阅读说明：本技术 基于uwb的变电站巡检定位方法 (Substation inspection localization method based on UWB ) 是由 孙海渤 魏刚 王智睿 唐健 李迎涛 阮爱民 于 2019-09-05 设计创作，主要内容包括：本发明公开了一种基于UWB的变电站巡检定位方法,包括：标签A进入搜索阶段,寻找可供测距的基站；测距过程中,基站B与标签A会进行三次信息传递,标签A向基站B发送poll消息,标签A记录下此时时间戳t1,基站B收到poll消息后经过一段延时后发送确定消息RNG消息给标签A,并记录下此时时间戳t2,标签A收到RNG消息后记录下此时时间戳t3,经过一段延迟后,标签A将所记录的时间戳附在final消息发送给基站B,基站B收到final消息并记下此时时间戳t4；求得基站与标签之间的距离d＝c*t,服务器每隔固定时间段120ms根据定位算法算出标签当前的坐标。本发明降低时钟漂移影响,不要求设备间时间同步,提高定位精度。(The invention discloses a kind of substation inspection localization method based on UWB, comprising: label A enters the search phase, finds the base station for ranging；In ranging process, base station B and label A will do it tertiary information transmitting, label A sends poll message to base station B, label A records timestamp t1 at this time, base station B sends determining message RNG message to label A after receiving poll message after one section of delay, and record timestamp t2 at this time, label A records timestamp t3 at this time after receiving RNG message, after one section of delay, the timestamp recorded is attached to final message and is sent to base station B by label A, and base station B receives final message and writes down timestamp t4 at this time；The distance between base station and label d=c*t are acquired, server calculates the current coordinate of label according to location algorithm every fixed time period 120ms.The present invention reduces clock drift effect, does not require equipment room time synchronization, improves positioning accuracy.)

1. a kind of substation inspection localization method based on UWB, which comprises the following steps:

1) label A enters the search phase, finds the base station for ranging, and base station is set as four or more, and label A is when fixed Prolong and message blk is sent using broadcast type, the base station B for receiving message blk signal replys one message package of label A, in message package Carry the ID of the base station；

2) in ranging process, base station B and label A will do it tertiary information transmitting, and label A sends poll message, label to base station B A records timestamp t1 at this time, and base station B is received after poll message by one section of delay t_reBAfterwards send determine message RNG message to Label A, and timestamp t2 at this time is recorded, label A records timestamp t3 at this time after receiving RNG message, by a Duan Yanchi t_reAAfterwards, the timestamp recorded is attached to final message and is sent to base station B by label A, and base station B receives final message and writes down Timestamp t4 at this time；Remember t_A=t3-t1, t_B=t4-t2；

Base station B extracts the timestamp in final message, calculates the skyborne flight time TOF of wireless signal,

In practical projects, the influence for considering chip clock drift, then measure the flight time are as follows:

e_AFor the clock drift of base station, e_BFor the clock drift of label；

3) propagation rate of known signal is electromagnetic wave rate, acquires the distance between base station and label d=c*t, and wherein c is electricity Magnetic wave rate 3*10⁸M/s, t are to measure flight time TOF_c；

4) each base station sends range data to server, and server is calculated every fixed time period 120ms according to location algorithm The current coordinate of label,

If the three-dimensional coordinate of each base station is x_i, y_i, z_i, i=1,2 ... n, n >=4, the tag A coordinates that need to be positioned are x, y, z, label A Distance to each base station is d_i, transfinited with least square solution and determine the mode of equation group, acquire the three-dimensional coordinate of label A；

Specifically: range formula is expressed as AX=b,

Using least square solution range equation, the least square location estimation of label is acquired are as follows:

X=(A^TA)^-1A^Tb。

2. the substation inspection localization method based on UWB as described in claim 1, which is characterized in that the t_reA、t_reBSetting For 40ms.

3. the substation inspection localization method based on UWB as described in claim 1, which is characterized in that in step 4),

If weighting matrix is W,

Acquire weighted least-squares location estimation are as follows:

X=(A^TWA)^-1A^TWb。

4. the substation inspection localization method based on UWB as claimed in claim 3, which is characterized in that the W1 value range It is 0~1.

Technical field

The present invention relates to a kind of substation inspection localization method based on UWB, belongs to electric power O&M technical field.

Background technique

The safe and effective operation of electric system is people's daily life, industry and the important leverage of agricultural production, substation It is a wherein indispensable ring.In substation operation maintenance process, needs to carry out equipment periodical inspection, checks, in time It was found that and processing equipment failure or hidden danger, handle accident abnormality situation, with guarantee equipment safety operate normally.Due to electric field The complexity and risk of operation, electric power field work management are always electricity safety production and its important link, can often be gone out Existing maloperation and security risk.

