JPS62189996A - Constant-voltage variable frequency power generator - Google Patents

Abstract

PURPOSE:To increase the generating efficiency by controlling rotational speed of a generator drive means in accordance with a load power. CONSTITUTION:A gas engine 1 is adjusted in supply flow rate corresponding to opening degree of a governor 2. Power generated by a generator 3 rotating in interlocking with the gas engine 1 is supplied through inverters INV 1 and INV 2 to a pump P and a fan F. A load power detector 6 for detecting the total load power consumed by respective load devices is connected to output side of a generator 3, and the governor 2 is adjusted in the opening degree corresponding to the power detection signal of the load power detector 6. Thus the decrease of the generating efficiency can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention provides a method for controlling the rotational speed of the generator in accordance with the load power when the generator is rotated by a gas engine or the like to generate the required power. This invention relates to a power generation device for controlling the power supply and generating constant voltage variable frequency power.

(Prior Art) Conventionally, a so-called CVCF (constant voltage, constant frequency) power generation device is used, in which a generator is rotated by, for example, a gas engine, and the voltage and frequency of generated power are controlled to be constant regardless of fluctuations in load power. Alternatively, a so-called VVVF (variable voltage, variable frequency) power generation device was adopted, which controls the voltage and frequency of generated power in response to fluctuations in air conditioning load (flow rate, temperature, etc., hereinafter the same).

(Problems to be Solved by the Invention) When the conventional CVCF power generation system is used to supply electric power to, for example, an air conditioner, the air conditioner has large seasonal load fluctuations, and when the load is light, for example, the power generation Even if the machine's load factor (load power/generator rated capacity) becomes 50%, the generator will continue to operate at the same rotation speed 'C, so the power generation efficiency will be reduced to 10% when the load factor is 50%.
There was a problem that it decreased by about 6% compared to when it was 0% and ended up at 1 no.

Furthermore, when the conventional VVVF power generation device is employed to supply power to an air conditioner, for example, the frequency and voltage of the power output from the generator are controlled to change in response to fluctuations in the air conditioning load. However, the capacity of the generator (nominal capacity at that frequency) decreases in approximately linear proportion to the frequency, whereas the power required for the air conditioning load power equipment (pumps, fans, etc.) decreases in approximately cube proportion to the frequency. Therefore, when the frequency decreases (during light air conditioning load), the generator becomes a partial load and the power generation efficiency decreases. For example, when the air conditioning load becomes 70%, the generator's electric JMo2 frequency and capacity will become 70%, but the load power will be about 35%, so the load factor of the city owner (load power / generator capacity) will be 70%. ) becomes 50%, and the power generation efficiency is reduced by about 6% compared to when the load factor is 100%.

Therefore, in the present invention, by detecting the load power, controlling the rotation speed of the generator driving means according to the load power, and controlling the frequency of the power output from the generator in accordance with the load power, Since the load factor of the generator is always kept close to 100%, the power generation efficiency does not decrease.In addition, the constant voltage variable frequency power output from the C generator can be used as a load drive device corresponding to each air conditioning load condition. It is a technical problem to be solved by converting and supplying each load device.

(How to solve the problem gf) The technical means for solving the above problem is to use a constant voltage variable frequency power generation device to generate electric power at a constant voltage and at a frequency corresponding to the rotation speed. , a generator driving means for rotating the generator, an energy supply device for supplying the necessary driving energy to the generator driving means, and a generator for each of the 11 Corresponding to the load condition of the load device 1) Detect the load power that is the sum of the required power of the power conversion device that converts the voltage and frequency into the load driving power and the respective load devices 4, NtI. A signal corresponding to the zero charge power is output to the energy supply device and the same channel 1! - A configuration including a load power detector etc. for controlling the energy supply to the generator drive means via the supply device.

(Function) According to the above configuration, when the load power detector detects the load power and outputs a signal corresponding to the load power to the energy supply device, the energy supply device applies drive energy corresponding to the load power to drive the generator. means is supplied and driven to rotate the generator in response to the load power. The generator generates constant voltage variable frequency power corresponding to the load power,
Output to the power conversion device. The power conversion device converts the constant voltage variable frequency power into load driving power having a voltage and frequency corresponding to the load state of the load device, and supplies it to the load device to drive it.

(Example) Next, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a system of a power generation device according to an embodiment of the present invention. The gas engine 1 rotates using, for example, 13A city gas as one energy, the supply flow rate of which is adjusted in accordance with the opening degree of the governor 2 (including the fuel control valve, hereinafter the same).

The generator 3 that rotates in conjunction with the gas engine 1 is, for example, a three-phase brushless synchronous generator, and the voltage of the power generated by the generator 3 is controlled by the excitation current of the generator 3 by an excitation current control device (not shown). The voltage is controlled at a constant voltage of, for example, 210V. Further, the frequency of the generated power is varied, for example, in the range of 30 to 60 H2 depending on the rotation speed of the generator 3. Departure', 1ffl! The output side of i3 is the pump P of the air conditioner 4.
an inverter INV1 whose load device is the pump drive motor M1 that drives the air conditioner 4, and an inverter I whose load device is the fan drive motor M2 that drives the fan F of the air conditioner 4.
It is connected to NV2, electronic ballast fluorescent lamp 5, etc.

The inverters rNV1 and INV2 are supplied with constant voltage variable frequency power generated by the generator 3, and transfer the required power of the pump P and the pump drive motor M to the pump drive motor M.
1 and fan drive motor M2.

