CN102983730A - Direct-current harmonic suppression system and method of double reversed star-like rectification system - Google Patents

Abstract

The invention relates to a DC side harmonic suppression system and method of a double-inverse star rectification system, belonging to the technical field of power electronics. The invention solves the problem that the nonlinearity of the existing double-inverse star rectification system will cause it to generate a large number of harmonics, and the installation of a harmonic compensation device on the AC side will increase the volume and capacity of the system. In the present invention, the synchronous circuit collects the reference triangular wave signal. In the control circuit, the signal is multiplied by the current of the collected load loop to obtain a current reference signal. The current reference signal is compared with the collected current to generate a drive signal, and the PWM The drive signal is sent to the drive circuit; the drive circuit amplifies the power of the received PWM drive signal and outputs it to the triple frequency current triangle wave inverter circuit to adjust the secondary side current value of the balance reactor, and make the secondary side current value through the current closed-loop control. The secondary current value of the balance reactor is 0.5 times of the load loop current value. The invention is suitable for the harmonic suppression of the double anti-star rectification system.

Description

Harmonic Suppression System and Method for DC Side of Double Inverted Star Rectification System

technical field

The invention relates to a DC-side harmonic suppression system and method of a double-inverted star-shaped rectification system, belonging to the technical field of power electronics.

Background technique

In industrial applications such as electrolytic plating, low-voltage and high-current DC power supplies are often required. As a common low-voltage and high-current rectification system, the double-inverted star rectification system, in these low-voltage and high-current (such as tens of volts to tens of volts, several Hundreds of amps to tens of thousands of amps) occasions have been widely used. Due to the nonlinearity of this rectification system, it will generate a large number of harmonics, reduce the power factor of the system, and cause serious harmonic pollution to the power grid.

At present, the main method to solve the problem of harmonic pollution in the high-power double-inverse star rectification system in the prior art is to compensate the harmonics generated by the rectification system by installing a harmonic compensation device, such as using various active, passive and hybrid Type filter to compensate the harmonics generated by the rectification system, this method is applicable to the harmonics generated by various harmonic sources. But in many occasions, the power level of the filter is not much different from that of the rectification system, which will not only increase the capacity and volume of the entire system, but also increase system loss and cost. The method of installing a harmonic compensation device to compensate the harmonics generated by the rectification system is to suppress the harmonics after they are generated. At this time, the impact of the harmonics on the system has already occurred. A more reasonable harmonic suppression method should be able to actively suppress the generation of harmonics, eliminate the impact of harmonics on the system, and at the same time not increase or increase the capacity and volume of the system as little as possible.

Contents of the invention

In order to solve the problem that the nonlinearity of the existing double-inverse star rectification system will cause it to generate a large number of harmonics and the installation of a harmonic compensation device on the AC side will increase the volume and capacity of the system, a double-inverse star rectification system is proposed. A harmonic suppression system and method for a DC side of a rectification system.

The DC side harmonic suppression system of the double inverse star rectification system includes a balanced reactor with a secondary side, a triple frequency current triangular wave inverter circuit, a drive circuit, a signal processing and control circuit, a balanced reactor secondary side current sensor, and a synchronous circuit and load loop current sensors,

The primary coil of the balanced reactor with the secondary side is connected in parallel between the positive output ends of the two sets of three-phase half-wave rectifier bridges of the double inverse star rectifier circuit, and the middle tap of the primary coil of the balanced reactor with the secondary side is connected The positive polarity output terminal of the load power supply, the secondary coil of the balance reactor with the secondary side are connected in parallel to the AC input side of the triple frequency current triangular wave inverter circuit, and the positive and negative output terminals of the DC side of the triple frequency current triangular wave inverter circuit respectively connected to the positive output terminal of the load power supply and the negative output terminal of the load power supply,

The first signal input end of the synchronous circuit is connected to the opposite end of the first secondary coil of the double anti-star rectification system, and the second signal input end of the synchronous circuit is connected to the opposite end of the second secondary coil of the double anti-star rectification system connected, the third signal input end of the synchronous circuit is connected with the opposite end of the third secondary side coil of the double inverse star rectification system, the output end of the synchronous circuit is connected with the synchronous reference signal input end of the signal processing and control circuit,

The load circuit current sensor is used to detect the current between the middle taps of the primary side coil of the balance reactor with the secondary side of the positive polarity output terminal of the load power supply, and the current signal output terminal of the load circuit current sensor is connected to the load of the signal processing and control circuit loop current signal input,

The reactor secondary current sensor is used to detect the current of the secondary coil of the balanced reactor with secondary side. The current signal output terminal of the reactor secondary current sensor is connected to the reactor secondary current signal input terminal of the signal processing and control circuit.

The control signal output end of the signal processing and control circuit is connected to the control signal input end of the drive circuit, and the drive signal output end of the drive circuit is connected to the drive signal input end of the triple frequency current triangle wave inverter circuit.

