WO2014157719A1

WO2014157719A1 - High-efficiency output stabilization power generation device and small water-flow type hydraulic power generation system

Info

Publication number: WO2014157719A1
Application number: PCT/JP2014/059464
Authority: WO
Inventors: 原嶋　崇; 勉上石
Original assignee: 中央電子システム株式会社; エスケー・テック販売株式会社; 八洲電機株式会社
Priority date: 2013-03-29
Filing date: 2014-03-31
Publication date: 2014-10-02

Abstract

A power generation device (10) is constituted by a permanent magnet type power generator (20), a control circuit (30), and an addition connection section (38), and applies an output voltage to a load (12). The permanent magnet type power generator (20) is a three-phase AC generator. Each output winding for the U-phase, V-phase, and W-phase has the number of windings reduced by half so that the output voltage is half of a rated voltage, and is constituted by mutually parallel two-system output windings (24U₁ and 24U₂, 24V₁ and 24V₂, and 24W₁ and 24W₂). The output voltages in the two-system output windings are rectified in the control circuit (30) for each U-phase, V-phase, and W-phase with each system maintained independently; stabilized by step-down DC to DC convertors (34-1, 34-2) for each system; serially added through the addition connection section (38); and then applied to the load (12).

Description

High-efficiency output-stabilized power generator and flowing water type small hydropower system

The present invention relates to a high-efficiency output-stabilized power generation device using a permanent magnet and a flowing water type small hydropower generation system.

Since permanent magnet generators use permanent magnets for the rotor, they can efficiently generate generated power and are used as wind power generators, micro hydropower generators, and on-vehicle generators.

In a permanent magnet type generator, the rotational speed of the generator and the generated voltage are in a proportional relationship. However, the generator as described above is usually designed to obtain rated power at low speed rotation, and the wind power is strong. However, there is a problem that the generated voltage exceeds the maximum input voltage (withstand voltage) of the controller when the water flow rate is high, or when the vehicle operates at high speed or during no-load operation. It was.

Fig. 11 shows the output drooping characteristics of a permanent magnet generator and the load fluctuation characteristics of hydraulic power and wind power. In FIG. 11, point A is no-load operation, point B is the rated load (5.5A) droop point, point C is the rotation of the turbine or windmill due to the increase in generator torque due to the current flowing, It shows the point where the voltage drops.

The voltage at this point C is 100 VAC (phase voltage). From this point, in the case of no-load operation, the rotation / voltage suddenly increases and reaches about 300 VAC (phase voltage). At this time, the rectified output voltage becomes a high voltage of about 720 VDC. Therefore, conventionally, for example, a predetermined idle current is passed to prevent a large voltage change from occurring even when there is no load. That is, it always involves a large power loss.

Also, in order to make the voltage fluctuation accompanying the fluctuation of the generator rotation constant, it is necessary to lower the generated voltage at high speed and increase the generated voltage at low speed, and adjust the voltage with a buck-boost converter. In this case, a booster circuit and a step-down circuit must be used, and there is a problem that the device becomes complicated and expensive.

In contrast to the above, for example, in Patent Document 1, the output winding, output side solenoid coil, output terminal, and tip of the control solenoid coil in a three-phase AC generator are connected to a three-phase rectifier, and power is supplied to the DC terminal of the three-phase rectifier. By connecting a voltage control switch such as a transistor, detecting the voltage of the load three-phase rectification unit, and controlling the on-time of the voltage control switch so that the voltage becomes constant, the device can be simplified. In addition, a permanent magnet generator voltage stabilization control device has been proposed in which the capacity of the power transistor is reduced.

As shown in FIG. 12, the permanent magnet generator 1 described in Patent Document 1 has coils L1 and L2 arranged in series with respect to the generator coil 2 in order to control the output voltage at no load. Forcibly flowing i1 through the generator and adopting the AC constant voltage method using the output voltage drooping characteristic of the generator and the voltage drop of L1, the coil L1, There is a problem that a large heat loss occurs in order to consume the stored energy of the counter electromotive force due to L2. Further, this Patent Document 1 proposes a winding switching method that reduces the output winding to 1/2 or less when the rotation speed is high. In addition, there is a problem that an electronic circuit for switching windings is required, and a control algorithm is also complicated, leading to an increase in manufacturing cost.

Conventionally, as a method for obtaining a low-speed high voltage in a permanent magnet system, an 84-slot, 56-pole outer rotor system has been proposed, but there is a problem that the rotational torque is large (Patent Document 2). . Similarly, the coreless type has been proposed for the multi-pole system, but there is a problem in power generation efficiency.

For example, in a flowing-water hydroelectric generator, the water turbine continues to rotate regardless of the state of the power receiving side, so that it operates at maximum rotation and maximum voltage without load even before the control circuit is activated. In this state, if the input voltage exceeds the withstand voltage of the control circuit or the grid interconnection device, and the power generation output is connected as it is, these will be broken.

For this reason, conventionally, a large current was passed through the dummy resistor before starting, causing the turbine to rotate and the generation voltage drop, and then starting up the grid interconnection device.

This method has the disadvantage that the startup and re-startup procedures are difficult, and the dummy resistor generates heat and consumes a large amount of power, reducing the overall power generation efficiency.

In the case of a small hydroelectric generator, it can be installed in an agricultural waterway or the like and connected to a power system, and a minimum number of revolutions of 1000 rpm or more is required to obtain a predetermined power. For this purpose, a running water drop of 1 m or more and a flow rate of 1 m ³ or more are necessary, and the installable water channels are limited.

Furthermore, when a generator that is always driven by an engine, such as a refrigerator, is installed, there is a voltage drop that uses a shunt circuit for high voltage that exceeds the withstand voltage of the control circuit. However, the amount of heat generated by the shunt circuit is large, which is impractical.

For example, an always-driven generator has an engine speed of about 600 rpm and a speed increase ratio of 2.5 times, and a rectified output of about 300 VDC is obtained at a generator speed of 1500 rpm. × 2.5), the generated voltage is 300 V × 10000 / 1500≈2000 VDC, which exceeds the withstand voltage 1200 V of the semiconductor constituting the control circuit.

