CN201569553U - Water leakage monitoring device of direct current converter valve - Google Patents

Abstract

The utility model discloses a water leakage monitoring device of a direct current converter valve, in particular to a cooling water leakage detecting device of the direct current converter valve of an electrical power system. A water collecting device is arranged at the bottom of the direct current converter valve and comprises a water collecting bucket, a floating body and a sunshade board, wherein the sunshade board is provided with a light transmission hole; an optical transmitter and an optical receiver are respectively arranged at both sides of the light transmission hole; and the optical transmitter and the optical receiver are connected with a water leakage monitoring logic circuit on a valve base electronic (VBE) by an optical cable. When the water leakage monitoring device of the technical scheme works, the external energy is not needed, no electronic device exists in the components, only simple mechanical parts exist; the water leakage monitoring device is characterized by simple structure, high reliability and the like, can monitor the water leakage condition of the direct current converter valve and gives out alarming or tripping signals according to the water leakage condition.

Description

A water leakage monitoring device for DC converter valve

technical field

The utility model relates to a water leakage detection device, in particular to a cooling water leakage detection device for a DC converter valve in an electric power system.

Background technique

The DC converter valve is the core equipment of the DC transmission project. By sequentially connecting the three-phase AC voltage to the DC terminal to obtain the desired DC voltage and realize power control, its value accounts for about 22-25% of the total price of the complete set of equipment in the converter station. %. During the operation of the DC converter valve, the internal saturated reactor, thyristor, damping resistor, and DC equalizing resistor generate large power consumption, which makes the equipment seriously heated; for this reason, a certain cooling technology must be used to ensure that the DC converter valve safe and reliable operation. Early DC converter valves were air-cooled and oil-cooled, both of which have relatively large disadvantages. Air cooling cannot satisfy the current large-capacity DC converter valve equipment, and oil cooling makes it difficult to keep the valve hall of DC converter valves clean. Currently, substations require no oil. In the past ten years, DC converter valves have adopted water-cooling technology, which has great advantages over air-cooling and oil-cooling in various aspects. The total capacity of cooling water has a significant impact on the heat dissipation effect of the DC converter valve. Under the premise of constant cooling water flow rate, the heat dissipation capacity of the DC converter valve is proportional to the total cooling water capacity. However, since there are many cooling water pipe joints for the DC converter valve, and most of the cooling water pipes inside the DC converter valve are non-metallic water pipes, and the radiator is made of aluminum, the current of the DC converter valve is not a constant value. The change of the current leads to the change of the water temperature. Although the water cooling system It can be adjusted according to the inlet water temperature of the valve, but under normal working conditions, the cooling water temperature of the valve still has some fluctuations, and the DC converter valve also has a start and stop phase, at which time the cooling water temperature changes greatly. Due to the different materials and expansion coefficients of the cooling water pipe and the radiator, the cooling water pipe of the DC converter valve may leak water during operation, which may cause overheating of the DC converter valve, affect the safety of the DC converter valve, and even cause the DC converter valve to be damaged. forced outage.

In order to ensure the normal operation of the DC converter valve cooling water system, DC converter valve leakage monitoring technology is currently used. The traditional DC converter valve leakage monitoring equipment is installed at the bottom of the DC converter valve tower. The DC converter valve leakage monitoring equipment is an active device. trip signal. Since the bottom of the DC converter valve tower is at a high potential, it is difficult to provide energy for active water leakage monitoring equipment; for this reason, laser energy delivery is usually used to provide the required energy for water leakage monitoring equipment. However, the cost of laser energy transmission is high, and there are many electronic components in water leakage monitoring equipment, so there is a possibility of failure. If the electromagnetic energy transmission method is used, the bottom of the DC converter valve tower is the part with the highest DC transmission voltage, so it is usually given up because of the high isolation voltage.

