HU201629B - Circuit arrangement for feeding by means of controlled power transfer, particularly for eliminating switching transients - Google Patents

Abstract

The invention relates to a circuit arrangement for electrically controlled supply of energy, in particular for the elimination of circuit transients, in which an AC voltage source (Uo) is connected to the power consumer (Sa). The essence of the invention is that between the AC voltage source * and the power consumer (Sa) a switching circuit (VK) and an observation circuit (Fl) are connected, while another input of the same switching circuit (VK) by a control circuit (V) at another Output of the observation circuit (Fl) is connected. Furthermore, between the switching circuit (VK) and the power consumer, a converter, for. As a transformer to be switched. Fig. 1 {circuit arrangement; electrically controlled power transmission; Schaltungstransienten; AC voltage source; Electricity consumers; Switching circuit; Monitoring circuit; converter; Transformer}

Description

BACKGROUND OF THE INVENTION The present invention relates to a circuit arrangement for controlled power supply electrical power, in particular to eliminate switching transients.

An important part of our network-less electronic devices is the power supply. Its function is multiple protection of the contacts (galvanic isolation from the mains), generation of various power voltages required by the circuits, and compensation of the voltage fluctuations of the network - stabilization, short-circuit protection, etc.

Providing the stabilization function is a major concern even with medium power consumption of 50-200 W. Voltage fluctuations in the network may exceed ilOX in special cases, -15, + 10X is also required. In our conventional power supply units (mains transformer - rectifier - pins capacitor - stabilizer circuit), the voltage of the filter capacitor must be slightly higher than the output voltage even at the minimum of the mains voltage. This causes an almost unbearable dissipation of the permeable element of the stabilizer at rated mains voltage, but especially at maximum mains voltage. To make matters worse, most devices are confined to low-voltage circuits (5V digital circuits). As a result of the set, the resulting efficiency of 30-40X is already good. The devices are big, heavy and too hot.

With the spread of computers, switching power supplies have come to the forefront. After rectifying the mains voltage, they perform power transmission and voltage conversion at medium frequency interruption. These power supplies are small in size, light in weight, and highly efficient. However, their huge problem is the significant and difficult to reduce interference they cause, and the need for a high quality modern component fleet, which is more expensive and has a very high number of circuit components whose potential failures reduce reliability.

Attempts have been made to improve the efficiency of analog power supplies by using pre-regulation. Because of the relatively high current levels, switching devices can use thyristors - but these can only be switched on electronically, not off. thus, control is only possible in the downstream line voltage. This requires a so-called pre-regulator control circuit - ultimately, its construction is complicated and uncertain.

Another problem is the selection of filter capacitors. In filtering circuits that provide good filtration, the required high-capacity capacitor, when energized when connected to the mains, generates a huge current surge, which can break rectifiers, melt fuses, and at high rated voltages, the filter capacitors also have high peak voltages.

Circuits that do not fully allow the mains voltage to fluctuate under load are also used because the device uses pre-stabilization.

Pre-stabilization involves using rectifiers between the transformer and the stabilizer inputs to limit the voltage difference between the stabilizer inputs and outputs as the load and mains voltage changes. Thus, dissipation on the stabilizer can be minimized.

Reference is also made in the literature to primary side regulation, which, however, does not have the advantages of the present invention.

A controlled switch is used in U.S.P.

524,413, which is a controlled switch, but is only of secondary circuit design.

Closest experimental embodiments of the present invention may provide a circuit that intervenes directly to resolve the problem using network terminals. In this solution, too, they are experimenting with the elements used so far (thyristor, triac), which cannot be controlled due to the known problem.

There are several circuit layouts in Péter Loska's. Power Control with Ignition Angle Control. The common feature of these circuits is that they provide power control (using thyristors, triacs), control mode is direct control, phase angle control based on the voltage of the network.

The invention differs essentially from the known solutions in that the voltage source and the consumer are interfered with in such a way that the flow of energy can be kept within predetermined or customer defined limits.

This is why the switching can be called a controlled · power supply.

The circuit arrangement according to the invention has led to the realization that not only one of the essential parameters of the power transmission line, the voltage, but also the current (which is the load current of the consumer) must be monitored, preferably simultaneously and continuously. In the event that any of the monitored parameters exceeds a value requested or pre-set by the consumer, a switch controlled by a suitably configured control circuit will necessarily interrupt or activate the circuit within a period of time.