In addition, when two generators are driven in conjunction with a pair of left and right wheels, the generated voltage differs in situations where the rotation speeds of the left and right wheels are different, and the high voltage battery cannot be charged simply by adding. is there.

The invention described in Patent Document 3 relates to a power converter, and the configuration thereof is, in particular, from the circuit configuration diagram shown in FIG. 7, DC power sources 21 and 22 connected in parallel to the AC power source 10, and a DC power source 21. The power converter 4 is connected to the power source 3 and the power converter 3 is connected to the DC power source 22. The outputs of the two power converters 4 and 3 are supplied in series to the load 5.

Here, the DC power source 21 includes a transformer 21a connected to the AC power source 10 and an AC-DC converter 21b to which a current after the transformation of the transformer 21a is input. The DC power source 22 is similarly transformed. And an AC-DC converter 22b.

Further, in the circuit configuration shown in FIG. 7 of Patent Document 3, the transformers 21a and 22a are interposed between the AC power source 10 and the AC-DC converters 21b and 22b, and the power from the AC power source 10 is the transformer 21a, Since the AC power supply 10 and the AC-DC converters 21b and 22b are not directly connected to each other, the weight of the apparatus is increased, and a transformer loss occurs in the transformers 21a and 22a. There is a problem that efficiency is lowered.

In the circuit configuration shown in FIG. 4 of Patent Document 4, the switching rectifier circuit as a control circuit is an integrated configuration, and the output voltages of the parallel coils W2 and W3 indicated by reference numeral 406 in FIG. 4 are added. It is the structure which flows into a switching rectifier circuit. That is, for the control circuit, the output voltage is already added at the input stage, and the semiconductors constituting the control circuit of the subsequent stage, for example, S704, S732, S706, and S734 in FIG. The two output voltages from are added and applied.

Further, the power source 210 of the AC generator 205 in FIG. 2 is an internal combustion engine or a turbine, and is mainly a portable generator, and the rotational speed thereof is appropriately controlled by the controller 204. It has become.

However, in the case of a rotary drive source consisting of a windmill, a water turbine, or an automobile's rotating shaft, the output voltage fluctuates greatly depending on the rotational speed, and if a permanent magnet generator is used, the output during high-speed rotation When the voltage is applied to the semiconductor of FIG. 7, these semiconductors may be broken down by an excessive voltage.

In order to avoid breakdown of the control circuit semiconductor as described above, there is a method in which a shunt circuit is provided at the output of the generator and a current is passed through the shunt circuit when the voltage is high to reduce the voltage. Moreover, although it is very expensive, a method for increasing the breakdown voltage of the semiconductor is employed, but there is a limit.

In the circuit configuration shown in FIG. 1 of Patent Document 5, a plurality of sets (two sets) of output windings are connected in series or in parallel to one inverter circuit 7 through rectifiers. Are rectified individually and connected in series or in parallel, and connected to one inverter circuit.

Therefore, when connected in series, the output voltage of two sets of windings is added in series to the semiconductor of one inverter circuit, and when the generator output fluctuates greatly, the semiconductor of the control circuit breaks down. There is a fear of being done. In addition, in the case of one inverter connected in parallel, a predetermined voltage cannot be obtained because the voltage is not added. In addition, there is a problem that there is a voltage difference, that is, an imbalance in the output of the generators connected in parallel, and a load is imposed on whichever voltage is higher.

Japanese Patent No. 4913234 JP 2012-44817 A JP 2007-280187 A JP 2000-308396 A JP 10-84700 A

The present invention does not employ a dummy resistance method or a reactance drop method, and further controls the maximum power generation voltage at no load and at high speed rotation at least half that of the prior art without requiring winding switching. It is an object of the present invention to provide a high-efficiency output-stabilized power generation apparatus that can step down all input voltages to a circuit without waste and can stabilize a wide range of input voltages with high efficiency without significant loss.

In addition, in the case of a high-efficiency small hydropower generation system that can generate power even when the running water head is small in an agricultural waterway, and in-vehicle generators, it is possible to charge the battery by simply adding the power generation outputs of multiple generators. It is an object of the present invention to provide an efficient output stabilization power generator.

That is, the above-described problems can be solved by the following embodiments.

(1) A power generator including one permanent magnet generator that is driven by a rotational drive source composed of any one of a windmill, a water turbine, and a rotating body of an automobile and whose output voltage varies according to the rotational speed, In the permanent magnet generator, n 1 / n output windings that are wound in parallel, where n is an integer greater than or equal to 2, and that 1 / n output voltage is obtained with respect to the rated output voltage; N rectifiers directly connected to each of the 1 / n output windings, and n rectifiers having the same structure connected to the n rectifiers and stabilizing the output voltage thereof. A control circuit including a DC / DC converter, and an addition connection unit for connecting the n number of step-down DC / DC converter output terminals in series to directly add the respective DC outputs in series to obtain a required voltage. High-efficiency output-stabilized power generation Location.

(2) The permanent magnet generator is a high-efficiency small hydraulic power generator driven by a turbine through a gearbox with a speed increase ratio of 5 to 8 times. A low-efficiency, low-power hydroelectric power generation system with at least two high-efficiency, stabilized power generators that can generate electricity with less than 0.5m of running water at intervals of 0.5m or more and less than 1.0m. Power generation system.

(3) An n-based permanent magnet generator driven by a rotational drive source composed of any one of a windmill, a water wheel, and an automobile rotating body, wherein n is an integer of 2 or more, and an output voltage changes according to a rotational speed. N generator coils, each of which is provided for each of the n permanent magnet generators, and 1 / n output windings that can obtain an output voltage of 1 / n with respect to a rated output voltage. N rectifiers of the same configuration directly connected to each of the n 1 / n output windings, and one to each of the n rectifiers, and the output thereof By connecting in series the control circuit including n number of step-down DC / DC converters having the same configuration for stabilizing the voltage and the output terminals of the n number of step-down DC / DC converters, each DC output can be directly used. The addition connection part which carries out serial addition and makes it a required voltage. A high-efficiency output-stabilized power generator.

Here, the rotating body as the rotational drive source includes not only an output shaft of a windmill or a water turbine and an axle of an automobile, but also a drum rotating around a fixed shaft in the case of a drum motor type generator, for example.

