High-voltage capacitor electricity-taking alternating current power supply

Abstract

The invention discloses a high-voltage capacitor electricity-taking alternating current power supply, which comprises an electricity-taking circuit connected with an external high-voltage line so as to receive electric energy of the high-voltage line and output the electric energy after the electric energy is subjected to isolation and voltage reduction through a transformer; the output end is connected with the output side of the power taking circuit and outputs alternating current to an external output load; the rectifying circuit is composed of an alternating current filter capacitor C2, a rectifying diode Z and a capacitor C1; the rectifier diode Z is connected with the output end of the power taking circuit, and the capacitor C1 is connected to the output end of the rectifier diode Z to convert alternating voltage into direct voltage; the voltage stabilizing circuit is connected with the rectifying circuit, and a consumption load is arranged in the voltage stabilizing circuit; therefore, the stability of the output voltage of the output end is controlled. According to the high-voltage capacitor electricity-taking alternating-current power supply, the mode that alternating current is reversely controlled through direct current is adopted, alternating-current sine-wave electricity stable-voltage output is achieved, the circuit complexity is greatly reduced, and the circuit conversion efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to a high-voltage AC power supply, more specifically to a high-voltage capacitor power supply, and even more specifically to a high-voltage capacitor power-stabilized power supply with a sinusoidal wave output. Background Art

[0002] High-voltage capacitor power supply technology refers to a technology that converts high-voltage electrical energy of high-voltage transmission lines into safe low-voltage electrical energy. It is usually used to supply stable power to low-voltage secondary control electrical equipment of high-voltage lines and equipment. It can ensure the long-term use of load equipment and is suitable as a reliable power supply equipment for online detection, inspection, anti-theft, control and other electrical equipment on high-voltage transmission lines.

[0003] Currently, existing electrical equipment is powered by either a DC power supply or an AC power supply. The existing high-voltage power supply converts the AC power on the high-voltage line into a regulated DC power output. When AC power is needed to be provided to electrical equipment, a DC / AC inverter is added to the regulated DC output to provide a regulated AC power supply. In the above method, on the one hand, in order to reduce the complexity of the circuit, the final output AC power is a triangular wave or a square wave, and the voltage and current harmonics are relatively large. On the other hand, the power supply undergoes multiple conversions, which will lead to serious internal power loss and low efficiency. Summary of the invention

[0004] In view of the shortcomings of the prior art, the object of the present invention is to provide a high-voltage capacitor AC power supply that can output sinusoidal AC power and has very low loss.

[0005] To achieve the above object, the present invention provides the following technical solution: a high voltage capacitor power supply, comprising: A power-taking circuit is connected to an external high-voltage line to receive electric energy from the high-voltage line, isolate the electric energy, reduce the voltage, and then output it; The rectifier circuit is composed of a rectifier diode Z and capacitors C1 and C2; the rectifier diode Z is connected to the power-taking circuit, the capacitor C2 is connected in parallel with the output end and connected to the input end of the rectifier diode Z, and the capacitor C1 is connected to the output end of the rectifier diode Z to convert the AC voltage output by the power-taking circuit into a DC voltage; AC output interface, connected between the rectifier diode Z and the power taking circuit, used to output AC power to the external output load; The voltage stabilizing circuit is connected to the rectifier circuit. The voltage stabilizing circuit has a consumption load. The current of the output end circuit loop of the rectifier diode Z is controlled by adjusting the current on the internal consumption load, thereby achieving the stability of the AC output voltage of the control output interface.

[0006] As a further improvement of the present invention, when the output load becomes lighter, that is, the output current becomes smaller and the output voltage becomes higher, the voltage stabilizing circuit reduces the output voltage of the AC output interface by increasing the current flowing through the internal consumption load; when the output load becomes heavier, the voltage stabilizing circuit increases the output voltage of the AC output interface by reducing the current on the internal consumption load; Or when the input voltage becomes higher, that is, the output voltage becomes higher, the output voltage of the AC output interface is reduced by increasing the current flowing through the internal consumption load; when the input voltage becomes lower, the AC output voltage of the output interface is increased by reducing the current on the internal consumption load.

[0007] As a further improvement of the present invention, the voltage stabilizing circuit comprises: A consumption resistor R1, the consumption resistor R1 is a consumption load, and one end of the consumption resistor R1 is connected to an output end of the rectifier diode Z; The modulation tube Q has a first end connected to the end of the consumption resistor R1, and a second end connected to the other output end of the rectifier diode Z, and forms a current loop with the consumption resistor R1; the control end receives a signal to adjust the current flowing through the consumption resistor R1, thereby affecting the current and voltage of the AC output end; A control circuit U, which is connected to the control end of the modulation tube Q to send a signal to the control end of the modulation tube Q; Among them, when the output load becomes lighter or the input voltage becomes higher, that is, the output current becomes smaller and the output voltage becomes higher, the control circuit U controls the modulation tube Q to increase the current flowing through the internal consumption resistor R1 to reduce the output voltage of the AC output interface; when the output load becomes heavier or the input voltage becomes lower, the modulation tube Q is used to reduce the current on the internal consumption resistor R1 to increase the output voltage on the AC output interface, thereby stabilizing the AC output voltage of the AC output interface within a certain value.