The method of harmonic suppression using the DC side harmonic suppression system of the double reverse star rectification system is as follows: connect the load to the positive output terminal of the load power supply of the double reverse star rectification system and the load power supply of the double reverse star rectification system Between the negative output terminals of the negative polarity, the synchronous circuit collects the line voltage signal of the secondary side of the double anti-star transformer, and generates a reference triangular wave signal after filtering and signal processing, and the reference triangular wave signal is input into the signal processing and control circuit.

The signal processing and control circuit multiplies the received reference triangular wave signal with the load loop current signal detected by the load loop current sensor to generate a current reference signal, which is compared with the detected secondary side current of the balanced reactor with secondary side After the signal is compared, after the signal processing and the controller processing of the control circuit, a PWM driving signal is generated, and the PWM driving signal is sent to the driving circuit;

The drive circuit amplifies the power of the received PWM drive signal and outputs it to the triple frequency current triangle wave inverter circuit to adjust the secondary current value of the balanced reactor, and make the secondary current of the balanced reactor with secondary side through the current closed-loop control The value is 0.5 times of the current value of the load loop, that is, the harmonic suppression of the double anti-star rectification system is realized.

The harmonic and harmonic suppression system of the present invention extracts the harmonic energy of the original double inverse star rectification system through the secondary side of the balanced reactor with secondary side, and transforms the triple frequency current triangular wave inverter circuit in the secondary side The secondary side of the balance reactor obtains a required small-capacity current source, through which the current on the AC side is affected, and the harmonics of the input current on the AC side are suppressed on the DC side.

The system has a simple structure and can actively suppress the current harmonics input by the AC side of the double-inverted star rectification system. After adding the harmonic suppression system of the present invention to the DC side of the original double-inverted star rectifier system, the THD of the input current on the AC side is changed from the original 30% of the original rectification system is reduced to about 3%, and the harmonic suppression system capacity of the present invention is only about 8% of the rectification system capacity, which will not cause a large increase in the volume and capacity of the original double reverse star rectification system .

Description of drawings

Figure 1 is a schematic diagram of the circuit structure of a double inverse star rectification system with a DC side harmonic suppression system;

2 is a structural diagram of a triple frequency current triangular wave inverter circuit using a half-bridge structure as described in Embodiment 2;

FIG. 3 is a structural diagram of a triple-frequency current triangular wave inverter circuit using a full-bridge structure as described in Embodiment 3;

4 is a curve diagram of the unipolar working process of the method for suppressing harmonics on the DC side described in Embodiment 4;

Fig. 5 is a curve diagram of the bipolar working process of the method for suppressing harmonics on the DC side described in Embodiment 4;

Figures 6 to 9 are schematic diagrams of current loops corresponding to the four periods in the working process graph shown in Figure 4 in the unipolar working state of the triple frequency current triangular wave inverter circuit, wherein:

Fig. 6 represents the current loop schematic diagram of 0 to _t1 section;

Fig. 7 represents the current loop schematic diagram of _t1 to _t2 section;

Fig. 8 represents the current loop schematic diagram of t ₂ to t ₃ sections;

Fig. 9 represents the current loop schematic diagram of t ₃ to t ₄ sections;

Figures 10 to 13 are schematic diagrams of current loops corresponding to the four periods in the working process graph shown in Figure 5 in the bipolar working state of the triple frequency current triangular wave inverter circuit, wherein:

Fig. 10 represents the current loop schematic diagram of 0 to _t1 section;

Fig. 11 represents the current loop schematic diagram of _t1 to _t2 section;

Fig. 12 represents the current loop schematic diagram of t ₂ to t ₃ sections;

Fig. 13 shows a schematic diagram of the current loop from _t3 to _t4 .

Detailed ways

Specific Embodiment 1: This embodiment is described in conjunction with FIG. 1. The DC-side harmonic suppression system of the double-reverse star rectification system described in this embodiment is installed on the DC side of the original double-reverse star rectification system. The harmonic suppression system on the DC side of the rectangular rectification system includes a balanced reactor 1 with a secondary side, a triple frequency current triangular wave inverter circuit 2, a drive circuit 3, a signal processing and control circuit 4, a current sensor 5 on the secondary side of the balanced reactor, Synchronization circuit 6 and load loop current sensor 7,

The primary side coil of the balanced reactor 1 with secondary side is connected in parallel between the positive polarity output terminals M and P of two sets of three-phase half-wave rectifier bridges in the double reverse star rectifier circuit, and the primary side of the balanced reactor 1 with secondary side The middle tap of the coil is connected to the positive polarity output terminal P of the load power supply, and the secondary coil of the balance reactor 1 with the secondary side is connected in parallel to the AC input side of the triple frequency current triangular wave inverter circuit 2, and the triple frequency current triangular wave inverter circuit The positive and negative output terminals of the DC side of 2 are respectively connected to the positive output terminal P and the negative output terminal N of the load power supply,