In this invention, the output voltage of the n output windings with the number of windings of the generator winding being 1 / n is rectified and the output voltage is stabilized by the step-down DC / DC converter ( For example, 280 / nVDC) is added in series to obtain 280VDC, so that the maximum input voltage (withstand voltage) of the rectifier diode, the high-speed switching element (Sic) for the step-down DC / DC converter, etc. at the maximum generator speed. The voltage within a range that does not exceed the range, for example, 1200 VDC or less, and further, by setting the winding to 1 / n, the winding inductance is halved to suppress the generation of counter electromotive force, and the drooping voltage inside the generator is reduced. The efficiency is further improved by reducing the power generation voltage. Furthermore, since the generated voltage is 1 / n of the conventional voltage, there is no need to switch windings, and the generator output is reduced in parallel with the load. It is not necessary to insert the over resistor and the external reactance, the generated voltage at a low loss from a low-speed rotation range to a high speed range efficiently stabilized may be utilized.

Further, n is a withstand voltage of the step-down DC / DC converter with respect to an input voltage Emax to one step-down DC / DC converter when the permanent magnet generator has the maximum rotation speed. When the maximum input voltage is Ew, Emax / n ≦ Ew is set so that the input voltage to the step-down DC / DC converter does not exceed the withstand voltage of the step-down DC / DC converter. The power generation efficiency can be increased without using a control circuit using high-cost elements.

Further, n is an allowable input voltage of the step-down DC / DC converter with respect to an input voltage Emax to one step-down DC / DC converter when the permanent magnet generator has the maximum rotation speed. When Ec is set, Emax / n ≦ Ec so that the input voltage to the step-down DC / DC converter does not exceed the controllable voltage of the step-down DC / DC converter. The power generation efficiency can be increased without using a control circuit using this element.

Here, the allowable input voltage is a voltage that can be controlled by the step-down DC / DC converter. If the generated voltage is lower than the maximum input voltage (withstand voltage), the element of the step-down DC / DC converter will not be destroyed. However, if the generated voltage frequently approaches the maximum input voltage, the element will deteriorate due to heat generation. In order to prevent this, an allowable input voltage is determined.

The present invention does not employ a dummy resistance method or a reactance drop method, and further sets the maximum power generation voltage at no load and at high speed rotation to 1 / n of the conventional, and does not require winding switching to the control circuit. Thus, it is possible to step down all input voltages without waste and to stabilize a wide range of input voltages with high efficiency without a large loss.

The circuit diagram which shows the circuit containing the output winding of the permanent magnet type generator in the high efficiency output stabilization electric power generating apparatus which concerns on Example 1 of this invention. Sectional drawing which shows typically the output winding of the permanent magnet type generator in Example 1 The circuit diagram which shows the detail of the pressure | voltage fall type DC / DC converter in Example 1 The diagram which shows the heat loss in the electric power generating apparatus of Example 1 in relation to a generated voltage and a rotational speed. Diagram showing similar heat loss in a conventional reactance descent power generator The perspective view which shows typically the Example of the flowing-water type small hydroelectric power generation system which installed the flowing-water type small hydroelectric power generation device which is a highly efficient output stabilization electric power generation apparatus in the small water channel, and was comprised. The diagram which compares and shows the turbine rotational torque at the time of using a 5 times gearbox when using this invention for a flowing water type small hydroelectric generator, and the turbine rotation torque at the time of using a 20 times gearbox A circuit diagram showing a circuit including an output winding of a permanent magnet generator in a high-efficiency stabilized output power generator according to a distributed embodiment in which 1 / n winding is divided into n permanent magnet generators Sectional drawing which shows typically the output winding of the permanent magnet type generator in the same Example Circuit diagram showing a case where four permanent magnet generators are used in a distributed embodiment. Diagram showing the output drooping characteristics of a permanent magnet generator and the load fluctuation characteristics of hydropower and wind power A circuit diagram showing a conventional power generator that suppresses the output voltage by the reactance drop method.

Hereinafter, a highly efficient output stabilization power generation apparatus (hereinafter referred to as a power generation apparatus) according to Embodiment 1 of the present invention shown in FIGS. 1 to 3 will be described in detail.

The power generation apparatus 10 according to the first embodiment includes a permanent magnet generator 20, a control circuit 30, and an addition connection unit 38, and applies an output voltage to the load 12.

The permanent magnet generator 20 is a three-phase AC generator, and the output windings of the U phase, V phase, and W phase are as shown in FIG. 2 for each of the U phase, V phase, and W phase. Are composed of two output windings in parallel. The number of turns of each output winding is halved so that the output voltage is halved with respect to the number of turns when the rated voltage is output.

Specifically, the U-phase output winding is composed of output windings 24U ₁ and 24U ₂ parallel to each other, the V-phase output winding is composed of output windings 24V ₁ and 24V ₂ parallel to each other, and the W-phase The output winding is composed of output windings 24W ₁ and 24W ₂ parallel to each other. That is, it consists of two parallel output windings 24U ₁ , 24V ₁ , 24W ₁ and 24U ₂ , 24V ₂ , 24W ₂ .

2 indicates a permanent magnet rotor, and 28 indicates a stator. The generator of the first embodiment is formed with 18 slots and 12 poles. In addition, the rotor 26 is driven from a rotary drive source 29 that is a rotating body such as a hydroelectric generator, a wind power generator, or an automobile axle through a speed increasing device 29A to increase the rotational speed.

The output voltages of these two output windings are stabilized independently for each system in the control circuit 30, and the two DC outputs are added in series by the addition connection unit 38, resulting in a load. The 2Y connection output serial addition method is configured.

This 2Y connection output serial addition method is a configuration in which the winding of the generator is Y-connected, and the output is made direct current, then stabilized by a step-down DC / DC converter and added in series. Indicates.

One of the two systems of three-phase alternating current output in the permanent magnet generator 20 is directly input to the three-phase rectifier 32-1, and the other is directly input to the three-phase rectifier 32-2, and is converted into direct current. The direct current outputs of the phase rectifiers 32-1 and 32-2 are stepped down separately in step-down DC / DC converters 34-1 and 34-2. In the first embodiment, the maximum 1200 VDC input is stepped down and stabilized to 140 VDC.

