CN2410817Y - 1/n step-down rectifier power source - Google Patents

Abstract

The utility model relates to an AC power input which is transformed into a DC power output, particularly a voltage reducing rectifying power supply. The utility model is provided with a bridge type rectifying circuit, a positive and a negative half cycle charging and discharging circuits, a switching circuit and an identify circuit. Negative electrodes of a positive and a negative half cycle charging rectifying diodes are respectively connected with positive electrodes of the charging and discharging circuit and one end of the switching circuit, the other end of the switching circuit is connected with a load externally, the power supply input end of the identify circuit is connected with a power supply externally, and control output ends are respectively connected with control ends of the switching circuit. The charging and discharging circuits are composed of n capacitors with same polarities connected in series, charging diodes are connected in series between the capacitors, and the capacitors and a charging diode loop are connected with a discharging diode in parallel. The utility model needs no transformer and the utility model has the advantages of large current and small size.

Description

The 1/n decompression rectification power

The utility model relates to a kind of AC power input and is transformed to direct current power output, the especially power supply of step-down rectifier.

Usually decompression rectification power can adopt transformer step-down, capacitance decompression, resistance step-down etc.The transformer step-down must be selected suitable transformer for use, and when especially requiring big electric current, transformer very benzene is heavy; The deficiency of capacitance decompression is to be difficult to accomplish big electric current; Resistance step-down then power consumption is very big.

The purpose of this utility model is to provide the 1/n decompression rectification power of little, the big electric current of a kind of volume, light weight.

The utility model is provided with bridge rectifier, positive-negative half-cycle charge-discharge circuit, the single-phase actuating switch circuit of positive-negative half-cycle, positive-negative half-cycle identification circuit, the negative pole of the positive half cycle charging rectifier diode of bridge rectifier connects the positive pole of positive half cycle charge-discharge circuit and an end of the positive single-phase actuating switch circuit of half cycle respectively, and the negative pole of the negative half period charging rectifier diode of bridge rectifier connects the positive pole of negative half period charge-discharge circuit and an end of the single-phase actuating switch circuit of negative half period respectively.The other end external load of the single-phase actuating switch circuit of positive and negative half cycle.The power input external AC power supply of positive and negative half cycle identification circuit, the control output end connects the control end of the single-phase actuating switch circuit of positive and negative half cycle respectively.Said positive and negative half cycle charge-discharge circuit is made up of the capacitances in series of n same polarity, serial connection charge diode between electric capacity, the positive pole of charging diode connects the negative pole of electric capacity, the negative pole of charging diode connects the positive pole of electric capacity, and each discharge diode in parallel between the capacitance cathode of the negative pole of charging diode and positive and negative half cycle charge-discharge circuit, the positive pole of discharge diode connects the negative pole of charging diode, and the negative pole of discharge diode connects the positive pole of charge and discharge capacitance.Also each discharge diode in parallel between the electric capacity negative pole of the positive pole of charging diode and positive and negative half cycle charge-discharge circuit, the positive pole of discharge diode connects the negative pole of charge and discharge capacitance, and the negative pole of discharge diode connects the positive pole of charging diode.

The output circuit of positive and negative half cycle identification circuit can be finished by same optical coupler with the control end circuit of the single-phase actuating switch circuit of positive and negative half cycle.

The utility model gets up n capacity capacitances in series identical, withstand voltage beyond supply voltage 1/n, when receiving on the power supply that voltage peak is E, obtains the voltage of E/n on each electric capacity.If these series capacitances are disconnected from power supply, the voltage that is keeping E/n on every electric capacity, at this moment, as long as these electric capacity are switched to state in parallel by polarity, and to load discharge, so, the 1/n (being E/n) that will to obtain a voltage be the original edge voltage peak E and output current is the n power supply doubly of input current.The switching of capacitor charge and discharge circuit can realize by the control of positive-negative half-cycle identification circuit to the single-phase actuating switch circuit of positive-negative half-cycle.When the single-phase actuating switch of positive-negative half-cycle switches enough soon, and charge and discharge capacitance can obtain direct voltage through after the Filtering Processing when enough big again.Do not need transformer, electric current is big, volume is little.

Fig. 1 is that circuit of the present utility model is formed block diagram.

Fig. 2 is the circuit theory diagrams of the utility model n=2.

Positive half cycle charge-discharge circuit schematic diagram when Fig. 3 is n=3.

Following examples will be further described circuit composition of the present utility model, operation principle and advantage in conjunction with the accompanying drawings.

