JP2656565B2 - Power supply device for self-powered system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention connects a common generator to a distribution line distributed from a substation to a plurality of consumers, and supplies power from the substation and uses the common generator. The present invention relates to a power supply device in a self-powered system that supplies power required by a plurality of consumers by supplying power.

<Prior Art> Currently, a plurality of consumers share a generator for private use, and the power from the substation (hereinafter referred to as “shared power”) cannot be covered by the power from the substation (hereinafter referred to as “shared power”). A so-called self-powered system supplemented by "commercial power") has been proposed.

FIG. 4 is a schematic view showing a power supply device of a conventional self-powered system. The power supply device in the self-powered system includes a bus (3) on a low voltage side of a transformer (2) of a substation (1).
And the bus (3) is connected to a plurality of distribution lines (4a).
(4b) ... Branches to (4n) and the distribution lines (4a) (4b) ... (4
(n) to each customer (5a) (5b) ... (5n) and the distribution lines (4a) (4b) ... (4n) to the connection lines (6a) (6b) ... (4 6n) and a shared power distribution system to which a shared generator (7) is connected. The integrated wattmeter for transaction (91) and the integrated wattmeter for consumer (92) are connected to the distribution lines (4a) (4b) ... (4n) on the substation side and the customer side, respectively, and the connecting line (6a ) (6b)… (6n)
And an integrated wattmeter (93) for a shared generator. Hereinafter, the distribution line (4), the customer (5), and the connection line (6) are abbreviated as a distribution line (4), a customer (5), and a connection line (6), unless otherwise indicated. , Common generator (7) to connecting line (6), distribution line (4)
Supply shared power to each customer (5) through
Commercial power can be supplied from the transformer (2) of the substation (1) to each customer (5) through the distribution line (4). Therefore, the power that cannot be covered by the shared power can be supplemented by the commercial power from the substation (1).

Then, the shared power is counted by the integrated wattmeter for common generator (93) interposed and connected to the connecting line (6), and the commercial power is counted by the integrated wattmeter for transaction (61). Is recorded by the customer's laminated power meter (92).

<Problems to be Solved by the Invention> However, in the power supply device having the above configuration, the shared power and the commercial power cannot be shared according to the allocation ratio. Has been supplied. Therefore, there is a problem that one of the customers (5) can use the shared power beyond the allocation.

If the power consumption of one customer (5a) with respect to the shared power is less than the power consumption of the other customers (5b) ... (5n), the balance of the allocation ratio is broken and the surplus power is connected. Point → Distribution line (4a) → Bus (3) → Distribution line (4b)…
It is supplied to other consumers via (4n) (the flow of current is illustrated by an arrow in FIG. 4). That is, a reverse power flow occurs. In order to prevent reverse power flow, the output of the shared generator must be reduced according to the power demand with low power consumption.
Other consumers will not be able to take full advantage of the shared power allocation.

The present invention has been made in view of the above problems, and has as its object to provide a power supply device in a self-powered system that can suppress a reverse power flow.

<Means for Solving the Problems> In order to achieve the above object, a power supply device in the self-powered system according to the first aspect of the present invention includes a power supply device between each distribution line distributed to a plurality of consumers and a shared generator. And a series reactor in which a reactance inversely proportional to the allocation ratio of each consumer to the output of the shared generator is connected.

The power supply device in the self-powered system according to the second aspect of the present invention is configured such that, between each distribution line distributed to a plurality of customers and the shared generator, the allocation ratio of each consumer to the output of the shared generator is inversely proportional. Reactance is set in series reactor,
And phase adjusting means for changing the phase of the output voltage according to the power supplied from the shared generator to each customer.

<Operation> According to the invention of claim 1 described above, a common generator is connected to a distribution line distributed from a substation to a plurality of consumers, and power supply from the substation and power supply from the common generator are performed. By
When supplying the required power of a plurality of customers, between each distribution line distributed to the plurality of customers and the shared generator,
By connecting a series reactor with a reactance inversely proportional to the allocation ratio of each customer to the shared generator, power can be distributed and supplied from the shared generator according to the allocation of each customer. In addition, generation of reverse power flow between distribution lines can be suppressed.

According to the second aspect of the present invention, the power supply amount is set according to the allocation by the series reactor, and the phase of the output voltage supplied from the shared generator to each customer is advanced by the phase adjusting means in the forward direction, Alternatively, by shifting in the delay direction and adjusting the supply capacity of the shared power according to the power consumption of each customer, it is possible to suppress the reverse power flow generated due to the uneven power consumption of each customer. .

More specifically, the equation for the tidal power P is P
= 12sin δ / (where 1 is the potential of the shared generator (7), 2 is the potential of the substation, δ is 1 and 2
Is the reactance of the series reactor).