In step-down DC / DC converters 34-1 and 34-2, as shown in detail in FIG. 3, PWM switching elements 36-1 and 36-2 are provided so that only necessary power is supplied. ing. Although only the PWM switching element 36-1 of the step-down DC / DC converter 34-1 is shown in FIG. 3, the PWM switching element 36-2 of the step-down DC / DC converter 34-2 has the same configuration. Therefore, the illustration is omitted by indicating 36-1 (36-2).

The three-phase rectifiers 32-1 and 32-2 are exactly the same, and the step-down DC / DC converters 34-1 and 34-2 are also identical.

In the power generation apparatus 10 according to the first embodiment, two permanent magnet generators 20 are provided with two Y-connection coils each having a winding number ½ of the number of turns in the case of the rated output voltage ( 24U ₁ , 24V ₁ , 24W ₁ and 24U ₂ , 24V ₂ , 24W ₂ ) are set in parallel, the power generation outputs of the two systems are individually rectified, and the step-down DC / DC converter 34-1, 34-2 is stabilized, and the DC outputs of the step-down DC / DC converters 34-1 and 34-2 are added in series by the addition connection unit 38 to obtain a rated output (for example, DC 280V output).

In the first embodiment, the three-phase rectifiers 32-1 and 32-2 and the step-down DC / DC converters 34-1 and 34-2 are added to the control circuit 30 by adding the stabilized outputs in series. The applied voltage is 1/2 that of the system. That is, each input circuit (three-phase rectifiers 32-1 and 32-2) of the control circuit 30 has an applied voltage that is ½ that of the conventional one system.

Therefore, if the maximum generated voltage of each of the two systems does not exceed the withstand voltage of the electronic component of the control circuit 30, it is not necessary to suppress the generated voltage by switching the winding, and the electronic component with a relatively low withstand voltage. Since the circuit can be constructed using the, it can be mounted on a windmill or automobile in which the rotational drive source is rotated at a high speed. In addition, since a complicated winding switching technique is not required, the structure of the generator can be simplified, and a low-cost power generator that can be easily mass-produced can be configured.

Note that the number of turns of each of the above-described two systems of coils is ½ of the number of turns of the coil in the case of the rated output. In this case, 1/4,... Note that n is an integer of 2 or more.

More specifically, the n is obtained by a 1 / n output winding to the step-down DC / DC converters 34-1 and 34-2 when the permanent magnet generator 20 has the highest rotation speed. When the maximum input voltage which is the withstand voltage of the step-down DC / DC converters 34-1 and 34-2 is Ew with respect to the input voltage Emax rectified by the three-phase rectifiers 32-1 and 32-2, Emax A value satisfying / n ≦ Ew may be selected.

As an example, the input voltage Emax = 1854VDC, Ew = 1200VDC, Emax / Ew = 1.545≈2 (n) to one step-down DC / DC converter. However, 1200 VDC is a withstand voltage of the electronic components constituting the step-down DC / DC converter.

In addition, n is an allowable input voltage to the step-down DC / DC converter with respect to an input voltage Emax to one step-down DC / DC converter at the maximum rotation speed of the permanent magnet generator. When Ec is set, a value satisfying Emax / n ≦ Ec may be selected.

Regarding the energy loss, in the step-down DC / DC converters 34-1 and 34-2, the energy loss in the PWM switching elements 36-1 and 36-2 is the ON resistance (0.08Ω / 35A) of the FET + switching loss. + It is limited to the copper loss (0.04Ω) of the choke coil L and is very small.

Further, in the step-down DC / DC converters 34-1 and 34-2 shown in FIG. 3, the energy stored in the choke coil L is consumed by the load 12, so that no high spike voltage is generated and no heat is generated. It is extremely effective for making a wide range of input voltages (146V to 1200V) into a constant voltage output (for example, output voltage DC140V or DC280V), and energy loss is small.

Furthermore, the choke coil L requires an AC three-phase choke coil in the reactance descent method, but in this method, it can be configured with one DC power choke coil, which is light in weight, highly efficient, and low in cost. Can do.

Note that the rectifier is not limited to the one using a diode, and may be a rectifier by high-speed switching, for example.

[Experimental example]
In the permanent magnet generator that obtains the rated output of 280 VDC after rectification, two windings of U, V, and W phases are added together in parallel. 140 VDC was added in series after rectifying and stabilizing the power generation output of No. 1 to give a rated output E1 of 280 VDC. As a result, the generator windings were halved and power generation was possible as before. This can be expressed as E1 = 140 + 140 = 280 VDC.

Measured value of energy loss is shown in Fig.4. FIG. 5 shows heat loss when a reactance drop method is adopted in a permanent magnet generator for obtaining a similar output of E1 = 280 VDC.

4 and FIG. 5, it can be seen that the heat loss in the power generator of Example 1 is very small.

Next, the relationship between the power generator and the gearbox will be described.

In the flowing water type small hydroelectric generator, the wind power generator, and the in-vehicle generator using the permanent magnet generator as described above, the desired generated voltage can be obtained even when the rotation of the rotary drive source including the water turbine, the windmill, and the axle is low. A gearbox is used to make it available. However, when using a gearbox, the desired voltage can be obtained during low-speed rotation, but the generated voltage exceeds the maximum input voltage (withstand voltage) of the control circuit during high-speed rotation and no-load rotation. It will break the circuit.

On the other hand, in the first embodiment, the speed increasing ratio of the speed increasing device 29A is m, and the input voltage Emax to one step-down DC / DC converter at the maximum number of rotations during no-load rotation or high-speed rotation. On the other hand, when the allowable input voltage of the step-down DC / DC converter is Ec, the simulation results are as follows.