Electric power operation maintenance personnel has certain risk when electric field carries out inspection, to equipment operation, so needing Substation inspection personnel's inspection route is accurately positioned, to guarantee the life security of staff.

According to the above demand, power department generally uses the substation inspection positioning system based on UWB, and patrol officer wears Positioning is wirelessly communicated between wireless tag, with object of reference (base station).It is wireless compared to other since substation's indoor environment is complicated Location technology, ultra wide band (Ultra-wideband, UWB) have strong antijamming capability, very bandwidth is wide, transmission rate is fast, power It consumes that small, temporal resolution is high and many advantages such as positioning accuracy is high, substation inspection system can be suitable for.

Summary of the invention

The purpose of the present invention is to provide a kind of substation inspection localization method based on UWB reduces clock drift effect, Equipment room time synchronization is not required, improves positioning accuracy to Centimeter Level.

The purpose of the present invention is achieved by the following technical programs:

A kind of substation inspection localization method based on UWB, comprising the following steps:

1) label A enters the search phase, finds the base station for ranging, and base station is set as four or more, and label A is every solid Fixed response time sends message blk using broadcast type, and the base station B for receiving message blk signal replys one message package of label A, message The ID of the base station is carried in packet；

2) in ranging process, base station B and label A will do it tertiary information transmitting, and label A sends poll message to base station B, Label A records timestamp t1 at this time, and base station B is received after poll message by one section of delay t_reBIt sends afterwards and determines that message RNG disappears It ceases to label A, and records timestamp t2 at this time, label A records timestamp t3 at this time after receiving RNG message, by one section Postpone t_reAAfterwards, the timestamp recorded is attached to final message and is sent to base station B by label A, and base station B receives final message simultaneously Write down timestamp t4 at this time；Remember t_A=t3-t1, t_B=t4-t2；

Base station B extracts the timestamp in final message, calculates the skyborne flight time TOF of wireless signal,

In practical projects, the influence for considering chip clock drift, then measure the flight time are as follows:

e_AFor the clock drift of base station, e_BFor the clock drift of label；

3) propagation rate of known signal is electromagnetic wave rate, acquires the distance between base station and label d=c*t, wherein c For electromagnetic wave rate 3*10⁸M/s, t are to measure flight time TOF_c；

4) each base station sends range data to server, and server is every fixed time period 120ms according to location algorithm The current coordinate of label is calculated,

If the three-dimensional coordinate of each base station is x_i, y_i, z_i, i=1,2 ... n, n >=4, the tag A coordinates that need to be positioned be x, y, z, The distance of label A to each base station is d_i, transfinited with least square solution and determine the mode of equation group, acquire the three-dimensional coordinate of label A；

Specifically: range formula is expressed as AX=b,

Using least square solution range equation, the least square location estimation of label is acquired are as follows:

X=(A^TA)^-1A^Tb。

The purpose of the present invention can also be further realized by following technical measures:

The aforementioned substation inspection localization method based on UWB, wherein in step 4),

If weighting matrix is W,

Acquire weighted least-squares location estimation are as follows:

X=(A^TWA)^-1A^TWb。

The aforementioned substation inspection localization method based on UWB, wherein W1 value range is 0~1.

The aforementioned substation inspection localization method based on UWB, wherein t_reA、t_reBIt is set as 40ms.

Compared with prior art, the beneficial effects of the present invention are:

Location algorithm different from the past requires the location algorithm of equipment room time synchronization, and the present invention is using symmetrical bilateral two-way Location algorithm carries out ranging, and this method do not require label synchronous with base station time, do not require time synchronization between base station yet, and is based on Time Method is compared with based on time difference method, is had a clear superiority, and is effectively reduced the influence of clock drift bring, is reduced system Power consumption, reduce system cost, and ensure that positioning accuracy.

Detailed description of the invention

Fig. 1 is base station module structure chart of the invention；

Fig. 2 is label model structure chart of the invention；

Fig. 3 is substation inspection positioning flow figure of the invention；

Fig. 4 is label and base station location figure；

Fig. 5 is that base station B and label A information transmit schematic diagram.

Specific embodiment

The present invention will be further explained below with reference to the attached drawings and specific examples.

