Power generation device and power management circuit

Abstract

The embodiment of the invention provides a power generation device, which belongs to the technical field of wind power generation and comprises a swinging module and a power generation module, the swinging module comprises a frame, and the frame is used for swinging when wind resistance comes, so that wind energy is converted into mechanical energy for driving the power generation module to work; the power generation module comprises a plurality of friction nanometer power generation units, and the friction nanometer power generation units are arranged in the main body of the frame; the friction nanometer power generation unit comprises a power generation small ball and a circuit board; a triboelectric material layer is arranged on the surface of the circuit board; the frame swings to drive the small power generation balls to roll, and the small power generation balls rub with the triboelectric material layer of the circuit board to generate electric energy.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a power generation device and a power management circuit. Background Art

[0002] The wake of a car refers to the airflow area formed behind the rear of the car when the car is driving. The airflow characteristics in this area have an important impact on the aerodynamic performance of the car, including aerodynamic drag, lift, and vehicle stability and fuel economy.

[0003] In the prior art, electromagnetic induction power generation devices are usually used to collect wind energy contained in car wakes. However, due to the large changes in air flow velocity and pressure in car wakes, the energy density collected by electromagnetic induction is low, and part of the energy will be lost in the form of heat energy during the conversion process, resulting in low energy conversion efficiency. Summary of the invention

[0004] An object of the embodiments of the present invention is to provide a power generation device and a power management circuit, wherein the power generation device can solve or at least partially solve the above-mentioned defects of the prior art.

[0005] In order to achieve the above-mentioned object, a first aspect of an embodiment of the present invention provides a power generation device, the device comprising: a swing module and a power generation module;

[0006] The swing module includes a frame, and the frame is used to swing when wind resistance comes, so as to convert wind energy into mechanical energy that drives the power generation module to work;

[0007] The power generation module includes a plurality of friction nano power generation units, and the friction nano power generation units are arranged inside the main body of the frame;

[0008] The friction nano power generation unit includes a power generation ball and a circuit board; a friction electric material layer is provided on the surface of the circuit board; the swing of the frame drives the power generation ball to roll, and generates electric energy by friction with the friction electric material layer of the circuit board.

[0009] In some embodiments, the circuit board is a stacked structure, and the middle layer of the circuit board is integrated with electrodes. The swing of the frame drives the power-generating balls to roll, and the electric energy generated by friction with the triboelectric material layer of the circuit board is output through the electrodes.

[0010] In some embodiments, the triboelectric material layer and the substrate are respectively disposed on both sides of the middle layer of the circuit board.

[0011] In some embodiments, the friction nano power generation unit also includes: a side frame; a snap-on is provided on the side frame for fixing the circuit board above and below the side frame; a cavity is formed between the side frame and the circuit board, and the power generation ball is located in the cavity.

[0012] In some embodiments, the power generation module further comprises an electromagnetic power generation unit; the electromagnetic power generation unit comprises a magnet and a coil;

[0013] The magnet is arranged at the lower end of the main body of the frame and is located above the coil; the coil is located at the bottom of the device, and the swing of the frame drives the magnet above the coil to swing, thereby generating a change in magnetic flux in the coil and generating an induced current in the coil.

[0014] In some embodiments, the swing module further comprises a support rod and a bearing;

[0015] The bearing is used to connect the support rod and the frame; the support rod is nested in the bearing; when wind resistance comes, the frame swings around the support rod together with the bearing.

[0016] In some embodiments, the swing module further includes a wind plate; the wind plate is connected to the frame and is used to drive the frame to swing when wind resistance occurs.

[0017] In some embodiments, the wind plate is a curved wind plate.

[0018] In some embodiments, the device further includes a base, which is connected to the frame via the support rod and is used to support the swing module and limit the swing amplitude of the frame.

[0019] A second aspect of an embodiment of the present invention provides a vehicle wake energy collection device, comprising the above-mentioned power generation device, wherein the wind resistance comes from the vehicle wake.

