Novel single-phase single-tube bidirectional switch hybrid two-level rectifier

Abstract

A novel single-phase single-tube two-way switch hybrid two-level rectifier comprises an alternating current power supply vin, uncontrolled diode bridge arms D1-D4, diodes D5-D12, an inductor L, an inductor L1, an inductor L2, a switch tube S1, a switch tube Sa, a capacitor C and a resistor R. Wherein the diodes D5-D10 and the switch tube S1 form a group of single-tube bidirectional switch units. The hybrid rectifier can realize flexible distribution of energy ratio between two rectifiers connected in parallel, so that the system energy efficiency is further optimized. Compared with a traditional single-phase rectifier, the novel single-phase single-tube bidirectional switch hybrid two-level rectifier provided by the invention has the characteristics of high efficiency, high power density and the like, the device quota and loss are reduced, and the working efficiency of a circuit is greatly improved.

Description

Technical Field

[0001] The invention relates to a two-level rectifier, in particular to a novel single-phase single-tube bidirectional switch hybrid two-level rectifier. Background Art

[0002] With the rapid development of power electronics technology, power conversion technology has become an indispensable part of modern power systems. With the widespread application of renewable energy and the increasing demand for electricity, traditional power conversion technology faces a series of challenges such as low efficiency, high cost, and large size. Therefore, research and development of efficient and compact power conversion equipment has become an important topic in the current power electronics field.

[0003] Modern power electronic equipment has increasingly higher requirements for weight and volume. The defects of traditional rectifiers in these aspects make it difficult for them to meet the needs of new applications. The new hybrid rectifier adopts a more compact design. Through reasonable layout and the application of advanced materials, it significantly reduces the volume and weight, while improving the overall efficiency of the system. This design is not only suitable for home and industrial fields, but also provides strong support for emerging markets such as electric vehicles, wind power generation and photovoltaic power generation. In addition, compared with traditional rectifiers, the new single-tube hybrid rectifier improves the accuracy of current control and voltage regulation by optimizing the control strategy, greatly improving the dynamic response capability of the system. Summary of the invention

[0004] The present invention proposes a novel single-phase single-tube bidirectional switch hybrid two-level rectifier, which has the advantages of simple structure, low cost and flexible control. A single switch tube is used to achieve high-efficiency and high-stability power conversion through precise control strategy. It combines traditional rectification circuits and modern control technology, not only can achieve efficient rectification of DC power supply, but also can maintain efficient and stable output under different load conditions, thereby improving the adaptability and flexibility of electric energy.

[0005] The technical solution adopted by the present invention is:

[0006] A novel single-phase single-tube bidirectional switch hybrid two-level rectifier, the hybrid rectifier comprises:

[0007] Uncontrolled diode bridge arms D1 to D4, diodes D5 to D 12 , inductor L, inductor L1, inductor L2, switch tube S1, switch tube S a , capacitor C, resistor R;

[0008] AC power supplyv in One side is connected to the anode of diode D1, the cathode of diode D2, and one end of inductor L; AC power supply v in The other side is grounded;

[0009] The cathode of the diode D1 and the cathode of the diode D3 are both connected to one end of the inductor L1;

[0010] The anode of the diode D2 and the anode of the diode D4 are both connected to one end of the inductor L2;

[0011] The anode of the diode D3 and the cathode of the diode D4 are both grounded;

[0012] The other end of the inductor L is connected to the anode of the diode D5 and the cathode of the diode D6, respectively, and the connection node thereof constitutes a node a;

[0013] The cathode of the diode D5 is connected to the anode of the diode D7, the drain of the switch tube S1, and the cathode of the diode D9 respectively;

[0014] The anode of diode D6 is connected to the cathode of diode D8, the source of switch tube S1, and the 10 Anode;

[0015] The anode of diode D9, diode D 10 The cathodes of are all grounded, and their connection nodes constitute node n;

[0016] The other end of the inductor L1 is connected to the diode D 11 Anode, switch tube S a Drain;

[0017] The other end of the inductor L2 is connected to the switch tube S a Source, diode D 12 The cathode;

[0018] The cathode of diode D7 is connected to diode D 11 The cathode of, one end of capacitor C, one end of load R;

[0019] The anode of diode D8 is connected to diode D 12 anode, the other end of capacitor C, and the other end of load R.

[0020] The diodes D1, D2, D3 and D4 are connected to form an uncontrolled rectifier circuit.

[0021] The diodes D5 to D 10 , the switch tube S1 is connected to form a group of single-tube bidirectional switch units, which can realize the bidirectional flow function of current.