Then, by adjusting the impedance between the private power generation system and the substation by the series reactor, the shared power can be distributed according to the allocation ratio. further,
By adjusting the phase difference δ by the phase adjusting means, it is possible to suppress the reverse power flow generated due to the uneven power consumption of each customer.

<Embodiment> Hereinafter, an embodiment of a power supply device in a self-powered system according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a power supply device in a self-powered system according to the first aspect of the present invention. The power supply device in the self-powered system includes a transformer (2) of a substation (1).
A bus (3) is connected to the low-voltage side of, and the bus (3) is branched into a plurality of distribution lines (4a) (4b)... (4n), and the distribution lines (4a) (4b). Each customer (5a) (5b)… (5n)
And the above-mentioned distribution line (4a)
(4b) ... (4n) is connected to the shared generator (7) via connecting lines (6a) (6b) ... (6n), and the connecting lines (6a) (6b) ... (6
n), a reactance inversely proportional to the allocation ratio of each customer (5a) (5b) ... (5n) is set, and a series reactor (8a)
(8b) ... a shared power distribution system with (8n) interposed. And the distribution lines (4a) (4b) of the substation (1) ...
(4n), the customer-side distribution lines (4a), (4b) ... (4n) are provided on the integrated wattmeter for transactions (91) and the integrated wattmeter for consumers (9
2) and an integrated wattmeter (93) for the shared generator is connected to the connecting lines (6a) (6b) ... (6n)
A series reactor (8) is abbreviated unless a specific series reactor is indicated).

In more detail, the series reactor (8)
Is for distributing and supplying the shared power according to the allocation ratio of each customer (5). That is, the series reactor with the lowest reactance is connected to the distribution line (4) connected to the customer with the highest allocation, and the series reactor (8) with the highest impedance is connected in the order of decreasing allocation ratio. As the series reactor (8), it is possible to use a variable reactor in addition to a fixed reactor.

The operation of the power supply system having the above configuration is as follows.

In the normal state, that is, when the consumers are consuming more power than the allocated power, the shared power is reduced by the series reactor (8) in which a reactance inversely proportional to the allocation ratio of each customer (5) is set. Distribution is performed according to each allocation ratio. The distributed power is supplied to each customer (5) through the connection line (6) and the distribution line (4). On the other hand, for the electric power used beyond the allocation, commercial electric power is supplied through the distribution line (4).

That is, since each customer (5) does not use the shared power beyond the respective allocation, the consumption balance of the shared power can be maintained in accordance with the allocation ratio, and the reverse power flow can be controlled. it can.

Therefore, the shared generator (7) can be operated at full power.

On the other hand, if the power consumption of one customer, for example, the customer (5a) is less than the allotment, the shared generator (7) is operated at full power and the bus from the distribution line (4a) of the customer (5a). (3) Surplus power is supplied to other customers (5b) to (5n) via distribution lines (4b) to (4n) (reverse power flow occurs).

In this case, the power generation output of the shared generator (7) is adjusted so that the allocated portion is distributed to the customers (5a) under the allocated portion, thereby suppressing the reverse power flow.

The present invention is not limited to the above embodiment. For example, instead of connecting series reactors to all of the distribution lines (4a) (4b). Connect a series reactor to the electric wires (4a) (4b) ... (4n)
The allocation ratio of all customers (5) can be set by the reactance of one series reactor, and other various design changes can be made without changing the gist of the present invention.

FIG. 2 is an embodiment showing a power supply device in the self-powered system according to the second aspect of the present invention.
FIG. A is a schematic diagram of a power supply device in a self-powered system, and FIG. 2B is a block diagram illustrating an example of a phase conversion inverter. The difference from the power supply device in the self-powered system in FIG. 1 is that the series reactors (8a) (8b).
Instead of n), connect transformers (81a) (81b) ... (81n) and phase-converting inverters (82a) (82b) ... (82n) to each connecting line (6a) (6b) ... (6n) (Hereinafter referred to as
Except for a specific transformer and a phase conversion inverter, the transformer (81) and the phase conversion inverter (82) are abbreviated).

The transformer (81) is interposed and connected to the connecting line (6), and has a reactance set in inverse proportion to the allocation ratio of each customer (5).

The phase conversion inverter (82) includes a rectifier (83) connected to the connection line (6), a smoothing capacitor (84), and an AC signal for adjusting the phase of the voltage supplied to the connection line. Switching circuit injected into (81) (8
5) and a control circuit (86) that generates a switch signal for generating the AC signal based on the pulsating signal from the rectifier (83) and outputs the signal to the switch circuit (85). That is, the phase conversion inverter (82) detects the phase of the voltage applied to the connection line, generates an AC signal for shifting this phase, and injects the AC signal into the transformer (81), thereby allowing each consumer to make a transition. The phase of the shared power distributed to (5) is adjusted. The phase conversion inverter (82)
Can switch the voltage of the battery to generate an AC voltage, and can take in the voltage of the connection line (6) through a transformer and a rectifier (83). is there.