The first signal input end of the synchronous circuit 6 is connected with the opposite end of the first secondary side coil of the double anti-star rectification system, and the second signal input end of the synchronous circuit 6 is connected with the opposite end of the second secondary side coil of the double anti-star rectification system. The terminal is connected, the third signal input terminal of the synchronous circuit 6 is connected with the opposite terminal of the third secondary side coil of the double inverse star rectification system, and the output terminal of the synchronous circuit 6 is connected to the synchronous reference signal input terminal of the signal processing and control circuit 4 ,

The load loop current sensor 7 is used to detect the current between the positive polarity output terminal P of the load power supply and the middle tap of the primary side coil of the balanced reactor 1 with the secondary side, and the current signal output terminal of the load loop current sensor 7 is connected to the signal processing and the load loop current signal input end of the control circuit 4,

The reactor secondary current sensor 5 is used to detect the current of the secondary coil of the balanced reactor 1 with the secondary side, and the current signal output terminal of the reactor secondary current sensor 5 is connected to the reactor secondary current of the signal processing and control circuit 4 signal input,

The control signal output end of the signal processing and control circuit 4 is connected to the control signal input end of the drive circuit 3 , and the drive signal output end of the drive circuit 3 is connected to the drive signal input end of the triple frequency current triangle wave inverter circuit 2 .

The harmonic suppression system described in this embodiment is installed on the DC side of the original double-inverted star rectifier system. The original double-inverted star rectifier system is connected to the grid through a double-inverted star-shaped transformer. Connect two three-phase half-wave rectifier bridges, one end of the primary side of the balanced reactor 1 with the secondary side is connected to the double inverse star rectifier circuit, the positive output terminal M of a three-phase half-wave rectifier bridge, and the balanced reactor 1 with the secondary side The other end of the original side of the double inverse star rectifier circuit is connected to the positive output terminal Q of another three-phase half-wave rectifier bridge, the input end of the synchronous circuit 6 is connected to the line voltage signal output end of the secondary side of the double inverse star transformer, and the load 8 is connected to Between the positive output terminal P of the load power supply of the double inverse star rectification system and the negative output terminal N of the load power supply of the double inverse star rectification system.

Specific embodiment 2: This embodiment is a further limitation of the DC side harmonic suppression system of the double inverse star rectification system described in specific embodiment 1. The triple frequency current triangular wave inverter circuit 2 adopts a half bridge or a full bridge bridge structure.

Specific embodiment 3: This embodiment is a further limitation of the DC side harmonic suppression system of the double inverse star rectification system described in specific embodiment 1. The triple frequency current triangular wave inverter circuit 2 adopts a full bridge structure, Moreover, the triple frequency current triangular wave inverter circuit 2 adopts a unipolar or bipolar PWM control mode.

Embodiment 4: Refer to Fig. 2 to illustrate this embodiment. This embodiment is a further limitation of the DC side harmonic suppression system of the double inverse star rectification system described in Embodiment 1. The triple frequency current triangular wave inverse The variable circuit 2 is a half-bridge structure, and the circuit consists of the first inductor L _1N , the first switch tube S ₁₁ , the first diode D ₁₁ , the first capacitor C ₁₁ , the first resistor R ₁₁ , the first three The switch tube S ₁₃ , the first and third diodes D ₁₃ , the first and third capacitors C ₁₃ , the first and third resistors R ₁₃ , the first and second capacitors C 12 , the first and second resistors R ₁₂ , the first and fourth capacitors C ₁₄ and the first and third capacitors C ₁₄ Composed of four resistors R ₁₄ , one end of the first inductance L _1N is connected to one end of the secondary coil of the balance reactor 1 with a secondary side, and the other end of the first inductance L _1N is connected to the first diode D ₁₁ at the same time The anode, one end of the first one switch tube _S11 , one end of the first one resistor _R11 , one end of the first three switch tube _S13 , the cathode of the first three diodes _D13 , and one end of the first three capacitors _C13 are connected , the other end of the first one switch tube S ₁₁ is simultaneously connected with the cathode of the first one diode D ₁₁ , one end of the first one capacitor C ₁₁ , one end of the first two capacitors C ₁₂ , and one end of the first two resistors R ₁₂ It is connected to the positive polarity output terminal P of the load power supply, the other end of the first resistor R ₁₁ is connected to the other end of the first capacitor C ₁₁ , and the negative polarity output terminal N of the load power supply is connected to one end of the first fourth resistor R ₁₄ at the same time. , one end of the first fourth capacitor _C14 , one end of the first third resistor _R13 , the anode of the first third diode _D13 and the other end of the first third switch _S13 are connected, and the other end of the first fourth resistor _R14 One end is simultaneously connected with the other end of the first and second resistors R ₁₂ , the other end of the first and fourth capacitors C ₁₄ , the first and second capacitors C ₁₂ and the other end of the secondary coil of the balance reactor 1 with the secondary side, the first three The other end of the capacitor C ₁₃ is connected to the other end of the first third resistor R ₁₃ .