[0008] As a further improvement of the present invention, the modulator tube Q is a triode, the collector of which is connected to the end of the consumption resistor R1, the emitter is connected to the output end of the rectifier circuit Z, and the base is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the current input into the base.

[0009] As a further improvement of the present invention, the modulator tube Q is a field effect tube, the drain of which is connected to the end of the consumption resistor R1, the source is connected to the output end of the rectifier circuit Z, and the gate is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the duty cycle of the square wave input to the gate.

[0010] As a further improvement of the present invention, the power taking circuit comprises: A step-down capacitor C, one end of which is connected to one end of an external high-voltage line; Transformer T, the input side of the transformer T is connected to the end of the step-down capacitor C, and the other end is connected to the other end of the high-voltage line to form a high-voltage loop to receive the electric energy after the step-down capacitor C, and further step down and isolate the electric energy through the transformer T and output it through the output side of the transformer T.

[0011] As a further improvement of the present invention, the control circuit U is also connected to the AC output interface as a sampling signal of the AC output voltage to form a closed-loop control.

[0012] As a further improvement of the present invention, the voltage stabilizing circuit is further connected with a diode D and a capacitor C3 to form a loop, and the diode D is further connected in parallel with a resistor R2.

[0013] The beneficial effect of the present invention is that through the setting of the power-taking circuit, isolated and safe low-voltage AC power can be effectively obtained from the external high-voltage line, and then the AC output interface can be used to provide AC power to the external device, and through the setting of the voltage stabilizing circuit, the voltage at the input end of the rectifier diode Z can be effectively reversely adjusted by regulating the current of part of the circuit at the output end of the rectifier diode Z. In this way, an AC regulated power supply is provided to the external device in a simple and reliable manner, and the output is an AC sinusoidal AC voltage, without the need for DC / AC conversion, and the loss is very low; when the load is maximum, the current on the consumption resistor is 0A, and the entire circuit basically does not consume additional electrical energy, all of which is used for output, and the post-stage conversion efficiency can reach more than 99%; in addition, through the setting of capacitor C2, the current harmonics of the circuit can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The circuit diagram of the high voltage capacitor of the present invention is to draw power from the AC power supply. DETAILED DESCRIPTION

[0015] The present invention will be further described below in detail with reference to the embodiments shown in the accompanying drawings.

[0016] Reference Figure 1 As shown, a high-voltage capacitor AC power supply of this embodiment is characterized by comprising: The power taking circuit 1 is connected to an external high voltage line to receive the electric energy from the high voltage line, isolate the electric energy, reduce the voltage and then output it; The rectifier circuit is composed of a rectifier diode Z, capacitors C1 and C2; the rectifier diode Z is connected to the power circuit 1, the capacitor C2 is connected between the rectifier diode Z and the power circuit 1, and the capacitor C1 is connected to the output end of the rectifier diode Z to convert the AC voltage output by the power circuit 1 into a DC voltage; The AC output interface 3 is connected between the rectifier diode Z and the power taking circuit 1 and is used to output AC power to an external output load; The voltage stabilizing circuit 2 is connected to the rectifier circuit. The voltage stabilizing circuit 2 has a consumption load. The current of the output end circuit loop of the rectifier diode Z is controlled by adjusting the current of the internal consumption load; thereby achieving the stability of the output voltage of the AC output interface 3. In the process of using the power supply of this embodiment, the electric energy of the high-voltage line can be output after isolation and voltage reduction through the transformer through the action of the power taking circuit 1. Then, through the action of the rectifier circuit and the voltage stabilizing circuit 2, the current size in the overall power supply is regulated, and then the output voltage is regulated. Finally, the output end interface 3 is used to achieve the regulated output of AC power. Since the output end interface 3 is connected to the output end of the transformer, the AC power output by the AC output interface 3 is a sine wave. Compared with the DC / AC inversion method used in the prior art, the number of conversions is small, and the corresponding conversion efficiency is higher. Moreover, through the setting of capacitor C2, the current harmonics of the overall circuit can be reduced.