[0020] A third aspect of an embodiment of the present invention provides a power management circuit, which is applied to the power generation device, wherein a first input terminal of the power management circuit is connected to an electric energy output terminal of a friction nano power generation unit of the device, and comprises: a first capacitor, a voltage stabilizing diode, an SCR switch, and a second capacitor;

[0021] The power management circuit first stores the electric energy input by the friction nano power generation unit in the first capacitor. When the voltage of the first capacitor reaches the withstand voltage of the voltage-stabilizing diode, the SCR switch is turned on, the first capacitor is discharged, and the discharge current flows to the second capacitor to store the electric energy in the second capacitor.

[0022] In some embodiments, the power management circuit further includes an inductor;

[0023] The anode of the SCR switch is connected to the first capacitor, the cathode of the SCR is connected to the inductor, and the control electrode of the SCR is connected to the positive electrode of the voltage stabilizing diode.

[0024] In some embodiments, the power management circuit further includes a freewheeling diode;

[0025] The positive electrode of the freewheeling diode is connected to the first capacitor, and the negative electrode of the freewheeling diode is connected to the inductor;

[0026] After the SCR switch is turned on, the first capacitor is discharged, and the discharge current is transmitted to the inductor and the second capacitor;

[0027] After the SCR switch is turned on and the freewheeling diode is turned on, the inductor transfers the stored electric energy to the second capacitor.

[0028] In some embodiments, the power management circuit further includes a first rectifier bridge;

[0029] The first rectifier bridge is connected in parallel with the first capacitor; the electric energy input by the friction nano power generation unit is stored in the first capacitor after being rectified by the first rectifier bridge.

[0030] In some embodiments, the power management circuit further includes a second input terminal and a second rectifier bridge;

[0031] When the power generation module of the device includes an electromagnetic power generation unit, the second input end of the power management circuit is connected to the power output end of the electromagnetic power generation unit, and the electric energy input by the electromagnetic power generation unit is rectified by the second rectifier bridge and stored in the second capacitor.

[0032] The power generation device provided in the embodiment of the present invention can effectively convert wind energy into mechanical energy at low wind speed by swinging the frame structure when wind resistance occurs. It can convert mechanical energy into electrical energy by combining the principle of friction nano-power generation, thereby realizing the effective conversion of mechanical energy into electrical energy, thereby improving the utilization efficiency of wind energy.

[0033] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0035] Figure 1 is a schematic diagram of the overall structure of a power generation device provided by an embodiment of the present invention;

[0036] Figure 2 is a schematic structural diagram of a friction nano power generation unit provided by an embodiment of the present invention;

[0037] Figure 3 is a schematic diagram of a power management circuit provided by an embodiment of the present invention;

[0038] Figure 4 It is a graph of output performance data of a power generation device provided by an embodiment of the present invention at different swing angles.

[0039] Description of Reference Numerals

[0040] 1. Wind board

[0041] 2. Triboelectric nano-power generation unit

[0042] 3. Framework

[0043] 4. Bearings

[0044] 5. Support rod

[0045] 6. Magnets

[0046] 7. Base

[0047] 8. Coil

[0048] 9. Substrate

[0049] 10. Electrode

[0050] 11. Triboelectric material layer

[0051] 12. Side border

[0052] 13. Power generation ball

[0053] 301, first input terminal

[0054] 302. Second input terminal

[0055] 303. The first rectifier bridge

[0056] 304, Second Rectifier Bridge DETAILED DESCRIPTION

[0057] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0058] Embodiment 1

[0059] Figure 1 is a schematic diagram of the overall structure of the power generation device provided by an embodiment of the present invention, such as Figure 1As shown, the device comprises: a swing module and a power generation module;

[0060] The swing module includes a frame 3, and the frame 3 is used to swing when wind resistance comes, so as to convert wind energy into mechanical energy for driving the power generation module to work.

[0061] In some embodiments, the frame 3 is made of a photocurable resin material.

[0062] In some embodiments, the swing module also includes a support rod 5 and a bearing 4; the bearing 4 is used to connect the support rod 5 and the frame 3; the support rod 5 is nested in the bearing 4; the frame 3 swings around the support rod 5 together with the bearing 4 when wind resistance occurs.

