JPH0611200B2 - AC / DC power supply device for reluctance generator - Google Patents

Description

The present invention relates to an AC / DC power supply device for a reluctance generator.

(Prior Art) During a traffic period such as an automobile or a ship where power cannot be supplied from the outside, the size of power equipment including a prime mover is small,
Weight reduction is required.

To meet the demand for smaller and lighter power equipment,
Ultra-high-speed generators of tens of thousands rpm to hundreds of thousands of rpm have been developed.However, in ultra-high-speed generators, if a synchronous generator is used, the centrifugal force between the rotor and the field current supply source will be increased due to the strong centrifugal force. There arises a problem that the brush provided in the above may be damaged.

In addition, when an induction generator is used, especially when it has a squirrel-cage rotor suitable for high speed rotation, the secondary conductor and the short-circuit ring are made of cast aluminum, so that the There has been a problem that the conductor is separated from the short-circuit ring and the iron core, and eventually the rotor is destroyed.

On the other hand, the reluctance generator is the ultimate synchronous generator with the field windings removed, and instead of exciting the field windings, a phase-advancing current is passed through the armature windings to cause armature reaction. It operates as a synchronous generator by utilizing the magnetizing effect of. Therefore, the structure of the rotor is simplified and the generator can be said to be suitable as an ultra-high speed generator.

Next, the characteristics of the reluctance generator will be described. FIG. 4 is a vector diagram of a general ultimate synchronous generator.

However, Ia: Armature current Id: Straight axis of armature current (straight axis current) Iq: Horizontal axis of armature current (horizontal axis current) Xd: Direct axis reactance Xq: Horizontal axis reactance r: Winding resistance Da: Armature voltage Eo: Induced electromotive force due to field current Since the reluctance generator is a synchronous generator with the field winding removed, the induced electromotive force due to field current Eo
Is set to 0 and the armature current Ia is advanced with respect to Ea, the fifth
The vector diagram of the figure is obtained.

From this vector diagram, Ia ・ cosθ ＝ Iq …… (1) Is ・ sinθ ＝ Id …… (2) Va ・ cosδ ＝ Xd ・ Id …… (3) Va ・ sinδ ＝ Xq ・ Iq …… (4) And the effective output P of the reluctance generator is Becomes

Here, on the output side of the reluctance generator, a lagging phase current source (absorption source of a phase advancing current) capable of supplying a required exciting current regardless of a load is required. Therefore, the output side of the reluctance generator can be generally represented as shown in FIG. Power consumption at load RL 'at this time P = 3V ² / R
Since L'is equal to the effective output of equation (5), the armature voltage
The following equation holds regardless of Va.

That is, if the horizontal axis reactance Xq and the direct axis reactance Xd are determined, the phase angle δ is determined by the load resistance RL ′, Then RL 'is the minimum value, and therefore the equivalent load resistance at maximum output is determined. here, By substituting in (5) and rearranging, the maximum effective output Is obtained. Therefore, the direct-axis reactance Xd is large, and The smaller is, the larger the maximum effective output can be.

FIG. 7 shows an example of a rotor used in a reluctance generator, which has a substantially I-shaped configuration with a large direct-axis reactance Xd and a ratio of the horizontal-axis reactance Xq to the direct-axis reactance. Is small. That is, when the direction of the rotor rotation position and the coil axis coincide with each other as shown in FIG. 8 (a), the magnetic flux generated by the coil passes through the solid arrow, so that the magnetic resistance of the magnetic path is small, and therefore the self-inductance L _{1 of the} coil is small. Grows larger. When the rotational position of the rotor and the coil axis are orthogonal to each other as shown in FIG. 8 (b), the magnetic resistance of the magnetic path is large and the inductance of the coil is small. Than this,
It is desirable that the shape of the rotor be such that the magnetic resistance is small in the d-axis direction and large in the q-axis direction as shown in FIG.

(Problems of the prior art) In such a reluctance generator, a phase advancing capacitor has been conventionally used as a method for supplying a phase advancing current.
There is a problem that the capacity of the capacitor becomes large and that the capacity of the capacitor is sufficiently controlled for a variable rotation speed and a variable load. Moreover, in this type of reluctance generator, no effective means has been taken to supply the generator load heavy current to both the DC load and the AC load at the same time.

(Object of the present invention) An object of the present invention is to connect a voltage source inverter to a load circuit of a reluctance generator and detect the rotational position of the rotor and the load current to control the inverter to control the armature current. To provide an AC / DC power supply device for a reluctance generator, which is capable of advancing 90 degrees with respect to no-load electromotive force and at the same time can supply the generator load current to both DC load and AC load. Especially.