Fig. 2 shows that the triple frequency current triangular wave inverter circuit 2 described in this embodiment is in the working state, when the secondary side output of the balance reactor 1 on the secondary side is in the state shown in Fig. 2, that is: the upper end of the coil is positive, When the lower end is negative, the current direction in the first inductor L _1N is the direction shown by the arrow in the figure, and the voltage across the first inductor L _1N is in the state shown in the figure.

Embodiment 5: Refer to FIG. 3 to illustrate this embodiment. This embodiment is a further limitation of the DC-side harmonic suppression system of the double inverse star rectification system described in Embodiment 1. The triple frequency current triangular wave inversion The variable circuit circuit 2 is a full-bridge controllable rectification circuit, and the full-bridge controllable rectification circuit is composed of a second inductor L _2N , a second-first switching tube S ₂₁ , a second-first diode D ₂₁ , and a second-first capacitor C ₂₁ , the second and third resistors R ₂₁ , the second and third switch tubes S ₂₃ , the second and third diodes D ₂₃ , the second and third capacitors C ₂₃ , the second and third resistors R ₂₃ , the second and second switch tubes S ₂₂ , the second and second Diode D ₂₂ , second and second capacitors C ₂₂ , second and second resistors R ₂₂ , second and fourth switch _tubes S ₂₄ , second and fourth diodes D 24 , second and fourth capacitors C ₂₄ and second and fourth resistors R ₂₄ composition,

One end of the second inductance L _2N is connected to one end of the secondary coil of the balance reactor 1 with the secondary side, and the other end of the second inductance L _2N is simultaneously connected to one end of the second-first switching tube S ₂₁ and the second-first diode The anode of D ₂₁ , one end of the second one resistor R ₂₁ , one end of the second three switch tube S ₂₃ , the cathode of the second three diode D ₂₃ and one end of the second three capacitor C ₂₃ are connected, and the second one switch tube The other end of S ₂₁ is simultaneously connected with the cathode of the second-first diode D ₂₁ , one end of the second-first capacitor C ₂₁ , one end of the second-second switching tube S ₂₂ , the cathode of the second-second diode D ₂₂ , the second One end of the second capacitor C ₂₂ is connected to the positive output terminal P of the load power supply, the other end of the second capacitor C ₂₁ is connected to the other end of the second resistor R ₂₁ , and the other end of the second capacitor C ₂₂ is connected to the second One end of the second resistor R ₂₂ is connected, and the other end of the second resistor R ₂₂ is simultaneously connected to the other end of the second switch tube S ₂₂ , the anode of the second diode D ₂₂ , and the balance reactor 1 with the secondary side. The other end of the secondary coil, one end of the second four switch tube S ₂₄ , the cathode of the second four diode D ₂₄ , and one end of the second four capacitor C 24 are connected, and the other end of the second four capacitor C ₂₄ is connected to the second four capacitor C ₂₄ . One end of the resistor R ₂₄ is connected, and the other end of the second fourth resistor R ₂₄ is simultaneously connected to the other end of the second fourth switch tube S ₂₄ , the anode of the second fourth diode D ₂₄ , the negative output terminal N of the load power supply, the second The other end of the third switching tube S ₂₃ , the anode of the second third diode D ₂₃ , and one end of the second third resistor R ₂₃ are connected, and the other end of the second third resistor R ₂₃ is connected to the other end of the second third capacitor C ₂₃ .

Fig. 3 shows that the triple frequency current triangular wave inverter circuit 2 described in this embodiment is in the working state, when the secondary side output of the balance reactor 1 on the secondary side is in the state shown in Fig. 3, that is: the upper end of the coil is positive, When the lower end is negative, the direction of the current in the second inductor L _2N is the direction shown by the arrow in the figure, and the voltage at both ends of the second inductor L _2N is in the state shown in the figure.

The triple-frequency current triangular wave inverter circuit 2 is a full-bridge structure, which defines that the output of the secondary side of the balance reactor 1 with a secondary side is a positive pole, and the output of the other end is a negative pole. The triple frequency current triangular wave inverter circuit using the full bridge structure is shown in Figure 3.

Embodiment 6: This embodiment is a further limitation of the harmonic suppression system on the DC side of the double inverse star rectification system described in Embodiment 4 or 5, and the switching tube is MOSFET or IGBT.

The MOSFET or IGBT has its own body diode, and each pair of diodes and switch tubes in the triple frequency current triangular wave inverter circuit with a full bridge structure can be replaced by a MOSFET or IGBT with a body diode.