<Conditions>
(1) In a flowing water type small hydroelectric generator including a flowing water type small hydroelectric generator, a speed increasing device of about 20 times (speed increasing ratio m = 20) is generally used (power generation for one rotation of a water turbine). Machine 20 revolutions).
(2) Rotation and power generation voltage (voltage after three-phase rectification) at rated load (10 kW);
1000rpm (50rpm × 20) ⇒320VDC
(3) No-load rotation and generated voltage (voltage after three-phase rectification);
3200rpm (160rpm × 20) ⇒1024VDC ... (a)
(4) Permissible input voltage of grid interconnection device (power conditioner) ⇒ 600 VDC (b)

<Calculation>
(1) Countermeasures for no-load overvoltage: From (a) and (b), 1024 VDC / 600 VDC = 1.7≈2, n = 2 and 1/2 windings are two systems, and two sets of step-down DC Since it is shared by the DC converter, m = 20 may be left as a countermeasure against withstand voltage. ... (c)
(2) To support low-speed rotation, the number of reference windings (windings for obtaining a three-phase rectified output 320V at 1000 rpm) is set to two systems, and each stabilized output voltage is added in series (n = 2). Since the output voltage is doubled, the three-phase rectified output per system may be 320 VDC / 2 = 160 VDC. That is, the speed increasing ratio may be reduced to ½. ... (d)
From (c) and (d), the speed increasing ratio can be (20 times) × 1/2 = 10 times. ... (e)

The speed increase ratio can be further reduced in consideration of the generator torque. This will be described below.

Conventionally, since the generator torque × 20 = rotational torque of the turbine, when the speed increasing ratio is halved as described above, the generator torque × 10 = rotational torque of the turbine is also halved. Accordingly, the rotation of the water turbine increases as the rotational torque is reduced.

Since the rated load rotational speed of the water turbine to the no-load rotational speed is 50 to 160 rpm, the rotational speed of the torque 1/2 of the rated load rotational speed to the no-load rotational speed curve is obtained from FIG. ... (f)

If this speed is multiplied by a speed increase ratio of 10, 100 × 10 = 1000 rpm, so if there is a speed of 1000 rpm × 1/2 = 500 rpm per generator system from <Condition> (2), power generation of 2 systems The power generation voltage 160 VDC × 2 (= n) = 320 VDC at the rated load is obtained in the machine. ... (g)

Therefore, the speed increasing ratio can be further reduced to 1/2 (1 / n). Therefore, the speed increasing ratio can be set to 1/4 = 1 / n ² . That is, the corrected speed increase ratio m = 20 × 1/4 = 5 times. The final rotational speed of the water wheel is about 140 rpm from FIG. 7, and the rotational speed of the generator is 140 × 5 = 700 rpm. From (g), since the required rotational speed is 500 rpm, 700 rpm is a sufficient rotational speed.

In conclusion, when the speed increase ratio of the speed increaser when obtained with a permanent magnet generator assuming that the rated output voltage is 1 (n = 1) is m ₀ , the speed increase ratio of the speed increaser m can be m = m ₀ / n ² .

<Confirmation of rotation speed at rated load and rotation speed at no load>
From FIG.
(1) The rated load rotation saturation point is 10 Kg · m because the speed increasing ratio is 5, and the rotation speed is about 140 rpm. Therefore, 140 rpm × 5 = 700 rpm is the rotation speed at the rated load.
(2) The rotation speed at no load is 160 rpm × 5 = 900 rpm (maximum rotation speed).
(3) The generated voltage at the rotation speed at the rated load is 320 VDC × 700 rpm / 1000 rpm = 224 VDC, and 140 VDC is generated from the 224 VDC. ... (h)
(4) The generated voltage at the no-load rotation speed is 320 VDC × 900 rpm / 1000 rpm = 288 VDC, and 140 VDC is generated from this 288 VDC. ... (i)
(5) According to (h) and (i), the stabilization voltage 140V of each of the two systems is added in series in both cases of rotation at the rated load and no-load rotation of the turbine to generate a total of 280 VDC, It can be input to the grid interconnection device.

Here, the change in efficiency by changing the speed increase ratio of the speed increaser of the high efficiency small hydroelectric generator from 20 to 5 will be described.
(1) Water energy due to head: P0 = flow rate (m ³ / s) × gravity acceleration (9.8 m / s ² ) × head (m)
= 0.88 x 9.8 x 1 = 8.62 kW
However, the flow rate of 0.88 m ³ / s and the drop of 1 m are measured values (2) Energy generated by rotating the turbine: P1 = 2πn _r / 60 × N · m where n _r = turbine speed (rpm)
= 2 × 3.14 × 50/60 × 500 N · m = 2.617 kW
Speed increaser 20 times (water turbine 1 rotation ⇒ generator 20 rotation)
However, 500 N · m is the value of the rated load rotation saturation point of FIG.
(3) Efficiency calculation: When the speed increasing ratio is 20, P1 / P0 × 100 = 2.617 / 8.62 × 100 = 30%
(4) Efficiency calculation: When the speed increase ratio is 5, there is no change in the force received by the turbine: 500 N · m
The rotation speed of the water wheel is from Fig. 7: 140rpm
P2 = 2πn _r / 60 × N · m where n _r = turbine speed (rpm)
= 2 × 3.14 × 140/60 × 500 N · m = 7.326 KW
P2 / P0 × 100 = 7.326 / 8.62 × 100≈85%

In the conventional generator, the phenomenon that the rotation torque due to the load current is applied to the water turbine while the rotation speed is increased 20 times by the speed increaser and the rotation is reduced is 5 times the speed increase ratio (m = 5). The torque applied to the water wheel is reduced to ¼, and the rotation speed of the water wheel is improved from 50 rpm to 140 rpm as calculated above.

As a result, the generated voltage can be secured at low speed, and the change in the number of revolutions during no-load operation and rated load operation can also be reduced. By using these, the efficiency of the flowing-water small hydroelectric generator can be improved from 30% to 85%. did it. Even in the range of 5.0 <m ≦ 7.5, the efficiency could be less than 85% and 50% or more.

In addition, what used to generate 5 kW of electricity with a running water drop of 1 m can be used for the same power generation of 5 KW or more with a running water drop of 0.5 m. It becomes possible to install a plurality of flowing water type small hydroelectric generators. For example, like the flowing water type small hydropower generation system 40 shown in FIG. 6, the flowing water drops f ₁ , f ₂ , f ₃ , f ₄ ... Can be generated by continuously installing a plurality of (two or more) flowing-water small

hydroelectric generators

44A, 44B, 44C, 44D. Reference numeral 43 in FIG. 6 indicates a weir provided in the small water channel 42. This blocks water and forms a running water drop.