(Summary of the Invention) An alternating / direct power supply device for a reluctance generator according to the present invention is
In a reluctance generator including a substantially I-shaped rotor having a small magnetic resistance in one direction orthogonal to the rotation axis and a large magnetic resistance in the direction orthogonal to this direction, the relative position of the rotor and the stator is The signal from the position detector to detect and the generator load current detector calculates the direct current of the load current,
Based on the obtained direct-axis current, the voltage source inverter connected to the output side of the generator is energized at a predetermined delay position angle with respect to the no-load induced electromotive voltage, and no-load induction is performed according to the rotor position. Control is performed so that an armature current having a 90-degree phase advance with respect to the electromotive voltage is supplied, and an AC load circuit is connected in parallel to the voltage source inverter at the output end of the reluctance generator via a switching switch. It is a feature.

Example An example of the present invention will be described below with reference to the drawings. First
FIG. 1 is a schematic block diagram of a reluctance generator control device of the present invention. In the figure, a reluctance generator 2 having a rotor having a substantially I-shape as shown in FIG.
Is driven by a prime mover 1 such as a turbine. The relative position between the rotor of the reluctance generator and the stator winding is detected by the position detector 3 and input to the pulse shaping circuit.
The position signal shaped by the pulse shaping circuit is sent through the logic circuit 5 to output signals Pu, Pv, Pw to the direct axis current detection circuit 8. The other output signal of the logic circuit 5 is a triangular wave generation circuit.
12 and the inverter drive signal generator 14. Also,
On the output side of the reluctance generator, current transformers CTu6, CTw6 ′
Is provided to detect the U-phase and W-phase generator output currents. The output currents of the current transformers 6 and 6'are input to the current amplification calculation circuit 7 and the V-phase output current Iv is calculated by v = (u + w) (8). The output signal of the current amplification calculation circuit 7 is sent to the direct-axis current detection circuit 8, and the direct-axis current Id in the output current is obtained from the output signals Pu, Pv, Pw of the logic circuit 5,
The error amplification circuit 9 obtains an error from the reference value Ido of the direct current set by the direct current reference generator 10, and sends an error signal to the comparison circuit 13. In the comparison circuit 13, the inverter drive signal is generated from the output signal of the triangular wave generation circuit 12 and the error signal of the direct axis current so that the phase angle between the no-load induced electromotive force and the armature voltage in the vector diagram of FIG. 4 becomes δ. It energizes the device 14 and drives the voltage source inverter 15.

On the output side of the voltage source inverter, a hand-sliding capacitor C ₀ ,
The diode D, the switch S ₁ , the starting circuit 16 including the DC power supply E _s, and the load RL are connected. Also, on the output side of the generator, an AC load is applied via the changeover switch 17 and the control device 18.
Connect 19

FIG. 2 is an example of a circuit diagram for detecting the direct-axis current Id included in the output current of the reluctance generator. U-phase and W-phase generator output currents detected by the current transformers 6 and 6 ',
That is, the load current is input to the operational amplifiers OP ₁ and OP ₂ of the current amplification arithmetic circuit 7, and the outputs of OP ₁ and OP ₂ are inverted and added by the operational amplifier OP ₃ , that is, V is calculated by the equation (8). Find the output power of the phase. The generator output current of each phase is the analog switch S of the direct-axis current detection circuit 8.
It is added by the operational amplifier OP ₄ through w ₁ , Sw ₂ , and Sw ₃ , and only the DC component, that is, the direct-axis current Id is taken out from the low-pass filter. The analog switch is the output of the logic circuit
It is configured to turn on when Pu, Pv, and Pw are 1. Therefore, the load currents Iu, Iv, and Iw of each phase are
When in-phase with u, ev, and ew, the direct-axis current Id becomes 0,
Further, when the load current of each phase includes a forward current of 90 degrees with respect to the phase voltage, the direct axis current Id is proportional to the 90-degree advance component.

Now, in the steady state, the fundamental wave component I of the load current of each phase I
Of u ₁₁ , Iv _{1, and} Iw ₁ , the amplitude of each phase voltage and the in-phase component is I ₁ q, the advance of the 90-degree phase advance component is I ₁ q, and the advance of the 90-degree phase component is I ₁ d. Then, the following equation is established.