Embodiment 7: The method for realizing harmonic suppression by using the DC-side harmonic suppression system of the double-inverted star rectification system described in Embodiment 1 is: connect the load 8 to the positive pole of the load power supply of the double-inverted star rectifier system Between the polarity output terminal P and the negative polarity output terminal N of the load power supply of the double inverse star rectification system, the synchronous circuit 6 collects the line voltage signal of the secondary side of the double inverse star transformer, and generates a reference triangular wave signal after filtering and signal processing. The reference triangular wave signal is input into the signal processing and control circuit 4,

The signal processing and control circuit 4 multiplies the received reference triangular wave signal with the load loop current signal detected by the load loop current sensor 7 to generate a current reference signal, which is compared with the detected balance reactor 1 with secondary side After the secondary side current signals are compared, after signal processing and processing by the controller of the control circuit, a PWM driving signal is generated, and the PWM driving signal is sent to the driving circuit 3;

The drive circuit 3 amplifies the power of the received PWM drive signal and outputs it to the triple frequency current triangular wave inverter circuit 2, adjusts the secondary side current value of the balanced reactor 1, and makes the balanced reactor 1 with the secondary side through the current closed-loop control The secondary side current value is 0.5 times of the load circuit current value, that is, to realize the harmonic suppression of the double anti-star rectification system.

The zero-crossing point of the secondary-side current of the balanced reactor 1 with secondary side coincides with the zero-crossing point of the output phase voltage of the secondary side of the double-flying star transformer.

Embodiment 8: Refer to Figures 4, 6, 7, 8 and 9 to illustrate this embodiment. This embodiment is a further limitation of the harmonic suppression method described in Embodiment 7. The triple frequency current triangle wave inverter circuit Using a full-bridge structure and using a unipolar control method,

When the unipolar control method is adopted, the triple-frequency current triangular wave inverter circuit has four working modes in half a cycle, and the four working modes of the positive half cycle are introduced in turn starting from time 0:

Section 0 to t ₁ : at time 0, turn on the second and third switching tubes S ₂₃ , the second and third switching tubes S ₂₃ and the second and fourth diodes D ₂₄ are turned on together, and the secondary side voltage of the balance reactor with secondary side U _s is added to the second inductance L _2N , the current i _s of the second inductance L _2N flows forward and rises from zero, the second inductance L _2N stores energy, and there is no energy exchange on the AC and DC sides at this time,

From t ₁ to t ₂ : At time t ₁ , turn on the second and second switching tubes S ₂₂ , at this time the second and third switching tubes S ₂₃ and the second and second switching tubes S ₂₂ are turned on together, and the balance reactor with the secondary side The secondary voltage u _s and the voltage on the load are applied to the second inductance L _2N together, the current i _s of the second inductance L _2N rises rapidly, the second inductance L _2N continues to store energy, and at this time both the AC and DC sides output energy to the The second inductive energy storage,

Section t ₂ to t ₃ : at time t ₂ , turn off the second and third switching tubes S ₂₃ , and the second and first diodes D ₂₁ freewheel. At this time, the second and second switching tubes S ₂₂ and the second and first diodes D ₂₁ are turned on together, the secondary voltage u _s of the balanced reactor with secondary side is added to the second inductance L _2N , the current i _s of the second inductance L _2N continues to rise, and the second inductance L _2N continues to store energy, at this time There is no energy exchange on the AC and DC sides,

From _t3 to _t4 : at time _t3 , turn off the second and second switch S ₂₂ , and turn on the second forty-two switch D ₂₄ . At this time, the second forty-two switch D ₂₄ and the second one-two switch D _{and 21} are turned on together, the secondary voltage u _s of the balance reactor with secondary side and the inductance supply power to the load, the current i _s of the second inductance L _1N starts to drop, and the second inductance L _1N continues to store energy, at this time the AC side and inductive energy transfer to the load.

This embodiment is an introduction to the working mode of the triple-frequency current triangular wave inverter circuit 2 with a full-bridge structure. When the circuit is in the positive half cycle and negative half cycle of the alternating current, the circuit works on the same principle, but the working state is relatively symmetrical, so Only the working mode of the positive half cycle of the AC current is described. When the current is negative half cycle, according to the symmetrical relationship, the working mode of the triple frequency current triangular wave inverter circuit can be obtained when the current is positive half cycle.

Specific Embodiment Nine: Referring to Figures 5, 10, 11, 12 and 13 to illustrate this embodiment, this embodiment is a further limitation of the harmonic suppression method described in Embodiment 7, triple frequency current triangular wave inverter circuit Using a full-bridge structure and using a bipolar control method,

When the bipolar control method is adopted, the triple frequency current triangular wave inverter circuit has four working modes in one cycle, starting from 0 time in the positive half cycle, and the two working modes of the positive half cycle are introduced in turn:

Section 0 to t ₁ : At time 0, the second and third switching tubes S ₂₃ and the second and second switching tubes S ₂₂ are turned on, and the secondary side voltage u _s of the balance reactor with secondary side and the voltage on the load are added to the second On the inductor L _2N , the current i _s of the second inductor L _2N increases positively, at this moment, the second inductor L _2N stores energy,

From t ₁ to t ₂ : At time t ₁ , the second and third switching tubes S ₂₃ and the second and second switching tubes S ₂₂ are turned off, and the current is of the second inductor L _{2N passes} through the second and first diode D ₂₁ Freewheeling with the second four diode D ₂₄ , the current i _s of the second inductance L _2N decreases linearly, at this time the second inductance L _2N and the secondary side voltage u _s of the balance reactor with secondary side supply power to the load together,