[0063] In some embodiments, the bearing is a ceramic bearing, and the bearing adopts an industrial-grade bearing design to ensure the material hardness and structural stability. There are two bearings 4, which are used to connect the support rod 5 and the frame 3 as a swing bearing. The support rod 5 is also used to support the frame 3, and the support rod is made of light-cured resin material 3D printing.

[0064] In some embodiments, the swing module further includes a wind plate 1. The wind plate 1 is connected to the frame 3, and is used to drive the frame to swing when wind resistance comes.

[0065] Specifically, the wind plate 1 is an arc-shaped wind plate, which is located at the top of the entire power generation device and is made of 3D printing using a solid photocurable resin material. It has high solidity and durability and plays a role in bearing the force against the wind. When the arc-shaped wind plate is hit by the wind, it will swing, so that the overall structure of the power generation device and the internal power generation module will swing, which can ensure that the power generation device provided in the embodiment of the present invention still has good power output at low wind speeds.

[0066] In some embodiments, the device further includes a base 7, which is connected to the frame 3 via the support rod 5, and is used to support the swing module and limit the swing amplitude of the frame.

[0067] Specifically, the base and the frame are made of 3D printing, and the material is a light-curing resin material. The base 7 is used to support the entire device and limit its swing amplitude to avoid excessive swing amplitude. When the curved wind plate is swung by external wind resistance, the frame 3 will swing relative to the base 7.

[0068] In some embodiments, the power generation module includes a plurality of friction nano power generation units 2 , and the friction nano power generation units 2 are disposed inside the main body of the frame 3 .

[0069] Specifically, refer to Figure 1The friction nano power generation unit 2 is set in the frame 3, with ten units on the upper and lower sides, arranged in an array, with a total of twenty power generation units.

[0070] Figure 2 is a schematic diagram of the structure of a friction nano power generation unit provided by an embodiment of the present invention, such as Figure 2 As shown, the friction nano power generation unit includes a power generation ball 13 and a circuit board; a friction electric material layer 11 is provided on the surface of the circuit board; the frame 3 swings to drive the power generation ball to roll, and generates electric energy by friction with the friction electric material layer 11 of the circuit board.

[0071] In some embodiments, the power generation ball is a POM (polyoxymethylene) ball, the friction electric material layer 11 is a FEP (polyethylene propylene copolymer) film, the circuit board is a PCB circuit board, and the FEP film is applied to the surface of the circuit board.

[0072] It should be noted that in some embodiments, a square PCB board with a side length of 50 mm is used, and PCB boards of other sizes or other non-conductive materials such as acrylic boards can also be designed as needed.

[0073] The power generation ball can also be made of nylon ball, PTFE ball, aluminum ball, steel ball, PP ball, silicone ball and other materials. The triboelectric material layer can also be made of other dielectric layer materials, such as PTFE, PDMS, Kapton, cellulose, silk fibroin and other membrane materials.

[0074] In some embodiments, the circuit board is a stacked structure, the middle layer of the circuit board is integrated with an electrode 10, the frame 3 swings to drive the power generation ball 13 to roll, and the electric energy generated by friction with the triboelectric material layer 11 of the circuit board is output through the electrode.

[0075] Furthermore, the triboelectric material layer 11 and the substrate 9 are respectively disposed on both sides of the middle layer of the circuit board.

[0076] In some embodiments, the electrodes may be made of metal electrode materials such as gold, silver, tin, etc., or polymer conductive electrodes.

[0077] In some embodiments, the frame swings under the action of wind, driving the POM ball to roll on two copper electrodes with FEP film to generate electrical output. A single generator unit can generate a stable voltage of 220V through friction, with a charging current of up to 1.2uA and a transfer charge of about 70nC. The output signal is finally led out by the copper electrode material on the surface of the PCB circuit board and the wires connected to it.

[0078] In some embodiments, the electrode 10 is a copper electrode, the substrate 9 is made of FR-4 material, and is manufactured integrally with the copper electrode through a PCB bare copper process, and the FEP film is attached to the PCB circuit board.

[0079] The friction between the POM ball and the FEP film forms a high-voltage power generation friction nanogenerator (TENG). The electrodes are led out by copper electrode materials, which can ensure that the friction nanogenerator unit continuously outputs electrical energy.