[0017] As a specific implementation of the improvement, when the output load becomes lighter, that is, the output current becomes smaller and the output voltage becomes higher, the voltage stabilizing circuit 2 reduces the output voltage of the AC output interface 3 by increasing the current flowing through the internal consumption load; when the output load becomes heavier, the output voltage of the AC output interface 3 is increased by reducing the current on the internal consumption load. In the process of voltage stabilization control by the voltage stabilizing circuit 2, compared with the method in the prior art, under high load conditions, when the power supply outputs at high load, the internal consumption load does not consume energy, and all energy is used for output; therefore, the loss is very low at full power output, and thus very little heat is generated. At the same time, since the detection equipment on the actual high-voltage line basically does not have a no-load operation condition, the power supply of this embodiment has basically no loss caused by no-load conditions. In this way, compared with the existing method, the overall lower loss effect can be effectively achieved. At the same time, because the overall current in the circuit remains unchanged, only the current distribution is different. Therefore, the current on the primary side remains basically unchanged, so that the circuit is basically not affected by changes in the output load, reducing the sudden change and harmonic component of the primary high-voltage side current, reducing interference with power supply equipment during collection, and increasing detection accuracy and reliability. Similarly, when the input voltage (that is, the input voltage of the external high-voltage line) becomes higher, the voltage applied to the load is stabilized by increasing internal consumption. When the input voltage becomes lower, the voltage applied to the output load is stabilized by reducing internal consumption, thereby achieving output AC voltage stabilization when the input voltage changes.

[0018] As an improved specific implementation, the voltage stabilizing circuit 2 includes: A consumption resistor R1, the consumption resistor R1 is a consumption load, and one end of the consumption resistor R1 is connected to the output end of the rectifier diode Z; The modulation tube Q has a first end connected to the end of the consumption resistor R1, and a second end connected to the other output end of the rectifier diode Z, and forms a current loop with the consumption resistor R1; the control end receives a signal to adjust the current flowing between the consumption resistor R1 and the output end; A control circuit U, which is connected to the control end of the modulation tube Q to send a signal to the control end of the modulation tube Q; Among them, when the output load becomes lighter or the input voltage becomes higher, that is, the output current becomes smaller and the output voltage becomes higher, the control circuit U reduces the output voltage of the AC output interface 3 by controlling the modulator tube Q to increase the current flowing through the internal consumption resistor R1; when the output load becomes heavier or the input voltage becomes lower, the current on the internal consumption resistor R1 is reduced by the modulator tube Q to increase the output voltage on the AC output interface 3, so that the output voltage of the AC output interface 3 is stabilized within a certain value. By setting the consumption resistor R1, the consumption load current can be effectively adjusted, thereby adjusting the limit value of the current on R1, and realizing the adjustment of the adjustable current limit range; and by the combined setting of the modulator tube Q and the control circuit U, the current flowing through the consumption resistor R1 can be effectively controlled to realize output voltage stabilization control.

[0019] As a specific implementation of the improvement of the modulator tube Q, the modulator tube Q is a triode, the collector of the triode is connected to the end of the consumption resistor R1, the emitter is connected to the output end of the rectifier circuit, and the base is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the current input into the base, so that the current flowing through the consumption resistor R1 can be regulated by the current amplification principle of the triode.

[0020] As another specific implementation of the improvement of the modulator Q, the modulator Q is a field effect tube, the drain of the field effect tube is connected to the end of the consumption resistor R1, the source is connected to the output end of the rectifier circuit, and the gate is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the duty cycle of the square wave input to the gate. By transmitting the PWM signal to the field effect tube Q, the on-time ratio of the modulator Q can be changed by changing the duty cycle of the square wave output by the control circuit U, thereby changing the current flowing through the consumption resistor R1. The output voltage is further stabilized.

[0021] As an improved specific implementation, the power taking circuit 1 includes: A step-down capacitor C, one end of which is connected to one end of an external high-voltage line; A transformer T, the input side of which is connected to the end of the step-down capacitor C, and the other end is connected to the other end of the high-voltage line to form a loop to receive the electric energy stepped down by the step-down capacitor C, and further step down and isolate the electric energy before outputting it through the output side of the transformer T. By setting the step-down capacitor C, the voltage input from the external high-voltage line can be effectively stepped down so that the voltage can be converted by the low-voltage transformer T, and by setting the transformer T, the voltage stepped down by the step-down capacitor C can be further stepped down and isolated before output.

[0022] As an improved specific implementation, the control circuit U is also connected to the AC output interface 3 as a sampling signal of the output voltage to form a closed-loop control, so that the control circuit U can increase the size and accuracy of the current flowing through the consumption resistor R1 to achieve a stable output voltage.

[0023] As a specific implementation of the improvement, the voltage stabilizing circuit 2 is also connected to a diode D and a capacitor C3 to form a loop, and the diode D is also connected in parallel with a resistor R2. In this way, through the combined action of the diode D and the capacitor C3, the internal current harmonics during module operation can be reduced, and the current harmonics on the input side of the transformer T in the power-taking circuit 1 can be further reduced, so that the local discharge amplitude of the high-voltage system can be suppressed in the power-taking system with one end of the high-voltage end grounded, and the interference to peripheral equipment can also be reduced.