During the negative half cycle from Starting from the moment, the two working modes of the negative half cycle are introduced in sequence:

时刻，开通第二一开关管S₂₁和第二四开关管S₂₄，带副边的平衡电抗器的副边电压u_s和负载上的电压一起加在第二电感L_2N上，第二电感L_2N的电流i_s反向增加，此时第二电感L_2N储存能量， to t ₃ segment: in

At this time, the second first switch S ₂₁ and the second fourth switch S ₂₄ are turned on, the secondary side voltage u _s of the balance reactor with secondary side and the voltage on the load are applied to the second inductance L _2N together, and the second inductance The current i _s of L _2N increases in reverse, and at this time the second inductor L _2N stores energy,

From _t3 to _t4 : at time _t3 , turn off the second one switch _S21 and the second four switch _S24 switch, the current is of the second inductor _L2N passes through the second two diodes _D22 and The second and third diodes D ₂₃ freewheel, and the current i _s of the second inductance L _2N decreases linearly. At this time, the second inductance L _2N and the secondary voltage u _s of the balance reactor with secondary side supply power to the load together.

Claims (9)

1. the DC side harmonics of double reverse-stars type commutation system suppresses system, it is characterized in that: it comprises interphase reactor (1), frequency tripling electric current triangular wave inverter circuit (2), drive circuit (3), signal processing and control circuit (4), interphase reactor secondary current transducer (5), synchronous circuit (6) and load circuit current sensor (7) with secondary

Be connected in parallel on two groups of three phase half wave rectification bridge positive polarity output terminal (M of double reverse-stars type rectification circuit with the primary coil of the interphase reactor (1) of secondary, P) between, the positive polarity output terminal (P) that connects load power source with the centre tap of the primary coil of the interphase reactor (1) of secondary, be connected in parallel on the interchange input side of frequency tripling electric current triangular wave inverter circuit (2) with the secondary coil of the interphase reactor (1) of secondary, the DC side of frequency tripling electric current triangular wave inverter circuit (2) just, negative output terminal is connected N with the positive polarity output terminal (P) of load power source respectively with the negative polarity output) be connected

Synchronous circuit, (6) first signal input links to each other with the different name end of double reverse-stars type commutation system the first secondary coil, synchronous circuit, (6) secondary signal input links to each other with the different name end of double reverse-stars type commutation system the second secondary coil, synchronous circuit, (6) the 3rd signal input part links to each other with the different name end of double reverse-stars type commutation system the 3rd secondary coil, synchronous circuit, (6) output connects signal to be processed and control circuit, (4) synchronizing datum signal input

Load circuit current sensor (7) for detection of the positive polarity output terminal (P) of load power source with the electric current between the centre tap of the primary coil of the interphase reactor (1) of secondary, the current signal output end of load circuit current sensor (7) connects the load circuit current signal input of signal processing and control circuit (4)

Reactor secondary current transducer (5) is for detection of the electric current with the secondary coil of the interphase reactor (1) of secondary, the current signal output end of reactor secondary current transducer (5) connects the reactor secondary current signal input part of signal processing and control circuit (4)

The control signal output of signal processing and control circuit (4) connects the control signal input of drive circuit (3), and the driving signal output part of drive circuit (3) connects the driving signal input of frequency tripling electric current triangular wave inverter circuit (2).

2. the DC side harmonics of double reverse-stars type commutation system according to claim 1 suppresses system, it is characterized in that: described frequency tripling electric current triangular wave inverter circuit (2) adopts half-bridge or full bridge structure.

3. the DC side harmonics of double reverse-stars type commutation system according to claim 1 suppresses system, it is characterized in that: described frequency tripling electric current triangular wave inverter circuit (2) adopts full bridge structure, and frequency tripling electric current triangular wave inverter circuit (2) adopts unipolarity or ambipolar PWM control mode.

