and the inverter is thereby controlled to keep the output voltage of the rectifying and smoothing circuit constant. a main power supply section consisting of an error voltage detection circuit, a series dropper type DC stabilization circuit for stabilizing the output voltage, one or more rectification and smoothing circuits for rectifying and smoothing the output of the inverter, and each output voltage In a linking chain inverter type multi-output DC stabilizing power supply device comprising one or more sub-power supply units comprising a series dropper type DC stabilization circuit for stabilization, the one or more sub-power supply units include: An error voltage detection circuit is provided on the output side of each rectifying and smoothing circuit, and a circuit for calculating the logical product of each error voltage detection circuit output and the error voltage detection circuit output of the main power supply section is provided, and the inverter is connected to the logical product. A linking chain yoke converter type multi-output DC stabilized power supply device characterized in that it is formed so as to be controlled by a circuit output.