[0022] A new type of single-phase single-tube bidirectional switch hybrid two-level rectifier includes four working modes:

[0023] Mode 1: Switch S1 is turned on, current flows through inductor L, diode D5, switch S1, diode D 10 After returning to the AC power supply vin ; At this time, the AC power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage U an =0;

[0024] Mode 2: Switch S1 is turned off, and the current flows through inductor L, diode D5, diode D7, capacitor C, diode D8, and diode D 10 After returning to the AC power supply v in ; At this time, the inductance L and the AC power supply v in At the same time, the capacitor C is charged, the inductor current decreases linearly, and the voltage U an =+v o ;

[0025] Mode 3: Switch S1 is turned on, and the current flows through diode D9, switch S1, diode D6, and inductor L before returning to the AC power supply v in ; At this time, the AC power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage U an =0;

[0026] Mode 4: Switch S1 is turned off, and the current flows through diode D9, diode D7, capacitor C, diode D8, diode D6, and inductor L before returning to the AC power supply v in ; At this time, the AC power supply v in As the inductor L charges the capacitor C, the inductor current decreases linearly and the voltage U an =-v o .

[0027] Use diode D 11 , D 12 It allows the current of capacitor C to flow only to load R, ensuring single-phase power flow; at the same time, it acts as a boost clamping diode during mode switching.

[0028] In the 4 working modes, the capacitor voltage v c =v o .

[0029] The present invention discloses a novel single-phase single-tube bidirectional switch hybrid two-level rectifier, which has the following advantages:

[0030] 1. Use a single switch tube through precise control strategy to achieve high-efficiency and high-stability power conversion. It combines traditional rectification circuits and modern control technology, which can not only achieve efficient rectification of DC power supply, but also maintain efficient and stable output under different load conditions, thereby improving the adaptability and flexibility of electric energy.

[0031] 2. Compared with the traditional multi-phase system, the hybrid rectifier has a reduced number of components, simplified control and implementation, and can handle different load conditions in a wide range while ensuring high-efficiency conversion of electrical energy, and can be used in multiple scenarios.

[0032] 3. The new single-phase single-tube bidirectional switch hybrid two-level structure can realize flexible energy distribution between two parallel rectifiers, so that the system energy efficiency is further optimized. Compared with the traditional single-phase rectifier, it has the characteristics of high efficiency and high power density, reduces the device quota and loss, and greatly improves the working efficiency of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0034] Figure 1 This is a circuit schematic diagram of a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier.

[0035] Figure 2 This is a schematic diagram of the current path of the new single-phase single-tube bidirectional switch hybrid two-level rectifier in working mode 1.

[0036] Figure 3 This is a schematic diagram of the current path of the new single-phase single-tube bidirectional switch hybrid two-level rectifier in working mode 2.

[0037] Figure 4 This is a schematic diagram of the current path of the new single-phase single-tube bidirectional switch hybrid two-level rectifier in working mode 3.

[0038] Figure 5 This is a schematic diagram of the current path of the new single-phase single-tube bidirectional switch hybrid two-level rectifier operating mode 4.

[0039] Figure 6 The input voltage v is the new single-phase single-tube bidirectional switch hybrid two-level rectifier in , current i1 waveform.

[0040] Figure 7 The input voltage v is the new single-phase single-tube bidirectional switch hybrid two-level rectifier in , current i2 waveform.

[0041] Figure 8 The total input voltage v of the new single-phase single-tube bidirectional switch hybrid two-level rectifier is in 、Current i in Waveform graph.

[0042] Fig. 9 The bridge arm voltage U is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit an Waveform graph.

[0043] Fig.10 The voltage across the load R of the new single-phase single-tube bidirectional switch hybrid two-level rectifier is v o Waveform graph.

[0044] Fig.11 The output DC voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier when the load R is halved o Waveform graph. DETAILED DESCRIPTION

[0045] like Figure 1 As shown, a novel single-phase single-tube bidirectional switch hybrid two-level rectifier, the hybrid rectifier comprises:

[0046] Uncontrolled diode bridge arms D1 to D4, diodes D5 to D 12 , inductor L, inductor L1, inductor L2, switch tube S1, switch tube S a , capacitor C, resistor R;

[0047] AC power supplyv in One side is connected to the anode of diode D1, the cathode of diode D2, and one end of inductor L; AC power supply v in The other side is grounded;

[0048] The cathode of the diode D1 and the cathode of the diode D3 are both connected to one end of the inductor L1;

[0049] The anode of the diode D2 and the anode of the diode D4 are both connected to one end of the inductor L2;

