Resonance power amplifier

FIELD: electricity.

SUBSTANCE: resonance power amplifier contains an input transformer, n amplifying cascades from n step-down power transformers interconnected by means of n in-series resonance circuits where n=2, 3, …, m, and a feedback device providing unidirectional motion of electric energy from the secondary winding of the last power transformer to the primary winding of the input transformer.

EFFECT: improvement in amplification coefficient of the resonant converter up to 2-10 and stabilisation of amplification coefficient at load and frequency change.

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The invention relates to electrical engineering, in particular to resonant converters of electrical energy on the basis of the resonance amplifiers.

Known resonant power amplifier frequency containing the serially connected primary winding of the power transformer, the windings of the two counter enabled managed magnetic reactors, tanks and the secondary winding of the input step-down transformer, which form a series resonant circuit. The resonant capacitance connected between a terminal of the secondary winding of the input transformer and the primary winding of the power transformer. Controlled magnetic reactors included between two other terminal of the secondary winding of the input transformer and the primary winding of the power transformer. Two counter enabled managed magnetic reactor functions inductive feedback to stabilize the voltage when the electric load. The primary winding of the input transformer is connected to a source of electrical energy. Electrical load connected to the secondary winding of the power transformer. The gain depends on the load and configuration of the resonant circuit exceeds unity (Elementary physics / Ed. by Acad. Gstandard. VOL. Colemani is, waves, optics, atomic structure. - M., 1975, p.81-82).

The disadvantage of the Converter is high enough gain and the complexity of the amplifier is set at the resonant frequency under varying electrical load.

The task of the invention is to increase the gain and reduce the dependence of the parameters of the inverter from load and frequency.

The technical result is to increase the gain of the resonant Converter to 2-10 and stabilize the value of the gain when the load changes and frequency.

The technical result is achieved by the resonant power amplifier containing the input and power transformers with load in the secondary winding of the power transformer and a serial resonant circuit between the transformer consisting of a capacitance C and inductance of the input winding of the power transformer, and a feedback connection between the input windings and a power transformer, a resonant amplifier contains the n amplifier stages of the n step-down transformers connected using n consecutive resonant circuits, where n=2, 3, ...m, and feedback made in the form of devices that provide unidirectional movement electr the cooling energy from the secondary winding of the last of the power transformer to the primary winding of the input transformer, the capacity of each subsequent n-th power transformer is associated with the capacity of the previous n-1-th power transformer ratio: P_n=cu_n-1where the gain of one stage.

In the embodiment, the resonance amplifier, the feedback device in the form of uninterruptible power supply, an input connected to a secondary winding of the last of the power transformer, and the output from the primary winding of the input transformer.

In another embodiment, the resonant amplifier, the feedback device made in the form of unidirectional inductance, the input of which is connected to a secondary winding of the last of the power transformer, and the output from the primary winding of the input transformer.

The invention is illustrated in figures 1, 2, where figure 1 shows the electric circuit of the resonant Converter of two stages with a feedback device in the form of an uninterruptible power supply, figure 2 - electrical circuit of the resonant Converter of two stages with a feedback device in the form of one-way inductive coupling.

Resonant power amplifier 1 includes an input transformer with 1 primary 2 and secondary windings 3, the first power transformer with 4 primary 5 and secondary windings 6 and WTO is Oh power transformer 7 with the primary 8 and secondary windings 9. The secondary winding 3 of the input transformer 1 is connected with the primary winding 5 of the first power transformer 4 through the condenser 10 with capacity₁. The capacity C₁and the inductance L₁the primary winding 5 of the power transformer 4 form a first resonant circuit 11 of the first amplification stage is configured to frequencyequal to the frequency of the supply network 12 connected to the primary winding 2 of the input transformer 1.