Utility model content

In order to solve the problems of high cost and many electronic components of the laser detection device for DC converter valves in the prior art, the utility model provides a simple converter valve water leakage detection device without electronic devices and purely mechanical structure. The specific scheme is as follows, a The water leakage monitoring device of the DC converter valve includes an optical cable, an optical transmitter and an optical receiver, and is characterized in that a water collection device is installed at the bottom of the DC converter valve, and the water collection device includes a water collection bucket, a floating body and a light shield. There is a light hole on the shading plate, and the light emitter and the light receiver are installed on both sides of the light hole, and the light emitter and the light receiver are connected with the leakage monitoring logic circuit 4 on the valve base electronics (VBE) through an optical cable .

Another preferred mode of the present utility model: there are two sets of the light transmitter and the light receiver, and the light-transmitting hole includes an alarm hole and a trip hole. The length of the hole, the two sets of light transmitters and light receivers are respectively installed at the two ends of the alarm hole and the trip hole and are connected to the water leakage monitoring logic circuit through an optical cable.

Another preferred mode of the present utility model: the long sides of the trip hole and the alarm hole are parallel to the longitudinal axis of the shading plate and the tops are at the same horizontal position.

Another preferred mode of the present utility model: the alarm hole and the trip hole are located on the same vertical axis.

Another preferred mode of the utility model: the floating body and the shading plate are integrated.

Another preferred mode of the present utility model: the water collecting bucket is a pit on the base of the converter valve.

In this scheme, a water collection device is installed at the bottom of the DC converter valve, and a floating body is placed in the water collection device. According to the amount of water leakage, the floating body will rise to a corresponding height. Using the principle of light emission and reception, the light-transmitting holes of the light-shielding plate on the floating body will be adjusted accordingly. The rise of the water level will block the connected light, and the height of the water level determines whether the light shield can pass through the light signal, thereby measuring the amount of water leakage. The logic circuit issues a trip command only when there is no return signal from the alarm hole and the trip hole, which greatly reduces the possibility of malfunction. The water leakage monitoring equipment of this scheme does not require external energy when it works. There are no electronic devices in the components, only simple mechanical components. It has the characteristics of simple structure and high reliability. It can monitor the leakage of the DC converter valve and give an alarm according to the seriousness of the leakage. or trip signal.

Description of drawings

Fig. 1 structural representation of the utility model

Fig. 2 Schematic diagram of different opening positions of the alarm hole and the trip hole of the shading plate of the utility model

Detailed ways

As shown in Figure 1, the DC converter valve leakage monitoring device of this scheme can be divided into two parts according to its installation position. The leakage detection part is installed at the bottom of the DC converter valve tower, including the water collection bucket 1, the floating body 2, and the shading plate 3. Two sets of light transmitters 8 and light receivers 9, among which there are two holes on the shading plate 3, which are divided into alarm holes 6 and trip holes 7 according to the level of alarms. Both the alarm holes 6 and the trip holes 7 are rectangular holes. , and the trip hole 7 is longer than the alarm hole 6, which can reflect different alarm effects, and adopts a rectangular or similar hole, which can allow the light to shake in a range, and when exceeding the range, a corresponding alarm signal will be sent. The floating body 2 is installed in the water collecting barrel 1, the light shielding plate 3 is installed on the floating body 2, and the light transmitter 8 and the light receiver 9 are installed in pairs at the two ends of the alarm hole 8 and the trip hole 9 respectively. The other part is the water leakage monitoring logic circuit 4, which is installed on the valve base electronics (VBE) side and is at ground potential. It is connected with the optical transmitter 8 and the optical receiver 9 through the optical cable 5, and the logic circuit 4 sends a pulse signal with a frequency of 20 Hz. The optical signal is transmitted to the optical receiver 9 through the optical cable 5, and the optical signal is transmitted to the optical transmitter 8 at the other end of the alarm hole 6 and the trip hole 7 by the optical receiver 9. After receiving the signal, the optical transmitter 8 will feed back to the The logic circuit 4 forms a loop, and the device utilizes the on-off of the optical signal loop to judge whether there is water leakage.

The water collection bucket in this solution can be a container, or a pit can be directly opened on the base of the bottom of the DC converter valve tower to form a water accumulation area, and then the floating body and other components can be installed inside.