The voltage and frequency of the load driving power are varied, for example, within a range of 5 to 100%, depending on the power required for the load. -b1 The electronic ballast fluorescent lamp 5 receives power whose voltage is constant even if the frequency of the power generated by the generator 3 changes (J causes the fluorescent lamp to blink.

A load power horn detector 6 for detecting the total load power consumed by each load generator 3 is connected to the output side of the generator 3, and the load power horn detector 6 detects the load power λ1. 11a outputs the corresponding power detection number 43 to the banner 2. The opening degree of the gas pump 2 is controlled according to the voltage level of the power detection signal blade, so that the flow of gas supplied to the gas engine 1 corresponds to the load power. 1-1
1- will be checked. As a result, the gas engine 1 rotates in accordance with the load power and rotates the generator 3, so the power generation R3
The frequency of the power generated by η fluctuates in response to the load power.

Next, Takeda of this embodiment will be explained. Initially, the governor 2 is controlled to the standard opening degree, and when fuel and 4T gas are supplied to the gas cone engine 1, the gas engine 1 rotates at the standard rotational speed, and the generator 3 rotates in conjunction. When the rotational speed of the generator 3 reaches a predetermined reference rotational speed, an exciting current is applied to the generator 3 to start power generation, and the 210V6
The generated power of 011Z is transferred to the inverter INV1.011Z. INV
2 and the electronic ballast fluorescent lamp 5, the inverter INV1 supplies a rated voltage F of, for example, 210V60tlZ to the pump drive regulator M1 that drives the pump 1) of the air conditioner 1.
The inverter INV2 outputs the same rated driving power to the fan drive motor M2 that drives the fan of the air conditioner 4, and also outputs the driving power of the same rated frequency to the fan drive motor M2 that drives the fan of the air conditioner 4. Generated power is also supplied to the light 1. When the pump driver 1111IE- motor M1 and the fan drive motor M2 are driven and the C pump [) and the fan `` are rotated, the air conditioner F?'I starts operating, and each The room is air-conditioned. As the air conditioning of each room progresses and the room temperature reaches the set humidity, the power required for the pump P and fan F decreases, so the load power of 1 - 1 tal decreases. The power detector 6 detects the same load power,
The detected load'gravity-compatible power detection signal is sent to the governor'
-2, the opening degree of the C governor 2 is reduced, and the flow of gas supplied to the gas engine 1 is reduced. As a result, the rotational speed of the gas engine 10 becomes low Iτ and the rotational speed of the generator 3 also decreases, so that the frequency of the power generated by the light heavy equipment 3 becomes, for example, /1. It drops to OH2. Note that the voltage of the power generation horn remains at 210V because it is controlled by the C constant voltage by the excitation current control device.

From generator 3, 2 10 V 4Q corresponding to the load power
147 power is output and the inverters INVI and IN
V2 inputs the same power, converts the power so that the rotational speed of the pump [2] and fan F is at an optimum state, and supplies the power to the pump drive motor M1 and fan drive motor M2.

As described above, according to this embodiment, even if there are multiple air conditioners, the power load of each air conditioner is always supplied with overvoltage and optimal frequency power by an individual inverter. The generator output fluctuates and C always maintains high power generation efficiency.Therefore, this power generator is suitable for use in general buildings, multi-tenant buildings, hospitals, etc. that require integrated air conditioning. Energy saving -V- can also be achieved in the pill.

In addition, Fig. 2 is a graph showing the power generation efficiency of a power generation device according to an embodiment of the present invention and a conventional CVCF power generation device with respect to the load factor, and the graph Δ indicates the power generation efficiency of an embodiment of the present invention. Graph B shows the power generation efficiency of the conventional c v CF power generation device. It is clear from the figure that according to the present invention, even if the load factor drops to 50%, the power generation efficiency only drops to about 31%, but in the case of the conventional CV CF power generation device, the load factor drops to 50%. It has been shown that if this happens, the power generation efficiency will drop to about 25%, resulting in a ``C''.

(Effects of the Invention) As described above, according to the present invention, load power is detected on the output side of the generator, and a signal corresponding to the load power is output to the generator drive means to rotate the generator drive means. the output frequency of the generator is controlled in accordance with the load power, and the output voltage of the generator is controlled to a constant voltage and output to the C-Mino-J converter; Since the voltage and frequency corresponding to the load condition of the load device are converted into a load-driven horn between the city power conversion stations and the load device is driven, power generation is possible even when the load factor is low. This makes it possible to drive the machine according to the total load power, which has the effect of preventing low power generation efficiency and realizing energy savings.

[Brief explanation of drawings]

FIG. 1 is an overall system diagram of an embodiment of the present invention, and FIG. 2 is a comparison characteristic diagram of power generation efficiency between the conventional technology and this embodiment. 1... Gas engine 2... Governor 3... Generator 4... Air conditioner 5... Electronic ballast fluorescent lamp 6... Load power detector

Claims (1)

[Claims] A generator that generates power at a constant voltage and a frequency corresponding to the number of rotations, a generator drive means for rotating the generator, and an energy supply device that supplies required driving energy to the generator drive means. , a power conversion device that receives the power generated by the generator and converts it into load driving power having a voltage and frequency corresponding to the load state of each load device; and a power conversion device that totals the required power of each of the load devices. and a load power detector that detects the load power and outputs a signal corresponding to the load power to the energy supply device to control the amount of energy supplied to the generator driving means via the energy supply device. Characteristic constant voltage variable frequency power generation device.