JPS6223256Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a cooling water supply device for a rotating electric machine.

Turbine generators and their auxiliary equipment installed in thermal power plants are equipped with a large number of coolers that cool them with fresh water.

FIG. 1 shows a conventional example of a cooling water system for a hydrogen gas-cooled turbine generator and its auxiliary equipment.

The system of this device includes a group of coolers that control the amount of water and a group of coolers that do not control the amount of water.

That is, a water supply bus 3 provided with a cooling water pump 1 with a constant discharge amount and a cooling water cooler 2 using seawater is branched into two, a water supply pipe 3a and a water supply pipe 3b, on the downstream side thereof. One water supply pipe 3a has gas coolers 4a and 4c for cooling the hydrogen gas inside the generator.
4D are connected in parallel.

These gas coolers 4 are connected to the suction side of the cooling water pump 1 through a drain pipe 5.
is provided with a two-way flow control valve 6 that automatically controls the amount of water in accordance with the temperature rise value of the generator by a control device (not shown).

In addition, the other water supply pipe 3b includes an air cooler 7a that cools the exciter directly connected to the generator, an oil cooler 7b that cools the bearing lubricating oil, and a pure water cooler that directly cools the generator stator winding. 7c and an air cooler 7D for cooling the outlet bus bar of the generator, etc. are connected in parallel. The cooler 7 is connected to the suction side of the cooling water pump 1 via a drain pipe 8. In other words, the flow path of this device is designed to supply two types of parallel-connected coolers in a closed loop.

The supply device configured in this manner has the advantage of simplifying the pipe network because it can supply cooling water to a large number of cooler groups with one pump. The provided two-way flow rate control valve 6 has the advantage of being able to control the amount of water to match seasonal drops in cooling water temperature or light load operation of the generator (for example, 90% load).

However, as the base load of electricity supply has recently shifted to nuclear power generation, thermal power plants have been required to operate at partial loads such as 50% load or 25% load. During such partial load operation, according to this device, the two-way flow control valve 6 operates to extremely reduce the amount of water passing through the gas cooler 4.

Then, since the cooling water pump 1 is set to always supply the necessary discharge flow rate to all the coolers 4 and 7 at the rated load, the excess water will inevitably flow to the water supply pipe 3b, that is, the cooler 7 side. It flows into the channel.

This excess water supercools the cooler 7, causing dew condensation especially in the air coolers 7a and 7D, and accelerates erosion of the cooling pipes due to excessive flow rate.

Furthermore, when the two-way flow control valve 6 is throttled so that the valve opening becomes 30% or less, the differential pressure across the valve becomes excessive, causing problems in terms of noise, vibration, erosion, and durability of the valve. Therefore, if the surplus water is discharged to the outside of the device, there is a drawback that drainage and water supply equipment must be added.

The present invention was developed in consideration of the above points, and its purpose is to provide one cooler for both coolers that control water volume in response to changes in heat loss and other coolers that do not control water volume. To provide a cooling water supply device for a rotating electric machine configured to supply water in a closed circuit using a constant discharge amount pump, and suppressing changes in the flow rate of other coolers even when the water volume of a cooler is controlled. be.

The present invention will be explained below based on the embodiment shown in FIG. In FIG. 2, the same parts as in FIG. 1 are given the same reference numerals, and the explanation will be omitted, and only the different points will be explained.

That is, a three-way flow control valve 9 is installed in the drain pipe 5 of the gas cooler 4 instead of the two-way flow control valve 6 shown in FIG.
will be established. This valve 9 is arranged so that two sides are inlets a and b and the other side is an outlet c of the mixed water. Furthermore, it branches from the water supply pipe 3a of the gas cooler 4, and connects this water supply pipe 3a with the inlet a of the three-way flow control valve 9.
A bypass pipe 10 is provided to connect the
A throttle device 11 is provided in the middle of this tube 10.

This throttling device 11 is composed of an externally adjustable flow rate regulating valve or orifice.

Then, the opening degree of the three-way flow control valve 9 is adjusted so that an amount of water corresponding to the load of the generator flows into the gas cooler 4, and the opening degree of the throttling device 11 is adjusted so that excess water flows.

With this configuration, even if the three-way flow control valve 9 in the flow path is throttled in order to flow the gas cooler 4 with an amount of water commensurate with the partial load operation loss of the generator, the excess water is removed from the flow path by the throttling device 11. It flows into a bypass pipe 10 whose resistance is properly adjusted.

Therefore, even if the cooling water pump 1 with a constant discharge amount is used, the other cooler 7 always tries to supply a constant amount of water.
It is possible to suppress the inflow of excess water to prevent problems such as excessive flow rate and overcooling.

In addition, the three-way flow control valve 9 on the gas cooler 4 side is
Even if this valve opening is reduced to 30% or less, surplus water will flow into the outlet side of the valve from the other pipe line, so unlike the conventional two-way flow control valve 6, there is a difference between the front and rear of the valve. The pressure is reduced and problems such as noise, vibration, and erosion can be prevented.

As described in detail above, according to the configuration of the present invention, even if the water volume of the cooler 4 is controlled, changes in the water volume of other coolers connected in parallel with the cooler 4 can be suppressed, thereby preventing supercooling or overcooling of the other coolers. , can prevent overflow.

[Brief explanation of the drawing]

Figure 1 is a system diagram of a conventional cooling water supply system;
The figure is a system diagram of a cooling water supply device showing an embodiment of the present invention. 1...Cooling water pump, 2...Cooling water cooler, 4
... Cooler, 7 ... Other cooler, 9 ... Three-way flow control valve, 10 ... Bypass pipe, 11 ... Throttle device.

Claims (1)

[Scope of utility model registration request] A single cooling water pump equipped with a cooling water cooler circulates between the cooler 4, which controls the amount of water in response to temperature changes in the rotating electric machine, and another cooler 7, which is connected in parallel with this cooler and does not control the amount of water. In the cooling water supply device having a pipe line configured as shown in FIG. A cooling water supply device for a rotating electrical machine, characterized in that the bypass pipe is further provided with a throttle device.