The floating body and the shading plate in this scheme can be made into an integral type.

In the judgment of the logic circuit, it can be set as the alarm signal when the light is turned on, or it can be set as the alarm signal when it is blocked, only need to change the shading plate. The location of the alarm hole and the trip hole can be arranged in various ways. For example, the top of the alarm hole and the trip hole are located at the same horizontal position. At this time, the long sides of the alarm hole and the trip hole are parallel to the longitudinal axis of the shading plate; Holes and tripping holes are arranged on the upper and lower positions of the same longitudinal axis of the shading plate. In the above embodiments, the optical transmitter and the optical receiver are respectively located on both sides of the alarm hole and the trip hole. It only needs to enable the light between the light transmitter and the light receiver to be connected or blocked.

The working process of this device is as follows:

Normal situation: First, a pulse signal with a frequency of 20 Hz is sent from the water leakage monitoring logic circuit of Valve Base Electronics (VBE), and the signal is sent to the optical receiver at the bottom of the DC converter valve tower through a high-voltage optical cable. If the light signal passes through the alarm hole and the trip hole, the light transmitter at the other end will feed back the signal to the water leakage monitoring logic circuit board of the valve base electronics (VBE), indicating that everything is normal.

Alarm situation: If the DC converter valve leaks water, the water will raise the floating body, and then the shading plate will rise, the light emitted by the light receiver will be blocked by the gradually rising alarm hole, and the light emitter at the other end of the alarm hole cannot receive light. Signal, when the water leakage monitoring logic circuit cannot receive the light signal fed back by the light transmitter of the alarm hole, but can receive the signal fed back by the light transmitter at one end of the trip hole, an alarm signal will be sent.

Trip situation: If the DC converter valve leaks water, the water will raise the floating body. At this time, the shading plate rises, and the rise of the water level makes the shading plate block the optical signals from the optical receiver at the end of the alarm hole and the trip hole. The light transmitter at the other end of the alarm hole and the trip hole cannot receive the light signal. When the water leakage monitoring logic circuit cannot receive the light signal returned by the light transmitter of the alarm hole and the trip hole at the same time, a trip signal will be sent.

Claims (6)

1. DC converter valve water leakage monitoring device, comprise optical cable (5), optical transmitting set (8) and optical receiver (9), it is characterized in that, in the DC converter valve bottom captation is installed, described captation comprises dust-collecting bucket (1), buoyancy aid (2) and shadow shield (3), described shadow shield has light hole on (3), described optical transmitting set (8) and optical receiver (9) are installed in the both sides of light hole, and optical transmitting set (8) and optical receiver (9) are connected with water leakage monitoring logical circuit (4) on the valve base electronics (VBE) by optical cable (5).

2. water leakage monitoring device as claimed in claim 1, it is characterized in that, described optical transmitting set (8) and optical receiver (9) have two covers, described light hole comprises warning hole (6), tripping operation hole (7), warning hole (6), tripping operation hole (7) are shaped as strip, the length in tripping operation hole (7) is greater than the length of warning hole (6), and described two cover optical transmitting sets (8) are installed in the two ends in warning hole (6) and tripping operation hole (7) respectively with optical receiver (9) and are connected with described water leakage monitoring logical circuit (4) by optical cable (5).

3. water leakage monitoring device as claimed in claim 2 is characterized in that, and top parallel with the longitudinal axis of shadow shield (3), the long limit of described tripping operation hole (7) and warning hole (6) is positioned at same horizontal level.

4. water leakage monitoring device as claimed in claim 2 is characterized in that, described warning hole (6) and tripping operation hole (7) are positioned on the same vertical axis.

5. as claim 3 or 4 described water leakage monitoring devices, it is characterized in that described buoyancy aid (2) is an integral type with shadow shield (3).

6. water leakage monitoring device as claimed in claim 5 is characterized in that, described dust-collecting bucket (1) is the pit on the converter valve pedestal.

Images