[0024] To sum up, the high-voltage capacitor AC power supply of this embodiment adopts a method of directly connecting to the AC output interface 3 on the output side of the transformer T, which can effectively ensure that the AC power output by the AC output interface 3 is a sine wave, and can maximize the reduction of the power conversion process and reduce power loss.

[0025] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A high voltage capacitor AC power supply, characterized in that: include: A power taking circuit (1) is connected to an external high voltage line to receive electric energy from the high voltage line, isolate the electric energy, reduce the voltage and then output it; The rectifier circuit is composed of a rectifier diode Z and capacitors C1 and C2; the rectifier diode Z is connected to the power circuit (1), the capacitor C2 is connected between the rectifier diode Z and the power circuit (1), and the capacitor C1 is connected to the output end of the rectifier diode Z to convert the AC voltage output by the power circuit (1) into a DC voltage; An AC output interface (3), connected between the rectifier diode Z and the power taking circuit (1), for outputting AC power to an external output load; The voltage stabilizing circuit (2) is connected to the rectifier circuit. The voltage stabilizing circuit (2) has a consumption load inside. The current of the internal consumption load is adjusted to control the current size of the circuit loop at the output end of the rectifier diode Z, thereby achieving the stability of the output voltage of the AC output interface (3).

2. The high voltage capacitor AC power supply according to claim 1, characterized in that: The voltage stabilizing circuit (2) reduces the output voltage of the AC output interface (3) by increasing the current flowing through the internal consumption load when the output load becomes lighter, that is, the output current becomes smaller and the output voltage becomes higher; and increases the output voltage of the AC output interface (3) by reducing the current on the internal consumption load when the output load becomes heavier; Alternatively, when the input voltage increases, that is, the output voltage increases, the output voltage of the AC output interface (3) is reduced by increasing the current flowing through the internal consumption load; when the input voltage decreases, the AC output voltage of the output interface (3) is increased by reducing the current on the internal consumption load.

3. The high voltage capacitor AC power supply according to claim 2, characterized in that: The voltage stabilizing circuit (2) comprises: A consumption resistor R1, the consumption resistor R1 is a consumption load, and one end of the consumption resistor R1 is connected to the output end of the rectifier diode Z; The modulation tube Q has a first end connected to the end of the consumption resistor R1, and a second end connected to the other output end of the rectifier diode Z, and forms a current loop with the consumption resistor R1; the control end receives a signal to adjust the current flowing between the consumption resistor R1 and the output end; A control circuit U, which is connected to the control end of the modulation tube Q to send a signal to the control end of the modulation tube Q; Wherein, when the output load becomes lighter or the input voltage becomes higher, that is, the output current becomes smaller and the output voltage becomes higher, the control circuit U controls the modulation tube Q to increase the current flowing through the internal consumption resistor R1 to reduce the output voltage of the AC output interface (3); when the output load becomes heavier or the input voltage becomes lower, the modulation tube Q reduces the current on the internal consumption resistor R1 to increase the output voltage of the AC output interface (3), thereby stabilizing the output voltage of the AC output interface (3) within a certain value.

4. The high voltage capacitor AC power supply according to claim 3 is characterized in that: The modulator Q is a triode, the collector of which is connected to the end of the consumption resistor R1, the emitter is connected to the output end of the rectifier circuit, and the base is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the current input into the base.

5. The high voltage capacitor AC power supply according to claim 3, characterized in that: The modulator tube Q is a field effect tube, the drain of which is connected to the end of the consumption resistor R1, the source is connected to the output end of the rectifier circuit, and the gate is connected to the control circuit U. The control circuit U controls the current flowing through the consumption resistor R1 by changing the duty cycle of the square wave input to the gate.

6. The high-voltage capacitor AC power supply according to any one of claims 1 to 5, characterized in that: The power taking circuit (1) comprises: A high-voltage step-down capacitor C, one end of which is connected to one end of an external high-voltage line; The transformer T has an input side connected to the end of the high-voltage step-down capacitor C, and the other end connected to the other end of the high-voltage line to form a loop to receive the electric energy after the voltage is stepped down by the high-voltage step-down capacitor C, and output the electric energy through the output side of the transformer T after further stepping down and isolating the electric energy.

7. The high-voltage capacitor AC power supply according to any one of claims 2 to 5, characterized in that: The control circuit U is also connected to the AC output interface (3) as a sampling signal of the output voltage to form a closed-loop control.

8. The high-voltage capacitor AC power supply according to any one of claims 1 to 5, characterized in that: The voltage stabilizing circuit (2) is also connected to a diode D and a capacitor C3 to form a loop, and the diode D is also connected in parallel to a resistor R2.

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