[0080] In some embodiments, the friction nano power generation unit further includes: a side frame 12. A clip is provided on the side frame 12 for fixing the circuit board above and below the side frame; a cavity is formed between the side frame and the circuit board, and the power generation ball 13 is located in the cavity.

[0081] Specifically, the side frame 12 is designed with a corresponding bayonet that can hold the PCB circuit board. The circuit board is inserted into the side frame 12 through the bayonet, and then the POM ball is placed therein, with a filling rate of 50%. The PCB circuit board is inserted into the other side in the same way, and the distance between the two PCB circuit boards is 2mm, which is exactly the diameter of the POM ball. When the overall structure swings, the POM ball will roll back and forth between the two copper electrodes with FEP film, thereby generating an electrical signal output.

[0082] In some embodiments, the power generation module further includes an electromagnetic power generation unit; the electromagnetic power generation unit includes a magnet 6 and a coil 8.

[0083] Among them, the magnet 6 is arranged at the lower end of the main body of the frame 3 and is located above the coil 8; the coil 8 is located at the bottom of the entire power generation device, and the swing of the frame 3 drives the magnet above the coil to swing, thereby generating a change in magnetic flux in the coil, generating an induced current in the coil, and outputting electricity to the outside.

[0084] In some embodiments, the magnet 6 is made of two circular NdFeB magnets. The two circular NdFeB magnets and a copper coil constitute an electromagnetic generator (EMG). The magnet moves over the coil, thereby generating an induced current in the coil 8 and generating electricity.

[0085] Further experiments have shown that the electromagnetic power generation unit can generate a voltage of 5V and a current of up to 1.5mA.

[0086] An embodiment of the present invention provides a vehicle wake energy collection device, comprising the above-mentioned power generation device, wherein the wind resistance comes from the vehicle wake.

[0087] As one of the candidates for highway energy collection, the vehicle wake energy collection device can be installed on both sides of the highway, and can collect the energy of the wake of passing vehicles and convert this energy into electrical energy to provide the necessary electrical energy for the sensor system or traffic lights. The vehicle wake energy collection device has the following advantages: the ultra-low starting wind speed makes it a candidate device for vehicle wake energy collection; the curved wind plate structure can make full use of the vehicle wake energy; the modular assembly design is adopted, which is easy to replace and ensures the application cost.

[0088] Embodiment 2

[0089] Figure 3 Schematic diagram of a power management circuit provided by an embodiment of the present invention. Figure 3 As shown, the power management circuit provided in the embodiment of the present invention is applied to the power generation device described in the first embodiment, and the first input terminal 301 of the power management circuit is connected to the power output terminal of the friction nano power generation unit (TENG) of the device, including: a first capacitor C in , Zener diode D1, SCR switch, and second capacitor C store .

[0090] The power management circuit first stores the electric energy input by the friction nano power generation unit in the first capacitor C in , when the first capacitor C in When the voltage reaches the withstand voltage of the voltage stabilizing diode D1, the SCR switch (silicon controlled switch) is turned on, and the first capacitor C in Discharge, the discharge current flows to the second capacitor C store , storing the electrical energy in the second capacitor.

[0091] In some embodiments, the first capacitor C in It is a ceramic capacitor.

[0092] In some embodiments, the power management circuit further includes an inductor L.

[0093] The anode of the SCR switch is connected to the first capacitor C in The cathode of the SCR is connected to the inductor, and the control electrode of the SCR is connected to the anode of the voltage stabilizing diode D1.

[0094] In some embodiments, the power management circuit further includes a freewheeling diode D2. The anode of the freewheeling diode D2 is connected to the first capacitor C in The cathode of the freewheeling diode D2 is connected to the inductor L;

[0095] After the SCR switch is turned on, the first capacitor is discharged, and the discharge current is transmitted to the inductor and the second capacitor;

[0096] After the SCR switch is turned on and the freewheeling diode D2 is turned on, the inductor L transfers the stored electrical energy to the second capacitor C store .

[0097] In some embodiments, the power management circuit further includes a first rectifier bridge 304 .

