SU748666A1 - Method of short-duration redundancy of electric mains power supply and device for effecting same - Google Patents

Description

ryf alWeHTatTScH reservable expressions. Due to these properties, they are not used for short-term power reserving of low power consumers.

. Closest to the proposed method is a short-term backup power supply, in which a pre-charged capacitive storage device is used as a backup source. The method consists in choosing the storage capacitor or its charging voltage based on the load parameters and the expected duration of the power supply interruption, controlling the power supply of the main source and measuring the voltage on the load. When the power supply is interrupted and the voltage is reduced at the load to the minimum permissible value, the filter capacitance is separated from the load and a reserve source is connected to it, which is discharged at a constant speed. They monitor the voltage of the backup source and, when the voltage drops to the minimum permissible value, produce additional voltage, for which the storage capacity is divided; two equal parts, including them in series and at the same speed, are discharged to the load.

The device in which this method is carried out contains a backup power supply, a capacitive drive, the output of which through a switch and voltage regulator is connected to the load, an input voltage control relay, ocHOBHof: a power supply, a rectifier with a capacitive filter at the output, separated from the load a diode, and a charge device (auxiliary to the driver). The capacitive switch consists of a voltage control relay and a capacitor bank divided into two parts, which are switched in parallel and in series with the help of the input voltage control relay and the voltage control relay. Rectifier consists of a transformer and a power rectifier 2

However, the aforementioned short-time power backup method does not provide the required energy for the drive needed to compensate for voltage dips during the power source caused by current surges from one of the consumers of the rectifier. This deficiency is due to the fact that the technically feasible adjustable elements of continuous voltage regulators have low load capacity and large resistance to pressure. .

The purpose of a performance test is to increase the reliability of Löktröpani by increasing the speed of Recoil of energy by a capacitive drive. ,

748666

This goal is achieved by the fact that in the method of short-term backup of electrical power supply of the network, in which a pre-charged capacitive storage device is used as a backup source, and the main power source is connected to the load through a filter containing a capacity, which means that the storage capacity is OR voltage

its charge, based on the parameters of the load and the expected power supply interruption, measure the voltage at the load and, when the voltage drops to its minimum permissible value, connect a capacitive storage device, the size of the charged capacitance of the filter is chosen based on the storage capacitance is directly proportional to the magnitude of the difference in the charge voltage of the accumulator and the maximum achievable voltage on the load and inversely proportional to the difference between the maximum and minimum voltage on the load, when connected from The capacitive storage device charges the filter capacitance and simultaneously discharges it to the load.

A device for carrying out the method comprising a charging device connected to a load unit

Voltage monitoring, main power supply with a capacitive filter at the output, the capacitor battery of which is separated from the load by a diode, and. backup power source — made in the form of a capacitive storage device and output through a switch connected to the load, the charging device is equipped with a voltage regulator, and the capacitive filter is supplemented with a second capacitor battery connected

0 with the load, the value of the capacity of the second capacitor battery is selected by the formula:

g e - g

(one)

Ti Y1

H

mch.

where Sf - the capacity of the second capacitor battery; C, is the storage capacity; Е - tension of charge accumulator; and ncuKc is the maximum allowable load on the load; Jwmh. minimum allowable voltage at the load; CH - load capacity. In addition, the switch in the device is made on the thyristor.

Shortcuts My network backup is powered up in the following way.

For example, they are given by the value of the storage voltage of the storage device, then by the expected yyutelnosti Interruption of the power supply t, by the parameters of the load (average power in the load in the period