The second amplification stage is made of the primary winding 8 with an inductance of L₂a second power transformer 7 which is connected with the secondary winding 6 of the first power transformer 4 through the condenser 13 with capacity₂. Capacity₂and the inductance L₂form a second serial resonant circuit with the resonant frequencyequal to the frequency of the supply network 12 and the resonant frequency of the first resonant circuit 11. The feedback device 14 is in the form of uninterruptible power supply unit 15 containing a rectifier 16, a battery 17 and an inverter 18 with a frequency f₀and the output voltage equal to the frequency and the voltage of power supply 12. The secondary winding 9 of the second power transformer 7 is connected to the load 19 and to the input of the rectifier 16 feedback device 14.

Resonant power amplifier is in figure 2 contains one input transformer 1, the first 4 and the second 7 power transformers, United resonant circuits similar to the circuit diagram of a resonant power amplifier figure 1. The feedback device 20 made in the form of unidirectional inductance 21, comprising three windings 22, 23 and 24. The windings 22 and 23 are connected to the counter and positioned on the magnetic core. The winding 24 is located between the windings 22 and 23 (Weimou. Unilateral inductive link // Inventor and innovator, 2012, No.1, p.30-31). The input winding 22 is connected with the secondary winding 9 of the second power transformer 7. The output winding 24 unidirectional inductance 21 is connected with the primary winding 2 of the input transformer 1. When a voltage is applied to the counter is enabled windings 22 and 23 of the magnetic field of these coils excites EMF in the winding 24 and is transmitted electrical energy from the amplifier output power to its input. When voltage is applied to the coil 24 in the windings 22 and 23 occurs EMF, opposite in sign, the voltage at the output of these windings is zero and the electric power transmission from the input of the amplifier to the output of the amplifier does not occur.

Resonant power amplifier operates as follows.

In a resonant circuit EMF capacity and the EMF of self-induction coil inductance in Q times greater than the external voltage generator, attached to the same chain, where- q circuit, X_Land R - inductive and resistance of the circuit. Usually Q=10-100. If the reactance of the resonant circuit is inductive resistance of the low-voltage winding of the transformer is increased to Q times the external voltage generator increases n times the output of the transformer, wherethe transformation ratio, W₁, W₂the windings of the transformer EMF of self-induction and mutual induction electromotive force in the inductive impedance of the transformer lags behind the current by a quarter period or at 90°.

The electrical energy supply network 12 is supplied to the primary winding 2 of the input step-down transformer 1 increases current decreases the voltage in the secondary winding 3 in accordance with the transformation ratio input transformer 1. In the serial resonance circuit 11, the electrical energy increases the voltage in the Q₁again, wherethe first factor of the resonant circuit 11 L₁C₁, R₁and X_L- active and inductive resistance of the first resonant circuit 11. Electric energy with increased current and voltage supplied to the primary winding 5 of the first step-down power transformer 4 increases current and the mind is leetse voltage in the secondary winding 6 of the first power transformer 4 in accordance with the transformation ratio of the first power transformer 4. In the serial resonant circuit L₂With₂electrical energy increases the voltage in the Q₂again, where- the second factor of the resonant circuit L₂C₂, R₂and X_L- active and inductive resistance of the second resonant circuit. Electric energy with increased voltage reduces the voltage and increases the current in the secondary winding 9 of the second power transformer 7 and supplied to the electrical load 19. Part of the electrical energy from the secondary winding 9 of the second power transformer 7 is supplied to the rectifier 16 feedback device 14, charges the battery 17 through the inverter 18 is supplied to the primary winding 2 of the input transformer 1.

Electric power at the inverter input power:

P_I=V_I·I_I,

where I_IV_I- current and voltage of power supply 12.

Electric power at the input of the first power transformer 4:

P₁=I_I-V_I-Q₁=K₁·P_I,

where K₁a gain of the first stage, K₁=Q₁.

Electric power amplifier output:

P_o=Q₁·Q₂·I_I·V_I=K₁·₂-R_I,

where K₂the gain of the second cast is Yes, to₂=Q₂.