Note that the speed increaser is applied not only to a hydroelectric power generator but also to a wind power generator or an in-vehicle power generator.

Next, simulation results when the power generation device of Example 1 is used for a vehicle will be described.

The rotational speed of an automobile diesel engine is 600 rpm at a low speed and 3500 rpm at a high speed. When this speed is increased by a speed increaser with a speed increase ratio of 2.5 times, the rotational speed of the input shaft of the generator is 1500 rpm to 8750 rpm. .

Based on this rotational speed, the generated voltage of the 2Y connection output series addition method of Example 1 from FIG. 4 and the reactance drop method of FIG. 5 are as follows.

4, the no-load phase voltage maximum is 400 VAC, the line voltage is 400 × √3 = 692 VAC, and the rectified output is 692 × √2 = 969 VDC, whereas the reactance of FIG. In the drop method, the maximum no-load phase voltage is 700 VAC, the line voltage is 700 × √3 = 1121 VAC, and the rectified output is 1211 × √2 = 1707 VDC.

Therefore, with the 2Y connection output serial addition method of the first embodiment, the entire rotation region (1500 to 8750 rpm) of the generator can be controlled without switching the winding, whereas the reactance drop method has a line voltage. Therefore, it can be understood that control cannot be performed without using winding switching.

Next, the energy loss comparison by the difference of 2Y connection output serial addition system and reactance descent system about this power generator for vehicles was simulated as generator speed 4000rpm.

From FIG. 4, at 4000 rpm, the control unit loss is 50 W (DC circuit), whereas in FIG. 5, the heat loss at 4000 rpm is 1200 W (the apparent power is obtained by converting 400 W between the lines). It can be seen that energy is wasted in parallel with the load.

Comparing the two efficiency, in the 2Y connection output serial addition method, if the loss is 50 W × 2 with respect to the input of 3.13 KVA, the output is 3.03 KVA, and the control unit efficiency is 3.03 / 3.13 ×. 100 = 96.8%. That is, an epoch-making high efficiency could be obtained.

On the other hand, in the reactance descent method, since the loss is 1.2 kW with respect to the input 3.13 KVA, the output is 1.93 KVA, and the efficiency is 1.93 / 3.13 × 100 = 61.7%. Thereby, in the case of the electric power generating apparatus which concerns on a present Example, it turns out that 61.7% conventionally is improved to 96.8%.

Hereinafter, a highly efficient output stabilization power generation device (hereinafter referred to as a power generation device) 100 according to a distributed embodiment in which the 1 / n winding shown in FIGS. 8 to 9 is divided into n permanent magnet generators will be described in detail. explain. In addition, the same code | symbol is attached | subjected to the structure same as the structure in Example 1, and description is abbreviate | omitted.

The power generation device 100 includes two permanent magnet generators 20-1 and 20-2 having the same configuration, a control circuit 30, and an addition connection unit 38, and applies an output voltage to the load 12. To do.

The permanent magnet generators 20-1 and 20-2 are three-phase AC generators, and are rotational drive sources that are two output shafts such as a left and right wheel shaft before or after a water turbine, a windmill, or an automobile. 72A and 72B are connected in parallel, and are rotationally driven almost synchronously by rotational drive sources 72A and 72B via speed increasers 73A and 73B, respectively, and are three-phase alternating currents of U phase, V phase, and W phase, respectively. It is designed to generate electricity.

The output windings 24U ₁ , 24V ₁ , 24W ₁ and 24U ₂ , 24V ₂ , 24W ₂ of the U phase, V phase, and W phase in the two permanent magnet generators 20-1 and 20-2 are: The number of turns is set to 1/2 so that the output voltage becomes 1/2 with respect to the number of turns when the rated voltage is output.

Further, the windings of 24U ₁ , 24V ₁ , 24W ₁ , 20-2 of 24U ₂ , 24V ₂ , 24W ₂ of the _two permanent magnet generators 20-1 are output in parallel with the two units. Has been.

7 denotes a permanent magnet rotor, and 28 denotes a stator. In addition, the generator of a present Example is formed with 18 slots and 12 poles. Further, the rotor 26 rotates from the rotational drive sources 29-1 and 29-2, which are two rotating bodies such as a hydroelectric generator, a wind power generator, or an automobile axle, through speed increasers 29A-1 and 29A-2. The speed is increased and driven almost synchronously.

One of the two systems of three-phase AC outputs that are the outputs of the two permanent magnet generators 20-1 and 20-2 is directly connected to the three-phase rectifier 32-1, and the other is directly connected to the three-phase rectifier 32-2. Input and individually converted into DC, and further, the DC outputs of the three-phase rectifiers 32-1 and 32-2 are individually stepped down in the step-down DC / DC converters 34-1 and 34-2. ing. In the first embodiment, the maximum 1200 VDC input is stepped down and stabilized to 140 VDC.

The step-down DC / DC converters 34-1 and 34-2 have the same configuration as in the first embodiment shown in FIG.

In the power generation apparatus 100 according to this distributed type embodiment, two systems (24U ₁ , 24V ₁ , 24W ₁ , 24U ₁ ) of Y connection coils each having a winding number ½ of the winding number in the case of the rated output voltage are used. ₂ , 24V ₂ , 24W ₂ ) are set independently for the two permanent magnet generators 20-1 and 20-2, and the two permanent magnet generators 20-1 and 20-2 Are individually rectified and individually stabilized by the step-down DC / DC converters 34-1 and 34-2, and the DC outputs of the step-down DC / DC converters 34-1 and 34-2 are added and connected. The unit 38 adds in series to obtain a rated output (for example, DC 280V output). Further, in the case of hydroelectric power generation or wind power generation, the power added in series may be supplied to a commercial power source connected to the grid as, for example, a 200 V three-phase alternating current through the grid interconnection device.