[0050] The anode of the diode D3 and the cathode of the diode D4 are both grounded;

[0051] The other end of the inductor L is connected to the anode of the diode D5 and the cathode of the diode D6, respectively, and the connection node thereof constitutes a node a;

[0052] The cathode of the diode D5 is connected to the anode of the diode D7, the drain of the switch tube S1, and the cathode of the diode D9 respectively;

[0053] The anode of diode D6 is connected to the cathode of diode D8, the source of switch tube S1, and the 10 Anode;

[0054] The anode of diode D9, diode D 10 The cathodes of are all grounded, and their connection nodes constitute node n;

[0055] The other end of the inductor L1 is connected to the diode D 11 Anode, switch tube S a Drain;

[0056] The other end of the inductor L2 is connected to the switch tube S a Source, diode D 12 The cathode;

[0057] The cathode of diode D7 is connected to diode D 11 The cathode of, one end of capacitor C, one end of load R;

[0058] The anode of diode D8 is connected to diode D 12 anode, the other end of capacitor C, and the other end of load R.

[0059] The diodes D1, D2, D3 and D4 are connected to form an uncontrolled rectifier circuit.

[0060] The diodes D5 to D 10 , the switch tube S1 is connected to form a group of single-tube bidirectional switch units, which can realize the bidirectional flow function of current.

[0061] The specific working principle of a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit of the present invention is described below. The two-level rectifier has four working modes, among which: capacitor voltage v c =v o , the specific analysis process is as follows:

[0062] Figure 2 Schematic diagram of the current path in mode 1: switch tube S1 is turned on, and the current flows through inductor L, diode D5, switch tube S1, and diode D 10 After returning to power supply v in ; At this time, the power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage U an =0;

[0063] Figure 3 Schematic diagram of the current path in mode 2: switch tube S1 is turned off, and the current flows through inductor L, diode D5, diode D7, capacitor C, diode D8, and diode D 10 After returning to power supply v in ; At this time, the inductor L and the power supply v in At the same time, the capacitor C is charged, the inductor current decreases linearly, and the voltage U an =+v o ;

[0064] Figure 4 This is a schematic diagram of the current path in mode 3: the switch tube S1 is turned on, and the current flows through the diode D9, the switch tube S1, the diode D6, the inductor L, and then returns to the power supply v in ; At this time, the power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage Uan =0;

[0065] Figure 5 This is a schematic diagram of the current path in mode 4: the switch tube S1 is turned off, and the current flows through the diode D9, the diode D7, the capacitor C, the diode D8, the diode D6, the inductor L and then returns to the power supply v in ; At this time, the power supply v in As the inductor L charges the capacitor C, the inductor current decreases linearly and the voltage U an =-v o ;

[0066] Table 1 shows the pulse distribution mode of the rectifier switch tube, the working state of the DC side capacitor and the voltage U an Correspondence table, where the on and off of the switch tube are represented by "1" and "0" respectively.

[0067] Table 1 Rectifier switch pulse distribution mode, DC side capacitor working state and voltage U an Correspondence table

[0068]

[0069] In order to verify that a novel single-phase single-tube hybrid two-level rectifier of the present invention can realize the two-level function, experimental verification is carried out under a single-cycle control strategy. The experimental parameters are: AC power supply frequency is 50Hz, input voltage effective value is 220V, inductance L=50mH, capacitance is 22000uF, switching frequency is 10kHz, boost inductance L1=L2=2mH, load is 50Ω.

[0070] Figure 6 The voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit in , Input current i1 waveform diagram, input current i1 can effectively follow the AC input voltage v in , further reducing the harmonic content of the input side current and realizing the power factor correction function.

[0071] Figure 7 The voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit in , Input current i2 waveform diagram, input current i2 can effectively follow the AC input voltage v in , further reducing the harmonic content of the input side current and realizing the power factor correction function.

[0072] Figure 8 The voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit in 、Input measurement total current i in Waveform, input current i in Can effectively follow the AC input voltage v in, further reducing the harmonic content of the input side current and realizing the power factor correction function.

[0073] Fig. 9 The bridge arm voltage U of the new single-phase single-tube bidirectional switch hybrid two-level rectifier circuit is an From the waveform, we can see that the voltage is alternating between positive and negative and is almost symmetrical. The two-level effect is good, and the experimental verification and theoretical analysis results are consistent. The two-level is the output terminal potential of 0, v o Two types.

[0074] Fig.10 The output DC voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit o Waveform diagram, the present invention designs a two-level rectifier with input 220V / output 400V, Fig.10 The waveform shows that the voltage v o Stable output.