the reserves Pft and the voltages U c., determine the storage capacity by the formula: (E, msx mim / Determine by the formula (1) the magnitude of the charging capacity of the filter. The storage capacitor charges and the voltage measured at the load. With a decrease in the voltage on the load to the minimum permissible value, the accumulator is connected to the charged capacitance of the filter and the load, while all the excess energy of the backup source (minus the energy loss during dosage independent of the discharge circuit impedance) time determined by the constant time of the charging circuit Yes, the capacitance of the filter is applied to the load. Thus, the increased storage voltage by means of the charging capacity of the filter is converted into a permissible value of the storage voltage of the storage device and filter connected to the load and discharged to the minimum permissible voltage value. If necessary, make an additional charge of the accumulator by dividing its capacity into two equal parts, turning on the sequentially indicated parts of the accumulator, discharging them to the load and charging capacity of the filter, which in this case lzhna satisfy the expression :. 1/2 and them - Tsmachg t g Noals It is possible to have another sequence of selection of storage parameters when the known capacity of the charged filter determines either the capacitance on the accumulator or the voltage of its charging. The drawing also shows the functional diagram of the device for The proposed short-term power backup method. The device contains a main power source 1, a capacitive filter 2, a voltage control unit 3, a load 4, a capacitive drive 5, a switch b, a discharge resistor 7, a capacitor battery 8, a second capacitor battery 9, a thyristor 10, a diode 11, a charger 12. A capacitive filter 2, a voltage control unit 3 and a load 4 are connected to the output of the main power source 1. The output of the capacitive storage device 5 through the actuator circuit of the switch 6 and the discharge resistor 7 is connected to the capacitive filter 2. The control circuit of the switch 6 is connected to swing unit 3 control voltage. The capacitive filter 2 consists of a capacitor battery 8 connected to the output of the main power source 1, a second capacitor battery 9 selected according to the formula 1 and connected to block 3 with voltage control 4 to the load 4 and the actuator circuit of switch 6 executed on the thyristor 10. The capacitor battery 8 is separated from the second capacitor battery 9 by a diode 11 connected in the conducting direction. Charger 12 is equipped with a voltage regulator and connected to the input of the capacitive storage node 5. When the power supply of the main power source 1 is lost or short-term current ramps in the load 4, the voltage on the capacitive filter 2 begins to decrease. Upon reaching the minimum load voltage 4, the voltage control unit 3 turns on the switch 6. As a result, the capacitive drive 5 through the discharge resistor 7 is discharged to the second capacitor battery 9 and load-4. At the first transient stage of discharge, the voltage on load 4 increases from the minimum allowable to the maximum allowable value if the voltage drop was caused by a power outage of the main power source 1. If the initial decrease in voltage was caused by a surge of current into the load 4, then a decrease in the output of the main power supply 1 due to the connection of a charged capacitive voltage 5 begins to play its role. So the voltage on the load 4 or remains the minimum allowable level, if the rate of overcurrent and. The discharge in load 4 is equal, or it begins to increase if the discharge current rate in load 4 exceeds: the current accumulation rate. The discharge current rate can be changed by selecting the value of the resistance of the discharge resistor 7 .. In the second stage of the discharge of the capacitive storage device 5, the voltage on the load 4 drops from the maximum value to the minimum acceptable value. The second stage of the discharge determines in essence the duration of the backup and is characterized by the discharge of the capacitive storage 5 and the second capacitor battery 9 to the load 4. If the capacity of the second capacitor battery 9 exceeds the capacity determined by expression (1), for example, to simplify the device the diode 11, and the batteries 8 and 9 turn on the battery, the voltage on the load 4 in the first stage of the discharge will not reach the maximum value and the energy loss increases when charging the capacitive filter 2. As a result, the duration of the second nd stage discharge dropped.

The switch b can be executed, for example, on the thyristor 10. If the current through the thyristor 10 reaches the value of its shutdown current when the capacitive accumulator 5 is discharged, the switch b disconnects the capacitive accumulator 5. In this case, the current in the load 4 is maintained by the charge The second capacitor bank 9 is used. When the capacitor has a permissible voltage value of 4, the control unit on voltage 3 re-turns on the thyristor 10 and the charge-discharge cycle of the backup process repeats. again. At the same time, the amplitude of the voltage pulse at load 4 and the duration of each cycle are reduced from cycle to cycle if the capacitive storage 5 is not recharged (or charged by a small current} during the backup process. In case of a decrease in the average power in the load 4, this property reduces depth of capacitive storage 5.

Dispensing capacity may be included in single-link and dual-link LC and R / C smoothing power supply filters with short-term redundancy.

The proposed method of short-term power backup allows the discharge of the discharge circuit to elements with 10-100 times greater cyclic load capacity (a switch on the thyristor and a discharge resistor, can be used as wiring), than in the discharge circuit prototype (switch and active transistor of continuous voltage regulator). Due to this, the rate of energy transfer to the load by a capacitive storage device can be increased several times, the need for the use of a voltage regulator in the discharge circuit is no longer necessary.

Claims (3)

1. A method of short-term backup of a power supply network, in which a pre-charged capacitive storage device is used as a backup source, and the basic power source is connected to the load through a filter containing a capacitor. the bone is that the storage capacity of the storage device is selected or the charge voltage is derived from. load parameters and the expected duration of the interruption of the power supply, measure the voltage on the load and, while reducing the voltage on it to the minimum permissible value, connect a capacitive drive, characterized in that, in order to increase the reliability of the power supply by increasing the rate of energy output by the capacitive drive, the amount charged the filter capacitance is selected, proceeding from the storage capacitor, is directly proportional to the value of the difference in the storage voltage of the storage drive and the maximum allowable voltage at the load inversely proportional to the difference of maximum and minimum voltages at the load, when connected by the capacitive storage means is charged filter capacitance and simultaneously zhayut discharge its load. 2. A device for carrying out the method according to claim 1, comprising a charging device, a voltage monitoring unit connected to the load, a main power source with a capacitive filter at the output, a capacitor battery which is separated from the diode load, and a backup power source made in the form of a capacitive a storage device and an output through a switch connected to a load, characterized in that the charging device is equipped with a voltage regulator, and a capacitive filter; supplemented by a second capacitor battery connected to the load, while the capacity value of the second capacitor battery is selected by the formula E - and Mox. C (V H MaxT Mni-, where Cjy is the capacitance of the second capacitor bank; С - storage capacity; E - charge accumulator voltage,. wCTKc is the maximum allowable voltage at the load; and min. minimum allowable voltage at the load; C - load capacity. 3 .. The device according to claim 1, characterized in that the switch is made on a thyristor. Sources of information taken into account in the examination 1. Katayev V.E. and others. Power supply of communication devices. Ed. Kitaeva. Textbook for universities. M., Svy, 1975, p. 279-280, fig. 13.4 and 13.5. 2. USSR author's certificate number 513358, cl. G 05 F .1 / 62, 19J3 (prototype).