Also, the fundamental wave components of the super power components P ₁₁ , P ₂₁ , and P ₃₁ are Becomes The direct-axis current Id is a direct current component of Id = Iu ₁ · P ₁₁ + Iv ₁ · P ₂₁ + Iw ₁ · P ₃₁ (11), so the equations (9) and (10) are substituted, Can be asked as

FIG. 3 is a characteristic diagram of the reluctance generator control device of the present invention. The no-load induced electromotive forces eu, ev, and ew of each phase are represented as shown in FIG. FIG. 3B shows an output waveform of the position detector 3, which generates an instantaneous pulse as shown at the zero point of each phase voltage and the maximum positive and negative values. FIG. 3C shows an output waveform of the pulse shaping circuit 4, which shapes the pulse generated at the zero point of each phase voltage of the position detector. FIG. 3 (d) shows
Output signal of logic circuit 5 for each phase A signal having a pulse width of is obtained. FIG. 3 (f) shows
In the description of the characteristic for setting the output signal δ (phase angle in FIG. 5) of the comparison circuit 13, the direct axis current Id obtained in FIG. 2 and the reference value Id set in the direct axis current reference generator 10 are set. ₀ and the level of the error signal Id _e obtained by comparing, obtain the intersection of the triangular wave formed by the triangular wave generating circuit 12, whereby the phase angle δ
Ask for. FIG. 3 (g) shows an inverter drive signal generator.
With the waveform of the signal Put for driving the voltage source inverter 15 from 14, the voltage source inverter is driven by the signal Put to control the armature current that is advanced by 90 degrees with respect to the no-load induced electromotive voltage.

Next, operation control of the reluctance generator will be described. The reluctance generator is driven by the prime mover 1, the switch S ₁ of the starting circuit 16 is turned on, the DC power supply Es is energized, and the reluctance generator is initially excited via the inverter 15. When the terminal voltage of the reluctance generator is established and becomes equal to or higher than the power supply voltage Es, the diode D of the starting circuit is reverse-biased, the switch S ₁ is turned off to disconnect the power supply Es from the inverter, and the DC power is supplied to the load RL. Further, the changeover switch 17 is turned on as necessary to supply electric power to the AC load. The relative position of the rotor and the stator of the reluctance generator is detected by the position detector 3, and
The output current of the generator is detected by the current transformer 6, and the direct current
Id is calculated and a pulse having a δ delay phase with respect to the no-load electromotive force is supplied to the voltage source inverter to control the load current of each phase, that is, the 90-degree advanced current of the electric machine current.

(Effects of the Invention) As described above, the present invention relates to a reluctance generator having a substantially I-shaped rotor, including a position detector for detecting the relative position of the rotor and the stator, and a load current detector. The direct-axis current is calculated from the signal, and the voltage source inverter is energized with a predetermined delay phase angle with respect to the no-load induced electromotive voltage.
Since the armature current of the advanced phase is controlled to flow, the advanced phase current can be controlled stably even if load change occurs by turning on the changeover switch to supply power to the AC load. You can Further, by turning on the changeover switch, it is possible to supply a part of the generator output to the AC load at the same time and supply power to both the DC load and the AC load at the same time.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of the present invention, FIG. 2 is a direct-axis current detection circuit, FIG. 3 is a characteristic diagram, FIGS. 4 and 5 are vector diagrams, and FIG. 6 is a load of a reluctance generator. Circuit, FIG. 7 is a configuration diagram of the rotor, and FIG. 8 is an explanatory diagram. 1 ... motor, 2 ... reluctance generator, 3 ... position detector, 4 ... pulse shaping circuit, 5 ... logic circuit, 6,
6 '... current transformer, 7 ... current amplification arithmetic circuit, 8 ... direct axis current detection circuit, 9 ... error amplification circuit, 13 ... comparison circuit,
14 …… Inverter drive signal generator, 15 …… Voltage type inverter, 16 …… Starting circuit, 17 …… Changeover switch, 18 …… Control device, 19 …… AC load.

Claims (1)

[Claims] 1. A reluctance generator having a substantially I-shaped rotor having a small magnetic resistance in one direction orthogonal to the rotation axis and a large magnetic resistance in the direction orthogonal to this direction. A position detector for detecting the relative position of
The signal from the generator load current detector is used to calculate the direct-axis current of the load current, and based on the obtained direct-axis current, it is applied to the generator output side with a predetermined delay phase angle relative to the no-load induced electromotive voltage. The connected voltage source inverter is energized to control the armature current of 90-degree phase advance with respect to the no-load induced electromotive force according to the rotor position, and the voltage is applied at the output end of the reluctance generator. An AC / DC power supply device for a reluctance generator, characterized in that an AC load circuit is connected in parallel to a type inverter via a changeover switch.