[0075] Fig.11 The output DC voltage v is a new type of single-phase single-tube bidirectional switch hybrid two-level rectifier circuit when the load is halved o Waveform, output DC voltage v o The waveform is slightly adjusted at 0.25s to 0.3s and quickly returns to a stable state, indicating that the system has strong dynamic adjustment capability and good anti-disturbance performance.

[0076] The hybrid rectifier can realize flexible energy distribution between two parallel rectifiers, so that the energy efficiency of the system is further optimized.

[0077] Compared with the traditional single-phase rectifier, the novel single-phase single-tube bidirectional switch hybrid two-level rectifier proposed by the present invention has the characteristics of high efficiency and high power density, reduces the device rating and loss, and greatly improves the working efficiency of the circuit.

Claims

1. A new type of single-phase single-tube bidirectional switch hybrid two-level rectifier, characterized in that The hybrid rectifier comprises: Uncontrolled diode bridge arms D1 to D4, diodes D5 to D 12 , inductor L, inductor L1, inductor L2, switch tube S1, switch tube S a , capacitor C, resistor R; AC power supplyv in One side is connected to the anode of diode D1, the cathode of diode D2, and one end of inductor L; AC power supply v in The other side is grounded; The cathode of the diode D1 and the cathode of the diode D3 are both connected to one end of the inductor L1; The anode of the diode D2 and the anode of the diode D4 are both connected to one end of the inductor L2; The anode of the diode D3 and the cathode of the diode D4 are both grounded; The other end of the inductor L is connected to the anode of the diode D5 and the cathode of the diode D6, respectively, and the connection node thereof constitutes a node a; The cathode of the diode D5 is connected to the anode of the diode D7, the drain of the switch tube S1, and the cathode of the diode D9 respectively; The anode of diode D6 is connected to the cathode of diode D8, the source of switch tube S1, and the 10 Anode; The anode of diode D9, diode D 10 The cathodes of are all grounded, and their connection nodes constitute node n; The other end of the inductor L1 is connected to the diode D 11 Anode, switch tube S a Drain; The other end of the inductor L2 is connected to the switch tube S a Source, diode D 12 The cathode; The cathode of diode D7 is connected to diode D 11 The cathode of, one end of capacitor C, one end of load R; The anode of diode D8 is connected to diode D 12 anode, the other end of capacitor C, and the other end of load R.

2. According to claim 1, a novel single-phase single-tube bidirectional switch hybrid two-level rectifier is characterized in that: The diodes D1, D2, D3 and D4 are connected to form an uncontrolled rectifier circuit.

3. According to claim 1, a novel single-phase single-tube bidirectional switch hybrid two-level rectifier is characterized in that: The diodes D5 to D 10 , the switch tube S1 is connected to form a group of single-tube bidirectional switch units.

4. A novel single-phase single-tube bidirectional switch hybrid two-level rectifier as claimed in any one of claims 1 to 3, characterized in that: Includes 4 working modes: Mode 1: Switch S1 is turned on, current flows through inductor L, diode D5, switch S1, diode D 10 After returning to the AC power supply v in ; At this time, the AC power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage U an =0; Mode 2: Switch S1 is turned off, and the current flows through inductor L, diode D5, diode D7, capacitor C, diode D8, and diode D 10 After returning to the AC power supply v in ; At this time, the inductance L and the AC power supply v in At the same time, the capacitor C is charged, the inductor current decreases linearly, and the voltage U an =+v o ; Mode 3: Switch S1 is turned on, and the current flows through diode D9, switch S1, diode D6, and inductor L before returning to the AC power supply v in ; At this time, the AC power supply v in The inductor L is charged to store energy, the inductor current increases linearly, the load R is powered by the capacitor C, and the voltage U an =0; Mode 4: Switch S1 is turned off, and the current flows through diode D9, diode D7, capacitor C, diode D8, diode D6, and inductor L before returning to the AC power supply v in ; At this time, the AC power supply v in As the inductor L charges the capacitor C, the inductor current decreases linearly and the voltage U an =-v o .

5. According to claim 4, a novel single-phase single-tube bidirectional switch hybrid two-level rectifier is characterized in that: Use diode D 11 , D 12 It allows the current of capacitor C to flow only to load R, ensuring single-phase power flow; at the same time, it acts as a boost clamping diode during mode switching.

6. According to claim 4, a novel single-phase single-tube bidirectional switch hybrid two-level rectifier is characterized in that: In the four working modes, the capacitor voltage v c =v o .

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