As Fig. 1, shown in 2, this power supply is provided with bridge rectifier 1, positive and negative half cycle charge-discharge circuit 2,3, and the single-phase actuating switch circuit 4,5 of positive and negative half cycle, positive and negative half cycle identification circuit 6,7 and switch, power connection and housing, circuit is installed on the printed panel.The power input of the input of bridge rectifier 1 and positive-negative half-cycle identification circuit 2,3 is through K switch external AC power supply～220V, the positive-negative half-cycle charging rectifier diode D of bridge rectifier 1 ₁, D ₃Negative terminal connect the positive pole of positive-negative half-cycle charge-discharge circuit 2,3 and an end of the single-phase actuating switch circuit 4,5 of positive-negative half-cycle respectively.The other end external load of the single-phase actuating switch circuit 4,5 of positive-negative half-cycle, the control end of the single-phase actuating switch circuit 4,5 of positive-negative half-cycle is connected to the control output end of positive-negative half-cycle identification circuit 6,7 respectively.With n=2 is example, rectifier diode D ₁～D ₄Form bridge rectifier, positive and negative half cycle charge-discharge circuit is respectively by the capacitor C of 2 same polarities ₁, C ₂And C ₃, C ₄Be composed in series C ₁With C ₂And C ₃With C ₄Between serial connection charge diode D respectively ₅And D ₈, diode D ₅And D ₈Positive pole connect capacitor C respectively ₁And C ₃Negative pole, negative pole then connects capacitor C respectively ₂And C ₄Positive pole.And charging diode D ₅And D ₈Negative pole respectively with capacitor C ₁And C ₃Positive pole between parallel discharge diode D respectively ₇And D ₁₀, D ₇And D ₁₀Positive pole meet charging diode D ₅And D ₈Negative pole, D ₇And D ₁₀Negative pole meet charging capacitor C ₁And C ₃Positive pole.D ₅And D ₈Positive pole respectively with C ₂And C ₄Negative pole between also parallel discharge diode D respectively ₆And D ₉Field effect transistor G ₁, G ₂Respectively with voltage stabilizing didoe D ₈, D ₁₉, triode G ₃, G ₄, optical coupler A, B form the single-phase actuating switch circuit of positive and negative half cycle, G ₁, G ₂Grid voltage by diode D ₁₃～D ₁₇, capacitor C ₅, resistance R ₁And R ₂Provide Deng the grid voltage supply circuit of forming.Optical coupler A, B and diode D ₁₁, D ₁₂Deng the positive and negative half cycle identification circuit of composition.

When mains switch K connected, the positive half cycle of electric current made the conducting of positive half cycle identification circuit, and the single-phase actuating switch of positive half cycle is turn-offed, and passed through D simultaneously ₁, D ₅, D ₄To C ₁, C ₂Charging reaches peak value 310V.In like manner, when power supply is in negative half period, the positive single-phase actuating switch conducting of half cycle, the single-phase actuating switch of negative half period turn-offs C ₁, C ₂Discharge, to the voltage of the about 155V of load output, electric current passes through D simultaneously ₂, D ₈, D ₃To C ₃, C ₄Charging goes round and begins again, and reaches the purpose of AC-DC conversion and step-down.In like manner can make 1/3,1/4 ... the step-down high-current dc power supply of 1/n.Charge and discharge capacitance in the wherein positive and negative half cycle charge-discharge circuit respectively be n only, charging diode respectively be (n-1) only, discharge diode respectively is 2 (n-1).In Fig. 2, triode G ₃, G ₄The signal of telecommunication to optical coupler A, B amplifies respectively.

The schematic diagram of the positive half cycle charge-discharge circuit when Fig. 3 provides n=3.

Claims (2)

1.1/n decompression rectification power, be provided with bridge rectifier, the negative pole that it is characterized in that the positive half cycle charging rectifier diode of bridge rectifier connects the positive pole of positive half cycle charge-discharge circuit and an end of the positive single-phase actuating switch circuit of half cycle respectively, the negative pole of the negative half period charging rectifier diode of bridge rectifier connects the positive pole of negative half period charge-discharge circuit and an end of the single-phase actuating switch circuit of negative half period respectively, just, the other end external load of the single-phase actuating switch circuit of negative half period, just, the control end of the single-phase actuating switch circuit of negative half period is just connecing respectively, the control output end of negative half period identification circuit, just, the power input external AC power supply of negative half period identification circuit; Just said, the negative half period charge-discharge circuit is made up of the capacitances in series of n same polarity, serial connection charge diode between electric capacity, the positive pole of charging diode connects the negative pole of electric capacity, the negative pole of charging diode connects the positive pole of electric capacity, the negative pole of charging diode with just, each discharge diode in parallel between the capacitance cathode of negative half period charge-discharge circuit, the positive pole of discharge diode connects the negative pole of charging diode, and the negative pole of discharge diode connects the positive pole of charge and discharge capacitance, the positive pole of charging diode with just, also each discharge diode in parallel between the electric capacity negative pole of negative half period charge-discharge circuit, the positive pole of discharge diode connects the negative pole of charge and discharge capacitance, and the negative pole of discharge diode connects the positive pole of charging diode; Charge and discharge capacitance in the said positive and negative half cycle charge-discharge circuit respectively be n only, charging diode respectively be (n-1) only, discharge diode respectively is 2 (n-1).

2. 1/n decompression rectification power as claimed in claim 1 is characterized in that the control output end of said positive and negative half cycle identification circuit and the control input end of the single-phase actuating switch circuit of positive and negative half cycle be made up of optical coupler.

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