Examples of the resonance amplifier.

Example 1. The input transformer 1 (Fig 1) is designed as a transformer with an input voltage of 220 V, 50 Hz, 1 kW. The first power transformer 4 380/220 V has an electric power of 2 kW, a second power transformer 7 380/220 V is the electric power of 6 kW. Tuning of the resonant mode is produced by the selection of the capacitors 10 and 13 at the level of 10-100 μf. The first resonant circuit 11 and the second resonant circuit to have a resonant frequency of 50 Hz. The gain of the first stage is equal to₁=2, the second cascade to the₂=2,7. Overall gain K=K₁·₂=5,4. The output voltage of the amplifier is 220 V, the output power of 5.4 kW.

The feedback device 14 is in the form of uninterruptible power supply unit 15, the input of which is connected to the secondary winding 9 of the second power transformer 7, and the output of the power supply unit 15 is connected with the conclusions of the primary input winding 2 of the transformer 1.

Example 2. The input transformer 1 (figure 2) is made in the form of a transformer with an input voltage of 450 V and a frequency of 10 kHz, the electric power of 7.5 kW. Electric network 12 with a voltage of 400 V and a frequency of 10 kHz is fed from the frequency Converter (figure 2 h is shown). The first step-down power transformer 1 with a voltage 450/220, the frequency of 10 kHz has an electric power of 4 kW, the second step-down power transformer 7 voltage 450/220, the frequency of 10 kHz has a electrical capacity of 7.5 kW. The setting at the resonant frequency produced by the selection of the capacitors 10 and 13 and the change of the frequency. The first and the second resonant circuit to have a resonant frequency of 10 kHz. The gain of the first stage of the first power transformer and the resonant circuit 11 is equal to₁=2.5, the second cascade with a second power transformer - K₂=2,5. Overall gain K=6,25. The output voltage of the amplifier is 220 V, the output power of 6.5 kW.

The feedback device 20 made in the form of unidirectional inductance 21, providing one-sided the inductive coupling between the output and the input of the power amplifier. Two counter enabled input windings 22 and 23 are connected with the secondary winding 9 of the second power transformer 7. The output winding 24 is connected with the primary winding 2 of the input transformer 1.

The designed amplifier has the following advantages. Unlike the prototype, the feedback device 14 and 20 transferred from the resonant circuit to an external circuit, which improves the resonant tuning circuits and increases the quality factor Q and efficient gain K. Using multiple resonant circuits, transformers and amplifier stages, the number of which is n=2, 3, ...m, increases the gain and conversion of electrical energy. Increasing the resonance frequency reduces the mass of the power amplifier and simplifies the configuration of the resonant mode by frequency control network 12. Resonant amplifiers allow you to reduce the load on the distribution network when using stationary and mobile power plants.

1. Resonant power amplifier containing the input and power transformers with load in the secondary winding of the power transformer and a serial resonant circuit between the transformer consisting of a capacitance C and inductance of the input winding of the power transformer, and a feedback connection between the input windings and the power transformer, characterized in that the resonant amplifier contains the n amplifier stages of the n step-down transformers connected using n consecutive resonant circuits, where n=2, 3, ...m, and feedback made in the form of devices that provide unidirectional movement of electric power from the secondary winding the last of the power transformer to the primary winding of the input transformer, the power is here each subsequent n-th power transformer is associated with the capacity of the previous n-1-th power transformer ratio: P _n=cu_n-1where the gain of one stage.

2. The resonant amplifier according to claim 1, characterized in that the feedback device is made in the form of uninterruptible power supply, an input connected to a secondary winding of the last of the power transformer, and the output from the primary winding of the input transformer.

3. The resonant amplifier according to claim 1, characterized in that the feedback device made in the form of unidirectional inductance, the input of which is connected to a secondary winding of the last of the power transformer, and the output from the primary winding of the input transformer.