In this embodiment, the three-phase rectifiers 32-1 and 32-2 and the step-down DC / DC converters 34-1 and 34-2 are added to the control circuit 30 by adding the stabilized outputs in series. In this case, the applied voltage is ½. In other words, each input circuit (three-phase rectifiers 32-1 and 32-2) of the control circuit 30 has an applied voltage that is ½ that of the conventional one system.

The coils of the two permanent magnet generators 20-1 and 20-2 have the number of turns of each coil being ½ of the number of turns of the coil at the rated output. , 1/3 when the number of generators is 3, 1/4 when the number of generators is 4,... 1 / n when the number of generators is n. Note that n is an integer of 2 or more (hereinafter the same).

More specifically, the n is a 1 / n output to the step-down DC / DC converters 34-1 and 34-2 when the permanent magnet generators 20-1 and 20-2 are at the maximum rotation speed. The maximum input voltage, which is the withstand voltage of the step-down DC / DC converters 34-1 and 34-2, is obtained with respect to the input voltage Emax obtained by winding and rectified by the three-phase rectifiers 32-1 and 32-2. When Ew is set, a value satisfying Emax / n ≦ Ew may be selected.

The experimental example, the relationship between the power generation device and the speed increaser, the conditions, the calculation, the rotational speed at the rated load, and the confirmation of the rotational speed at the load are substantially the same as those in the first embodiment.

In the conventional method of adding the outputs of two generators in parallel, there is a problem that if the two voltages do not substantially match, an imbalance occurs and current concentrates on either power source. . In a vehicle power generator, it is conceivable to install one generator on each of the left and right wheel shafts. However, when the vehicle is not in a straight traveling state, a rotational speed difference occurs between the left and right wheel shafts, and stabilization is achieved. Therefore, the output voltage of the two generators could not be added conventionally.

In the case of the above-described vehicle power generation device, the output voltage can be added even if there is a difference in the rotation speed between the two generators driven by the left and right wheel shafts, resulting in an output voltage difference. Accordingly, in order to obtain a predetermined voltage from only one shaft in the conventional vehicle generator, it is necessary to use a high-cost power generator or speed increaser. In the case of the first embodiment, a low-cost power generator is used. Since electric power can be efficiently obtained from the left and right wheel shafts and both output voltages can be added, it is possible to obtain electric power that is 2 times or n times that of the prior art, particularly in a low speed region.

When the power generator of the distributed embodiment is used for a vehicle, the two permanent magnet generators are separately attached to, for example, two rotating bodies that rotate with front and rear left and right wheels. In this case, the simulation result is the same as when the first embodiment is used for a vehicle.

Next, a highly efficient output stabilization power generation device (permanent magnet power generation device) 50 according to a distributed embodiment in which n = 4 shown in FIG. 10 will be described.

The permanent magnet power generator 50 includes four permanent magnet generators 60-1, 60-2, 60-3, 60-4, a control circuit 70, and an addition connection section 72. Each of the permanent magnet generators 60-1, 60-2, 60-3, 60-4 is driven to rotate four times through the gearboxes 51-1, 51-2, 51-3, 51-4. Connected to sources 50-1, 50-2, 50-3, 50-4.

The control circuit 70 includes four three-phase rectifiers 62-1, 62-2, 62-3, 62-4, step-down DC / DC converters 64-1, 64-2, 64-3, 64-4, PWM System switching elements 66-1, 66-2, 66-3, 66-4 are included.

Other configurations are denoted by the same reference numerals as those shown in FIGS. 8 and 9, and the description thereof is omitted.

For example, in the case of a vehicle, the n = 4 permanent magnet power generation device 50 is configured to rotate each of the wheel shafts of a four-wheeled vehicle or the four wheel shafts of a trailer as rotational drive sources 50-1, 50-2, 50-3, 50. -4.

In this embodiment, even if the rotational speeds of the four wheel shafts are not synchronized, the generated power can be added to a voltage to obtain a high voltage. The upper limit value of n is determined in the same manner as in the first embodiment.

In wind power and hydropower generation, n stabilized outputs are added in series to obtain a high voltage (for example, 1000 VDC), long-distance transmission is performed, and an output voltage such as 280 VDC is output by a high-efficiency step-down DC / DC converter on the power receiving side. Obtainable. Conventionally, power transmission with AC high voltage has been mainly performed, but this method enables high voltage power transmission with DC method without using a transformer.

This means that if the power generation location and the power usage location are separated, it will greatly contribute to the reduction of wiring material costs, the reduction of transmission loss, and the like.

When a plurality of generators are provided on a single shaft, the torque of a permanent magnet type generator is T = Kt * Ia (Kt: torque multiplier, Ia: current), and n generators are attached to each. When the load current flows, it becomes n × T, and a large load torque is applied to the turbine and windmill, resulting in a reduction in the rotational speed. This is suitable when the generator is rotated by an external force or when the rotational speeds of a plurality of rotary drive shafts vary as in the specific example of the second embodiment.

In addition, when three or more micro wind power generators or hydroelectric power generators are installed in a narrow area, even if there is a variation in the output of each generator, the total output can be added to obtain a high voltage. it can.

The above-described permanent magnet power generator for a vehicle is always driven to rotate by wheels, an axle, or an engine output shaft. However, the present invention is not limited to this. It may be one that generates power only during operation.

1. As a permanent magnet generator for vehicles, small size and light weight is a necessary condition, but this method is extremely useful because it can be used with a single winding from low speed range to high speed range without switching winding. Since the 2Y connection output serial addition method is used, the generated voltage per winding is 1 / n compared to the conventional method. This is characterized in that the circuit configuration can be established without using a high breakdown voltage semiconductor element that has a maximum generated voltage of 1 / n compared with the prior art during high-speed rotation and is very expensive. Therefore, it can be used as an on-vehicle generator.

2. For micro hydraulic power and micro wind power, in the present invention, when the number of turns is the same as the conventional one, the rotational speed is 1 / n compared with the conventional one, two power generation coils are provided, and the stabilized output is added in series. By setting the ratio to 1 / n, the speed increase ratio to the water wheel and windmill can be reduced, and their rotation increases, so the number of rotations can be further reduced to 1 / n, and the power generation output voltage is as usual with a speed increase ratio of 1 / n. It is. In hydropower and wind power generation, there is a problem of how much power is generated at low speed rotation, and therefore, there is a possibility of use as micro hydropower generation and micro wind power generation devices.