[0098] The first rectifier bridge 303 and the first capacitor C in The electric energy input by the friction nano power generation unit is rectified by the first rectifier bridge and stored in the first capacitor C in .

[0099] Specifically, from the friction nano-electric unit (TENG) to the second capacitor C store The energy transfer between can be simplified into the following three stages:

[0100] Phase 1: The energy collected by TENG is transferred to the first capacitor C in At this stage, the following SCR is disconnected, and the first capacitor C in It is the only load of TENG, and there are no other redundant electronic components to consume energy. The first capacitor C in The voltage across the two ends can quickly rise to its maximum value.

[0101] The second stage: The voltage-stabilizing diode D1 is connected to the cathode and control electrode of the thyristor switch SCR. At this time, the voltage-stabilizing diode D1 acts as a switch to trigger the SCR to close. in When the voltage value of the Zener diode D1 is higher than the threshold voltage of the Zener diode D1, the Zener diode D1 can be turned on. At this time, the first capacitor C in The current will flow to the control electrode of the SCR switch. At the same time, the cathode and anode of the SCR will be turned on, and the energy will enter the next stage. At this time, the first capacitor C in The energy in is transferred to the inductor L and the second capacitor C store When the first capacitor C in When the energy in the capacitor is completely consumed, the phase ends. In the next cycle, the first capacitor C in When the voltage across the two ends is higher than the voltage across the Zener diode D1, the SCR switch will restart, and the cycle will repeat.

[0102] Phase 3: The freewheeling diode D2 begins to conduct. At this time, the inductor L transfers its stored energy to the second capacitor C. store At the same time, the current in the inductor L decreases, and when the current in L decreases to zero, this stage ends. This means that in this stage, all the energy in the inductor L is transferred to the second capacitor C storeAt the end of the third phase, the freewheeling diode D2 stops conducting.

[0103] Through the combined effect of these three stages, the power management circuit achieves efficient transmission and storage of energy. And in each stage, through carefully designed electronic components and circuits, it ensures maximum energy utilization and improves the energy efficiency of the entire system.

[0104] In some embodiments, the power management circuit further includes a second input terminal 302 and a second rectifier bridge 304 .

[0105] When the power generation module of the device includes an electromagnetic power generation unit (EMG), the second input terminal of the power management circuit is connected to the power output terminal of the electromagnetic power generation unit, and the power input by the electromagnetic power generation unit is rectified by the second rectifier bridge 304 and stored in the second capacitor C store .

[0106] The electrical energy generated by the friction nano-electrical generator (TENG) is processed by the power management circuit and stored in the second capacitor C store Inside, the electric energy generated by the electromagnetic generating unit (EMG) is directly converted by the rectifier bridge and stored in the second capacitor C store Finally, it supplies power to electrical appliances.

[0107] The embodiment of the present invention uses a power management circuit and a swing motor to test the output stability of the power generation device. The output performance of the friction nano generator (TENG) and the electromagnetic generator (EMG) at different swing angles is tested respectively. The angle is defined as the angle between the device in the vertical direction and the deflection direction. The following results are obtained through experiments: Figure 4 As shown in the data graph, as the swing angle increases, the triboelectric charge increases from the original 0.2μC to 1.4μC, and the current increases from 1μA to 12μA. As the angle increases, the electrical output performance increases and tends to be stable. The electromagnetic power generation voltage increases from 1.5V to about 5V, and the current increases from 0.4mA to about 1mA.

[0108] The power generation device provided in the embodiment of the present invention can, on the one hand, effectively convert wind energy into mechanical energy at low wind speeds by swinging the frame structure when wind resistance occurs, and can convert mechanical energy into electrical energy signals by combining the principle of friction nano-power generation, thereby realizing effective conversion of mechanical energy into electrical energy, thereby improving the utilization efficiency of wind energy; on the other hand, the circuit management circuit can realize the real-time power supply function for electrical appliances, thereby realizing efficient transmission and storage of the electrical energy output by the power generation device.