Accordingly, the invention relates to a circuit arrangement for a controlled power transmission electric power supply, in particular to eliminate switch-on transients, where there is a periodically changing voltage source connected to their consumers.

In accordance with the present invention, a first input of a switching circuit is connected between a periodically varying voltage source and a consumer via a monitoring circuit, the other input of the switching circuit being connected to a further output of the monitoring circuit via a control circuit. The monitoring circuit monitors the input voltage and the consumer load current simultaneously.

An embodiment of the invention wherein an additional converter is inserted between the switching circuit and the consumer is preferred.

A preferred embodiment of the circuit arrangement according to the invention which interrupts the power supply when a periodically variable voltage source connected to the consumer exceeds a certain value is configured so that the control circuit is connected to the consumer via an additional monitoring circuit.

In a preferred embodiment of the invention, the converter is a transformer having a primary winding connected in series at the switching clock and the converter is a transformer having a primary winding consisting of two parts and a switching circuit formed by a switching circuit controlled by a semiconductor switch. having a control electrode connected to the output of the control circuit.

Preferably, the switching circuit is formed from a controlled semiconductor switch having a control electrode connected to the output of the control circuit, and the second monitoring circuit is configured to measure a parameter of the consumer and comprises a fault detector and a non-contacting coupling the output of the coupler is the output of the monitoring circuit.

Several parameters can be monitored and controlled simultaneously in a given device. For example, in the case of a power supply, monitoring the current flowing through the output transistor, the voltage across it, and the output short circuit in the secondary circuit.

The circuit arrangement of the present invention will now be described in more detail by way of exemplary embodiments, in the accompanying drawings.

1-4. Figures 1 to 5 are block diagrams of an exemplary embodiment of a circuit arrangement according to the invention;

5-7. Figures 4 to 5 show an exemplary embodiment of the converter, while Figs

Figure 8 shows a more detailed exemplary embodiment of the circuit arrangement of the present invention.

FIG. via the on / off switching circuit, the consumer Sa is connected such that the monitoring circuit which simultaneously monitors the input voltage and the load current of the consumer is provided with an additional output which is via the control circuit V for switching on and off within a period of time Vk. connected to another input.

In the embodiment shown in FIG. 2, a converter A, preferably a transformer A, is connected between the on / off switch circuit within the period Vk and the consumer Sa, and in the embodiment shown in FIG. 3, an additional monitoring circuit F2 is also connected. the output of which is connected to a further input of the control circuit V.

In the embodiment shown in Fig. 4, all of the aforementioned units are included, i.e. F1 monitors the input voltage and the consumer load current simultaneously, and F2 further monitors the converter A and V control circuits and the on / off switching circuit Vk.

5-7. FIGS. 1A and 4B illustrate an embodiment of a converter A and a switching circuit for switching on and off within a period of time Vk, wherein the transformer A has a primary winding having a switching circuit for switching on and off within a period of time Vk, e.g. on.

In the embodiment shown in Fig. 5, the primary winding of the transformer Tr is also divided and interposed in series with an on / off switching circuit within a period of time Vk.

Fig. 8 shows a more detailed embodiment of the circuit arrangement according to the invention, wherein the voltage source U0 is a periodically changing signal source having three serial circuits consisting of two diodes D1-D2, D3-D4, D5-D6. A voltage resistor RA and RB are also connected in series to the voltage source Uo, which together with the diodes D1-D6 and resistors R1 and R2 connected to the common point of the diodes D5 and D6 form a monitoring circuit for simultaneously monitoring the input voltage and the load current.

The control circuit V consists of a comparator K1 and K2, which on the one hand monitors the monitoring circuit for the simultaneous monitoring of the input voltage and the consumer load current, and on the other hand, during the period Vk.