4. the DC side harmonics of double reverse-stars type commutation system according to claim 1 suppresses system, and it is characterized in that: described frequency tripling electric current triangular wave inverter circuit (2) is half-bridge structure, and circuit is by the first inductance (L _1N), the one one switching tube (S ₁₁), the one one diode (D ₁₁), the one one electric capacity (C ₁₁), the one one resistance (R ₁₁), the one or three switching tube (S ₁₃), the one or three diode (D ₁₃), the one or three electric capacity (C ₁₃), the one or three resistance (R ₁₃), the one or two electric capacity (C ₁₂), the one or two resistance (R ₁₂), the one or four electric capacity (C ₁₄) and the one or four resistance (R ₁₄) form the first inductance (L _1N) an end link to each other the first inductance (L with a end with the secondary coil of the interphase reactor 1 of secondary _1N) the other end simultaneously and the one one diode (D ₁₁) anode, the one one switching tube (S ₁₁) end, the one one resistance (R ₁₁) an end, the one or three switching tube (S ₁₃) an end, the one or three diode (D ₁₃) negative electrode, the one or three electric capacity (C ₁₃) an end link to each other the one one switching tube (S ₁₁) the other end simultaneously and the one one diode (D ₁₁) negative electrode, the one one electric capacity (C ₁₁) an end, the one or two electric capacity (C ₁₂) an end, the one or two resistance (R ₁₂) an end and the positive polarity output terminal (P) of load power source link to each other the one one resistance (R ₁₁) the other end and the one one electric capacity (C ₁₁) the other end link to each other, the negative polarity output (N) of load power source is simultaneously and the one or four resistance (R ₁₄) an end, the one or four electric capacity (C ₁₄) an end, the one or three resistance (R ₁₃) an end, the one or three diode (D ₁₃) anode and the one or three switching tube (S ₁₃) the other end link to each other the one or four resistance (R ₁₄) the other end simultaneously and the one or two resistance (R ₁₂) the other end, the one or four electric capacity (C ₁₄) the other end, the one or two electric capacity (C ₁₂) link to each other the one or three electric capacity (C with the other end with the secondary coil of the interphase reactor 1 of secondary ₁₃) the other end link to each other and the one or three resistance (R ₁₃) the other end link to each other.

5. the DC side harmonics of double reverse-stars type commutation system according to claim 1 suppresses system, and it is characterized in that: described full-bridge controlled rectification circuit is by the second inductance (L _2N), the 21 switching tube (S ₂₁), the 21 diode (D ₂₁), the 21 electric capacity (C ₂₁), the 21 resistance (R ₂₁), the two or three switching tube (S ₂₃), the two or three diode (D ₂₃), the two or three electric capacity (C ₂₃), the two or three resistance (R ₂₃), the two or two switching tube (S ₂₂), the two or two diode (D ₂₂), the two or two electric capacity (C ₂₂), the two or two resistance (R ₂₂), the two or four switching tube (S ₂₄), the two or four diode (D ₂₄), the two or four electric capacity (C ₂₄) and the two or four resistance (R ₂₄) form,

The second inductance (L _2N) an end link to each other the second inductance (L with a end with the secondary coil of the interphase reactor 1 of secondary _2N) the other end simultaneously and the 21 switching tube (S ₂₁) an end, the 21 diode (D ₂₁) anode, the 21 resistance (R ₂₁) an end, the two or three switching tube (S ₂₃) an end, the two or three diode (D ₂₃) negative electrode and the two or three electric capacity (C ₂₃) an end link to each other the 21 switching tube (S ₂₁) the other end simultaneously and the 21 diode (D ₂₁) negative electrode, the 21 electric capacity (C ₂₁) an end, the two or two switching tube (S ₂₂) an end, the two or two diode (D ₂₂) negative electrode, the two or two electric capacity (C ₂₂) an end and the positive polarity output terminal (P) of load power source link to each other the 21 electric capacity (C ₂₁) the other end and the 21 resistance (R ₂₁) the other end link to each other the two or two electric capacity (C ₂₂) the other end and the two or two resistance (R ₂₂) an end link to each other the two or two resistance (R ₂₂) the other end simultaneously and the two or two switching tube (S ₂₂) the other end, the two or two diode (D ₂₂) anode, with the other end, the two or the four switching tube (S of the secondary coil of the interphase reactor (1) of secondary ₂₄) an end, the two or four diode (D ₂₄) negative electrode, the two or four electric capacity (C ₂₄) an end link to each other the two or four electric capacity (C ₂₄) the other end and the two or four resistance (R ₂₄) an end link to each other the two or four resistance (R ₂₄) the other end simultaneously and the two or four switching tube (S ₂₄) the other end, the two or four diode (D ₂₄) anode, the negative polarity output (N) of load power source, the two or three switching tube (S ₂₃) the other end, the two or three diode (D ₂₃) anode, the two or three resistance (R ₂₃) an end link to each other the two or three resistance (R ₂₃) the other end and the two or three electric capacity (C ₂₃) the other end link to each other.

According to claim 5 or the DC side harmonics of 6 double reverse-stars type commutation systems suppress system, it is characterized in that: described switching tube is selected MOSFET or IGBT.

7. adopt the DC side harmonics inhibition system of double reverse-stars type commutation system claimed in claim 1 to realize the method that harmonic wave suppresses, it is characterized in that: described method is, load (8) is connected between the negative polarity output (N) of load power source of the positive polarity output terminal (P) of the load power source of double reverse-stars type commutation system and double reverse-stars type commutation system, synchronous circuit (6) gathers the line voltage signal of two anti-star transformer secondary, after filtering and signal processing, generate the benchmark triangular signal, this benchmark triangular signal is input in signal processing and the control circuit (4)

The load circuit current signal that signal is processed and control circuit (4) detects the benchmark triangular signal that receives and load circuit current sensor (7) the generation current reference signal that multiplies each other, the secondary current signal of this current reference signal and the interphase reactor with secondary (1) that detects relatively after, after the controller of signal processing and control circuit (4) is processed, produce PWM and drive signal, and this PWM driving signal is sent to drive circuit (3);

Drive circuit (3) drives signal with the PWM that receives to carry out exporting to frequency tripling electric current triangular wave inverter circuit (2) after the power amplification, the secondary current value of adjustment reactor (1), making the secondary current value of the interphase reactor (1) with secondary by current closed-loop control is 0.5 times of described load circuit current value, namely realizes the harmonic wave of double reverse-stars type commutation system is suppressed.