Japanese Patent Application No. 2013-075073 filed on March 29, 2013 and Japanese Patent Application No. 2013-182593 filed on September 3, 2013 and Japan filed on September 3, 2013 The disclosures in the specification, drawings, and claims of patent application number 2013-182594 are each hereby incorporated by reference in their entirety.

10, 50, 100 ... High-efficiency output stabilization power generator 12 ... Load 20, 20-1, 20-2, 60-1, 60-2, 60-3, 60-4, ... Permanent magnet generator 29, 29-1, 29-2, 50-1, 50-2, 50-3, 50-4...

Rotation drive source

29A, 29A-1, 29A-2, 51-1, 51-2, 51-3, 51 -4 ...

Speed increaser

30, 70 ... Control circuit 32-1, 32-2, 62-1, 62-2, 62-3, 62-4 ... Three-phase rectifiers 34-1, 34-2, 64-1 , 64-2, 64-3, 64-4 ... step-down DC / DC converters 36-1, 36-2, 66-1, 66-2, 66-3, 66-4 ...

PWM switching elements

38, 72 ... Additional connection section 40 ... Flowing small hydroelectric power generation system 42 ...

Small channel

44A, 44B, 44C ... Flowing small hydraulic power generation Location

Claims

A power generator including one permanent magnet generator that is driven by a rotational drive source composed of any one of a windmill, a water wheel, and a rotating body of an automobile, and whose output voltage varies according to the rotational speed,
In the permanent magnet generator, n 1 / n output windings that are wound in parallel and when n is an integer equal to or larger than 2 can obtain an output voltage of 1 / n with respect to a rated output voltage;
N rectifiers of the same configuration directly connected to each of the n 1 / n output windings, and n rectifiers of the same configuration connected to the n rectifiers and stabilizing the output voltage. A control circuit including a step-down DC / DC converter;
By connecting the n number of step-down DC / DC converter output terminals in series, each DC output is added in series as it is to obtain a required voltage;
A high-efficiency output-stabilized power generator.
In claim 1,
The n is a maximum input which is a withstand voltage of the step-down DC / DC converter with respect to an input voltage Emax to one step-down DC / DC converter when the permanent magnet generator is at the maximum rotation speed. A high-efficiency output-stabilized power generation device, wherein Emax / n ≦ Ew when the voltage is Ew.
In claim 1,
The n is the allowable input voltage of the step-down DC / DC converter with respect to the input voltage Emax to one step-down DC / DC converter when the permanent magnet generator is at the maximum rotational speed. A high-efficiency output-stabilized power generator, wherein Emax / n ≦ Ec.
In any one of Claims 1 thru | or 3,
The permanent magnet generator is configured to be driven by the rotary drive source via a speed increaser, and is composed of one set of output windings assuming that the rated output voltage is n = 1. High efficiency, characterized in that when the speed increase ratio of the speed increaser when obtained with a permanent magnet generator is m 0 , the speed increase ratio m of the speed increaser is m = m 0 / n 2 Output stabilization power generator.
In any one of Claims 1 thru | or 4,
The permanent magnet generator is configured to be driven by a water turbine through a speed increaser, and one permanent magnet comprising one system of output windings assuming that the rated output voltage is n = 1. When the speed increasing ratio of the speed increaser when obtained with a power generator is m 0 , the speed increasing ratio m of the speed increaser is m = m 0 / n 2. ,
A high-efficiency output-stabilized power generation device characterized in that power generation is possible with running water having a running water drop of 0.5 m or more and less than 1.0 m.
A flowing water type small hydroelectric power generation system in which at least two high efficiency output stabilizing power generation devices according to claim 5 are continuously installed in a water channel at intervals where a flowing water drop of 0.5 m or more and less than 1.0 m is obtained.
A power generator including n permanent magnet generators driven by a rotational drive source composed of any one of a windmill, a water wheel, and a rotating body of an automobile, wherein n is an integer of 2 or more, and output voltage varies according to the rotational speed Because
N number of 1 / n output windings, each of which is provided for each of the n permanent magnet generators, to obtain an output voltage of 1 / n with respect to a rated output voltage;
Each of the n 1 / n output windings is directly connected to each of n rectifiers having the same configuration, and each of the n rectifiers is connected to each of the output voltages. A control circuit including n identical step-down DC / DC converters to be stabilized;
By connecting the output terminals of the n step-down DC / DC converters in series, each DC output is added in series as it is, and an addition connection unit for obtaining a required voltage;
A high-efficiency output-stabilized power generator.
In claim 7,
The n is a maximum input which is a withstand voltage of the step-down DC / DC converter with respect to an input voltage Emax to one step-down DC / DC converter when the permanent magnet generator is at the maximum rotation speed. A high-efficiency output-stabilized power generation device, wherein Emax / n ≦ Ew when the voltage is Ew.
In claim 7,
The n is the allowable input voltage of the step-down DC / DC converter with respect to the input voltage Emax to one step-down DC / DC converter when the permanent magnet generator is at the maximum rotational speed. A high-efficiency output-stabilized power generator, wherein Emax / n ≦ Ec.
In any one of Claims 7 thru | or 9,
Each of the n permanent magnet generators is configured to be driven by the rotary drive source via a speed increaser, and includes one output winding assuming that the rated output voltage is n = 1. When the speed increase ratio of the speed increaser when obtained with one permanent magnet generator is m 0 , the speed increase ratio of the speed increaser is m = m 0 / n 2 Efficient output stabilization power generator.
In any of claims 7 to 10,
The rotational drive source is a rotating body that rotates independently with the left and right wheels on the front or rear side of the automobile, and the n permanent magnet generators are attached to the rotating body one by one. A high-efficiency output-stabilized power generator characterized in that the two permanent-magnet generators are provided.
In any of claims 7 to 10,
The rotational drive source is a rotating body that rotates together with four wheels of an automobile, and the n permanent magnet generators are four permanent magnet generators attached to the rotating body one by one. A high-efficiency output-stabilized power generator characterized by being.