EN 201629 is connected to a switching circuit that provides power. One input of comparator K2 is connected to the common anode point of the diodes D1-D2 before the RA resistor and the other input to the common anode point of the diodes D3 to D4 after the resistor RA. The output of the comparator K2 is connected to one of the reference inputs Kf of the comparator K1, while the common cathode point of the diodes 05-D6 is connected to the other measuring signal input of the same comparator KI via a voltage divider consisting of resistors R1 and R2. The output of the second monitoring circuit F2, optionally modifying the intervention, is also connected to the reference input Kf of the comparator KI so that the two signals are virtually superimposed and the output of the comparator KI to the switching circuit for providing an on / off switch within the time slot Vk. connected to its electrode, which is serially inserted between the two-part primary windings of the transformer Tr. As an example! In the embodiment, the converter A further comprises a rectifier G. In this embodiment, the consumer Sa is supplied with direct current and the rectifier G is connected to the consumer Sa through a stabilizer St. Thus, the additional monitoring circuit F2 in this case monitors the voltage across the stabilizer St, but would also detect the temperature or current of the transistor through the stabilizer St, for example.

The input and output of the stabilizer St is connected via an error detector HK to an optocoupler O, the output of which is connected to the reference input Kf of the comparator KI.

Thus, in the circuit layout shown in the figure, comparator K1 compares the instantaneous value of the voltage source U0 with a predetermined value corrected by an error signal.

If the instantaneous value is greater, the comparator OFF will overturn and the on / off switching circuit within Vk will interrupt the serial connection between the primary winding parts of the transformer Tr.

Comparator K2 compares the current flowing through the primary winding of the transformer Tr with a preset value, and when the measured value exceeds a preset value, comparator K2 overturns, which overturns the comparator KI and interrupts the primary windings of the transformer Tr as described above. serial connection.

The current is monitored by RA and RB resistors and the D1-D4 diodes provide the voltage polarity to be selected.

Thus, it can be seen that the circuit arrangement of the present invention is simple in design, implemented with a small number of circuits, and has no moving, abrasive component and thus high reliability.

A further advantage of such a power supply arrangement is that the capacity of the filter or smoothing capacitor connected to the middle point of the rectifier G and the stabilizer St, which is not shown in Fig. 8, can be arbitrarily high, thus minimizing the voltage drop on the St stabilizer.

It is also a significant advantage that the Tr transformer transformer is significantly smaller in size and power than the conventional analog system, since the loss of power on the St stabilizer and the fluctuation of the periodically changing voltage source U0 do not reach the Tr transformer. In case of mains voltage this fluctuation can reach 30%.

Claims (8)

PATENT CLAIMS A circuit arrangement for a controlled power transmission electrical power supply, in particular for eliminating switching transients, wherein a periodically variable voltage source (Uo) is connected to the consumer (s), characterized in that the periodically variable voltage source (Uo) and the consumer (Sao) ) is connected via an on / off switch circuit (Vk, the first input of which is connected to an on-off switch circuit (Vk, the second input control circuit) via a monitoring circuit (F1) simultaneously monitoring the input voltage and the consumer load current) V) is connected via an additional output of a monitoring circuit (F1) which simultaneously monitors the input voltage and the load current of the consumer. The switching arrangement according to claim 1, characterized in that an additional converter (A) is connected between the switching circuit (Vk) providing the switch-on and the consumer (Sa) within a period of time. The circuit arrangement according to claim 1 or 2, characterized in that the control circuit (V) is further provided with an additional input which is connected to the consumer (Sa) via an additional monitoring circuit (F2). The switching arrangement according to claim 2, characterized in that the converter (A) is a transformer (Tr) having a primary winding which is connected in series to a switching circuit (Vk) which provides an on / off switch within a period of time. 5. The switching arrangement according to any one of claims 1 to 5, characterized in that the converter (A) is a transformer (Tr) having a primary winding consisting of two parts, in which a switching circuit (Vk) for switching on within a period of time is inserted. The circuit arrangement according to claim 4 or 5, characterized in that a GB 201629 Β an on / off switching circuit (Vk) is formed from a controlled semiconductor switch having a control electrode connected to the output of the control circuit (V). 7. A switching arrangement according to any one of claims 1 to 6, characterized in that the further monitoring circuit (F2) is configured to measure a parameter of the consumer and consists of a faultless indicator (HK) and a movable non-contacting coupling element, such as an optocoupler output of additional monitoring circuit (F2). 8. A circuit arrangement according to any one of claims 1 to 4, characterized in that the converter (A) is a transformer (Tr) having a secondary controller (G) connected to its secondary winding, an output of which is connected to an additional stabilizer (St) and a further monitoring circuit (F2). It is designed for sensing the voltage between the inlet and the outlet of the stabilizer.