8. the method that suppresses of harmonic wave according to claim 7, it is characterized in that: frequency tripling electric current triangular wave inverter circuit adopts full bridge structure, and uses the unipolar control method,

When adopting the unipolar control method, frequency tripling electric current triangular wave inverter circuit has four kinds of mode of operations in half period, and the below is since 0 constantly, and four kinds of mode of operations of positive half period are followed successively by:

0 to t ₁Section: in 0 moment, open the two or three switching tube (S ₂₃), the two or three switching tube (S ₂₃) and the two or four diode (D ₂₄) together conducting, with the secondary voltage u of the interphase reactor of secondary _sBe added in the second inductance (L _2N) on, the second inductance (L _2N) current i _sForward flow, and the rising of starting from scratch, the second inductance (L _2N) storage power, this moment, the alternating current-direct current side did not have the exchange of energy,

t ₁To t ₂Section: at t ₁Constantly, open the two or two switching tube (S ₂₂), this moment the two or three switching tube (S ₂₃) and the two or two switching tube (S ₂₂) together conducting, with the secondary voltage u of the interphase reactor of secondary _sBe added in together the second inductance (L with the voltage in the load _2N) on, the second inductance (L _2N) current i _sRise rapidly the second inductance (L _2N) continue storage power, this moment, the alternating current-direct current side was all exported energy to the second inductive energy storage,

t ₂To t ₃Section: at t ₂Constantly, turn-off the two or three switching tube (S ₂₃), the 21 diode (D ₂₁) afterflow, at this moment the two or two switching tube (S ₂₂) and the 21 diode (D ₂₁) together conducting, with the secondary voltage u of the interphase reactor of secondary _sBe added in the second inductance (L _2N) on, the second inductance (L _2N) current i _sContinue to rise the second inductance (L _2N) continue storage power, this moment, the alternating current-direct current side did not have the exchange of energy,

t ₃To t ₄Section: at t ₃Constantly, turn-off the two or two switching tube (S ₂₂), the 242 closes pipe (D ₂₄) conducting, close pipe (D this moment the 242 ₂₄) and the 212 pass pipe (D ₂₁) together conducting, with the secondary voltage (u of the interphase reactor of secondary _s) and inductance power to the load the second inductance (L _1N) current i _sBegin to descend the second inductance (L _1N) continue storage power, this moment, the energy of AC and inductance passed to load.

9. the method that suppresses of harmonic wave according to claim 7, it is characterized in that: frequency tripling electric current triangular wave inverter circuit adopts full bridge structure, and uses ambipolar control method,

When adopting ambipolar control method, frequency tripling electric current triangular wave inverter circuit has four kinds of mode of operations in one-period,, since 0 constantly 2 kinds of mode of operations of positive half period is followed successively by at positive half period:

0 to t ₁Section: in 0 moment, open the two or three switching tube (S ₂₃) and the two or two switching tube (S ₂₂), with the secondary voltage u of the interphase reactor of secondary _sBe added in together the second inductance (L with the voltage in the load _2N) on, the second inductance (L _2N) current i _sForward increases, at this moment the second inductance (L _2N) storage power,

t ₁To t ₂Section: at t ₁Constantly, turn-off the two or three switching tube (S ₂₃) and the two or two switching tube (S ₂₂) switching tube, the second inductance (L _2N) current i _sThrough the 21 diode (D ₂₁) and the two or four diode (D ₂₄) afterflow, the second inductance (L _2N) current i _sLinear decline, at this moment the second inductance (L _2N) and with the secondary voltage u of the interphase reactor of secondary _sPower to the load together,

Negative half-cycle from

Constantly begin, 2 kinds of mode of operations of negative half-cycle be followed successively by:

To t ₃Section:

Constantly, open the 21 switching tube (S ₂₁) and the two or four switching tube (S ₂₄), with the secondary voltage u of the interphase reactor of secondary _sBe added in together the second inductance (L with the voltage in the load _2N) on, the second inductance (L _2N) current i _sOppositely increase, at this moment the second inductance (L _2N) storage power,

t ₃To t ₄Section: at t ₃Constantly, turn-off the 21 switching tube (S ₂₁) and the two or four switching tube (S ₂₄) switching tube, the second inductance (L _2N) current i _sThrough the two or two diode (D ₂₂) and the two or three diode (D ₂₃) afterflow, the second inductance (L _2N) current i _sLinear decline, at this moment the second inductance (L _2N) and with the secondary voltage u of the interphase reactor of secondary _sPower to the load together.

Images