The operation of the power supply device in the self-powered system is as follows.

In the normal state, that is, when each consumer (5) uses more power than the allocation, the shared power is distributed according to the allocation ratio by the reactance component of the transformer (81). Then, the shared generator (7) is operated at full power.

On the other hand, when the power consumption of one customer is less than the allotment, the shared generator (7) is operated at full power, and the distribution line (4a) of one customer, for example, the customer (5a) is connected to the bus (3). ) Is supplied to the other consumers (5b) ... (5n) (reverse power flows indicated by arrows in FIG. 2). In this case, the phase conversion inverter (82)
Thereby, based on the signal from the secondary side of the transformer (81), the phase of the power supplied to one customer (5a) through the connection line (6a) is detected, and the power is supplied through the connection line (6a). By adjusting the phase difference between the electric power and the commercial electric power, it is possible to suppress the reverse power flow caused by the power consumption of the customer (5a) being equal to or less than the allocation.

FIG. 3 shows a control flowchart of the phase conversion inverter (82). In step, a control flow is started, and in step, power consumption is measured based on a signal from the connection line (6).

In the step, the magnitude of the total power consumption and the total allocated power are compared, and if it is determined that the total power consumption is larger than the total allocated power, in the step, it is determined whether or not reverse power flow has occurred, If it is determined that a reverse power flow has occurred, then in a step, it is determined whether or not the power consumption is greater than the minimum power that can be adjusted by the phase conversion inverter (82). ) To determine the power consumption of the phase conversion inverter (8
If it is determined that the power is larger than the minimum power that can be adjusted in 2), the phase difference between the commercial power and the shared power is adjusted in step and the process returns to step.

In the above step, if it is determined that the total power consumption is smaller than the total allocated power, or if it is determined in step that the power consumption is not larger than the minimum power that can be adjusted by the phase conversion inverter (82), Then, the shared power amount is adjusted according to the power consumption of each customer, and the processing of the step is performed. Also, when it is determined in the above step that the reverse power flow has not occurred, the process returns to the step.

It should be noted that the present invention is not limited to the above-described embodiment, and for example, a phase transformer,
It is also possible to use a series reactor with OLTC.

<Effect of the Invention> According to the invention of claim 1 described above, between each distribution line distributed to a plurality of customers and the shared generator, the allocation ratio of each customer to the shared generator is inversely proportional. The series reactor with the set reactance allows the power to be distributed and supplied from the shared generator according to the allocation of each customer, so the occurrence of reverse power flow between distribution lines can be suppressed. It works.

According to the invention of claim 2, while the power supply is set according to the allocation by the series reactor, the phase adjusting means advances the phase of the output current supplied from the shared generator to each consumer in the forward direction, Alternatively, it is shifted in the delay direction, and a unique effect that a reverse power flow generated due to non-uniform power consumption of each consumer can be suppressed is achieved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a power supply device in a self-powered system according to the invention of claim 1, FIG. 2 is a diagram showing a power supply device in a self-powered system according to the invention of claim 2, and FIG. FIG. 4 is a schematic diagram showing a power supply device in a conventional self-powered system. (4) ... distribution line, (5) ... customer, (6) ... connecting line, (7) ... common generator, (8) ... series reactor, (81) ... transformer, (82) ) …… Phase conversion inverter

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakuni Asano 47-47 Umezu-Takaune-cho, Ukyo-ku, Kyoto-shi, Kyoto (72) Inventor Kazuhiko Onishi 47-47, Umezu-Takaune-cho, Ukyo-ku, Kyoto-shi, Kyoto Nissin Electric (56) References JP-A-61-102127 (JP, A) JP-A-49-13325 (JP, A) JP-B-38-2938 (JP, B1)

Claims (2)

(57) [Claims] A power generator is connected to a distribution line distributed from a substation to a plurality of consumers, and a power supply from the substation and a power supply from the common generator are used to supply power required by the plurality of customers. In the device for supplying the, between each distribution line distributed to a plurality of consumers and the shared generator, a series reactor in which a reactance inversely proportional to the allocation ratio of each consumer to the output of the shared generator is set. A power supply device in a self-powered system, wherein the power supply device is connected. 2. An apparatus for supplying power required by a plurality of customers according to claim 1, wherein each of the distribution lines distributed to the plurality of customers and the common generator have a respective output with respect to an output of the common generator. In addition to a series reactor in which a reactance inversely proportional to the allocation ratio of the customer is set, phase adjusting means for adjusting the phase of the output voltage according to the power supplied from the shared generator to each customer is connected. Power supply in self-powered systems.