As shown in Figure 1, 2, the substation inspection location hardware system of the invention based on UWB is divided into three modules, respectively It is base station module, label model and server module.The base station module include microcontroller chip (model: STM32F407), UWB communication module (model: DWM1000), LED light, ethernet module.When base station operation, pass through base station serial port module Or ethernet module power supply, LED light are lighted, STM32F407 chip controls base station DWM1000 module receiving and transmitting signal, it Position data is transmitted to by server by ethernet module afterwards.The label model include microcontroller chip (model: STM32F103), UWB communication module (model: DWM1000), power module, LED light.When labeling task, pass through label Self-powered power supply, LED light are lighted, and the DWM1000 module of STM32F103 chip controls label receives base station signal, warp It crosses after regular hour delay and base station is sent data back to by label DWM1000 module.The above-mentioned substation based on UWB patrols Examining and determine position hardware system is existing common system.

The present invention is based on above system, carry out substation inspection positioning, as shown in Figure 3 the following steps are included:

1) label A enters the search phase, finds the base station for ranging, and base station as shown in Figure 4 is set as four or more, mark It signs A and message blk is sent using broadcast type every fixed delay, the base station B for receiving message blk signal replys label A one and disappears Breath wraps, and the ID of the base station is carried in message package；

2) in ranging process, base station B as shown in Figure 5 and label A will do it tertiary information transmitting, and label A is sent to base station B Poll message, label A record timestamp t1 at this time, and base station B is received after poll message by one section of delay t_reBIt sends and determines afterwards Message RNG message records timestamp t2 at this time to label A, and label A records timestamp t3 at this time after receiving RNG message, By one section of delay t_reAAfterwards, the timestamp recorded is attached to final message and is sent to base station B by label A, and base station B is received Final message simultaneously writes down timestamp t4 at this time；Remember t_A=t3-t1, t_B=t4-t2；

Base station B extracts the timestamp in final message, calculates the skyborne flight time TOF of wireless signal, then

t_A=2TOF+t_reB (1)

t_B=2TOF+t_reA (2)

According to above formula, our available equatioies

t_A+t_B=4TOF+t_reA+t_reB (3)

In formula (3), t_A、t_reA、t_BAnd t_reBIt is given value, then the theoretical value of flight time TOF is

In practical projects, the influence for considering chip clock drift, then measure the flight time are as follows:

e_AFor the clock drift of base station, e_BFor the clock drift of label, according to formula (4) and formula (5), the theory of flight time Error delta TOF between value and measured value is

Because of (t_reB-t_reA) > > TOF, above formula can be reduced to

t_reBIt represents label and receives the UWB signal and send a signal to the delay between base station again that base station is sent；t_reA It represents base station and receives the UWB signal and send a signal to the delay between label again that label is sent.e_AFor base station microcontroller The clock drift of device, e_BIt drifts about for the microcontroller clock of label, is the build-in attribute of hardware, is generally taken from chip handbook； t_reA、t_reBSelf-setting in software, generally 40ms.According to above formula, the time error based on bilateral round trip ranging compared with It is low, the influence of clock drift bring is effectively reduced, and compared with based on Time Method and based on time difference method, had obvious excellent Gesture, it does not require equipment room time synchronization, therefore system does not need time synchronization module, reduces the power consumption of system, protects simultaneously Positioning accuracy is demonstrate,proved.

3) propagation rate of known signal is electromagnetic wave rate, acquires the distance between base station and label d=c*t, wherein c For electromagnetic wave rate 3*10⁸M/s, t are to measure flight time TOF_c；

4) each base station sends range data to server, and server program benefit is shown a C language, in Linux system Compiling is realized.In the server, the current coordinate of label is calculated according to location algorithm every fixed time period 120ms,

If the three-dimensional coordinate of each base station is x_i, y_i, z_i, i=1,2 ... n, n >=4, the tag A coordinates that need to be positioned be x, y, z, The distance of label A to each base station is d_i, transfinited with least square solution and determine the mode of equation group, acquire the three-dimensional coordinate of label A；

Specifically: range formula is expressed as AX=b,

Using least square solution range equation, the least square location estimation of label is acquired are as follows:

X=(A^TA)^-1A^Tb。

The present invention is in position fixing process, using the three-dimensional coordinate of 4 or more base stations as reference mode, the position of positioning node Setting is the relative coordinate obtained according to reference mode.In actual measurement, inevitably there is a certain error, therefore Need one weight of distance measurement result to every node that positioning can be improved in this way for indicating its range accuracy and position precision Precision.Since in actual measurement, inevitably there is a certain error, it is therefore desirable to the distance measurement result one of every node Positioning accuracy can be improved for indicating its range accuracy and position precision in a weight in this way.

If weighting matrix is W,W1 value range is 0~1.Acquire weighted least-squares location estimation Are as follows:

X=(A^TWA)^-1A^TWb。

In addition to the implementation, the present invention can also have other embodiments, all to use equivalent substitution or equivalent transformation shape At technical solution, be all fallen within the protection domain of application claims.