[0109] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A power generation device, characterized in that: The device comprises: a swing module and a power generation module; The swing module includes a frame, and the frame is used to swing when wind resistance comes, so as to convert wind energy into mechanical energy that drives the power generation module to work; The power generation module includes a plurality of friction nano power generation units, and the friction nano power generation units are arranged inside the main body of the frame; The friction nano power generation unit includes a power generation ball and a circuit board; a friction electric material layer is provided on the surface of the circuit board; the swing of the frame drives the power generation ball to roll, and generates electric energy by friction with the friction electric material layer of the circuit board.

2. The device according to claim 1, characterized in that The circuit board is a stacked structure, and the middle layer of the circuit board is integrated with electrodes. The swing of the frame drives the power generation ball to roll, and the electric energy generated by friction with the triboelectric material layer of the circuit board is output through the electrodes.

3. The device according to claim 2, characterized in that The triboelectric material layer and the substrate are respectively arranged on both sides of the middle layer of the circuit board.

4. The device according to claim 1, characterized in that The friction nano power generation unit also includes: a side frame; The side frame is provided with a snap-on for fixing the circuit board above and below the side frame; a cavity is formed between the side frame and the circuit board, and the power generation ball is located in the cavity.

5. The device according to claim 1, characterized in that The power generation module further comprises an electromagnetic power generation unit; the electromagnetic power generation unit comprises a magnet and a coil; The magnet is arranged at the lower end of the main body of the frame and is located above the coil; the coil is located at the bottom of the device, and the swing of the frame drives the magnet above the coil to swing, thereby generating a change in magnetic flux in the coil and generating an induced current in the coil.

6. The device according to claim 1, characterized in that The swing module also includes a support rod and a bearing; The bearing is used to connect the support rod and the frame; The support rod is nested in the bearing; When wind resistance comes, the frame swings around the support rod together with the bearing.

7. The device according to claim 6, characterized in that The swing module also includes a wind plate; The wind plate is connected to the frame and is used to drive the frame to swing when wind resistance comes.

8. The device according to claim 7, characterized in that The wind plate is an arc-shaped wind plate.

9. The device according to claim 6, characterized in that The device also includes a base, which is connected to the frame through the support rod and is used to support the swing module and limit the swing amplitude of the frame.

10. A vehicle wake energy collection device, comprising the power generation device according to any one of claims 1 to 9, wherein the wind resistance comes from the vehicle wake.

11. A power management circuit, applied to the device according to any one of claims 1 to 9, wherein a first input terminal of the power management circuit is connected to an electric energy output terminal of a friction nano power generation unit of the device, comprising: A first capacitor, a voltage stabilizing diode, an SCR switch, and a second capacitor; The power management circuit first stores the electric energy input by the friction nano power generation unit in the first capacitor. When the voltage of the first capacitor reaches the withstand voltage of the voltage-stabilizing diode, the SCR switch is turned on, the first capacitor is discharged, and the discharge current flows to the second capacitor to store the electric energy in the second capacitor.

12. The power management circuit according to claim 11, characterized in that: The power management circuit also includes an inductor; The anode of the SCR switch is connected to the first capacitor, the cathode of the SCR is connected to the inductor, and the control electrode of the SCR is connected to the positive electrode of the voltage stabilizing diode.

13. The power management circuit according to claim 12, characterized in that: The power management circuit also includes a freewheeling diode; The positive electrode of the freewheeling diode is connected to the first capacitor, and the negative electrode of the freewheeling diode is connected to the inductor; After the SCR switch is turned on, the first capacitor is discharged, and the discharge current is transmitted to the inductor and the second capacitor; After the SCR switch is turned on and the freewheeling diode is turned on, the inductor transfers the stored electric energy to the second capacitor.

14. The power management circuit according to claim 11, characterized in that: The power management circuit also includes a first rectifier bridge; The first rectifier bridge is connected in parallel with the first capacitor; the electric energy input by the friction nano power generation unit is stored in the first capacitor after being rectified by the first rectifier bridge.

15. The power management circuit according to claim 11, characterized in that: The power management circuit also includes a second input terminal and a second rectifier bridge; When the power generation module of the device includes an electromagnetic power generation unit, the second input end of the power management circuit is connected to the power output end of the electromagnetic power generation unit, and the electric energy input by the electromagnetic power generation unit is rectified by the second rectifier bridge and stored in the second capacitor.

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